 The road to reactor design development has led to many dead-ends or defunct designs. And one such installation would leave a cave contaminated and a country's nuclear ambitions almost in tatters. If you like what we do here at Plain Difficult, consider helping the channel grow by liking, commenting and subscribing. Let's get started. After a few industrial accidents we are back to looking at a nuclear industry disaster. And this one has been on my to-do list for quite some time. This is mainly due to it being a nuclear reactor inside an underground cavern, James Bond Villain style. Today we are looking at the ill-fated and short-lived Lucien reactor in Switzerland. I'm going to rate it here on my disaster scale. Lucien sits in the west of Switzerland and is a small town with a population today of around 4,000. However, we will be going back to 1968 when the town was the home to a new experimental reactor. In the late 60s Lucien had a population of roughly 2,000. Switzerland's power supplies in the late 1950s and early 1960s used hydroelectric, imported coal and oil. As the atomic age became a thing of not just the early nuclear innovators, Switzerland took interest in this new potential of power. In 1955 a private company, Reactor AG, was set up with shares owned by Swiss industry and the federal government. In 1958 a federal atomic energy commission was set up with an advisory panel for the country's atomic aspirations. Reactor AG was eventually wholly owned by the government. Part of this new burgeoning nuclear industry was the desire to have a completely designed, constructed and owned nuclear reactor. By designing and building its own reactors, the Swiss government hoped to monopolise on the country's atomic industry. For this to happen, a reactor needed to be built and this leads us back to that little town in West Switzerland. In July 1962 construction began with the reactor built into a hillside on the southern outskirts of the town. The reactor complex was housed inside three rock cabins with a horizontal connecting tunnel. The control room was above ground at the end of this passageway. In theory building a reactor underground makes sense as you already have a natural containment structure. However, this would cause problems in an accident as limited space meant any remediation works would cost a lot, but we will have a look into that a bit later on. The designer reactor made use of lone enrichment uranium. This was picked due to the small size of the reactor and was cheaper and easier to source compared to fuel of high enrichment. Because of the lone enrichment fuel, heavy water was used as the reactor's moderator and this slowed down neutrons to ensure a more even chain reaction. This lab moderator was one of the two that could be used for lone enrichment uranium. The other being graphite. The reactor used a different form of coolant than its moderator and this was pressurized CO2. The reactor had 73 fuel elements consisting of slightly enriched metallic uranium rods clad with magnesium zircoi alloy and was situated in seven vertical channels bored into a graphite block that was centered in a zircaloi pressure tube with pressurized CO2 for cooling the fuel rods. These fuel cans had fins around the outside to help with cooling similar to what you find on an air-cooled engine or the ill-fated wind scale. The core was split into two halves each with a CO2 blower and a steam generator. The coolant gas was pumped into the top channels at 6.28 MPa and 223 degrees Celsius and exited the channels at a pressure of 5.79 MPa and at a temperature of 378 centigrade. The vertical pressurized tubes were located in an aluminium calandra that contained the reactor's moderator. The heat in the primary cooling loop used a steam generator interacting with a secondary loop containing water which, after the steam was created, was used to turn a turbine in turn generating electricity. Surrounding the core was a steel and concrete structure used as shielding. The unit had six safety rods and four control rods used for complete shutdown and output power management respectively. As always with the reactor, the unit had a scram facility to shut it down in the case of an emergency. The reactor produced 30 MW of heat which was used to create 6 MW of electrical energy and it first went critical in 1966. Two years later, throughout 1968, the reactor had run for around 70 days at varying power levels all the way up to 100%. However between October 68 and January 69, the reactor was shut down to investigate a number of odd occurrences. It's notably moisture in the CO2 coolant loop. Tests using two different blowers showed some serious water ingress. In December 1968, during a blower test run, water was swept into reactor core, although the moisture only reached the outer fuel elements. In total an estimated 50 litres of water was thought to have entered the primary loop. Water settled inside the pressur tubes of the coolant within the core and began to corrode the magnesium alloy components. Eventually this weakened the vital coolant channels. In January 1969, in preparation for restarting the reactor, both blowers were powered up and around 15 litres of water was dislodged. However, not just the water was moved, corrosion products produced over four weeks of the moisture ingress also were spread around. These products settled and blocked some of the coolant channels. On January 21st 1969, the reactor was made critical, shortly after four o'clock in the morning. And in the course of the day the power was increased in steps, with checks and corrective work being performed during the intervals. As the reactor was started up, it reached a 9 megawatt power level. Temperature sensors were installed throughout the core, however not every fuel channel had the ability to check how hot it was getting. What the operators didn't know was that the channels where the corrosion products had settled in started to see a rise in fuel temperature. Around 5.15pm the power was increased to 12 megawatts. At this time core position 59 was at a temperature of around 640 degrees centigrade. 30 seconds later, the fuel element in position 59 began to melt, starting with the fins of the fuel can. Shortly after the can temperature reached over 1100 degrees centigrade. Some of the fuel rod's graphite column blew apart, further rupturing the pressure tubes. The melting and rupturing of the fuel elements led to a release of fission products into the coolant, initiating a reactor scram. This was the first point that the operators had realised that something was going wrong. The heavy water entered the ruptured fuel elements and began to heat up. Fission products made their way into the Calandria, increasing its pressure. The Calandria was equipped with several rupture disks for the event of an over-pressurisation. One of these gave way, leading to the moderator now contaminated being released into the reactor structure. A bubble of CO2 then forced a total around 1100 kilograms of moderator into the spaces between the various radiation shields around the core. The pressure in the tank was temporarily reduced. The fuel element continued to burn, increasing the core temperature to near 1800 degrees centigrade. The heat caused more of the fuel elements to buckle and the pressure increased burst the final Calandria rupture disks. The scram initiated the isolation of the reactor cavern by automatic closure of ventilation ducts. In total around 7400 kilograms of moderator was expelled from the Calandria and eventually the spillage made its way into the cavern. Initially a gamma dose rate of around 120 rads an hour was measured in the upper chamber of the reactor cavern. However this quickly reduced in the following hours. The reactor destroyed one fuel element and seriously damaged the moderator tank of the reactor, meaning serious amounts of contamination had escaped. Some had escaped the apparently isolated main cavern into the other two parts of the complex and eventually made its way to the control room 40 minutes after the initial fuel damage. The control room experienced 10 times the maximum admissible concentration for occupation exposure. The operators donned gas masks to continue managing the disaster. After analysis of the gaseous contamination in the control room it consisted of Rebidium 88 which has a short half-life of around 18 minutes. The contaminated air had made its way out of the main containment via holes cut into the cavern for cables. It was thought that during the active phase of the event doses in all cases were less than 150 millirems. Now the damage to the fuel and Calandria, the Swiss operators deemed the reactor to be a write-off and thus went with it the dreams of a wholly indigenous nuclear program. On top of that the country had a massive radioactive hole in the ground. Initially an analysis was taken of the gases inside the main reactor cavern. It was decided that it could be vented to atmosphere via the plant's iodine-filtered vent stack. Between January 1969 and March 1970 the initial phase of decontamination was undertaken and consisted of recovery of as much heavy water as possible drying the cavern atmosphere and removing tritium vapours. Next came the dismantling of the unit starting with defuelling except for the damaged fuel element. Then the pressure and Calandria tubes were cut and removed. The Calandria had to be sectioned for packing for disposal. After the upper portion of the Calandria's vessel had been removed the damaged fuel element and its pressure tube were finally recovered. The final steps included disassembly of the highly contaminated systems and decontamination of the station for treatment of radioactive material. Dismantling and decontamination was completed by 1973. The inside of the caverns were painted to keep in the contamination of an estimated 40 gigabit quills. All the works ended up being far more difficult than the usual decommissioning of a reactor. This was because of the inferior idle location for an NPP being underground. In 1988 the decision for two of the caverns to be filled with concrete entombing the dangerous remains was made by the Swiss owners of the site. After final completion of the decontamination in the mid-1990s regular monitoring has taken place on the former site. Nuclear power did not end however in Switzerland as up to around 40% of the country's energy is provided by nuclear power. However the plants reactor designs were supplied by foreign nations. The Swiss government has said that it will not build any new plants and will not replace any of their current operations once they have reached operational life expectancy. And hydroelectricity is safer unless you're at Sayano Shyshenska. I hope you enjoyed the video. If you'd like to support the channel financially you can on Patreon from $1 per creation. And that gets you access to votes and early access to future videos. I have YouTube membership as well from 99 pence per month and that gets you early access to videos. Check me out on Twitter and also if you want to wear my merch you can purchase it at my Teespring store. And all that's left to say is thank you for watching. In properly stored deadly materials unsurprisingly spread their uncontrolled toxicity around their local environment. This is exactly the case for a super fun site known as the Westlake landfill. And due to its radioactive waste has caused heightened levels of cancer in the local area. The site would fall victim to decades of indecision and ultimately little work to clear up the issue. Landfills are by design a method of sweeping the mess under the proverbial rug. They are a place to store waste for a long period of time. Naturally much of the items placed in landfills are not easily recyclable either due to financial or technical limitations. A landfill site in Missouri which was originally used for pretty standard municipal waste and construction refuse ended up being the resting place of soil contaminated with radioactive material. Today we are looking at the Westlake landfill and I'm going to rate it around here on my disaster scale. The Westlake quarry company in 1939 began working on a site in Bridgetown, St. Louis County, Missouri which is around here on the map. The 200 acre tract is located about four miles west of St. Louis's Lambert Field International Airport. The site was originally used mainly for excavating limestone and crushing operations and this was the case for around a decade until another use for some of the land was highlighted. You see once a quarry has stopped being useful a massive hole in the ground is left presenting another revenue stream for the site owners. The new use for some of the site began in the early 1950s with local waste and both solid and industrial liquid waste being dumped in the unlined quarries. Around 75 percent of the landfill site was located on the flood plain of the Missouri River at around 440 feet above the mean sea level so far so normal although the landfill was operating unregulated meaning anything goes in the big hole. And this would lead to the ultimate in stupid waste disposal and that was the dumping of radioactive waste in 1973. But where did the nuclear waste come from? Well our story starts with the Manhattan Project. The Malincrot Pharmaceuticals Plant in St. Louis was the sole uranium oxide supply to the Manhattan Project. Between 1942 and 1958 the plant processed approximately 50,000 tons of uranium. This created some 133,000 tons of process waste, residues and scrap which were stored at the St. Louis airport site with a plan to find a suitable long-term storage solution. In the early 1960s the Atomic Energy Commission offered 116,000 tons of the waste stored at St. Louis airport site for sale. They were purchased by the Continental Mining and Milling Company from Chicago in April for the princely sum of $126,500. The material was in 1966 transferred to a property on Lattie Avenue in Hazelwood, Missouri where it sat in the open. After a change of ownership to Cotta Corporation some of the residues were dried off and sent to Canyon City, Colorado. The remainder of the materials mainly consisting of 8,700 tons of leach barium sulfate were removed from the property in Lattie Avenue and mixed with around 39,000 tons of topsoil that had been contaminated by the storage of the residues. In 1970 the NRC undertook a survey of the Lattie Avenue site and decided that the area needed remediation works. Cotta Corporation took the mixture of contaminated soil to the Westlake landfill where it was illegally dumped in 1973. The toxic waste had only been covered in about 3 feet of soil. In 1974 the NRC undertook an inspection of the Lattie Avenue site. This was to make sure that the area had been decontaminated effectively. The inspectors were informed that the remainder of the materials had been disposed of at a local landfill have a Cotta Corp lied about the particular dumping site. The waste was dumped at two places on the Westlake landfill site. The northern dump site consisted of around 13 acres and sat atop around 16 feet of previously dumped municipal waste. The contaminated soil formed a continuous layer from up to 15 feet thick and consisted of around 130,000 cubic yards of soil. The second southern dump site was much smaller at three acres consisting of around 30,000 cubic feet of waste and was located near the landfill office. This part of the waste was dumped in one of the disused quarry pits which had a total depth of 60 feet and was filled with municipal and industrial waste. From 1974 the NRC and AEC investigated the waste that was dumped in the unregulated landfill. From 1980 the NRC contracted Radiation Management Corporation to undertake a number of radiation surveys of the site to establish how much contamination was present at Westlake. External gamma radiation was measured at levels as high as 3,000 to 4,000 micro-rontkins per hour above the northern dump site. A year later these levels were recorded lower at 1,600 micro-rontkins per hour. This was due to more refuse being dumped over the contaminated soil. Around 61 soil samples were taken at Westlake and elevated levels of uranium-238, radium-226, radium-223, lead-211 and lead-212 were detected. Again like the external gamma surveys the majority of activity was found to be over the larger northern dump site. For subsurface samples a method of logging was undertaken where holes were drilled into the areas where the highest levels of contamination were thought to be located. A total of 43 holes were drilled including two offsite holes for water monitoring, 11 in the southern dump site and 32 in the northern site. The survey data indicated that the average of radium-226 concentration in the waste was around 90 picocuries per gram and estimates of the average thorium-230 concentration to be around 9,000 picocuries per gram. Further surveys were undertaken until 1988 when the concern of the amount of radioactive wastes prompted a need for remediation works. This was largely due to the presence of thorium-230 which is a pretty nasty material with a half-life of 77,500 years meaning it is a headache for a very long time. Westlake was proposed for superfund site status on the 28th of October 1989 and was placed on the national priorities list designating it a superfund site on August 30, 1990 by the EPA. The site was not recognised as a danger and it was ranked pretty low on the priorities list. This would lead to years of indecision and not much actual cleanup work being done. The site was divided into different areas called operable units 1 and operable units 2. OU1 consisted of the northern dump site and the southern dump site labelled as area 2 and 1 respectively. The other main area of the landfill was operable unit 2 which consisted of non-radioactive waste areas. The radioactive areas were surrounded by a buffer zone and the whole site was fenced off restricting access. However it wouldn't be for nearly 20 years that a remediation plan would be settled upon. In 2008 after many years of investigations plans, public consultations and surveys an action plan was finally agreed upon. This suggested containing the contamination by placing a multi-layer cover over 40 acres of the landfill. However ever since the materials were first dumped at Westlake the contamination seeped into the groundwater via the online quarry. This leads us on to a potentially dangerous situation as in December 2010 a self-sustaining high-temperature reaction that consumes waste underground was discovered inside the non-radioactive OU2. This event brought around the fears of the underground reactions spreading to the reactive waste in doing so releasing radionuclei into the air in the form of smoke. The underground high-temperature reaction produces rapid settlement of the landfill surface making the area unstable. Even if it didn't make its way to the OU1 the fire has caused unsafe levels of toxic gases to reach the surface. Due to the toxic fumes produced the EPA made a decision that excavating the OU2 to put out the fire would be an environmental catastrophe as large amounts of burning toxic waste would be released into the atmosphere. Rather worryingly the EPA discovered that some of the radioactive waste was within the OU2 perimeter placing it around 900 feet from the underground fire. Again like OU1 the EPA has decided to monitor the situation but not really do much. Until August 2013 when Republic services the landfill owner finished covering over the South quarry with a plastic cap. One of the goals of putting the cap over the landfill was to try and keep oxygen from getting to the underground fire hopefully slowing it down. In December 2014 an assessment by the US Geological Survey found unhealthy levels of radium in the groundwater near the landfill. However this water is not used by the local population although it does show that OU1 is not contained. Needless to say this has caused serious concern with local residents who have reported respiratory issues, heightened self-reported levels of cancer and other long-term health issues. However the EPA has claimed no elevated risks to the local population with an agency for toxic substances and disease registry evaluation in 2015 claiming no risks as well. The local population in the face of straight-up denial are increasingly getting frustrated and protests and community meetings are regularly held to try and boost the profile of the disaster. In 2018 a final remediation plan was set and that would involve removal of around 70% of the contaminated material to proper disposal and a protective cap would be placed over the remainder of the waste at Westlake. It is thought by the EPA that the commencement of remediation works would be between 2020 and 2021. What strikes me most about the whole Westlake landfill issue is not only it is a still ongoing event but it doesn't seem like a lot has happened. Where little remediation works have been undertaken to date apart from regular monitoring. Sorry for the lack of satisfying ending to this video in comparison to an other unregulated dump site but when under the control of the EPA the love canal. The results at Westlake are rather underwhelming. This is mainly due to the frustratingly slow remediation process which included survey after survey and consultation after consultation with little actual ground work being undertaken. Understandably if you live near you would not be happy especially when the initial contaminated waste found their way to Westlake almost 50 years ago. I hope you enjoyed the video. If you'd like to support the channel financially you can on Patreon from $1 per creation and that gets you access to votes and early access to future videos. I have YouTube membership as well from 99 pence per month and that gets you early access to videos. Check me out on Twitter and also if you'd like to wear my merch you can purchase it on my Teespring store and all that's left to say is thank you for watching. The manufacturer and storage of explosive chemicals is a recipe for disaster if done incorrectly and this would be the case in 1988 when an explosion would affect an area of roughly a 10 mile radius. If you like what we do here at Plain Difficult help the channel grow by liking commenting and sharing and if you haven't already subscribing. Let's get cracking on with the video. Pepcon is a word that has popped up in the comments section of several videos. Not 100% knowing what it was I looked into a few reports on the subject and oh man this is one big of an explosion. Today I'm going to rate this incident here on the Plain Difficult Disaster Scale. It's scary to think that sparks from welding can cause a fire that led to an explosion and destruction on this scale but I suppose the result is pretty obvious when the site that the fire started in was one of two major producers of ammonium per chlorate worldwide which is a key component in rocket fuel and we know how explosive that can be. The Pacific Engineering and Production Company of Nevada or Pepcon for short operated in Clark County, Nevada approximately 10 miles southeast from downtown Las Vegas near the city of Henderson which is around here on a map. Oddly the other major ammonium per chlorate producer was only under two miles away and was operated by Kear McGee. The Pepcon plant was constructed in the 1950s in and at the time isolated desert area. However the area was seed growth in the 1970s due to the expansion of Las Vegas' Metropolitan Sprawl. The nearby city of Henderson in the late 80s had a population of around 50,000 people. The Pepcon facility specialized in the manufacture of oxidizer ammonium per chlorate which was used in the space shuttle program, SLBMs launched from nuclear submarines and other rocket programs. The buildings on the eight acres site were mostly steel-framed with fiberglass walls and also randomly the plant's nexel neighbor was a marshmallow factory. The plant manufactured the AP in a four-step process starting off with the electrolytic oxidation of sodium chloride to sodium chlorate in the chlorate building. Then the electrolytic oxidation of sodium chlorate to sodium per chlorate happened also in the chlorate building followed by a reaction between the sodium per chlorate and ammonium chloride to produce ammonium per chlorate in agitator tanks within the process building. The final step being AP crystallization, filtration, dying, screening and the blending to customer specifications in several buildings. A tragic turn of events would eventually lead to the incident in 1988 and this was the challenger shuttle disaster. This happened on the 28th of January in 1986 where the space shuttle exploded killing all seven crew members. Subsequently all national launches were grounded whilst the investigation was undertaken. This however left a problem for Pepcon who now had a larger than normal stockpile of rocket oxidizer. This would end up being stored in several hundred aluminium bins and several thousand plastic barrels. The classification of AP in 1988 was a class for oxidizer and had been detonation tested in large-scale quantities leading to a full sensor security. It was estimated that a total of 8.5 million pounds were on the site in 1988 which is roughly around 3.8 million kilograms. The site was not set up well for storing large amounts of combustible materials. The only building to have a sprinkler system was the main offices and no proper fire alarm was installed on site. No official evacuation plan was in place at Pepcon Beyond Get Out if you encounter a big fire. This brings us on to the 4th of May 1988. Now there are several different theories to the initiation of the disaster but I'm going to side with the NASA report. On the day 77 employees were at Pepcon, one of whom was mobility impaired in a wheelchair. At 11.30am employees were repairing the plant's drying structure which had wind damage steel and fibreglass segments. Sparks from a welding torch ignited some of the fibreglass. The workers attempted to extinguish the fire with a hose. Residual AP was on the structural parts of the building and this fuelled the spread. The fire continued on to reach some of the APs stored in plastic drums. The employees who were fighting the flames abandoned the effort when extinguishing was doing little to help. 75 of the staff on site by this point had already started to evacuate the danger area, some on foot and others in their vehicles. One of the staff members had stayed behind to alert the authorities of the impending doom and the other, the person in the wheelchair, was unable to evacuate. Eventually the inevitable happened and the temperature rose to a level to start an explosion and around 20 minutes after the initial ignition disaster struck. The explosion spread the flames further around the site, eventually reaching the aluminium-contained AP, intensifying the fireball. After around 4 minutes a second larger explosion engulfed the Pepcon facility, leaving barely anything behind. Henderson City's Fire Chief saw the huge plume of smoke 1.5 miles away from the facility and ordered all units to make their way to launch any possible rescue efforts. He reached nearby site as the explosions were happening. Responding fire trucks were also caught up in the explosions injuring many of the first responder firefighters. The shockwave from the second explosion had caused significant damage with vehicles, buildings and window glass all mangled up from the intense release of energy. A 15 feet deep by 200 feet wide crater was left at the Pepcon epicentre. Other nearby fire departments also arrived to assist with the injured first responders. The decision to not attempt to fight the remaining fire was made as further explosions posed to greater risk. The smoke from the explosion reached several thousand feet into the air and was spread over the town of Henderson. Five more smaller explosions erupted as individual stores of AP combusted. The two main explosions were registered as 3.5 on the Richter scale all the way in California. It will be later estimated that the second explosion would be the equivalent yield of 1 kiloton of TNT, about 120th the yield of the Trinity test. The only remains of the site was a flame plume created when a high-pressure natural gas line beneath the plant was ruptured during the explosions. A 5 mile exclusion zone was set up around a facility evacuating all within, making use of almost every public service available, including the Henderson Police Department, Nevada Highway Patrol, Las Vegas Metropolitan Police Department and the Nevada National Guard. Around an hour after the first explosions it was concluded the airborne products would be a respiratory irritant but not highly toxic. Cases of respiratory issues were reported as far as 30 miles away. The fire eventually petered out after the natural gas line was cut off just before 12 noon, allowing initial inspections of the site to be undertaken to assess the risk of further explosions. But at the beginning of remediation works, crews had to wear protective clothing and respirators due to the leaking chemicals and the airborne irritants from the explosion. The initial work proved difficult, with no supply of water meaning everything had to be trucked in from nearby Henderson. Of the 100 employees for PEPCON and a nearby marshmallow factory, between 20 and 30 needed hospital treatment with varying injuries. It took six hours to account for everyone on the site and all was accounted for apart from two. These two missing persons were the wheelchair user and the other who had stayed behind to report the incident. They were the only fatalities of the disaster. This was not the end of the story's effects sustained by the disaster however. An estimated 300 further people were injured in the surrounding area from falling debris, broken glass from the shockwave and other materials released by the explosion. The emergency services advised the hospitals in the local area to activate their disaster plans how the vast majority of the injured persons were minor. The overflow of patients led to triage being undertaken in the car park at nearby St. Rose de Lima in downtown Henderson. The damage affected a radius of around 10 miles including broken windows and doors ripped off their hinges. At McCarran airport in Las Vegas, windows were cracked and doors were pushed open and the shockwave affected a Boeing 737 on final approach. PEPCON had only a $1 million liability insurance policy and this would obviously not be enough to cover the damage caused by the disaster. Needless to say, this would result in a lawsuit between multiple lawyers and insurance companies and would result in a 1992 settlement of $72 million. The disaster opened the eyes of the regulators and industry officials to the risk of AP and the site today has been developed into a retail area. I hope you enjoyed the video. If you'd like to support the channel financially, you can on Patreon from $1 per creation and that gets you access to votes and early access to future videos. I have YouTube membership as well from 99 pence per month and that gets you early access to videos. Check me out on Twitter and also if you're into where my merch, you can purchase it at my Teespring store and all that's left to say is thank you for watching. The handling of the chemical process for the purification of uranium is unquestionably dangerous if confronted by either human or technical fault. In the same year of the near tragic disaster of the criticality accident at the Y-12 plant, an operator at Los Alamos would not be so lucky. We're back here with yet another criticality accident. This one has been on my list for a while and I've been looking forward to having a deep dive into the Cecil Kelly incident. The late 1950s was a bad time for nuclear accidents. With windscale in 1957, kistium in 1957 as well, the NRU fuel accident, the Y-12 and the Cecil Kelly criticality accidents in 1958, just to name a few. Needless to say, if you're working back then in the nuclear industry then you better have had good insurance. Today we are back at the Los Alamos laboratory for the third and lesser known fatality from a criticality event, the first two being linked to the Demon Corps. Although not as scary sounding as the Demon Corps, the 1958 criticality that led to an operator's over-exposure and subsequent death is arguably far more worrying as the time between exposure and death was just under two days. Los Alamos, post Manhattan project, had been renamed the Los Alamos Scientific Laboratory and things had changed from the 40s where nuclear weapons were built by hand by experts. Instead the laboratory had started to move towards mass production using lower skilled workers almost like a factory line. Even though bomb manufacturing had changed, the lab still undertook multiple experiments using different radioisotopes and this necessitated reprocessing and recovery. However an unusual set of circumstances would result in a supercritical mass as the area of the incident typically only dealt with lean residues from plutonium recovery operations. These lean residues were usually sub 0.1 grams per litre containing plutonium and amoresium. The process used a chemical we've seen before in this channel, tributyl phosphate, also known as TBP, which was used to separate the two radioisotopes and this was carried in an organic solvent. The solution was evaporated after being extracted to an aqueous solution to concentration resulting in a solution containing a few grams of plutonium per litre. The solution is then fed back into an earlier part of the process. The now extracted plutonium rich solids are then sent to another part of the plant for processing into smaller batches. Now that was a normal operation of the plant at Los Alamos, however at the time of the criticality event an inventory was being undertaken. This involves stopping the normal flow of work to evaluate the residual materials in the processing machinery of plutonium content. The solution was filtered for evaluation and whilst this is undertaken the process machinery was cleaned. On the 30th December 1958 dilute aqueous and organic solutions from two vessels were washed into a single large vessel. The aqueous solution was removed from this vessel and remains of approximately 200 litres of material including nitric acid wash was transferred to a 850 litre 96 cm diameter stainless steel tank fitted with a mechanical stirrer. The kind of mixer you'd find at a bakery albeit for mixing dangerous materials which with my cooking skills is indistinguishable. This tank contained about 295 litres of acoustic stabilised aqueous organic emulsion and the added acid from the new material separated the liquid phases. The liquids ended up settling into two layers the top being 160 litres organic material containing around 3.27kg of plutonium. The bottom layer consisted of around 330 litres of aqueous solution and had around 60g of plutonium in it. A critical mass was not achieved at this time while the two layers being separate. The top layer was 20.3cm thick and criticality would have been achieved by a thickness of 21cm. Cecil Kelly, a lost animus worker with many years of experience was about to set off a power excursion which would end his life without even knowing it. Kelly had turned on the tank stirrer at around 4pm on the 30th December and as the agitator blades spun up to its set 60 rpm the two layers started to mix together. To observe the mixture the tank had a couple of viewing ports protected by thick glass. Kelly was standing on top of a small step ladder to watch the mixing in operation. The motion changed the reactivity from about $5 subcritical to super prompt critical and a power excursion occurred. Almost immediately Kelly experienced a blue flash and a bang from within the tank. This knocked him off the ladder realising something was wrong he turned off the mixer. He turned the mixer back on to hear a rumbling sound. By now Kelly had started to feel burning over his skin and was assisted by two other operators to a shower moving back past the tank. One of the operators assisting turned off the mixer. Kelly was heard exclaiming I'm burning. Initially it was thought that Kelly had experienced some kind of acid burn hence the showering however it was far worse than that. A radiation alarm set to go off at 10mph 175ft away was activated by the short sharp increase from the excursion. This caused an evacuation of the site at 4.35pm. To make the tank safe again the unknown concentration of plutonium solution had to be removed. To facilitate this an array of small tanks was fabricated and placed 100ft away from the mixing tank. All the solution taken from the tank was analysed to figure out how much plutonium was within. A drain line was fixed to the underside to drain the fluid as it was unknown on the level of radioisotopes in the solution a temporary shield was set up to protect operators. A maximum reading of 1 rem per hour was taken from the tank reducing to 50mrems after it was fully emptied. Now back to Kelly. Within 15 minutes of exposure he had experienced severe shock eventually becoming unconscious. His average whole body dose was first estimated by measuring the radioactivity of his blood. This showed sodium and other light metals had activated into radioisotopes such as sodium 24. It was estimated he received 900 rad from fast neutrons and 2700 rad from gamma rays giving a total of 3600 rad. However in a later post mortem this figure was closer to 4000 rad. 70 rad and above can cause acute radiation sickness. 500 rad is almost certainly a lethal dose. 6 hours post event Kelly's white blood cells virtually disappeared from his peripheral circulation hinting at a deadly downward spiral. 24 hours post event a bone marrow biopsy was taken to show watery like substances instead of a healthy bloody one. On the second day post exposure Kelly experienced hard to control abdomen pain, lost all colour to his skin and following an erratic pulse passed away. What was strange was how an operator with over 11 years of experience had been in the centre of an accident like this. In an AEC report it was highlighted that Kelly had deviated from the instructions mixing multiple batches in the same tank probably believing he was dealing like most other days with low concentration solutions. However this mistake sadly brought him a slow and painful demise. Similar to the Y12 complex, Los Alamos had employed strict administrative controls to prevent criticality of the solutions processed on site but was planning on getting rid of the larger tanks for more safe geometry containers. Administrative controls had been used on the site for seven years successfully and were considered acceptable for the additional six to eight months but it would be required to obtain and install the improved equipment. Ironically during this period the site experienced a breakdown in controls and a fatality from a power excursion. The accident along with Y12 and Wood River Junction really shows how criticality controls can't be relied upon as human nature seems to override the strict discipline needed. All these incidents help push forward geometry safe controls for fuel and waste processing. However again human nature has caused other events such as the Toquimera criticality. I hope you enjoyed the video if you'd like to support the channel financially you can from $1 per creation and that gets you early access to videos and access to votes. I have YouTube membership as well and that gets you from 99 pence per month Early access to videos. Check me out on Twitter and also if you'd like to wear my merch you can purchase it at my Teespring store and all that's left to say is thank you for watching. Imagine a whole town evacuated due to an uncontrolled underground fire. Well imagine no more as in Pennsylvania USA such a place actually exists. Today we'll talk about Centralia or more to the point the 1962 Centralia Mine fire and its effects on the community who lived above it. Thank you to my patrons for voting for this one. It is a slight bit different from a usual plainly difficult subject however it is still a disaster in its own right. I'm going to rate this video here on the Painted Plainly Difficult Disaster Scale. Here's a brief history of the town of Centralia for some context. Centralia is located in Columbia County in the US state of Pennsylvania which is around here on the map. Our story starts off for the princely sum of £500 which was the combined cost of settlers buying the land that would make up Centralia from Native Americans in 1749. Unknown to the purchasers at the time but the land would prove to have great value as it sat atop a large coal deposit. In the late 1700s the coal beneath was discovered however it wouldn't be for another 50 to 60 years that the deposits would be exploited. In 1832 Jonathan Faust credited as the town's founder opened the Bull's Head Tavern naming the new settlement Bull's Head. Talk about effective branding. In 1842 Centralia's land was bought by the Locust Coal and Iron Company and sent Alexandra Ray a mining engineer to design and build a small town to accommodate the miners. Ray named the town Centerville however the post office refused this name and instead Centralia was penned to the small town. Business started to boom after the mine run railroad and first town mines opened in 1854 and 1856 respectively. As a strange side note Alexandra Ray was murdered in 1868 during a period of robbery and homicide that engulfed the region. A record high population of 2761 was recorded in 1890. This would be the peak of the settlement's inhabitants. After several rights purchases and two world wars the population had sunk to 1986 people by 1950. An interesting and detrimental bootleg industry had developed since the financial crash of 1929 and this was the act of pillar robbing. You see a pillar is a column of unmined ore used to support the roof of mine. Ore is dug out in a grid formation leaving pillars kind of how a city street system is formed. This method is called room and pillar mining. Needless to say bootleg mining is really dangerous as it compromises the structural integrity of the mine and can and does cause collapses which make navigation of the mine system difficult. Remember this for later on. This leads us on to 1962 and the town of Centralia had an illegal dumping problem. This was due to the mainland field site being close to the public. A disused surface strip mine that had been cleared in the 1930s had been used as one such illegal dump and the council set about clearing it up. Although it's not known for certain most theories point to the start of the fire being linked to the clearing works of the strip mine. The local council hired a number of firemen to clear up the dump and this involved burning the rubbish even though this was against state legislation. This material was covering up a hole 15 feet wide and several feet high in the base of the north wall of the pit. The fire was started on the 27th of May 1962 and was doused with fire hoses after the material burned away quelling the visible flames. Two days after the initial rubbish burning the flames returned. Once again the hoses were used to douse the smoldering. A week later fire again was spotted and a bulldozer was called up to remove some layers of waste to try and find the source of the burning. This was when the hole leading to the maze of underground mines at Centralia was discovered and it was believed that this was the fuse that lit the disaster that was the Centralia minefire. On the 2nd of July complaints began to come into the council of foul odours coming from the area of the dump. Clarence Cashner, the head of the independent mines Breakermen and Truckers Union was called in to offer some advice on how to deal with the fire problem. Cashner suggested contacting Gordon Smith, an engineer of the Department of Mines and Mineral Industries to see what could be done. Upon evaluating the strip mines Smith suggested excavating as much of the burning rubbish as possible to prevent any more ignition of the coal seam. The price of $175 had to be authorised causing delays to the time critical situation thus kicking the cost into the proverbial long grass. Little did the council know but the fire spread into the coal seams inside the abandoned mines creating an uncontrollable inferno beneath the town streets. This was exasperated by collapsed mines from illegal pillar mining leading to difficulties tracking the route of the fire. Tests using gas detection equipment concluded that the large hole in the pit wall and from the cracks in the north wall contained carbon monoxide concentrations hinting at a disastrous coal mine fire. The Lee Valley Coal Company was notified of the fire. Although its true cause was withheld by the council, instead stating the source to be of unknown origin during a period of unusually hot weather. A meeting on the 6th August was set up at the strip mine with the LVCC and Seschke Hannah Coal Company to estimate the cost of digging out the fire. By now the financial burden was estimated to be near $30,000. Where $175 back in July sounded like a bargain. To add some toxic cherries to the dumpster fire cake, on the 9th of August deadly levels of carbon monoxide were detected closing all central area mines. The contract to clear the fire was put out to tender and on the 17th was awarded to Brady Inc. The company would end up excavating 53,000 cubic yards expending just over $27,000. Brady Inc. would cease excavation works on the 29th of October after discovering the fire had spread beyond the area. This would necessitate more serious works such as drilling and flushing, raising the cost significantly. A new project to stop the fire was set out and would involve flushing by mixing water and crushed rock into holes drilled ahead of the predicted path of the fire and this was to fill voids and reduce oxygen. The new project was estimated to cost $40,000 and on the 19th of November K and H excavating began drilling some 84 holes. This would last until March 1963 when the money went out after $43,000 was spent. Not to talk surprisingly the fire was not contained. By May 1963 the fire had spread approximately 700 feet eastward and the fire had heated up as seen by steam plumes emanating from the ground. Three plans were drawn up and submitted to the Secretary of Mines and Mineral Industries. Option 1 costing $296,000 consisted of entrenching the fire and backfilling the trench with incombustible material such as clay. Option 2 costing roughly $151,000 offered a smaller trench in an incomplete circle followed by extensive flushing. Option 3 was to drill more boreholes for flushing and would cost around $82,000. However, without proper funding the projects were all abandoned instead opting to dig a cheaper trench. However, by October the fire was discovered on either side of the incomplete attempt costing in excess of $32,000. In total the Council has spent over $100,000 with no effective control of fire essentially dooming the fate of Centralia. Work would not restart until November 1966 when federal state funding was secured and after a year spending another $326,000 it was again discovered that the fire had spread. Seven more projects would be undertaken in 1970, 1973 and 1980 including flushing, injecting fly ash and the digging of containment trenches all of which would not effectively control the fire. The ground beneath the town itself increased in heat reaching over 900 degrees Fahrenheit. Smoke poured from sinkholes and filled basements with gas necessitating evacuation of residents due to oxygen deficiencies and heightened levels of carbon monoxide. Increased reports of health issues plagued the residents with heightened respiratory complications. Locals became aware of the severity of the fire when the roads began to bulge and sinkholes appeared. Residents were divided between staying and abandoning the town. In 1982 the US Congress allocated $42 million for the relocation of Centralia's inhabitants. Unsurprisingly many took the money and ran as essentially the property was now worthless. In total 1,000 people moved out of the town and 500 buildings were raised to the ground leaving behind around 63 residents. Many buildings foundations became unstable as the fire burned away creating voids beneath the town meaning demolition was the only route left. Pennsylvania Governor Bob Casey invoked eminent domain on the town in 1992 condemning any remaining structures. The town was now all but gone except for a handful of steadfast residents. The order refused any rights. The order refused the rights of any resident to hand down or sell their property. By 2003 the US Postal Service revoked the town zip code and after 2009 evictions cleared out most of who remained. However Centralia today still exists with a population of 5. After 20 years of battling over eminent domain in 2013 the remaining residents were allowed to stay and part of the settlement gave a grand sum of $349,500 to the eight litigants. The town still receives a large amount of visitors in a strange form of abandon exploration and the main attraction of sorts being the Graffiti Highway which was once part of PA Route 61. Havis now has been covered up with dirt to deter visitors during the Covid pandemic. The fire is predicted to burn for at least another century as the seams of coal in the region act as a limitless source of fuel. I hope you enjoyed the video, if you'd like to support the channel financially you can on Patreon from $1 per creation and that gets you early access to videos and access to votes. I have a YouTube membership as well from 99p per month and that gets you early access to videos. Check me out on Twitter and also if you'd like to wear my merch you can purchase it at my Teespring store and all that's left to say is thank you for watching. This video is sponsored by Norpass, more about that later on. In 1975 and 1982 a Soviet designed RBMK reactor would experience a fuel melting event and would signal the dangers of a floor design but these signals would fall on deaf ears. This one is a double bill and an intro to the RBMK reactor. It will form part one of a new series of videos on Chernobyl. Think of this as how the Hobbit is to the Lord of the Rings which will be the Chernobyl disaster of 1986. Now both of these events in this video have very little in forms of official reports and this was due to the period of the time in which they existed where a Soviet government would cover up any hint that eastern block technologies were lacking in comparison to their western counterparts. Today's subject I will place here on the Plainly Difficult Disaster Scale. Leningrad NPP is a nuclear power station in Solznovibor, Leningrad, a blast, 43 miles west of modern day St Petersburg. However when the plant was first constructed the city was actually called Leningrad. Construction began on the site in 1967 and was the first to use the ill-fated RBMK reactor design. Unit 1 first began operation in 1973 with units 2 to 4 opening in 1975, 1979 and 1981 respectively. Each installed reactor had the same net power output of 925 megawatts of electricity, however they produced much more in thermal energy. Now let's look at the RBMK reactor and its design. The reactor's history can be traced back to the mid 1950s with the light water called graphite moderated 30 megawatts of thermal energy AM1 reactor in Obnisk. The design was further expanded upon in the 1960s with the AMB100 and the AMB200 designs. Between 1964 and 1966 Soviet designers needed to field a new reactor that was cheap, easy to build and maintain and be capable of electricity generation and also be able to produce plutonium for nuclear weapons. To facilitate this the designers opted to use light water for coolant and graphite for moderation, a style which is unique to the RBMK. Now moderator is used to reduce the speed of fast neutrons released from fission so they can better facilitate a chain reaction. Ideally moderators work without capturing any neutrons leaving them as thermal neutrons. So because of this most reactors need a moderator to work efficiently and different designs use different methods for moderation for example graphite, light and heavy water. The combination of graphite moderator and light water coolant offers up a strange result. As when compared to the PWR reactor which is one of the world's most popular designs the coolant and moderator in the form of light water are the same. The PWR is a very safe design as once the coolant heats up and turns into steam it loses its effectiveness as the moderator slowing down the chain reaction improving stability and eventually cooling down. However the RBMK didn't have this due to having graphite as its moderator and as it does not evaporate easily still does its job even if the coolant boils away. When the coolant heats up turning into steam it loses its neutron absorption capabilities creating three neutrons leading to an increase in reactivity. This is known as a positive void coefficient which is not instantly a dangerous design if the working parameters of the reactor do not rely on the neutron absorption of the water to stay safe. How the RBMK reactor design did rely heavily on the steam content of its core for its reactivity. This has to be countered by the control rods which regulate the overall power of the reactor leading to a very fine balancing act. If not properly managed an incident of a runaway can happen as the coolant heats up increasing the reactivity heating up the core more creating more steam leading to greater reactivity. This is called a feedback loop. Creates a similar result to a diesel engine runaway as shown in this very well shot video. The use of the graphite core allowed low enrichment uranium-235 fuel to be employed for power generation at only a quarter of the expense of heavy water reactors which had higher start-up costs and much more complex maintenance. Also low enrichment unsurprisingly cost less to make which was good for the Soviet accountants. The fuel was enriched to 2% and formed into pellets which were packed into a 3.65m long zircaloi tube forming a fuel rod. 18 fuel rods were arranged cylindrically into a carriage to form a fuel assembly which was then placed inside one of the reactor cores 1693 fuel channels. Within the reactor each fuel assembly is positioned in its own vertical pressure tube 7m long. Each channel is individually called by pressurized water which is allowed to boil exiting at the top at about 290 degrees centigrade. The steam is passed through a separator where it is sent to a high then low pressure turbine which turns the generators producing electricity. After which the coolant is run through a condenser called by a separate coolant circuit from a nearby water source. From there it is sent back to the core to complete the cycle. The reactor had two separate coolant loops which mirrored each other passing through its own half of the core. Each loop had four pumps, three for normal operation and one for backup. The graphite moderator consisted of multiple blocks placed next to each other with a gap filled with a mixture of helium and nitrogen gas that formed the core region of the reactor and was around the size of a small house. The graphite didn't receive any type of cooling meaning its operational temperature was around 700 degrees centigrade however the gas in between the blocks helped with heat conduction. The reactor was equipped with boron carbide control rods with graphite tips and these were used to shut down and regulate the power of the reactor. Most of them were inserted from the top however a number of shorter rods were inserted from the bottom for axial power control. The reactor had a safety shutdown in the form of the AZ5 button which once activated would initiate a reactor scram. The main top inserted rods provided automatic manual or emergency control. The automatic rods were regulated by feedback from in-core detectors. In addition to this some shorter rods were inserted into the bottom of the core to help combat hotspots of uneven criticality. In total the RBMK at Leningrad had 170 control rods. The final part of the RBMK was its containment or lack thereof. You see the doctrine at the time of the RBMK was that it was always going to be operated within design specs hence no risk of disaster but it didn't take into account human nature for buggering things up. What little protection to the outside world was provided was in the form of a reinforced concrete lined cavity that acts as a radiation shield. The reactor itself sat on a steel plate and was topped by a thousand ton steel cover. The steam separators were also housed in their own separate concrete containment. A contributory factor to the lower containment than other reactors was that it can be refueled whilst in power operation. To achieve this a large crane is situated above the reactor. This meant that building a massive concrete dome containment structure would be time consuming and more important costly. Now that is a basic overview of the RBMK. The version installed at Leningrad was a first generation design however there was a second generation design which was the type installed in Chernobyl unit 4. The second gen was virtually the same however one of the main differences was increased control rods to 211 and a reduction of fuel channels to 1661 in the graphite core. And now here's some words about this video's sponsor NordPass. NordPass is a one-stop shop for password management where security meets simplicity. If you're like me then you find it hard to keep track of all your passwords for different websites. I'm a very messy person and if it wasn't for Mrs Plainly Difficult I'd be living in a bomb site and my digital life is no different. So having somewhere safe and organised to deal with my passwords is a must. It helps as I like to keep my brain space free for arbitrarily rating disasters on my painted Plainly Difficult Disaster Scale. NordPass helps speed up the logging into websites as well by also filling information so I don't have to exercise my fingers all the time. The service also can store your debit and credit card information so you don't even have to need to try and find your wallet when buying online. Even can generate passwords which is definitely better than whatever I come up with. NordPass has both desktop and mobile applications for macOS, Windows, Linux, Android and iOS featuring a zero-knowledge architecture which means your data is encrypted before it even leaves your device to be stored on Nord's servers. You can also share passwords securely for websites like streaming services with people that you trust. If you want to give NordPass a go then you can for free at www.nordpass.com forward slash plainly difficult. You can even upgrade to a premium package which allows up to six active devices and a data breach scanner as well as many other bits and pieces. This leads us back to Leningrad and relatively new RBMK Unit 1 on 30 November 1975. It's very difficult to reconstruct the accident as at the time the reactor was surrounded by secrecy however some parts of a first person account does exist from a trainee who later worked at Chernobyl. On 29 November the reactor was being started up after some regular maintenance. Whilst powering up and reaching around 800 megawatts one of the reactor's turbo generators had control issues leading to the need to lower the power to 500 megawatts to take it offline. This was near 12 o'clock midnight and as with most disasters was the time for a shift change over. The night shift was tasked with the continuation of raising the power of the reactor. By accident one of the operators shut down the remaining turbo generator leading to a reactor trip causing a scram of the control rods. This in combination with the reduction of the power due to the TG being taken offline increased the level of zen and poisoning within the reactor. Not wanting to cause too much of a delay the chief operator issued the order to put the functional TG back online and to restart the reactor. The unit was restarted to the minimum controllable level however the poisoning of the reactor was at an unacceptable value reducing the operational margin to just eight control rods. This meant that nearly all of the control rods had to be fully removed from the reactor in order to achieve an output level for the TG to resume power generation. Again a scram was triggered shutting down the reactor due to uneven neutron power. This is due to the size of the RBMK core meaning that different areas could gain criticality whilst other areas remain poisoned which would lead to hot spots. Another restart was attempted and was more successful in reaching the minimum controllable level. At 6.15am the reactor capacity was raised to 1000 megawatts of thermal energy. By 6.33am the power was raised to 1720 megawatts. The operators had conducted too much of a fast rise of the reactor power deadly for the highly poisoned and small margin state of the reactor. Power levels to load the TG were achieved when operators received warnings of low water flow levels. The core had developed hot spots and the operators attempted to fight these by lowering some of the manual control rods whilst leaving the automatic ones to manage the overall power output. Scarily a new alarm sounded in the control room indicating moisture in the graphite near channel 1333. The presence of moisture in the graphite moderator hinted at a rupture in the high pressure coolant tube around the fuel meaning a potential meltdown. At this point the AZ5 button was pushed activating a scram shutting down the reactor. It was found that severe damage to the reactor core, one technological channel had collapsed and 32 fuel assemblies had burned due to operating the reactor in an unsafe manner. The damaged channel proved difficult to remove using the refuelling machine causing issues for workers. Due to improper confinement around 1.5 MCI was released into the atmosphere and 5km from the affected power unit, radiation levels were recorded at 600mAh immediately after the fuel damage. The accident was caused by the operators trying to make good the error of accidentally shutting down the operating TG. By doing so they worked outside the regulations for low power operation but the management culture at the time didn't consider this a major issue. Well how wrong they were. The Soviet Ministry responsible for nuclear industry was in charge at Leningrad making any information about incidents state secrets. This meant that no operators at other RBMKs would have even known about the fuel damage let alone learn from the mistakes. Right let's go on to the other lesser known Chernobyl incident and that is the fuel damage at unit 1 in 1982. Chernobyl NPP is a now shut down plant in Ukraine. Unit 1 was the same type that was used at Leningrad and was installed in 1972 achieving operation in 1977. There isn't a great deal to write about again as it was covered up at the time with the help of Viktor Brookanov who will most likely show up again on this channel in the future. However what is known from a KGB internal memorandum was like at Leningrad the RBMK reactor had been shut down for maintenance and have received fuel damage. The maintenance was scheduled to be complete on the 13th September 1982 and before this the reactor had to be tested. Upon restarting and reaching 700MW during the test run a fuel channel number 6244 was starved of water overheated and melted severely damaging the core and again leading to moisture in the graphite moderator. The issue wasn't noticed for between 20 and 30 minutes before an AZ-5 button activation allowing significant contamination of the coolant. Now it's unknown for certain what caused the coolant starvation as initially the operators were blamed however later on a failed valve was also seen as a potential cause. But it is difficult to know for certain due to the cover up. The channel was severely damaged and the repair turned into a dirty radiological clean up. It took almost a year to fix the damage from the accident and the core area adjacent to the destroyed channel was out of use indefinitely. The biggest issues from both these incidents was operators not working within the parameters set out for them either from negligence or pressure from management. The worryingly dangerous culture set out by management and their wider political sphere of nuclear power in the USSR would culminate in a much bigger disaster involving an RBMK in 1986. Thank you to NordPass for sponsoring this video. Sponsorships like this really help keep the lights on at Plain and Difficult HQ. Check out www.nordpass.com forward slash plain and difficult to try out for free. This is a plain and difficult production. All videos on the channel are Creative Commons attribution share alike licensed. Plain and difficult videos are produced by me John in a sunny southeastern corner of London UK. Help the channel grow by liking commenting and subscribing and check out my twitter for all sorts of photos and odds and sods as well as hints on future videos. I've got patreon and youtube membership as well so if you want to support the channel financially you can do through there. And all that's left to say is thank you for watching. The power of water is often underestimated even more so when is used in the generation of power and the potential energy that can be devastating if uncontrolled. This would be the story in a town in northern Italy when the effects of a landslide would cause a monumental flooding incident. I think this is the first time that we've covered an incident in Italy so salve. Today's disaster is tragic as the loss of human life was so sudden and dramatic. The disaster at the Veyant Dam could have been avoided however improper surveys and lack of proactive action led to a disaster over topping. Today I'm going to rate this subject here on my plainly difficult disaster scale. One of the tallest dams in the world sits disused at the foot of Monte Tocque 60 miles north of Venice. The structure hoped to offer clean energy for the northern region of Italy taking over 30 years from conception to construction. A time in which spanned a world war and several political changes in the country. When the construction was completed in 1960 a shocking disaster was not on the minds of the workers when they congratulated themselves on the monumental project just three years later. But how could an engineering marvel turn into a living nightmare? The first seed of a dam in the Veyant Gorge was traced back to the 1920s. However a couple of little known world events got in the way of the construction plans and work would begin in the 1950s after one of the little known events and a drastic government change of sorts was undertaken. SADE operated with Monopoly in the region. Ground was broken in 1956 in the Veyant Torrent with works being mostly completed by 1959 with inauguration in 1960. During construction works the project's license was extended to allow the dam to be raised by an additional 61 meters from the original plans making it the world's tallest dam at the time. In doomsow increasing the retention capacity to 169 million cubic meters instead of the 58 million cubic meters originally envisioned. The design of the dam made use of a double curve arch made of concrete 261 meters high with a width of 160 meters. Intended to provide as much electricity as possible the structure impressively loomed over the village of Longaroni. Longaroni was a small town on the banks of the Piave River. Its history goes all the way back to its establishment of a municipality in 1806 however the settlement's history goes all the way back to the Middle Ages. Geological studies had been undertaken in the area as early as 1928 with further studies in 1948 and more warringly close to construction 1957. In August of 1957 a vulnerable zone was identified hinting at the risk of a landslide along the banks of the soon-to-be-filled reservoir. Warringly nearby Montetocque was given the nickname the mountain that walks due to its known instability in the area. A local newspaper highlighted the local fears and legal action was taken against it for spreading false news and disturbing the peace. The basin began to be filled in early 1960 and within a couple of months small earth movements were recorded. A landslide was recorded in November when the reservoir was at a depth of 600 feet or 190 meters at an elevation of 645 meters releasing around 800,000 cubic meters of material into the lake. The water level was decreased to a depth of about 450 feet or 600 meters of elevation and more investigations into the stability of the banks were launched. Between 1961 and 1962 tests were conducted on a 1200 scale model of the dam. The results led to a maximum filling elevation of 700 meters being set for the dam. Once again the lake was filled in 1962 up to a limit of 700 meters of elevation and once again movement was recorded in the banks and local residents reported cracks appearing on homes. Again the water level was decreased stopping the seismic activity. During 1963 the dam was filled above its limit at 750 meters and again the land around the dam and reservoir became unstable with land shakes and movements of up to 1.2 inches per day were recorded and this number was increasing daily. The dam's ownership changed from a privately owned monopoly to a government-owned company named ENEL. The higher water level was exasperated by large levels of precipitation during the summer which also fed into the banks instability. Worried the operator decided to load the reservoir level again but this proved slow work. By September daily ground movements had increased to around 8.5 inches. A road that ran along the lake had deformed beyond use and by October disaster was inevitable with Monty Dock's south side collapsing with movement at around 1 meter per day. On the 9th October around 10.30pm the land slip began. Over 260 million cubic meters of earth and rocks slid down the mountain at speeds of near 90 kilometers an hour creating a deafening roar as the material hurtled towards the lake. The water level at this point was at 700.4 meters of elevation just above what was thought to be a safe depth to prevent overflowing of the dam. The land slip cut off the electricity supplied to Longaroni plunging the doomed town into darkness. As the massive material from the mountain entered the reservoir it displaced the water within creating deadly tidal waves. It was predicted the volume of the slide was about twice the volume of the water held behind the Vellante Dam. A wave 150 meters high violently topped the dam flowing into the valley heading towards Longaroni. Powerful air streams first hit then the water and massive rock and mud flowed through the town decimating everything in its wake. Between 1900 and 2200 people were swept away by the uncontrollable flow. As seen here in these before and after photos the massive material had flattened Longaroni which was once a vibrant town was now a flat plain of mud. The dam itself was largely intact apart from a few outlying buildings for electrical management and control. The main structure had only minor damage to the top of its masonry. The destruction was inconceivable and the cleanup efforts would run into millions of man hours and even more in Lyra. Over 10,000 people were mobilized for the recovery and cleanup efforts led by the Italian army and many were volunteers. The works utilized hundreds of vehicles including bulldozers, helicopters, trucks and other construction equipment to try and recover any survivors and bodies. Around 73 people were saved from the waters and rubble. Some 1600 drowned bodies were found with only around half of them eventually being identified. It is thought that around 350 families were entirely lost leading to the many unidentified victims. On Sunday the 13th October a mass ceremony was held for the endless line of coffins. The site was selected on farmland nearby. In hindsight the dam should never really have been built where it was due to the large instability of the region and unfortunately the alarm bells were duly ignored. Even at a fraction of the reservoir being filled instability was recorded but unfortunately like with many construction disasters once enough money has been spent on a project it has to be completed even against the evidence screaming the opposite. On 11th October 1963 an investigation commission was appointed to determine the cause of the catastrophe and to find out who was responsible. This led to 1968 and on the 20th February the assigned balloon or magistrate summoned 11 individuals to stand on trial on counts of negligent manslaughter due to the disaster being preventable. Three were died before sentencing with the remaining eight mostly being acquitted due to lack of evidence. However the lead engineer was sentenced in 1977 to five years of jail time although this was later reduced to one year. On the 15th February 1997 the balloon old civil and penal court sentenced a private company who originally built the dam to compensate the town of Longaroni for damages totaling 55 billion lira covering property, non-property and moral damages plus another 526 million lira for fees. Longaroni was rebuilt with a population today of around 4,000. A pumping station was installed to keep the reservoir level low and a bypass tunnel was installed for water to flow around the dam. Although still in situ the dam is unused for its original purpose. The disaster highlights that it isn't always the dam itself that can fail but everything else around it and at the yont it seems that it was the right dam but in the wrong place. I hope you enjoyed the video if you'd like to support the channel financially you can on patreon from one dollar per creation and that gets you access to votes and early access to future videos. I have youtube membership as well from 99 pence per month and that gets you early access to videos as well. Check me out on twitter and also if you'd like to wear my merch you can purchase it at my Teespring store and always have to say yes thank you for watching. In the same year that a reactor in the UK set alight another fire in the nuclear industry took place in the rocky flats plant in the US. The event would go on to be relatively unknown until another fire at the same site was discovered 10 years later. September 11th is a date that has become part of world history however today's subject isn't the 9-11 that normally springs to mind. Instead a fire in a glove box in a plutonium process building will be the focus for this video. I'm going to rate today's subject matter here on the plainly difficult disaster scale. Located in golden Colorado around here on a map the rocky flats plant is situated on 384 acres inside a 6,550 acre nature reserve. Ground was broken in 1951 for a new site to build vital parts for the budding nuclear weapons industry in the United States. The construction work in a Pittsburgh press article was estimated to cost around $45 million. The AEC appointed Dow Chemical Company as the plant's operator between 1952 and 1975. The main goal of the site was to produce plutonium pits which form part of the trigger to an atomic bomb. A pit is a hollow plutonium sphere that is imploded creating an explosion that triggers the rest of the weapon. The demon core was a plutonium pit however it wasn't hollow but instead had two spheres with a ring in the middle. The site produced its first pit in 1953 and over the remainder of the 1950s would grow to 27 buildings. The facility manufactured most of the triggers for the US atomic weapons stockpile. That was until 1993 when production was abruptly ended. The pits were formed from plutonium buttons which looks pretty much how it sounds as seen here. From buttons the plutonium was formed into the hollow sphere needed for weapons production via foundry and machinery work. Although a vital part in the weapons production process, Rocky Flats was only a link in the manufacturing chain. As once the pits were created they were sent off to the PanTechs facility near Amarillo, Texas. Not only did the facility deal with plutonium but also uranium and beryllium as well as myriad of chemicals including carbon tetrachloride used as a cleaning solvent in the manufacturing process. The production buildings did not have fire suppression systems due to the risk of criticality incidents caused by water forming a moderator but instead the buildings were fitted out with little combustible material as possible and this seemed to work in a 1955 chemical explosion which was effectively dealt with. This brings us on to September 11th 1957 and building 71 which was used in the process for pit creation. As a side note building 71 was the first production building at the site. Room 180 contained glove boxes used to protect operators from the radioactive isotopes. Some of Rocky Flats were up to 20 meters in length with multiple lead line gloves used to manipulate the tools needed for machining and forging. The boxes were made of stainless steel, had reinforced plexiglass windows and had Benalex shielding made of wood fibre and plastic to protect operators from neutron radiation. Extraction fans were provided to vent air from the glove boxes to prevent any release of radioactive dust. Multiple filters are provided on route for any material before it goes to building 71's vent stack. The ventilation system was equipped with heat sensors which were intended to switch off the fans preventing the spread of a fire which is great however this had been disabled due to false trips slowing down production. Plutonium can be a fire hazard if handled incorrectly or not stored in a dry environment. If in too high of a humidity room the plutonium can form hydrides on its surface which are pyrophuric and may ignite in air at room temperature. This risk increases when the material is finely divided for instance in dust. Such a spontaneous combustion can be a deadly event with the potential to release radioactive particles. At 10pm this such incident began as a small amount of plutonium turning spontaneously combusted spreading the fire along the plexiglass. 10 minutes later the fire was discovered the cooling fans were powered up to protect the firefighters from contamination as they attempted to use carbon dioxide to quell the flames. However this spread the hot plutonium dust into the filtration system something that the heat sensors should have prevented however this was disabled. Plutonium burns in a similar fashion to charcoal however the smouldering was a perfect ignition source for the highly flammable plastic within the glove boxes. After this failed and faced with an ever building up fire the firefighters used something that they really shouldn't have been using when dealing with plutonium and that was water at 10.38pm. Although it initially stopped the flames which were from the burning plastic and other flammable materials inside the boxes the moisture reached the plutonium increasing its heat. There was also a massive risk to achieving a criticality accident as the water would help sustain the chain reaction. The air filtration system itself posed risk as the heat and moisture spread upwards by the fans. Ever since building 71 was first pressed into service the filters had not been replaced and were filled with plutonium dust which was much more susceptible to moisture. A minute after water was introduced a loud blast was experienced. The force bent a plenium steel frame in doing so spreading the fire into the filtration system. The explosion also destroyed the cap at the top of building 71's smokestack. On order of the health physicist's supervisor everyone evacuated building to escape the plutonium contamination which by now had spread throughout building 71. At 10.45pm fire was now discovered in the vital filter banks on the second floor the only thing preventing widespread contamination of radioactive particles released from the fire. As the fire burned contamination spread out from the damaged smokestack engulfing the surrounding area. At 2am the fire was declared knocked down however it wouldn't be completely stopped until 11.28am on the 12th September. It was estimated that around 63kg of plutonium was present in room 180 at the time of the fire with 13-21kg being involved directly. It was estimated that around 500g of plutonium 239 and 240 was released into the atmosphere. However due to lack of proper monitoring and almost immediate cover up these figures are an educated guess at best. The contamination was spread by winds and some was deposited in the soil. The material is dangerous once ingested due to plutonium being an alpha particle emitter. The highest risk of exposure of the local population was the persons who were exercising or were working outside in areas where the plume of plutonium particles was near the ground. However some of the most at risk were the firefighters who for nearly 13 hours were exposed to the deadly plutonium. The highest dose was estimated to be 15mrems off site. The blaze heavily damaged building 71 necessitating the installation of an incinerator in 1958 to dispose of the amount of contaminated material. Elements such as strontium 90 and cesium 135 were detected as a result of the fire hinting at a criticality event. However officials denied that such event had occurred. The public wouldn't be aware of the incident for just over a decade until a second fire also involving plutonium was fought also using water. The only reports of the incidents in local newspapers claimed that none was injured and no release of radioactivity was recorded and the damage costs were estimated to be around $50,000. The cleanup of building 71 started as soon as the fire had ended. Work resumed on a limited scale before the end of 1957 but cleanup efforts would be continued all the way until early 1962. The building would be pushed back into service being renamed 771 with the whole site continuing to produce plutonium pits until 1993 when production was transferred to Oak Ridge National Laboratory. This was only after the site was raided by the EPA and FBI in 1989 after numerous reports of staff relating to deadly working conditions. Really the incident in 1957 is only scratching the surface of this radioactive dumpster fire of a place. Now don't worry I'll be doing another video soon about the 1969 fire and its wider impact on the site and also Rocky Flat's ultimate demise. I hope you enjoyed the video. If you like to support the channel financially you can on Patreon from $1 per creation and that gets you access to votes and early access to future videos. I have YouTube membership as well from 99 pence per month and that gets you early access to videos as well. Check me out on Twitter and also if you like to wear my merch you can purchase it at my Teespring store and all that's left to say is thank you for watching. In the cold winter of December 2001, three villages in Lea, Georgia found two strange objects, warm to the touch and apparently abandoned in the snow. Thinking they were heaters the men used them to keep warm during the winter night. Little did they know that these unlabeled objects contained around 1,295 tB of radioactivity. Radioactive isotopes have been used for a variety of tasks apart from the two obvious ones. For example in radiotherapy, sterilization and industrial inspections. Today's subjects like many orphaned sources on this channel show the deadly ramifications of improper storage and disposal of radioisotopes. And again like many other stories it would be some unwitting locals that would fill the brunt of such improper disposal. With two needing specialist medical care in Paris and Moscow respectively, one of whom would sadly pass away. Thus I'm rating it here on the plainly difficult disaster scale. Georgia, the country not the state, is in the Caucasus region of Eurasia. The country's neighbours on its southern borders are Turkey, Azerbaijan and to the north is Russia. Lea is a village located approximately 320 kilometers northwest of Tbilisi, the capital of Georgia. We'll come back to Lea in a bit, but first we need to look at what a radioisotope thermoelectric generator is. The Soviet Union employed three types of radioisotope thermoelectric generators also known as RTGs. Serium 144 with an activity of 740 terebecules, cesium 137 with an activity of between 1800 and 5500 terebecules and finally the strontium 90 with an activity of up to 3700 terebecules which is the subject of today's videos. In terms of nuclear energy, these generators are relatively simple in design, which makes sense where they would be just left in the wilderness somewhere, expected to reliably provide power day in day out for years. In the most basic form an RTG turns heat into electricity by heating up a thermal battery creating chemical energy, which then when discharged produces electric energy. Strontium 90 decays by beta emission. In doing so releasing significant heat needed for electrical generation. The isotope is well suited to this application due to having a half-life of around 28 years. Strontium 90 is also attractive as it is cheaper than plutonium 238 and is created during nuclear fission. The beta M type was a strontium 90 power generator designed to last up to 20 years and are intended for low power applications such as navigation or radio relays. Which is what the ones at Lear were for. After manufacturer the generator is capable of generating 10 watts of electricity from 250 watts of heat with 1480 terebecules of radio activity. The unit strontium 90 was contained within a tungsten shield. On top of the strontium 90 was the thermobattery which generated the electricity. This was surrounded by a heat shield which was then in turn surrounded by an outer radiation protection shield. Topping off the unit was a heat dissipator. At Lear, two RTGs were used as part of a chain of radio relays between the Kuduni hydroelectric plant and the Nguri dam which were installed in the 1980s. This was for contact between the two plants during Kuduni dam's construction. Four substations were installed each containing two RTGs between the two hydroelectric plants. Beta-M's were usually installed in pairs and were capable of powering a lightbulb. Which doesn't sound like a lot however for radio relays not a large amount of electricity is needed. However it is needed for a long period of time. The generators totaling eight were abandoned in situ. By the 1990s most of the generators were disassembled, exposing the radioactive sources and removed from the original locations. The first of the sources were discovered in 1999 and a second pair were later found on in the same year. A third pair would be found in 2001 and that would be near Lear. Now a lot of this timeline comes from the IAEA report into the incident and it goes into a lot more detail when I can fit into this video so it's worth checking out after watching. On the 2nd December, three men residents of Lear were searching for firewood around 45 to 50 kilometres east of their home. While searching at around 6pm the men found two cylindrical objects lying on the ground melting all the snow within a 1m radius. The wet soil near the objects was causing steam. One of the men picked up the objects and dropped it almost immediately due to the heat. With the winter night drawing in, the men decided to sleep in the woods making use of their new found sources of heat. The two objects were manipulated to the campsite using wire to lift them, however at least two of the men had handled the items personally. A fire was set up for dinner and the men sheltered in for the night. After dinner the men drank some vodka but felt unusually sick and dizzy. Within 30 minutes all three men had vomited. This was after a couple of hours of exposure to the mysterious objects. The vomiting lasted for the remainder of the night and by the morning the three exhausted men only collected half the wood intended into their truck and made their way back to Lear leaving the two devices behind. The first of the men reported to the doctors a day after of repeated diarrhea on the fourth. He didn't mention to the doctor the strange object that he had encountered instead getting treated for intoxication. Eight days post-exposure, another man reported to the doctor after developing eurythma, a burning sensation and odema on the right hand, leaving one of his hands immobile. By the 17th of December all three men had developed some kind of skin irritation on either their backs or hands. Five days later all patients were hospitalized in Zugdidi, Georgia. The three patients were diagnosed with acute radiation syndrome and the case was reported to the emergency medical center in Tbilisi. A day later on the 23rd of December all three were transferred to the capital city. But for now we'll put their story on pause and look at the recovery operations. Also on the 23rd of December the Georgian authorities attempted to locate the two objects that had caused the ARS symptoms in the patients. This did not yield results as the forest roads had become impassable due to the worsening weather condition. Not working from a background of experience with orphaned sources the Georgian government requested assistance for the removal activities from the IAEA. A second attempt a few days later on the 29th was successful and initial investigations into the condition of the two sources was undertaken. They were found just off a dirt track 28 kilometers from Lia with the immediate vicinity blocked off by boulders from the landslide. Now that they were located in order to recover the sources several things had to be prepared but the next few weeks the following was arranged. A container fabricated locally made of lead 27 centimeters thick, 90 centimeters high weighing in at 5.5 tons. Special steel remote handling tools and tongs to collect the radioactive sources were manufactured, an old army truck to transport containers adapted and 26 soldiers were trained to recover the radioactive sources. Not only that but the recovery attempt needed food supplies for two days, fuel for 12 vehicles and field accommodation for up to 50 people. The boulders and rocks had acted as a partial shield and as such initial recordings of radiation were at 1.3 millisieverts an hour. This was handy for the recovery team as it allowed them more time to prepare the area for extraction. A maximum dose was set to be 10 millisieverts per member of the recovery crew. Between the second and third of February 2002 the recovery operation was undertaken after arriving at the site preparatory work and measurements took around 30 minutes. The actual recovery only took 20 minutes, that was from the first movement to loading into the containment vessel. The truck took around 3.5 hours to return to the nearest village, as you can see from these pictures the roads were hardly a newly laid motorway. The highest dose rate for the recovery team was recorded at 1160 microsieverts. Measurements above the container with the lid off after recovery was recorded at 4.6 severts an hour. After all the container caps were placed on the top the dose rate was reduced to 12 to 14 microsieverts an hour, a safe transportation limit. Right let's get back to the victims of the incident. On the 23rd of January 2002 the first patient was discharged from hospital care under outpatient supervision. His exposure was significantly less and resulted in mainly injuries to his hands and arms. For the remaining two the journey would be long and painful involving specialist care far away from home in Lear with only one making it back. The two remaining patients had severe burns on their backs as they had slept up against the sources leading to an increase in exposure. On the 31st of January the IAEA was contacted for advice on specialist treatment for the two remaining victims. This resulted in one being admitted to the Institute of Biophysics of the Burner Zion Federal Medical Biophysical Centre in Moscow and the other admitted to the Burn Treatment Centre of the Percy Military Training Hospital in Paris for further treatment. The patient said the Paris was in relatively good health at the time of the exposure. The burn sections of his body luckily didn't have too deep necrosis. The affected area more than 8% of his total body surface had received more than 20 to 25 greys. It would take five skin grafts and multiple necroptermies to reach a favourable recovery. Over 502 days after exposure multiple skin grafts and being treated for coutaneous radiation syndrome the second patient was discharged from Paris in March 2003. The patient sent to Russia was estimated to have received a total dose of radiation to the left side of his back at around 25 to 35 greys. The burn area was most of the patient's back leaving scarring and blistering eventually leading to necrosis. Several attempts at skin grafts were undertaken each time resulting in failure to acclimatise and even more necrosis of the skin necessitating removal of the dead skin leading to the requirement of more skin grafts. After each attempt the affected area increased after 893 days post exposure and experiencing a deteriorating condition and multiple traumatic surgeries the patient died due to cardiac arrest. The patient's chances of survival were greatly reduced due to him suffering from TB at the time of his exposure delaying treatment of the ARS. The incident like many other orphaned sources showed the risks of improperly disposed radioactive items. What is worrying about Leah is that at the time of the IAEA report into the incident only six of the eight original Beta M radioisotope thermoelectric generators have been located meaning two more lay waiting to be discovered. It is thought by the IAEA that at least 1000 such RTGs are in Russia or any of the ex-soviet union countries. Many parts are working life albeit useless for original purpose but are still deadly if improperly handled. Each one left out in a wilderness somewhere is another Leah waiting to happen. Hope you enjoyed the video? If you like to support the channel financially you can on Patreon from $1 per creation and that gets you early access to votes and early access to future videos. I have YouTube membership as well and from 99 pence per month that also gets you early access to videos. Check me out on Twitter and also if you like to wear my merch you can purchase it at my Teespring store and all that's left to say is thank you for watching. The chemical trichlorophenyl has multiple uses from fungicide to antiseptic and even hexachlorophen creation. Manufacturer of this chemical compound involves many deadly chemicals one of which dioxin would plague a small town in Italy. When I was watching one of my new found favourite comedy shows I saw a few references to a chemical disaster in Cervezzo and this led me down a research wormhole. Cervezzo is an Italian town in northern Italy 13 miles north of Milan and in the mid-70s had a population of around 17,000 people. Ultimately this population would be the largest to be directly exposed to dioxin. Today I'm going to rate this disaster here on my plainly difficult disaster scale. ICMESA was a factory located near the town of Meda, a subsidiary of Swiss-owned Hoffman La Roche. The factory began manufacturing 245 trichlorophenyl from 1971. B department at Meda Plant manufactured TCP which was subsequently transported to another site to produce herbicides and antiseptics. You might be wondering why the event wasn't called the Meda disaster. Well the answer is pretty simple as it was Cervezzo who got the brunt of the balls up at the plant. Let's have a look at the manufacturing process and how the deadly dioxin chemical got involved. You see, dioxin is a byproduct in the manufacture of trichlorophenyl. It is formed by condensation of two molecules of 245 TCP. The unwanted bribe product is limited due to the temperature needed for the trichlorobenzene and sodium hydroxide reaction to around 160 degree centigrade. As a disaster would later prove higher temperatures in excess of 180 degree centigrade would create more of the unwanted dioxin than the usual minimal amounts. Reactors used on site were equipped with stirrers to mix the ingredients and their solvents and a condenser used to eliminate the water in the condensate and to feed xylene back into the reaction. Each 10,000 litre reactor was made of chromium nickel molybendium alloy and were heated with steam and cooled with water. The steam was at a pressure of 12 bar and came from the exhaust from an on-site electricity generation turbine. The temperature of the incoming steam didn't have a thermometer meaning that the operators could only monitor the overall reactor temperature. A rupture disc leading to a roof vent was provided with a tear pressure of 3.8 bar to protect the reactor from over pressure. The reactors were equipped with a large cooler and had a 3000 litre reservoir of water ready to flood the contents if needed. One big issue with the setup was that the reactor was not equipped with a temperature alarm and cooling could only be started manually meaning the system was not fail safe. This will become apparent later on in our story. For the process the mede plant mixed solid sodium hydroxide 1,2,4,5 tcb, ethylene glycol and xylene using the reactor stirrer. The initial reaction mixture was heated at 170 degrees Celsius using steam from the plant's turbine. The mixture was kept at this temperature for around six to eight hours. After this distillation of the mixture took place between three to four hours to recover clean solvent for use later on in other work. Once distillation was completed 3000 litres of water was added to the reaction medium to bring the temperature down to between 50 to 60 degrees centigrade. The total process usually took between 12 and 14 hours start to finish. The contents of the reactor were then hydrolyzed with an aqueous solution of hydrochloric acid to release the trichlorofenol from sodium trichlorophenate. 10 hours later than usual on the 9th of July 1976 the 2,4,5 tcp production started at 4pm. The plant was to be shut down over the weekend and because of this the process was interrupted when only 15% of the solvent was distilled and crucially the final stage of adding water to reduce the temperature wasn't completed. Around 15 minutes later the stirrer was shut down leaving the reactor's contents to settle. The operator signed off at 6am leaving the reactor unattended. With the stirrer turned off and the mixture being at a low level the heat coil heated the air above the chemicals increasing the surface temperature of the steel liquid by at least 31 degree centigrade. The temperature reached 190 degree centigrade and started an exothermic reaction raising the pressure in the reactor. With no one monitoring the reactor and no automatic cooling system the exothermic reaction turned into an uncontrolled runaway. Eventually the expected would happen and the reactor pressure went past that of the 3.8 bar rupture disc. Upon surpassing the pressure the disc ruptured releasing a reddish cloud up to the chimney of the process building spreading its contaminants over the local area. An estimate of between 0.2 and 2kg of dark sin was released into the atmosphere which would eventually come down on the population below. The plume rose to a few metres above the ground and was spread southwest by the blowing wind. Luckily one of the plant supervisors was near the plant and rushed to shut the reactor down. The event went unnoticed until a day later when some children who had been presumably been playing in their gardens started to show signs of intestinal problems and high fever. Vegetables and crops looked burnt and several animals were affected. The ICMESA informed local authorities that a herbicide cloud likely to damage crops had been accidentally released. Two days after the release locals were told not to consume any products from their gardens but things would get worse. Four days post-exposure children in the area exhibited burns to the skin and local pets and animals started to die. Over the next few days several children were hospitalised however the doctors not knowing the cause were hindered in treatment. Until 10 days post-exposure the plant managers admitted to dioxin being present. After almost two weeks of exposure to the local residents it was decided to evacuate the area affected by the plume of the deadly dioxin. 11 towns were impacted and the areas were split into three zones. Zone A covered 110 hectares including Meda and Cervezzo and dioxin concentrations greater than 50 micrograms per meter. 736 residents of this zone were evacuated by the end of July. Zone B covered 270 hectares including Cezano, Moderna and Deserio had dioxin concentrations between 5 and 50 micrograms per meter squared. In August all pregnant women and children under 12 had to leave the area during the daytime to reduce exposure. All agricultural activities were also prohibited. Zone R or Compliance or Caution Zone consisted of 1400 hectares where dioxin was detected in trace quantities and farming was restricted. Around 2000 hectares of soil was contaminated and over 80,000 animals died either directly or due to the liquidation works. Short-term effects on the human population was primarily burns however long-term effects were chlorachny, cancers, respiratory issues and diabetes. As a side note chlorachny is a pretty nasty condition as it causes an acne-like symptoms on the skin usually around the face, neck and armpits. The condition is particularly resilient to treatment and can persist to up to two years if you're lucky or unlucky lifetime. Not only the physical effects of the disaster were seen in the local population but also the psychological toll. Adding into this was the economic damages to the area. All activities were prohibited in Zone A a decision affecting two industrial companies, 37 cottage industries, 61 farms and 4,000 kitchen gardens all of which would have to be abandoned. The cleanup efforts in the region would take five years. All of the contaminated soil, construction waste and animal dead bodies were buried in Zone A in two sealed containers. In total 200,000 cubic meters of material was removed and buried. In July 1977 over 500 residents of Zone A were allowed to return home and Zone R was allowed to resume agricultural operations. The ICMESA plant was demolished in 1982 and waste materials were put in barrels designed for radioactive waste for incineration in Switzerland. Anything of value was removed for decontamination and later reuse. All remaining waste was buried in a container on site. The land would later be reused eventually turning it into a local sports centre. Zone A and Zone B were declared cleaned up allowing construction in 1984 essentially calling the end to remediation works. 1983 saw the legal ramifications from the disaster. Senior management of ICMESA was given a suspended sentence of two and a half to five years. The disaster's cause was down to quite obviously operator negligence as the reactor was left unattended mid-cycle. Even though this was the case knowledge on the formation of darksin was somewhat limited as such a disaster was thought not to be possible. You see in the 1970s scientific literature said that decomposition of the reaction mixture was 230 degree centigrade but the literature was proving to be out of date as multiple darksin forming incidents had happened in the early 1970s. The critical temperature proved to be closer to 180 degree centigrade for a weak exothermic reaction leading to a more serious runaway reaction. Hope you enjoyed the video. If you'd like to support Channel Financial you can on Patreon from $1 per creation and that gets you early access to videos and access to votes on future videos. I have YouTube membership as well from 99 pence per month and that gets you early access to videos as well. Check me out on Twitter and if we want to wear my merch you can purchase it at my Teespring store and all that's left to say is thank you for watching. Imagine spending loads of time and money on building a nuclear reactor only to intentionally destroy it. Well imagine no more because of course the US has been there and got the t-shirt. In 1964 and 1965 two nuclear reactors were prepared to be deliberately pushed beyond their limits to destruction. The Snapdragon series of tests involved testing a reactor for use in space travel and as such the experiments would be a vital stepping stone. The test in 1964 would involve submerging a reactor in water in order to simulate an aborted launch and subsequent ditching at sea. The test in 1965 would push the reactor out in the open simulating a crash in the desert. Today we're looking at the Snapdragon reactor tests and although it didn't injure anyone or cause massive destruction purposely pushing a unit beyond its limits is interesting all the same and as such I'm going to rate it here number two on the plainly difficult disaster scale. NASA wanted to be the first to have a nuclear reactor in space and as part of its snapshot program. However our story starts in 1950s and the need for high power consumption spy satellites. In 1951 the US Atomic Energy Commission requested nuclear power plant studies to see if a reactor could be sent into space. By 1952 it was thought feasible although a series of test reactors would need to be built and destruction tested much like the HTRE project the AEC contracted two separate companies to work on two different concepts. Both sides of the project fell under the SNAP or systems for nuclear auxiliary power name. The first numbered in odd numbers starting with SNAP 1 employed a simple by nuclear standards RTG design using decay heat from a radio isotope to generate electricity. The concept was much the same as the RTGs that caused the issue in Lear using a thermobattery or thermocouple to transfer the heat to electrical power. This side of the project was contracted out to the Martin company and would continue on to SNAP 27 which made it all the way to the moon. Although interesting in concept it's the even numbered SNAP test units which are our focus today and they were much more complex in design as they were a fully fledged nuclear reactor. This part of the project was contracted to Atomics International Division of North American Aviation. The first reactors developed by AI was SNAP 2 and was developed to SNAP 8 and then finally 10A which was the first space ready type built by the company. The SNAP 10A consisted of a 15.6 inch long by 8.8 inch diameter tube holding 37 fuel elements. The reactor once in space was expected to produce a minimum of 500 watts of electricity for up to one year or even longer. Around the outside the core fixed beryllium blocks were employed to reflect neutrons back to the core. What's interesting about the design was that control rods were not employed. Instead additional beryllium reflectors were mounted to four drums which could be rotated towards and away from the reactor. With the reflector side facing the core allowing a chain reaction and a reflector facing outward shutting down the reaction. Two of the drums were used to step up the power during startup. Upon launching into space a startup command was sent to the reactor. A pin was released by actuators and two control drums were immediately inserted and the fine control drums would then be stepped in. 50 seconds after the startup command the two fine control drums would take their first step and would continue to step in every 150 seconds until fully inserted. Approximately seven hours after startup criticality was reached and would take around 72 hours for the fine control drums to reach the end of their steps after which the reactor ran at a steady state of power without dynamic control. The reflectors were held in place by a retaining band and could buy an explosive bolt. If needed the bolt could be blown removing the reflectors from the core shutting it down. The reactor had 4752.5 grams of uranium-235 as uranium zirconium hydride fuel which were contained within the 37 fuel rods. Sodium potassium alloy was used as a coolant for the reactor design and was circulated through the core and the thermoelectric converters by a liquid metal pump. The converters would thus provide power for the satellite. Before NASA would allow the 10a for launch a number of destruction tests would be needed to be conducted to simulate the potential situations the reactor could be subjected to. For example being dropped into the sea or crashed into the desert. Before any radiological tests several unfuelled 10a reactors and its components were stress tested in every imaginable way. This leads us on to the SNAPTRAN experiments. The TRAN stood for transient. SNAPTRAN 1 and 2 experiments were intended to investigate nuclear excursions occurring in an atmospheric environment during assembly or launch caused by unwanted movement of the reflectors. Second of which were nuclear excursions resulting from immersion of the reactor system in water or wet earth. This would become the SNAPTRAN 3 experiment. The tests would be undertaken by Philips Petronium at the initial engineering test IET facility at the National Reactor Testing Station at Idaho National Laboratory. The first of the experiments unsurprisingly named SNAP1 was a non-destructive test and used a modified 10a to subject the reactor to sudden changes in reactivity. The reactor assembly was mounted on a four-track test dolly that was constructed from two railway carriages. The initial non-destructive tests took place under a corrugated structure that was also mounted on the tracks. All operations were conducted by a nearby underground control room. For the test to be undertaken the reactor had its drum control modified splitting the four drums into two pairs of two. The first pair were the impulse drums and were intended to create sudden impulses of power by quickly turning the reflector side to the reactor core. The second pair were stepper drums and were intended to gradually increase power to test a much slower rise. The experiments made use of both drums and their respective form of movement to collect basic kinetics data for a wide range of transient conditions. The test began in May 1963 and according to a scheduling report from before the experiments would run until 1965 however SNAP2 wouldn't be conducted until 1966. The first destructive test was the SNAP3 and would simulate a launcher brought into the sea. There was a problem with this test as it wouldn't yield usable data by just dumping the reactor in a body of water and instead the designers thought up an ingenious way to immerse the unit. The reactor was permanently mounted in a fixed position and provision was made for water to be rapidly placed around the test unit before the reactor was allowed to reach criticality. Earlier non-nuclear tests showed that upon impact with the water it was likely that the beryllium reflectors and other external components would be separated from the unit because of this it was decided that only the reactor core would be destruction tested in water. The reactor vessel fully fuelled up would be mounted on a pedestal inside a 14 feet diameter open tank rigidly mounted to two railway flat carriages similar to the one used in the SNAPTRAIN 1. The tank was surrounded by concrete one foot thick on the sides and two foot thick on the bottom. Due to not having the reflector drums installed a different form of power control was needed and this was provided by a poison sleeve actuated by a drive mechanism which could be fully withdrawn either slowly or rapidly as well as providing a scram facility. Intermentation was installed nearby as well as several miles away from the test site to gain information on the amount of radio activity released into the environment. Before the destruction test a number of calibration tests were undertaken and this used a calorimeter tank which can be filled with water after which the poison sleeve can be slowly raised until criticality is attained. During the calibration test the reactor operated at low power levels but a destructive test the calorimeter tank was removed and on the 1st of April 1964 operators at the NRTS prepared to purposely destroy a reactor. The sleeve removal mechanism was fired removing all poison from the reactor. The reactor experienced a sudden power increase to $3.60 above critical. Within milliseconds a Cherenkov glow was masked the reactor and after 20 to 30 milliseconds the reactor experienced peak power. The power increase caused the reactor to blow apart. All 37 fuel elements and six beryllium reflectors were destroyed and a 40 foot high plume of water was blown out the top of the tank. The reactor was well and truly destroyed with debris scattered all around the tank. It was calculated that the reactor experienced a peak power transient of around 13,000 megawatts. All the parts and debris of the reactor were loaded onto a flatbed railway carriage and were shipped off to a hot shop for dissection and analysis. A radiation detector 20 feet away recorded 30 runkens per hour at the time of the peak power excursion. Decaying to 0.055 120 minutes after the test and 24 hours later was at 2 milli runkens per hour. Trace amounts of the following isotopes were found iodine 131, 132 and 133 and strontium 89 and 90. Right that leads us on to Snapdragon 2 and the beryllium reflected destruction test. This was to be conducted on 11 January 1966. After the initial non-destructive test yielded satisfactory results the next step was to ramp up the stress on the 10A and undertake reflector criticality destruction tests. The purpose of Snapdragon 2 was to find out total energy release, mode of shutdown and a degree of fission product released during the destruction of a 10A reactor in open air. The reflector drums returned for this test for control of the reactor. For the test a new similar core to the Snapdragon 1 was used although some minor modifications were undertaken including a minor change to fuel weight and alterations to the way the drums were shimmed. Although the main change was the removal of the reactor's knack coolant this was done to allow high-speed cameras to observe the reactor core more easily. For this test the corrugated metal structure was wheeled away from the reactor to monitor the spread of radioactivity and the grid was set up to track any fission product releases. Film badges, fallout plates, pocket dosimeters and nuclear accident dosimeters were used for monitoring. On January 11th 1966 after early morning preparations the reactor test pad and downwind areas were cleared of personnel. At 9.51am the test was initiated as all four brilliant sides were inserted facing the reactor core achieving peak reactivity reaching 74,000 megawatts but only for a few milliseconds before total destruction of the core. A visible smoke filled cloud arose immediately as the fuel burned and the reactor core blew itself apart around four seconds post peak power. 300 meters downwind from the reactor a rate of 2.7 runkins per hour was recorded. At 6 meters from the epicenter radiation was measured at 18 runkins per hour two hours post event eventually dropping off to 0.2 runkins an hour 48 hours later. Fuel pieces were found up to 100 meters away and debris from the beryllium reflector littered the test ground. In this before and after view of the reactor obviously not much was recoverable but in a test like this I assume that was considered a success. Familiar faces of strontium 90 and iodine 131 were found post test. Again like before all the reactor pieces were collected and sent to a hot shop for dissection and on the whole the test went well. The data from all three tests were vital in being able to predict the environmental and radiological consequences of the reactor being crashed onto our planet. The snaptran two tests seemed a little redundant however as the snapshot program had already launched the 10a reactor into space by April 1965. The actual reactor was successfully delivered to space marking the first to ever reach such a height. Although the experiment sadly failed 43 days later when a voltage regulator failed shutting down the reactor. The reactor was then left on a 1300 kilometer earth orbit after it shut down and will be up there for an expected duration of 4000 years. I hope you enjoyed the video. If you like to support the channel financially you can on Patreon from $1 per creation and that gets you access to votes and early access to future videos. I have YouTube membership as well from 99 pins per month and that gets you also early access to videos. Check me out on twitter and also if you want to wear my merch you can purchase it at my Teespring store. Not what's left to say is thank you for watching. The process of manufacturing aluminium oxide creates large amounts of toxic material called red mud. A plant in Hungary will experience a dam failure at its red mud reservoir and will result in death and pollution in the local area. Once the historic frontier of the Roman Empire the Danube River would once again receive contamination from an industrial disaster. The other being the Bayamare side-eyed spill. Today we're looking at the Aika Alumina Plant spill and you only have to look at these pictures to know that this one was pretty deadly to the environment. Unfortunately events would unfold in a similar way to that of 2000 in Romania. I'm going to rate this subject here six on my patented disaster scale. The Aika Alumina plant is based in Aika, Veszprim County, Western Hungary. The Aika Alumina factory was originally founded in 1943 and the site achieved full production in 1947 after being taken over by the Soviets post-World War II. The plant was operated by Mao Hungarian aluminium after the mid-90s privatisation of the country's aluminium industry. It was one of the largest employees in the region and including its suppliers provided jobs to 6,000 people. The site used the Bayer process in the manufacture of aluminium oxide. First let's look at what the manufacturing process involves. The process was originally devised in 1888 by Carl Joseph Bayer, unsurprisingly which is where the name came from and was used to create Alumina from ore. The sediment rock bauxite contains a large aluminium content and as such is one of the leading sources of the metal. In order to extract the metal from the ore the Bayer process employs multiple steps before aluminium oxide is achieved. Initially the bauxite is milled and crushed, next it is placed inside a pressure vessel and a sodium hydroxide solution is introduced. The vessel and its contents are heated up to between 150 to 200 degrees centigrade. The aluminium dissolves into the solution at these temperatures forming sodium aluminate. The new solution is then filtered off taking off the red mud which contains calcium, metallic oxides and sodium hydroxide. This byproduct is stored in ponds but we will come back to this in a bit. The sodium aluminate is then seeded with fine-graded aluminium hydroxide crystals from previous extractions. Finally the newly formed crystallized aluminium hydroxide is then converted into aluminium oxide by heating in rotary kilns producing aluminium. Between 2 to 4 tons of bauxite is needed to produce just 1 ton of aluminium oxide. The waste byproduct red mud is highly alkaline and has an ingredients list of iron oxide, aluminium oxide, silicon dioxide, calcium oxide, titanium dioxide and sodium oxide. Not only these but the residues also contained levels of chromium at 660mg per kilogram, arsenic at 110mg per kilogram and mercury at 1.2mg per kilogram as measured by green piece in 2010. Because of this the caustic red mud can cause burns after contact with the skin and needless to say this is not good for wildlife if ingested. The plant produces 700,000 tons of red mud per year and by 2010 around 14.5 million tons had accumulated. The red mud wastes at Eicher were contained in a number of reservoirs on site where the water parts of the waste evaporate off leaving the mud behind. On the 4th of December 2003 the Hungarian Environmental Agency abolished the hazardous classification of the Eicher plant, thus Mao's red mud storage facility was no longer considered a hazardous waste reservoir. This meant that inspections of the reservoir dams were reduced leading to disrepair and reduced chance to catch any issues with the structure before it led to failure. Even though the plant was now considered not hazardous, concerns were raised about the plant's dam locally. The negligence to the dam would meet a summer of flooding and heavy rainfall known as the Central European floods of May and June 2010 and this would become the cocktail of deadly results. This leads us on to the 4th of October 2010 and reservoir number 10's dam failed on its northwest corner. The failure caused a halt in the dam 50 meters wide by 22 meters high. The breach released around 1 to 1.8 million cubic meters of strongly alkaline liquid red sludge, a surge of a 1 to 2 meter high wave drowned at least 10 people as engulfed nearby houses. Initially 40 square kilometers or 15 square miles of land was affected by the effluent staining all within its grasp with an orange red pigment. The nearby towns of Colantar and Devachare were the first to fill the brunt of the toxic tidal wave with cars being swept away and people's homes being battered. More than 300 families around 731 people would lose their homes as local authorities evacuated the affected inhabitants and the state of emergency was called. Due to the caustic nature of the spill, 406 people needed urgent medical care of which 120 were severely injured. The effects were mainly burns due to the fluid permeating the victim's clothes. Scarily the 4 effects of the burns could take several days to show on the victim's skin and could lead to deeper tissue damage if untreated. The red mud contaminated local agricultural land permeating the soil. The flooding eventually reached the Marcol river via the torna and by the 7th had reached the Danube. Croatia, Serbia, Romania, Bulgaria and Ukraine all enacted emergency plans in case of pollution to their sections of the Danube. Immediately Mao released a statement claiming the effluent was harmless and trying to downplay the release only claimed around 300,000 cubic meters had escaped. The company claimed it wasn't their fault and it was natural processes that was to blame. Even on Mao's best case prediction, in comparison only around 100,000 meters cubed of cyanide contaminated effluent was released in Bayamare. In addition to this, the company also blamed the past communist governments who had originally built the dam because why not? As part of the early attempts to stem the flow, emergency workers poured plaster into the Marcol river to try and bind the sludge preventing it from travelling downstream. On the 5th of October, one day after the breach, the government ordered the plant to cease operations and to rebuild the dam. By the 12th, the temporary stone replacement had almost been complete, with further flow control dams planned. The company started the plant back up on the 15th under government supervision. The path to remediation would take several years and over 100 million euro. Around 145,000 people would work on remediation in some kind of capacity. A year after disaster, normality had started to return with 112 houses built with state support. The trying to spare a catastrophic disaster in the Danube attempts were made to try and neutralize the alkalinity of the water in the Tauna and Marcol rivers. However, vegetation along the banks had all died. As much toxic sludge as possible was removed from the affected areas and returned to proper storage. The MD of Mao and a number of other company workers were arrested and charged with criminal negligence. Although, like we've seen before on this channel, they were released after charges were dropped. By 2013, Mao had gone out of business, with the Hungarian government completely taking over production on a gradual basis. The speed and relative low cost of the construction of the replacement dam hints that Mao could have easily prevented the disaster if a proactive approach to maintenance was employed. I hope you enjoyed the video. If you'd like to support the channel Financial, you can on Patreon from $1 per creation. That gets you early access to videos and access to future votes. I have YouTube membership as well, and that gets you from 99 pence per month early access to videos. You can check me out on Twitter, and also if you want to borrow my merch, you can purchase it at my Teespring store. And all that's left to say is thank you for watching. In 1926, engineers and construction workers congratulated themselves on the completion of the St Francis Dam. Little did they know, but two years later, the fruit of their labour would be rubble and over 400 people would lose their lives. Dam disasters are intriguing as the vast structures seem indestructible, as they hold back mind-blowing quantities of water. However, as we have seen many times before on this channel, engineers can and have got it wrong, and the results can be catastrophic. Today we're looking at the St Francis Dam and I'm going to rate it here 8 on the Painted Plainly Difficult Disaster Scale. St Francis Dam was located in LA County, California, USA, which is around here on a map. Our story starts with eventual superstar engineer William Mulholland. Starting off from more humble route, in 1878 he was hired by the Los Angeles City Water Company as a ditch tender. Proving to be a good employee, Mulholland raised through the ranks, eventually reaching superintendent. During his rise to power, Mulholland had become a self-taught engineer, studying in his free time. Being a bit of a future thinker, Mulholland envisioned an aqueduct to supply Los Angeles with water from 233 miles away in the Owens Valley. Plenty to allow the city to grow. Taken on as chief engineer, he oversaw the project during his construction between 1908 and 1913. The successful completion of the project, which at the time was the largest of its type, brought fame to Mulholland's door. Although clearly brilliant, Mulholland had the ability to improvise on the spot, which is why the aqueduct was built in a relatively short period of time, but sometimes this would come at the cost of shortcuts. He also had an eye for saving money, which is good for budgets, but not good for redundancy and design. To save money, his own staff performed all their own engineering calculations, without any external review. Although frugal and ultimately okay on the aqueduct, when it comes to dam design and construction, cut corners can cause, well, we'll find out later. By the 1920s, the demand for water in Los Angeles had outstripped Mulholland's aqueduct. Reaching a population close to a million, unfortunately the rising population ran in parallel with a drought in the region. You see, the area was subject to below normal rainfall, two out of every three years, as quoted by Mulholland himself. And as such, rainfall was very boom or bust, leading to the idea of creating a large reservoir to store up rain from the good years to help the city through the bad. Mulholland proposed an ambitious plan to increase the reservoir capacity around the city, near his aqueduct's terminus. The project would involve modifying existing waterworks and constructing seven entirely new dams, the largest of which would be the St Francis. The new dam would store 30,000 acre feet of water, roughly the amount consumed by city residents in 1922. Surveys for the location for the new dam began in 1922, eventually the site was settled upon and initial clearingworks began. Strangely, but understandably, the initial building works went on with little fanfare, but this was because Mulholland had been burnt before. During the aqueduct construction, sabotage cost the project money as disgruntled locals and landowners sought to cause trouble. By July 1st 1924 preliminary clearingworks had been completed and main construction works would begin around six weeks later. But first we need to look at the design of this shiny new to be built dam. The basic design was actually copied from the Mulholland dam built a year before by, you guessed it, Mulholland, designed by Edgar A. Bailey. This would be the second dam constructed of concrete by the Los Angeles Department of Water and Power. Chief Engineer, W. W. Holbert, supervised the transfer of the design from the Mulholland location to the St Francis location. The main changes were adjustments to fit the new setting or the St Francis area. As such, Bill Mulholland didn't manage the project on the micro level like he had on other designs before. This was exasperated by him being distracted by the concept of a Colorado river aqueduct. Before the designs of both dams, the engineering team studied a number of recent concrete dams such as the Arrow Rock Dam in Idaho and the Elephant Butte Dam in New Mexico. A storage capacity of 32,000 acre feet and an elevation of 1825 feet above sea level was envisioned in 1924 after initial survey work. The Heitler Dam was increased by 10 feet to allow a water capacity of 38,000 acre feet in 1925. The increased size necessitated the construction of a 588 foot long dike along the top of the ridge next to the western abutment. This was not in the original design. As such, the foundations were not widened for the extra height. The design incorporated a curved plan laid out on a radius of 500 feet with a distinctive series of 5 foot high vertical steps on a downstream face of the main dam. Each step was unique in its width and was a simple solution to building a complex curve. The dam didn't have a provision for groutable contraction joints however. A concrete batch plant was built in the canyon of the dam and local aggregate was incorporated with around one barrel of Portland cement per cubic yard of concrete. When the concrete was poured, little thought was given to contractions due to heat given off whilst curing. This combined with the oversight for contraction joints left the dam inflexible and potentially unstable. The reservoir that the dam would hold back began being filled in March 1926. With water diverted from the Owens River Aqueduct and the completed dam was opened in May 1926. During reservoir filling a number of small cracks and leaks were detected but thought to be within expected tolerances. Between March and June the reservoir filled at a rate of about 1.8 feet per day and on May 10th 1927 the reservoir pool reached an elevation of 1832 feet just three feet below the spillway crest. Summer demand kept the water level at that elevation. During the winter months between 1927 and 1928 the reservoir was allowed to fill up to just three inches below the spillway. By around February all of LA's reservoirs were beginning to fill up and on the 7th of March Aqueduct water was no longer diverted to the reservoir. Damkeeper Tony Harnish-Feger alerted the company on the morning of the 12th to dirty water cascading down the slope below the dam's right abutment. The presence of dirty water can give an indication of foundation erosion. Because the reservoir was at maximum fill and new cracks in the concrete were discovered over the previous week Mulholland and Harvey Van Norman arrived to investigate the dirty water and the dam as a whole. Arriving at 11am the two men began to investigate the instability of the structure. The cause of the dirty water was seen to be clear water mixing with loose dirt from a newly constructed road although alarming it was seen as a problem that could be rectified later on. The rest of the structure was inspected and given the seal of approval well how wrong they would be just 12 hours later. Around 8pm employees from one of the nearby powerhouses witnessed a 12 inch wide crack on a nearby road upstream from the dam hinting towards the land around the dam beginning to shift. Ace Hopewell powerhouse number one's carpenter was riding his motorcycle along the road nearby passing the crest of the dam around 11.50pm. He pulled up his bike and sidecar around a mile up from the dam to have a cigarette and to investigate a loud crashing sound. The Southern California Edison company experienced a loss of power at 11.57pm on near 70 kilovolt borough power line that ran near the dam's left abutment extending east woods to Palmdale. The shorting out the power line hints at large scale landslide that enveloped the dam's entire left abutment starting off the disaster. In the closing minutes of the 12th and the opening of the 13th of March 1928 the dam experienced a catastrophic failure. Within minutes the majority of the dam had disappeared leaving only a central section standing like an island. The flow of water was monumentus forming a 140 feet high flood wave washing away large chunk of the wreck dam as 12.4 billion gallons of water surged down. The wave travelling at around 18 miles per hour destroyed powerhouse number two drowning nearly all the workers and their families who lived nearby. The flood water overflowed the Santa Clarita rivers banks flooding present day Valencia and Newhall. By 1am the entire Santa Clarita valley was plunged into darkness. A temporary construction camp set up by Edison company was washed away killing at least 84. The flood damaged the towns of Fillmore, Bardstale and Santa Paula eventually emptying bodies and debris into the Pacific Ocean 54 miles downstream. The flood water was thought to have killed at least 431 people although this number doesn't count migrant workers, casual labourers and illegal immigrants all of whom would have had no record of being in the region. Many dead were never found or identified including dam keeper Tony Harnishfager. Although his wife's body was found near the dam suggesting that a late night inspection was being undertaken potentially due to the landslide sounds heard by Ace Hopewell. So how did such an impressive structure fail so catastrophically? There was and there still is differing theories on the failure. It is thought that the failure started with the left east abutment suffering a landslide. The left fell side was then swept in front of the dam leaving debris as evidence of the likely side of first failure. A committee appointed by the Los Angeles City Council set about working on an official report into the failure. The key failure was placed at defective foundations and the report essentially said the dam was well designed but poorly executed. With an error in judgement about the suitability of the area's geology as a stable foundation for the dam. The investigation though claimed it was the right western abutment that had failed first owing to cracks discovered leading up to disaster but more modern analyses have speculated differently. Two alternate reports by Bailey Willis and Carl E. Gruntsky support the left eastern side failure theory. They also focused into a phenomenon called hydrostatic uplift. This is where water seeps under a dam and causes an upward force on the dam reducing its effective weight. Although known at the time the phenomenon was not properly understood and a St Francis dam didn't take this into account. Meaning that hydrostatic uplift mixed with an unstable land from historic landslips caused the failure at St Francis. The dam was not rebuilt and for a short while became a morbid attraction for locals to come and collect souvenirs as the single standing part remaining known as the tombstone. The site would be cleared and the tombstone demolished in mid-1929 to detract the strange tourism to the area. Because the Mulholland dam was essentially identical, 330,000 cubic yards was used to reinforce it from the risk of hydrostatic uplift. The Hollywood reservoir that Mulholland holds up was not allowed to exceed 4,000 acre feet of water. Mulholland's career also ended on the night of the 12th and the 13th of March 1928. During the inquest he claimed four responsibility and retired in November the same year. No criminal charges were brought against the designers with the inquest finding no evidence of criminal act or intent. Mulholland would die in 1935 at the age of 79. Thanks for watching, I hope you enjoyed the video. If you'd like to help the channel grow you can by liking, commenting and subscribing. Check out my Twitter for all sorts of photos and odds and sods. As well as hints on future videos. I've got Patreon and YouTube memberships as well so if you fancy check them out and all that's left to say is thank you for watching. Reconnaissance was and still is the backbone of a country's ability to collect information on other nations. One piece of the reconnaissance pie is the use of satellites orbiting Earth, taking photos to monitor armies, navies and even nuclear tests. A malfunction in one such satellite would leave a vast portion of Northern Canada irradiated in January 1978. Today we're looking at the Cosmos 954 and its crash and subsequent radioactivity release. I'm going to rate it here 5 on my disaster scale, not great but also not terrible. The Soviet RawSat program shows that not just the USA was looking at the feasibility of placing a nuclear reactor in space. The program consisted of 33 reconnaissance satellites, which were used to monitor NATO vessel movements using radar low orbit altitude. Because of these requirements, a problem was discovered and that was power consumption. You see, the radar needed power and consistent power, something that solar panels alone couldn't achieve. Not only would shadows of the Earth interrupt operation, but the size of the solar panels would affect orbit. Instead, it was decided to use nuclear power. The USSR wasn't the first to explore nuclear power in space, as the US and NASA got their first with the snapshot program, although later RTGs were picked over the fully fledged reactors for future missions. For the RawSat program, a reactor was designed and placed into operation and this would be called the BES-5 and was a Uranium-235 fast-fishing reactor. The reason for a fast reactor was simply no need for a bulky and heavy moderator. This helped bring the weight down of the entire reactor and radiation shielding to just 385 kilograms and this included 31 to 44 kilograms of enriched uranium. The reactor had six control rods and had beryllium reflectors to reflect neutrons back into the core. The Uranium-235 was more than 90% enriched and generated three kilowatts of electrical power from a liquid sodium-potassium thermonic conversion of 100 kilowatts of thermal output. After its operation, use of the satellite was designed to shoot the reactor to disposal high Earth orbit to prevent it coming back to Earth, although obviously at least once that didn't happen. It is known that at least five satellites experience failures with at least one other incident involving radiation release. This brings us to Cosmos 954 and starts the mission on September 8th 1977. The satellite sat atop a Cyclon-2 rocket being launched at 1355 from the Baikonur Cosmodrome. The satellite orbited Earth around every 19 minutes, but this was changed by December when it began to be erratic deviating from its original orbit. To be fair to the Soviets, after it was decided that the satellite was uncontrollable, officials contacted their US counterparts informing them of the situation, including that the now stricken craft couldn't eject its deadly reactor. The satellite, including the reactor, weighed around 4,000 kilograms, all of which were destined to crash somewhere on the planet. Although it was known that the satellite was uncontrollable, it would take several months for it to re-enter the Earth's atmosphere due to the stable orbit it was following. Initial predictions thought that re-entry would happen near to the middle part of 1978, although these predictions would be proven wrong by January. On the 24th January, the satellite entered Earth's atmosphere while above North-East in Canada. Initially, the Soviets claimed that the satellite must have been burnt up in orbit, but this would ultimately be proved wrong. It was discovered that debris from the satellite had been scattered along a 600km area between Great Slave and Baker Lakes in Canada's northwestern territories. This happened during a 3 minute burn up and was observed from telescopic and visual tracking. Searching for the satellite used a joint recovery team of Canadian and US personnel. Some of the radiation detection equipment and aircraft were supplied by the Department of Energy sent from Nevada. All US units were placed under control, also from the Department of Energy. Immediately after the remains of the satellite had been deposited on the ground, US and Canadian teams scrambled to begin search and recovery operations on the 24th January. The search area was divided into 8 sections initially, but this would be extended to 14 sections after area 5 to 8 showed no debris traces. First on the scene was a 22 man Canadian Radiation Monitoring team. The operation was named Morning Light and it was given this rather cool, albeit homemade, looking logo. A rapid recovery was needed as the radioactive content of the satellite posed a serious hazard to life and the environment. The recovery area posed risks in its own right, mostly in Tundra with very little in the way of landmarks, as all, including rivers, was covered under thick snow. Two C414s arrived from the US with radiation equipment and personnel. The equipment was attached to Canadian aircraft with the first being dispatched from Yellowknife on an initial straight line search of over 500 miles. By 4am, four aircraft equipped with radiation detection equipment had been dispatched. Initially, search areas focused on population centres and main traffic areas. By late January 26, teams had deployed at Baker Lake and Yellowknife in preparation for the aircraft to indicate where to search. Computer predictions augmented the air search by calculating the satellite's reentry route. At around 10pm, a radiation hotspot hinting of a piece of the satellite was discovered by one of the planes just near the Great Slaves Lake and by the 28th, locals in the areas were notified of the potential hazard in the area. Signs were erected in both English and several Indigenous languages. Initially, two men from a team of six explorers on a 15-month dog sled expedition across the Northern Territories discovered a strange object in the Warden Grove Wilderness. When the two returned back to camp, they informed their colleagues. Earlier on in the day, the expedition had received a radio transmission about the crash satellite. The team contacted authorities and a recovery team was dispatched. The piece would be later known as the Antler and had a radiation level of 15 ronkin per hour. By January 31st, several pieces of radioactive debris had been located and isolated by ground crews deployed by helicopter. Once on the scene, the search teams made use of handheld radiation detection equipment. Some of the waste was sent to Yellowknife for initial analysis and others were sent to Edmonton. The search effort spanned over two phases between the 24th of January and 20th of April 1978 and the 21st of April to the 15th of October 1978. As time went on, US personnel were phased out of recovery teams. Here are some of the pieces that were found. A metal drum known as the Stovepipe found in sector 1 was a sizeable piece, although it wasn't radioactive. Four steel plate fragments found in sectors 1, 11 and 12 gave off up to 15 ronkins per hour upon discovery. Over 40 beryllian pieces giving off between 600 millironkins an hour to 100 ronkins per hour on contact in sectors 10, 11 and 2. There are also several other smaller chunks with the highest giving off 10 to 30 ronkins per hour on contact found in sector 10. Although one piece was the hottest fragment discovered, gave off gamma radiation of 500 ronkins per hour near contact. This amount of radioactivity is more than enough to kill a human if too much time is spent near it. Not only this, but around 4,000 other smaller particles and debris were found during the recovery work. Non and lower radioactive debris was wrapped in plastic for extraction and higher emitting items were transported offsite in a special shielded container. It was estimated that the total activity over the entire dispersion area would have been around 2,500 curries. This presented around 20% of the calculated total inventory of the satellite. It's really impressive how swift the recovery of the worst of the debris was with collaboration between two countries. Obviously the US assistant had an ulterior motive in the sense of being able to gain intel on the satellite. So with all the expensive recovery operations completed by 1978, who was going to pay for it? You see, if you launch something into space, you are financially responsible for any damage it might cause when it comes back to earth. This was called the 1972 Space Liability Convention, so under the terms the USSR was on the hook for a few dollars. Around 6 million Canadian dollars for expenses was built to the USSR, but they only paid up around 3 million Canadian dollars. The accident didn't stop the raw start program and the USSR continued to launch the satellite types for another 10 years, finally concluding in 1988. A few months after Chernobyl, the Rhine would run blood red as 400 kilometers of the river became contaminated, killing all wildlife within. In November 1986, a fire at the Sandoz Agrochemical Storehouse in the Spreyserhala Industrial Complex, Basel Landschaft, Switzerland would show the risks of poor storage of chemicals in a building not originally designed for this purpose. The incident would also show the side effects of such a fire, as the water used to fight it would mix with the chemical stored and run off into the Rhine and contaminate the nearby soil. I'm going to rate this incident here number 6 on the Painting in Plainly Difficult Disaster Scale. Warehouse number 954 in 1986 was used for chemical storage in Sreyserhala Industrial Complex, measuring 90 by 50 meters. It was originally built as a machinery storage area. Because of this, the building lacked proper smoke detection and sprinkler systems, essential safety systems for chemical storage. The building contained around 1246 tons of phosphoric acid insecticides. Rodicides, herbicides, fungicides, Prussian Blue, emulsifiers, stabilizers, solvents, dodecylbenzene and aminosulfuric acid monophenamine. Now, the cause of the fire has been disputed with even the East German Starzy being accused. But it is thought that the ignition point was Prussian Blue during packaging for storage on the evening of 31st October 1986. The process at the time involved wrapping the pigment in a plastic sheet, shrink wrapped using a blowtorch. During the wrapping, the workmen didn't notice that some of the material was caught by the open flame of the blowtorch. The slow burning material was flameless and smokeless, progressing unnoticed until just after 12 midnight on the 1st of November and emergency services were called. 160 firefighters attended the scene and ferociously fought the flames. The option of letting the warehouse burn down was not allowed due to phosphatine being stored in a nearby warehouse. Because of this, the fire had to be put out as quick as possible to prevent the highly potent poisonous gas from escaping nearby. As such, large amounts of water was used for the firefighting efforts, which would be successfully competed at 3.40am. However, by this time, warehouse 954 had collapsed. Nearby Basil was awoken by an emergency alert as a foul-smelling gas cloud from the blaze was spread across the area. Locals were told not to leave their homes and to close all windows and doors, although this alert was lifted around 7am when the smoke was thought to be non-fatal. It wouldn't be the air so much, as the water that would be heavily polluted, and it would be the very water used to douse the flames that would cause the disaster. The highly toxic mercury compounds were present as fungicides in sea dressings in the warehouse, and were marked with fluorescent red dye Rodamine B. The toxic compounds mixed with the water and flooded the area, making its way into the drains. The Schreiser-Hully Industrial Site had seals that could be closed in the event of an oil spill to prevent effluent from making its way to the Rhine. This is a very useful safety system, although on that fateful night they were not operated. Between 10,000 and 15,000 cubic meters of contaminated fluid flowed into the Rhine, around 30 tons of pesticides, insecticides and around 200 kilograms of mercury were released. Initially the contamination was announced as just non-toxic dye, but this would be proven wrong. On the 3rd of November sandals emitted to the amount of toxic discharge into the Rhine. Just two days later thousands of eels were reported to have died. The pollution by now has spread to around 400 kilometers of the Rhine's water course, and water taken for drinking was cut off necessitating bottled water to be handed out. The pollution waves spread disulfulton and firemeaton. As a side note, estimated lethal dose in humans of disulfulton is less than 5 milligrams per kilogram. Not only the pollution had affected the eel population, but also grayling, brown trout, pike and pike perch had experienced significant damage. Businesses along the damaged waterway shut down. On the 18th clean up works to clear the toxic sludge began, soil was cleaned with special vacuum cleaners in order to prevent it from being washed away with the next flood. Eventually the remains of the contaminants were washed away, and surprisingly the local animal population had already started to replenish itself within three months. The mediation of the fire site where the warehouse once stood and the contaminated soil took about six years were around 2700 tons of semi-combustive material needing to be disposed of. Around 9 tons of pesticides and 130 kilograms of organic mercury had infiltrated the soil surrounding the warehouse. Pollution was detected at depths of up to 11 meters below ground level. Contaminants were removed and sandals installed a shed with a special off gas system for storage. The disaster eroded away public confidence in the self-regulation of the chemical industry in Switzerland. As a direct result from the fire the Swiss government set up a major accident ordinance and chemical safety inspectors. One example of the new regulations was for storage sites to install a basin to collect firefighting water. Some other rules included substances which may react with one another in a dangerous manner, for example large amounts of burnable materials must be stored separately. Based on a risk register around 200 operations with a chemical hazard potential were identified in Switzerland and subjected to the new regulations. The disaster eventually ended up with a net benefit for the local ecosystem as it forced operators and the Swiss government to actively monitor the Rhine. If the proactive measures enacted post-event ever failed a Rhine international warning and a land system were set up with the idea of being able to react almost instantly. Even though no human deaths were linked to the spill the risk to life can't be understated as environmental risks shown at Sandos is only one fire away. Thanks for watching I hope you enjoyed the video. This video is a plainly difficult production. All videos on the channel are Creative Commons attributes share a like licensed. Plainly difficult videos are produced by me John in a sunny south-eastern corner of London UK. Help the channel grow by liking commenting and subscribing. Check out my Twitter for all sorts of photos and odds and sods as well as hints on future videos. I've got Patreon and YouTube membership as well if you fancy supporting the channel financially and all that's left to say is thank you for watching. Architects and engineers strive for striking and innovative design. Minor adjustments in a design are common over the life of a construction project. Although each amendment should be stress tested in order to keep the overall design parameters but sometimes this is overlooked. A hotel in Kansas City would highlight the culture of building maintenance in the 1970s that favoured looks and ease of construction above all else. A disaster would only be one of several structural failures of the era with the 1976 Tent and Dam collapse, 1978 Hartford Civic Centre roof collapse and the 1979 Kemper Arena roof collapse just to name a few. Almost to the day after its completion a hotel in Kansas City, Missouri experienced a structural failure causing the deaths of 114 people. It still remains the deadliest non-deliberate structural failure in American history. Today's disaster shows how something you assume to be safe can be the source of a catastrophic failure resulting in the loss of life. And as such I'm going to rate it here eight on the plainly difficult disaster scale. The suspended walkways are often seen in hotels, shopping centres and museums. Several of these would be a defining feature of the Hyatt Regency's lobby. The Hyatt Regency is part of the Crown Centre complex built by Hallmark Cards adjacent to where most of Kansas City's tallest buildings are located. Construction began in May 1978 and the hotel complex consisted of a 40 story tower, a function building and a connecting atrium area. The total rooms was 733 and on top of the main building sat a rotating restaurant. The hotel also had a 17,487 square foot ballroom and a dedicated exhibition hall. The atrium area was multi-floored and employed free suspended walkways to connect the tower to the function building on the second, third and fourth floors. The third floor walkway was independently suspended from the atrium roof trusses whereas the fourth floor walkway was suspended from the roof framing. The second floor walkway was suspended from the fourth. The atrium measured 117 feet north south by 145 feet east west with a ceiling height of around 50 feet and the walkways ran in a north south direction. The third floor walkway was the widest as it ran to the ballroom area and was intended for large quantities of people. Each walkway was constructed from four pieces made of a steel framed box girders welded together and suspended by one and a quarter inch diameter rods at the end of each piece. Now the original design intended that the rod would be continuous through the fourth floor walkway to the second floor walkway. Under this arrangement each box beam was separately transfer its load directly into the hanger rods and onto the atrium roof. This setup necessitated threads along the whole length of the rod. The fabricator worried that the threads would get damaged during construction and instead suggested an amendment to the design. Instead of continuous rods two separate rods would be used, one running from the roof to the fourth floor walkway with the next set of rods next to it down to the second floor walkway. This had an unwanted side effect and that was the transference of force leading to the fourth floor having to hold up both itself and the second floor. The weight on the roof would still be the same but a nut at the end of the first rod would have to support two levels instead of the one original in the design. The fault was not picked up by the designers a concrete slab was placed on top of the metal frame and formed the walkway. Tempered glass plates held in extruded aluminium gaps and the base of the walkway formed the handrails. The walkways were approximately 120 feet long and weighed approximately 64,000 pounds. Construction completed in 1980 and on the 1st of July that same year the hotel opened to paying customers. This leads us onto the 17th of July 1981. A little over a year after its opening the hotel was hosting a tea dance to between 1200 to 2000 people in the atrium. The event started at 3pm, by 4.30pm most of the seating in the atrium area was occupied and many started to spread throughout the various levels. The busy atrium was brimming with people and because of this many had made their way up to the walkways for a better view of the evening. By 7pm the evening was in full swing and the band returned from a break to begin to play. Around the same time spectated on the 4th floor walkway experienced a strange and unnerving metal scraping sound. At 7.05pm the 4th floor gave way falling onto the crowded 2nd floor. The impact pushed both floors onto the atrium 1st floor below. Many bodies were buried beneath the steel, glass and concrete with many still alive. At 7.08pm the emergency call was sent out to the Kansas City Fire Department. Within minutes Fire Department 1st responders arrived on the scene and requested additional help and equipment to launch a rescue effort. Nearly 20 minutes post collapse a forklift was requested before the end of the first hour more than 100 firefighters and emergency workers were involved in the rescue operation. The total rescue operation would last 14 hours well into the afternoon of the 18th with the recovered dead bodies stored in a makeshift morgue in the exhibition hall. Any available space away from the atrium was used for triage of the wounded. Walking wounded made their way to A&E whilst more seriously injured were treated on site. One such person had their leg amputated by a doctor with the use of a chainsaw. The hotel's sprinkler system was damaged during the collapse and a real risk of flooding was feared. In the wake of the disaster blood centers received hundreds of donations and anyone who could help did with the rescue efforts. With over 200 injured and a total of 114 dead how could the collapse have happened in such a modern building. With a shocking disaster in a new building investigators were faced with a failed structure and the question how. The NSB on a national bureau of standards began their investigation on the 28th of July after a court order covering protective custody of the debris was given to the investigators. Initial measurements, inspections and photographs were taken of the debris and remains at the 4th and 2nd walkways. They found something strange on the 4th floor box sections. The seam weld was strangely bent in a line near where the rods met the walkway, the same part that had been redesigned by the fabricators of the rods. What was also odd was that a number of the washers used at the nut of the rods of the 4th floor were either missing or severely deformed. The theory that was positive was that the stress on the cross beams of the 4th floor had split the welds on the beams seam allowing the floor to slip on top of the 2nd. To prove the theory, the MBS conducted a number of stress tests on identically fabricated segments. The MBS found during its investigation that the constructed walkways were considerably less capable of holding up the design loads specified by the Kansas City Building Code. They also concluded that the rods of the 4th floor walkway had failed causing the total collapse, most notably at the box beam rod connections, where the design had been changed by the fabricator. It was predicted that the original design of a continuous rod was 90 kilonewtons, whereas the actual installation of the interrupted two rod arrangement was 181 kilonewtons, doubled the designer's spec. It was also found out that the continuous rod arrangement would have handled the loads on the walkway on the 17th of July. Although the disaster point was the interrupted rod arrangement, the core failure was in the communication between the fabricator and the designer. The designers had assumed that the drawings made by the fabricator were the final version and checked out. However, if anyone had actually recalculated the loadings then it would never have got off the drawing board. The event became a cautionary tale for future construction projects and the hotel was reconstructed at a cost of around $5 million. Lawsuits totaling $3 billion were sought, with only around $140 million being paid out over the following years. The design firm, Jack G. Gillam, and associates in charge of the hotel's construction was found not criminally responsible, although this would be little consolation, as the company lost its engineering licenses in the states of Missouri, Kansas and Texas. Jack G. Gillam, haunted by the guilt of the event, would take lectures at universities showing the repercussions of his responsibility and the failings in construction of the hotel, hoping that others would learn from his unfortunate oversight. History has a habit of repeating itself when you don't learn from your mistakes. For a second time, the plutonium facility at Rocky Flats would experience a devastating fire. The event would be another chapter in the saga of pollution at the site. The Rocky Flats plant is up there as one of the worst nuclear industry sites for long-term contamination. The facility would experience not one, but two plutonium fires. Now, before I start, I strongly recommend that you watch my video about the 1957 Rocky Flats fire, as it gives a bit more background to the site, and was the worst of the two fires in regards to contamination release. Although it less a disaster, today's subject, the 1969 fire, was the catalyst for the wider public being aware of the site's shortcomings with radioactive containment. As such, I'm going to rate the Rocky Flats plant as a whole, as seven on the painted, plainly difficult disaster scale. The Rocky Flats nuclear bomb factory was located 16 miles northwest of Central Denver. Our story begins in 1957, around the same time as the remediation works to clean up the first fire were undertaken. A new trigger design was beginning to be employed in US nuclear weapons. The new triggers had different shapes of plutonium with closer tolerances, necessitating more rolling, forming and machining than early years of weapons production at the damaged building 77. With the main fabrication building running at reduced capacity, a new complex was decided to be constructed, completed in 1958. The complex was two buildings, 776 and 777, one for manufacturing and the other for inspection. The new building was able to cope with the more intricate manufacturing process for plutonium triggers. After a couple of years of operation, the dividing wall between the two buildings was removed for ease of production. The building was a two-storey structure with a partial basement. The main floor had 135,000 square feet, the second floor contained 88,000 square feet and the basement boasted 600 square feet. Similar to the process used in building 77, the plutonium triggers had to be founded and milled to the correct shape, all of which was done within shielded glove boxes with plexiglass windows. Releases of radiation wasn't just confined to the two rocky flat fires. As between 1964 and 1967, toxic cutting fluid contaminated with particulates of plutonium and uranium were stored in 55 gallon drums on pad 903. Over the years, the drums had corroded on their underside, leaking the contaminated effluent into the soil around the storage area. With some of the waste mixed with dust, between 1.4 and 15ci or 19 to 208 grams of plutonium dust was released contaminating offsite areas to the south and east, necessitating the pad to be paved over with asphalt. Leading up to 1969, over 10 modifications to the complex were undertaken as production grew. Four principal glove box systems existed at building 776, 777. These included North Foundry Line, the South Foundry Line, the Centre Line and the North-South-East Machining Line. All production operations were carried out in glove boxes that were interconnected. This leads us on to the 11th of May 1969, and a small smouldering fire in one of building 776 or 777's glove boxes that were turned into one of the most costly industrial accidents up until that point in US history. At around 2pm, a smouldering began in an open plastic can containing plutonium. As we saw in 1957, the material slowly burns, much like charcoal and again the cause of the spontaneous ignition is not completely known. Eventually the smouldering ignited the plastic, causing a much bigger fire as other materials set alight. The fire was spread about by the glove box ventilation systems. There were very few fire breaks in the line, causing damage to a large proportion of the building. The filters employed in building 776 and 777 were different from the ones in the 1957 and were less flammable, and had 6 banks of high efficiency particulate air filters or HEPAs. This time around the filters worked more efficiently, capturing a large amount of contaminants. By 6pm, the fire was largely contained and fully extinguished by 8. During the fire, 4 filters were severely damaged, leading to a release of material out of the building vent stack. It was estimated that between 0.14 and 0.9g or 10 and 60mci of plutonium 239-240 had escaped into the atmosphere during the fire. The most contaminated area was behind the vent stack on the building's roof, with plutonium all over the structure, and some was tracked in and out of the building by firefighters during the fire. Some plutonium was carried off site by winds, although it is not known by the exact amount. Again, like in 1957, the most exposed were people outside exercising at the time of the release. This is because plutonium predominantly emits alpha particles, which are only damaging to the human body if ingested, for example through breathing. The fire drew the attention of independent radiochemists at the National Centre for Atmospheric Research. Some of the soil on site were taken, and unsurprisingly, plutonium traces were found to be 400 times above the average levels. Officials at the plant were questioned, strangely denied the contamination was from the fire, and instead emitted to the 1957 fire and the release at area 903. And thus the 1957 fire and contamination were now known by the public. After the fire, a two-year path for remediation was laid out, and production was moved to another building, and waste disposal operations began. Cleanup activities were completed on October 18, 1971, and by 1972, all manufacturing was transferred to building 707, with 776 and 777 converted to a waste disposal area. No serious injuries were reported from the fire, apart from one firefighter who inhaled a sizeable amount of plutonium and 32 other employees, all of whom were treated for contamination. All were reported to have made a full recovery, although the effects would have been long-term illnesses such as cancer long after the incident. So take that with a pinch of salt. The damage to building 776, 777 would cost upwards of $26 million to dispose and repair. The disaster had a positive change, however, in the way that Rocky Flats operated. The event pushed forward safety system improvements, including the installation of water sprinklers, firewalls to control the spread of fire, and the use of inert gas for plutonium operations to prevent spontaneous ignition. It's just a shame that all that wasn't brought in after the 1957 fire. Thanks for watching, I hope you enjoyed the video. This video is a plainly difficult production. All videos on the channel are Creative Commons Attribution Share alike licensed. Plainly difficult videos are produced by me, John, in a sunny south-eastern corner of London, UK. Help the channel grow by liking, commenting and subscribing. Check out my Twitter for all sorts of photos and odds and sods, as well as hints and future videos. I've got Patreon and YouTube membership, if you fancy supporting the channel financially. And all that's left to say is thank you for watching. Barges towed by tugs are a common sight on the waterways of the world. So much so, they are often overlooked in the amount of damage that they can cause. An important thoroughfare across the Arkansas River would collapse from a bridge strike by two barges pushed by a tug. The disaster showed the responsibilities of such users of rivers and would result in the loss of 14 lives, 11 injured and a 580 foot section of bridge plunged into the river below. Imagine driving across a bridge only to have it collapse below you. Definitely the field of nightmares, but likely something that you will never experience. However, in a main morning in Webber Falls, Oklahoma, United States, this very scenario would play out, putting a spotlight on the risks of waterway transport. Sadly, the event would be due to an unknown health condition of the boat captain. But regardless of the cause, it shows how vulnerable a bridge really can be. Scarily the collapse wasn't in the early part of the last century, but instead within living memory just over 18 years ago. Today I'm going to rate this disaster here 6 on the Patented Plain Difficult Disaster Scale. This is due to it being deadly, but not having too much in regards to environmental implications or long-term health effects, apart from the obvious mental trauma of the survivors of the disaster. Our story starts in 1967 with a newly constructed I-40 bridge spanning the Arkansas River near Webber Falls. The I-40 bridge is a twin girder continuous span bridge consisting of 13 concrete sections that were 7.5 inches thick. Supported by steel girders and a steel superstructure that was in itself supported by 12 reinforced concrete piers and two bridge abutments. During the construction design of the bridge considerations were not given for lateral loads caused by collisions and this was standard for the era. On the west piers 1-4 supported the bridge and to the east piers 5-12. Each pier consisted of three main sections with section 1 attached to the bridge footing with section 3 supporting the bridge span. Bridge strikes or collisions as they are known were obviously a known risk by the early 2000s as such impact mitigation was provided in the form of reflectors and lights. These consisted of red lights and red reflectors affixed to the steel girders marking the location of the main span piers for north and south shipping traffic. With green lights and green reflectors marking the center of the main span the main span was between pier 4 and 5. A green boy was located 0.35 miles from the bridge marking the upbound left side of the channel. In case all that didn't help the bridge had pier protection sails on the northern approach for pier 4 and 5 only. Extra protection consisted of 10 inch by 18 inch by 89 feet long treated wood planks attached to the inside face of piers 4 and 5. These were installed in the 80s due to a number of unreported bridge strikes in the late 1970s resulting in superficial cracks in the concrete structures. The cracks were repaired with grout to prevent progression of the damage. The Robert Wylove was a diesel driven inland river tugboat operated by the Magnolia Marine Transport Company. The vessel was built in 1955 and the twin screw tug was originally named Caroline under its first owner. She was sold in 1992 to MMT where she undertook upgrade works to her engines. Robert Wylove was 104 feet long with a width of 30 feet. She had recently had her dry dock inspection in March 2002 and was given a clean bit of health with no issues with her control equipment. In May 2002 she was pushing two barges also owned by MMT named MM60 and MM62 both built in 1999. Both were identical in size at 297.5 feet long with a width of 54 feet. They displaced 402.6 and 427.4 long tons respectively. The section of the river that the I-40 spanned was controlled by LOX as it was part of the MacLennan Care Arkansas River Navigation System which itself formed part of the United States inland waterway system. Due to this the river had little in the form of current, meaning water traffic could make easier progress throughout the network. At 3.40 in the morning of the 19th of May 2002 the tow boat Robert Wylove departed on route to Katuna. She was pushing two empty barges and on the 23rd of May the vessel and her barges entered the M Khan system. At 18.40 on the 25th of May the alternate captain was relieved by the regular captain and took over the watch being relieved himself by the pilot at 22.45. The regular captain was 60 years old and had been in charge of the Robert Wylove since February 2001. He had over 40 years of experience through his marine career. The pilot was then relieved by the captain at 5.30 am on the 26th. You see the shifts on board most vessels like this are 6 hours long, meaning 6 on 6 off. In the interest of good journalism I tried out this type of shift pattern for one of my days off and it's pretty brutal but maybe you just get used to it. At around 7 am one of the crew members went to the wheelhouse to clean up. After completing his duties he chatted to the captain for around half an hour. The usual approach to the I-40 bridge was along the centre of the river guarded by boys. GPS data collected post event showed that the vessel followed the usual path until around here, where she went off course. Would the vessel travelling at 6.7 miles per hour? The captain later told investigators that he remembered passing the boy to port and using a few degrees of left rudder to align his toe through the navigation span at the bridge. At this point he blacked out and the Robert Wylove was just 4 minutes away from impact. At around 7.45 am the toe struck pier 3, about 201 feet west of the navigational channel at around a 56 degree angle. Pier 3 was not designed to be crash resistant. This was due to the main navigation route being between 4 and 5. And because of this it collapsed taking the bridge span with it. The collapse damaged pier 2, in total over 500 feet of roadway disappeared into the river below. Some of the debris landed on the barges with the crew on board witnessing several vehicles drive off into the void. Nearby participants of a fishing tournament witnessed a mayhem and phoned 911 with one of the party firing a warning flare into the sky. By now the captain had regained consciousness, witnessing the incident in front of him he sounded warning blasts on the boat whistle. In total 8 passenger vehicles and 3 tractor semi-trailer trucks had fallen into the river or onto the collapsed portions of the bridge span. 3 people who had escaped their vehicles after falling into the river had managed to get to shore with the help of the recreational boats in the area. At 7.48 am the first of the emergency responders, members of the local police arrived on the scene. 6 ambulance responded with the first arriving at 7.56. 11 local fire departments, 10 EMS departments, 8 emergency management agencies, 7 state agencies and 7 federal agencies would all assist. A total of 58 local, state and federal agencies responded to the accident. The Robert Y Love did not sustain any damage due to it being at the back of the tow. However both barges were severely damaged, costing over $275,000 to repair. But obviously that would be the smaller amount in terms of damage cost. The I-40 bridge, damage and associated costs came to just over $30 million. The I-40 was closed for 65 days whilst repairs and reconstruction work was undertaken. The bridge was struck in an area not reinforced due to the intended traffic flow being between the 4th and 5th piers, which was the structural failure point of the collapse. But what was the actual cause? The person in control of the tug had navigated the waters many times over their career and was familiar with the area. He obviously was experienced with the amount of years working in that industry, which leads on to the question how did the tow make contact with the bridge? The captain of the tug reported that he had experienced a blackout on approach to the bridge. After drug and alcohol tests showed up negative results, investigators looked for any possible medical explanation. Medical experts suspected a condition called syncope, which can cause a lack of blood flow to the brain. Usually in an incident like this the person would fall to the ground, which would then allow blood to flow back to the brain, allowing consciousness to recover quickly. In the case of the captain and the wheelhouse's limited space, he didn't fully reach the floor. Instead he was supported in a crouching position, leading to an extended period of unconsciousness. In a week leading up to disaster, he had felt a number of periods of dizziness, but had attributed it to fatigue. It was found that in the 72 hours leading up to the event, the captain had a sleep debt of around 12 hours. Post accident, the captain was subjected to several tests to investigate this theory, with abnormal heart rhythm and clogged arteries discovered. Both can be causes of syncope. Traffic resumed on the 29th July 2002 in a record turnaround time. The NTSB recommended a bridge warning system for road users and a wheelhouse alert system for marine vehicles. Thanks for watching, I hope you enjoyed the video. Would you like me to cover more bridge disasters like this? Let me know in the comments. This is a plainly difficult production. All videos on the channel are Creative Commons Attribution Share alike licensed. Plain difficult videos are produced by me, John, in a sunny southeastern corner of London UK. Help the channel grow by liking, commenting and subscribing, and check out my Twitter for all sorts of photos and odds and sods, as well as hints on future videos. I've got Patreon and YouTube membership as well, so if you want to support the channel financially, you can do through there. And all that's left to say is thank you for watching. Today's subject shows the pitfalls of when little fault is given to safety design and operational procedures of an electronic accelerator. The National Centre for Scientific Research is an organisation that runs several facilities in Vietnam, which use ionising radiation for research. But we'll be focusing on just one of these facilities. I'm going to rate this subject here free on the patented plain difficult disaster scale. This is due to the incident only really affecting one individual, but it's going to have a six on the historical legacy scale due to it being a vital lesson for operators of these types of machines. The Hanoi Institute of Nuclear Physics will be the setting for today's subject, based in Vietnam. The facility worked on photon and neutron induced nuclear reactions, material analysis using photon and neutron activation, x-ray fluorescence spectrometry, and geology, medicine, agriculture, industry and environmental applications of nuclear techniques. The HINP operated two electron accelerators, gaining its first in 1974. The second, a microtron MT-17, was attained in 1982. The first electron accelerator by the early 90s was no longer in operation due to parts shortages. The MT-17 was originally built in 1973 at the Joint Institute for Nuclear Research at Dubna, USSR. It produces neutrons and x-rays from electrons accelerated up to 15 MeV. In 1980 the JINR stopped using the unit and in 1982 shipment to Hanoi was arranged. The JINR and the HINP had a good working relationship with an exchange of training and equipment. The area that would house the MT-17 was designed to copy that of the Dubna facility, although the only manual shipped with the machine were supplied in Russian, causing a bit of a problem setting up. The accelerator room walls had a thickness of 1.8 meters, and leading into the room was a hallway called the maze and this had wall thicknesses of 1.4 meters. No audit of the completed installation safety systems or dose rate surveys outside the room to assess the efficiency of the shielding was conducted. Practice for the operator's radiation monitoring skills was limited to experience gained from Dubna. Due to the reduced funds of the Institute, no active radiation monitoring was undertaken. Before we get onto the accident, let's have a brief look at the MT-17 and how it works. The MT-17 electron accelerator could produce x-rays by accelerating an electron beam to 15 MeV into a 2mm thick tungsten plate. The unit can also produce neutrons by bombarding a uranium target with an electron beam. The electron beam is created in a magnetron, guided along a tube to a cathode and accelerated in a circular orbit using magnets and directing them to the appropriate target material. The control console didn't have a key to switch on, but was considered safe at the time due to all the writing being in Russian, which is a questionable safety feature. Samples can be transferred into and out of the accelerator room remotely, if desired, through a hollow plastic tube that leads from the accelerator room to a counting room. When an item is to be irradiated, the tube and inside the accelerator room was placed manually in front of either the tungsten or uranium targets and compressed air was used to deploy or retract the sample. No timing device or dose control cutout was installed at the facility for the machine and instead radiation dose times were counted on a wristwatch. Radiation measurements were taken from a detector positioned halfway down the May's wall with no indication in the accelerator room itself. There was no interlock on the door that led to the accelerator room, meaning anyone could walk in unimpeded during a radiation and word of mouth was used to inform staff of an experiment being in operation. There were however immediately outside the accelerator room door and in the corridor to the control room signs that became illuminated when the beam current was switched on. And bizarrely, radiation monitoring was never undertaken outside of the accelerator rooms, meaning no one knew if the shielding walls were actually effective at all. Apart from short training courses, no in-depth instruction was ever given to safe working practices leading to a non-safety focus work environment. Which leads us on to the 17th November 1992 and one employee at the HINP would experience a sharp end of safety complacency. On the morning of the 17th November 1992, a research group led by the facilities director were doing an experiment on irradiating a gold ore sample. The air compression based sample extraction system was not being used that day due to the sample only needing to be irradiated for around an hour. Initially, the day starts off successfully with the first sample experiment going to plan. A second sample was placed in front of the tungsten target by a three-person team led by the facilities director. The team walked towards the control room out of the maze area along the hallway. The director asked one of his assistants for some soap and turned to walk towards the courtyard area where there was a sink. The assistant had to pass the control room to collect some soap and on her journey she said to the operator that the experiment was ready to start. What she didn't know was that the director questioning his placement of the sample had re-entered the MT-17 room. He repositioned the sample using his hands and was only around three to thirty centimetres from the target. Upon returning the assistant couldn't find the director but did find the MT-17 door open. She shouted out for him but received no reply. Meanwhile the director was in the room using wax blocks to secure the sample and at that moment the magnetron was powered up and a noticeable sound could be heard. The director had not noticed the implications as all the equipment and air conditioners running created a distracting ambient noise. Upon discovering the MT-17 door open the assistant called inside but again no reply as her voice was drowned out by the background noise. She ran to the control room and told the operator to shut down but it was too late and the accelerator had been in operation for at least two minutes with a beam current of six microamperes. The assistant and the control room operator made their way to the MT-17 room to find the door open and upon entering found the director still handling the sample. Calmly the director exited the room and after a few minutes later after realizing what had happened he proceeded to the measurement room to use the germanium crystal gamma spectrometer. A peak of 511 kev was showing up. Not really knowing the implications nothing much else was done apart from another measurement of the director's hands in the gamma spectrometer but no peak appeared. Staff at the facility knew of the accident but little more thought was given to its implications and work seemed to carry on as normal. The director continued on with his day and when returning home felt a strange sensation in his hands. Being a sufferer of arthritis he pegged a new feeling down to that and washed his hands with warm salt water. He carried on his daily routine as usual going to work for around eight days. Ten days post exposure he went through his annual medical check and even then nothing unusual was spotted. As his hand began to swell up the director requested a hospital examination. Over two weeks post exposure he was hospitalized with the quite obvious serious injury he had suffered and only then it was concluded that the damage was due to radiation. Day 24 post exposure the patient had experienced difficulty in moving his fingers due to the swelling. Initially antibiotics and lotion was used but eventually the skin had begun to develop necrosis. It wouldn't be for nearly two months post the event that the official regulatory body in Vietnam, Vinatom, would hear of the accident. A report into the incident was requested which was delivered on the 2nd of February 1993. The National Centre for Burns who were treating the director predicted a dose near 25 grey but in March the same year dose rate measurements estimated that he had received between 20 and 80 grey depending on the actual time the beam was on his hands. The reference a whole body exposure of 5 grey can lead to death within two weeks. After these results Vinatom requested assistance from the IAEA. Interestingly Frog's skin was used to try and heal the hands but 50 days post exposure on the 5th of January 1993 the first skin graft was administered. Day 127 post exposure an IAEA doctor examined the hands of the patient and an estimate of 50 grey of exposure to both hands was suggested and she recommended amputating one of the most affected fingers. The patient was then under the recommendation of the IAEA transferred to a hospital in Paris due to his worsening condition. After admission on day 159 on the 24th of April his left hand showed signs of improvement but his right hand had a severe infection at the amputation site of the finger. On day 226 the 30th of June his forefinger on the right hand was amputated in the hope of saving the thumb but necrosis and pain continued. After months of pain skin grafts and necrosis his whole right hand was amputated at the wrist. After the successful surgery he was discharged to outpatient status and stayed near the hospital in Paris but three months later latent radiation effect began to spread to his left hand. Eventually another two fingers would need to be amputated before his eventual return to Hanoi in July 1994. The aftermath and on the recommendations of the IAEA a magnetic lock was installed to the accelerator room door which would if not closed give a warning to the control room. A previously faulty warning bell in the accelerator room was repaired and this could alert anyone that the beam was about to be in operation. The IAEA also recommended about automatic pre-warning, automatic warning, emergency cut out buttons, door interlock system, search and lock up system, area radiation monitors, warning signs and a closed circuit television system being installed at the facility. As well as all this a proactive approach to safety training had to be implemented. An accident such as this shouldn't have happened but unfortunately lack of knowledge and funds allowed a severe lack in correct safety systems and procedures. The victim although unlucky with the loss of a hand and fingers it could have ended up with a whole body dose leading to slow and drawn out death similar to that of Hisashi Auchi just a few years later. When you think of a metro network images like this might pop into mind. I know for me it brings back memories of the Jubilee line at 6.45 am at Canada Water. If you've been there then you know what I mean. Being so close to your fellow travel compatriots, apart from being a great way to spread coughs, colds and a certain current event virus it is also a valuable target for people with nefarious reasons. Although I've painted a London Underground style picture today we're actually looking at the Tokyo subway and an incident in 1995. The Tokyo Metro is the gold standard for efficient railway operation and is something to really gaze in awe at. The frequency and predictability of the trains would be its Achilles heel in attack however. You see the more efficient a network is at transporting people the more efficient it can be at transporting a biological weapon meaning a higher exposure rate to the public. Now we'll go into more detail in a bit but the weapon of choice Sarin can be very effective on board a very packed subway train and as such I'm going to rate this disaster here 8 on the patented plain default disaster scale. This is due to the potential that the attack could have had for many more deaths if it wasn't for the poorly manufactured Sarin and I'm going to rate it here 6 on my historical legacy scale as lessons have been learned but subway networks around the world are still vulnerable. Before we go on to the attack let's have a look at who was behind it. Now I'm not going to go into too much detail here as we don't normally talk about anything religious on plain difficult however there is a great episode of the Necronomapod on the Umsham Rikio Japanese New Religious Movement and this was who was linked to the attack in 1995. So I'll be referring to the perpetrator of the attack as the group or other nondescriptive terms and I won't be mentioning any of the attackers by name as well. The group started in 1984 in a one bedroom apartment in Tokyo's Shibuya ward starting off as a yoga and meditation class. The movement developed into a new religious organization during the 1980s. It gained official status as a religious organization in 1989 and attracted a large number of graduates from Japan's elite universities which in turn helped boost its popularity. In 1993 the group started manufacturing their own nerve agents after a small laboratory in a Kamikwishiki complex named Satyan 7 was built in November 1992. During this period they had tried to make automatic rifles and anthrax as well as many other different types of weapons for an attack on the Japanese people to try and overthrow the government. By 1995 the group had been responsible for several incidents including assassinations, the ex-attacks and an earlier sarin attack. Fearing an attack on their compound the group decided to carry out a massive attack on the Tokyo population using sarin to try and distract the Japanese authorities. Before we have a look at the event let's find out what sarin is and how it is deadly. Sarin is a colourless and odourless extremely toxic, synthetic, organophosphorous compound. It is classed as a chemical weapon and depending on the dose can kill you between 1 to 10 minutes after exposure. The Asian is thought to be up to 26 times more deadly than cyanide and is toxic to human beings on both ingestion and skin contact. Meaning people assisting victims can also be affected. After exposure the victim would experience the following symptoms. A runny nose, tightness in the chest and constriction of the pupils. Later on difficulty breathing and nausea would follow. As they continue to lose control of bodily functions vomiting, defecation and urination may be experienced by the victim. Sarin is an inhibitor of acycolinesterase which is an organic chemical used in the brain and is released by motor neurons of the nervous system to activate muscles. The agent has been used by many countries since its discovery in 1938 and its first known victim was Ronald Madison in Port and Down. Maybe I should cover that in a future video. Sarin is very unstable and evaporates from liquid to gas quickly but also decays in a relatively short amount of time. Meaning it is very deadly but not for long. The satyan 7 was a very small but very well equipped and stocked manufacturing facility. But this did not ensure safe operation as a site experienced several accidental releases of various agents. This led to many of the workers falling ill to mild sarin exposure. But in the poor conditions the group members managed to make 3kg of sarin which was used in the Matsumoto attack in 1994. As a little side tangent this attack used a converted refrigerator truck to pump a cloud of sarin to its target which is absolutely insane. The attack killed 7 people in the aftermath and an 8-14 years later with over 50 injured. Sorry a bit sidetracked there. With a tip off that the compound would be raided frantically made more sarin for another attack in the hope of creating a distraction to local authorities. Due to the rushing of the production process this time around the quality was only half of that at the Matsumoto attack and instead of a colourless liquid had a brownish hue. Around 30kg of the agent was manufactured and placed into plastic bags ready to be used in one of Japan's worst terrorist attacks. This leads us onto the attack on the Toko subway on the 20th of March 1995. Five attackers and five getaway drivers set out to release the deadly agent into several trains on the Toko subway in the rush hour peak. Each attacker had two bags filled with sarin and an umbrella with a sharpened point to pierce the bags. Three lines were selected, the Chiyoda line, the Marunouchi line and the Hibiya line. The attackers had set direction on where to puncture their bags on trains heading in particular directions. This was to ensure that the attack happened at the same moment on five different trains that were travelling to the centre of Tokyo to create maximum damage. After the bag was punctured the sarin liquid would begin to evaporate and its fumes would permeate the railway carriages affected by the attacks. Not long after the attackers had fled their respective targets the trains passengers started to feel the effects of the agent. The worst train for casualties was Hibiya line A720S, the south west bound 0743. The attacker on this train made the most amount of punctures in his packets of sarin. Not long after the assailant escaped passengers started to feel sick. Noticing the large liquid soaked package on the floor and assuming it was the culprit, one of the passengers aboard the train kicked the packets onto Kodon Macho station's platform. With a puddle still on the floor the train continued on and more passengers were feeling ill. By the time the train reached Tejuki station multiple casualties piled on the platform. Eventually all the five affected trains were taken out of service for investigation and the cause of the passenger injuries. Many of the injured suffered from vision problems with many experienced convulsions, shortness of breath and nausea. Many of the affected stations were strewn with injured as they awaited treatment and transportation to hospital. In over over 600 were transported to hospital with nearly 5000 making their own way for treatment across Tokyo's medical centers. Some of the less affected actually went to work with many only realising their exposure after reading news reports. During the event many of the victims were secondary exposures from people already exposed with the agent amongst their clothes or on their skin. Not knowing the cause of the attack meant that subway workers inadvertently were also affected leading to mass panic and chaos on the platforms. In total three lines were affected necessitating decontamination works. The efficiency of the subway system meant that the affected victims were kept in service longer than they should have leaving more people open to exposure. Medicine for sarin poisoning had to be shipped in from smaller towns where it is used as an antidote for herbicide and insecticide poisoning. The bullet train network was used for the transportation. Just over a month after the attack for compound owned by Um Shinrikyo was raided by the police and JDF in an armed show of force, fearing a violent retaliation from the group. In total all of the perpetrators were caught with the last being arrested in 2012. In all five of the attackers were sentenced to death and were executed by hanging along with other key leaders of the group in 2018. The remaining perpetrators of the attack were all given life sentences and these were mainly the getaway drivers. Only one of the people that actually set off the sarin attack on the subway network in 1995 showed remorse and because of this he was given a life sentence. The attack shows how mass transit networks are vulnerable as their design efficiency in transporting people leads to less strict security controls. I mean imagine going through airport security for traveling on the tube. This video has been a bit of a different subject from normal but I thought it was really interesting. So thank you for my patrons for voting for the subject. Thanks for watching, I hope you enjoyed the video. This is a plainly difficult production. All videos on the channel are Creative Commons attribution share alike licensed. Plainly difficult videos are produced by me, John, in a sunny south-eastern corner of London, UK. Help the channel grow by liking, commenting and subscribing. Check out my Twitter for all sorts of photos and odds and sods as well as hints on future videos. I've got a Teespring store if you fancy wearing some of my T-shirts and I've also got Patreon and YouTube membership if you fancy supporting the channel financially. And all that's left to say is thank you for watching. The Railway's safe operations are taken for granted especially in the UK where very few serious accidents or collisions happen. This is due to over two centuries of safety innovations evolving the industry. The UK has complex signalling systems to ensure that two trains aren't allowed on the St Peter Tracker one time. However this rule has been broken by either operator error or infrastructure failure and most of the time the error doesn't lead to a catastrophic outcome. But a poor wiring installation would cause a free train collision costing 35 lives and over 400 injured. In the modern railway, one thing above all else is paramount and that is safety. This is quite an obvious statement as trains are large metal boxes travelling at speed which are filled with hundreds of people with a collective friction area of the wheels not much larger than a pound coin. The low area of contact between the wheels and track means that they are very efficient which is great for carrying heavy loads at lower energy costs than road vehicles. Today's disaster is not important just because of the human and infrastructure cost but it is the cornerstone to modern day health and safety regulations for safety critical work. This video is about the Clapham Rail Disaster on the 12th of December 1988. Today I'm going to rate the Clapham Rail Disaster here five on my Painted to Plain Difficult Disaster Scale. This is due to the disaster not having a wider environmental impact but it is an eight on my historical legacy scale. Safety critical systems are usually designed to revert to a safe state in the case of any breakdown of operation. This is known as failsafe. An example of this is electromagnets holding control rods out of a reactor core. In the case of loss of power the rod falls with the help of gravity stopping the chain reaction. On the railway this is no different. If a signal fails it reverts to danger or red. This is usually a given but in the closing years of the 1980s a simple wiring fault would bypass the failsafe state. But before we get onto the disaster let's have a very brief look into UK Railway Signalling and I mean a brief look as I could probably make a whole documentary if I was allowed to go into a deep dive. Trains are very efficient as I said earlier which is great for fuel usage but can be the achilles heel of rail vehicles. You see less friction means less ability to stop and I really mean less ability. If you can see another car slam on the brakes in front of you when you're driving you have a pretty good chance of stopping well before you become a human can of spam. This is because you have a lot of friction between your grippy tyres and a nice skin shredding asphalt. Trains don't have this so you can't rely on line of sight to stop two trains becoming one big squashed one and to allow safe stopping signalling is used. In basic signalling principles the track is broken up into multiple sections where only one train is allowed one section at one time. Each block section is protected by a signal behind it. There are also overlaps which are an extra section of track giving an extra area for safety in case of an accidental entering of an occupied block section. The UK on many of its main lines use four aspect signalling this enables trains to be at a safe braking distance from one another and can give the driver advanced information of where the next train ahead is. On lower speed subsidiary lines and on London Underground excluding the automatic ones three and two aspect signalling is used but for today we're not going there. Four aspect signalling can show you, you guessed it, four indications. The first is proceed or green this means that at least three signal block sections ahead of you are clear and you can proceed at line speed. The next signal is preliminary caution or double yellow meaning the next signal is at caution and you should probably be thinking about slowing down in preparation for a stop further down the line. Then there is caution which tells you that the next signal was showing danger or stop so be prepared to stop at the next signal. And finally there is danger stop shown by a red. This is pretty simple as it means stop as there is most likely another train ahead of you or the route you are going to take is not set yet. Right well that was a very brief and quick lesson on UK signalling. If you fancy a more in-depth video check out this charmingly dated BR video on the subject. The next thing to look at is the disaster itself and our story starts off with signal Whiskey Alpha 25 has been abolished and a new four aspect automatic signal Whiskey Foxtrot 138 printed in a weekly notice for drivers. Although signalling changes are not a really regular occurrence it is not unheard of and would largely be taken as it was an important but minor change in the grand scheme of things. Likewise for track workers tasked with fitting the new signal it was a regular occurrence for them presenting little in the way of a challenge for someone in that line of work. The new signal would be the cause of the disaster after installation of other wiring during a period of weekend engineering work. The fault would only show itself on a weekday morning rush hour as Clapham junctions saw short headways between trains. You see during the weekend less trains run meaning it is less likely for them to stack up at signals and traffic would be more free flowing. The location of Whiskey Foxtrot 138 was the penultimate signal before Clapham Junction in a railway cutting heading towards London. The previous station was Erlsfield. The signal was meant to protect trains that were standing just outside Clapham whilst they awaited a free platform. The final signal before entering the station's platforms was controlled by the Clapham Junction A signal box. Where trains movements were controlled and more importantly where the relays and interlockings for the signals in the area were housed but a fatal wiring error meant that the signal would not display a stop aspect after a train had passed it which basically defeated the whole point of it being there. On the early morning of the 12th of December 1988 multiple trains had passed Whiskey Foxtrot 138 with no issues. Due to the frequency of five minutes between trains all drivers were seeing green signals. Until the beginning of the morning rush hour leading up to 8am as more trains were going to London the pinch point of Clapham Junction's time between trains decreased to two minute intervals. This is business as usual for one of the busiest railway stations in the UK. A large number of drivers throughout the morning had noticed strange but not unusual irregularities with the signal sequence. This was due to the signal in box A changing routes into different platforms causing the signal ahead to go back to red and the signals to the rear to react in sequence. In the rule book drivers were required to report a signal being more restrictive but due to this being a regular occurrence many ignored this and carried on as usual. This leads us on to the driver of a bazing stoke to London Waterloo Service Mr. McLimons. The 29th train booked to go along past Whiskey Foxtrot 138. As the train made its way past Earlsfield nothing out of the ordinary was noticed until the driver received an unexpected setback when signal Whiskey Foxtrot 138 had changed from green to red as the train was about to pass it. Not being able to stop in time the driver continued to next signal to report the incident. Driver McLimons left his cab to walk along to the signal telephone to contact the signal to find out the issues as per the rule book. McLimons had assumed that the signal that had changed back on him Whiskey Foxtrot 138 would stay red at his train occupied the section. An assumption that should have been right at a fully working signal. The 30th train, the 6.14 am Paul to Waterloo driven by a Mr. Rolls had been making progress towards London following driver McLimons train with nothing worth noting on the journey. His train approached and then passed Whiskey Foxtrot 138 at green at roughly 50mph. Driver Rolls thought nothing of it until the next thing he saw the rear of driver McLimons train by now disaster was inevitable. Driver Rolls applied the emergency brakes bringing the train's speed down to around 35mph as it impacted the rear of the train in front at 08.10 am. The front of the train had left the tracks and a third train running empty in the opposite direction collided with the Paul train. A fourth train following the Paul train managed to stop short in the rear. At the time of the impact driver McLimons was walking back to his train at which it moved forward several feet. He ran back to the signal telephone to inform the signaler who put all the signals under his control to red to stop all train movements. The impact of the front of the Paul train on the last carriage of the basing stoke train caused the last carriage to be thrown up above a concrete wall on the side of the cutting around 10ft high. It came to a rest lying on the embankment above the wall. The first two coaches of the Paul train had veered to the right where it had been struck by an empty train. The noise from the collision attracted the attention of nearby residents and workers around the north side of onesworth common. Many called 999 requesting emergency services. Waringly British rail contacted the emergency services after the first 999 calls at around 8.15am. This was due to the lengthy process of communication from driver to signal box to station supervisor to network control who finally contacted 999. The public had made their first call at around 8.13am. Pupils and teachers from the nearby manual school who were the first on the scene of the disaster helped the walking wounded. Access for the emergency services was limited. This was due to the majority of UK railways being fenced off from the public to prevent trespassers. The railway boundary has access points but these can sometimes be hard to find and require key access. The first three carriages of the Paul train had been severely damaged. The first carriage had totally collapsed. The second carriage, the buffet car, had been devastated on its left near side and the last car of driving McClimb's basing stoke train was also severely derailed and damaged. All of these factors further hindered the first responders. It was estimated that around 1500 people were aboard the Paul train creating an overwhelming situation. The trains in use at the time were of a very old design first generation British rail electric multiple unit and made use of slam manually opened and closed doors which can be opened at any time. Very different from the power control doors of today. Because of this many had already started to escape the wreck trains. The rescue effort would last the rest of the morning into the afternoon. The last casualty was taking the hospital at 1.04pm and the last body was removed at quarter to 4pm. Repair works in the area would take a lot longer as the damaged trains and infrastructure had to be removed before trains could run safely again and this doesn't include the investigation into how the disaster could happen. With 35 dead, 484 injured the big question looms. How? How can a tried and tested signalling system fail to do the one thing it was designed for and that was protect a train in its respective block? Whiskey Foxtrot 138 was obviously not working as intended which as it was a new installation hints that the engineering works were the root cause of the disaster. The replacement of the signal was part of a much wider program called WARS or the Waterloo Area Re-Signalling Scheme. This came about as by the 1970s and 1980s much of the 1930s wiring responsible for the safe operation of the railways had badly deteriorated. The program was undertaken over multiple weekends to improve the reliability of the signalling system. The wiring of the new signal was prepared and laid out over the week to be installed over the weekend. The signal and its wiring was completed on Sunday the 27th of November. It was common for the technicians who laid out the wiring to install it over the weekend leading to a seven day week and for Whiskey Foxtrot 138 this was no different with the book technician working his 13th consecutive seven day week. During the wiring installation the wires to the relay room in signal box A for the old signal needed to be removed as the new signal was wired to the track circuit block. It was deemed not ideal to fully remove the old wiring and instead it was opted by the technician to leave it in situ albeit disconnected. This is not unheard of as long as precautions such as disconnecting cutting back and taping off the stop the loose wire from coming into contact with any other terminals. The technician decided to keep the old wire still connected on one end and just disconnect and push back to one side the other end with the new wiring holding it out of place. Eventually this loose wire could work itself back to the terminal of the new signals wiring in the relay room causing the signal to not go to danger when the train occupied the block. No independent inspection by the technician's supervisor was undertaken meaning the shoddy work was not picked up upon. The signal would operate as intended until the weekend of the 11th of December where unrelated work was being undertaken in the relay room on the relay next to the new wiring. The work disturbed the uninsulated wire which had made its way back to contacting the relay causing the failure of signal Whiskey Foxtrot 138. The investigation by Lord Hidden found many contributors to the disaster including poor training, supervision, assessments, all of which were compounded by technical staff not properly understanding the ramifications of signalling failures. One of the largest legacies of the report into the disaster was the amount of hours the technician had worked. It would eventually prompt a change in working hours for people undertaking safety critical work to 12 hour maximum shifts, 12 hours minimum between shifts, a maximum of 72 hours per week and a maximum of 13 days in a row. If you've ever worked on the railway then these rules are hammered into you. The accident changed the culture in British rail and although no one was charged with manslaughter BR was charged with the health and safety at work act 1974 and had to fork out a £250,000 fine which doesn't seem like enough even for late 1980s and early 1990s money. This event would be partially responsible for the corporate manslaughter and corporate homicide act of 2007. The lessons learned from the accident would help shape the modern UK railway which would never be forgotten. At the time of recording this script I've just finished working on a Tokyo subway attack video so it's been a few weeks of railway stuff for me. I've really enjoyed working on it but more importantly though, have you enjoyed the rail based subjects and do you think I should cover more? Let me know in the comments below. Thanks for watching, I hope you enjoyed the video. This is a plain difficult production. All videos on the channel are creative commons attribution share alike licensed. Plain difficult videos are produced by me John in a sunny southeastern corner of London UK. Help the channel grow by liking commenting and subscribing. Check out my Twitter for all sorts of photos and odds and sods as well as hints on future videos. I've got Patreon and YouTube membership as well if you fancy supporting the channel financially and all that's left to say is thank you for watching. In 1977 a disaster would show the risks of heavy rainfall on an embankment dam resulting in structural failure. The resulting floodwater would cause nearly $3 million worth of damage and cost 39 lives. What was strange was that the structure was not new. Instead it was in its final arrangement for over 30 years which really shows that nothing is solid forever. Dam disasters are always scary incidents as seemingly unmovable imposing structures give the full sense of security for the vast water it holds back. This is why when a dam does fail it does so spectacularly. The Kelly Barnes Dam had the double surprise of being a pretty well established structure with varying designs being employed on the site ever since 1899 with failure occurring in 1977. Although the final iteration at the site was not as grand as say the Sayano Shyshenska due to it being a relatively simple earthen dam. Today's subject I'm going to rate it here 6 on the Plain Difficult Disaster Scale and here 4 on the Historical Legacy Scale as it is a relatively unknown failure in comparison to say the Yonk Disaster. The city of Tokoa, Georgia is a smallish municipality with a population today of around 8,000 people but the purpose of this subject we're going to start all the way back in time in the late 19th century. Tokoa was destined to have a hydroelectric plant and as such this necessitated a reservoir. In 1899 a rock crib dam was built by E.P. Simpson. It was located on the headwaters of the Tokoa Creek 1.7 miles northwest of the center of Tokoa, Stevens County, Georgia. The structure had a riveted steel penstock that extended from the dam to the powerhouse below. The waterfall to utilize the 280 foot head difference for power generation. The power plant went into operation the same year and was capable of a 200 kilowatt output. In the 1930s the Georgia Power Company purchased the local power distribution system passing the title of the dam, lake and power station to the Tokoa Falls Institute. The original dam height was increased in 1937 as power demands for more stable electricity increased. Between 1939 and 1940 the 38 high earthenfield dam called the Kelly Barnes dam was built on top of the original rock crib dam. Mr Kelly Barnes was the business manager for the Tokoa Falls Institute and that is how he got his name. Now I really need a dam named after me. The earth dam incorporated most of the old crib into its downstream tow. The structure was concave upstream filling a narrow portion to gorge formed by the Tokoa Creek. The impounded lake at normal pool elevation was approximately 40 acres holding back around 17 million cubic feet of water. An additional steel pipe was built to work as a low level spillway for the dam. During the works the power plant was also upgraded and masonry structures were built around this and the original penstock with valves controlling flow. An additional earthen spillway was added and this took the normal overflow of water. Post wall the dam was again heightened. Due to the works happening over the years no real design was really put on paper and this would prove difficult for investigators later on. The power plant was eventually shut down in 1957 leaving the dam and its lake for recreational use. After the dam was kind of left unattended with no official inspections or routine of maintenance. As such the main structure and its abutments became overgrown with bushes and trees. The foliage meant that the low-level spitway and penstock was visibly obstructed. During the early 1970s reports of continual seepage from the downstream slope of the dam near the points of the exit spillway pipe were made. At some point a large embankment slide had occurred on the downstream face around 1973. Neglected and not inspected the old earthen dam was arguably a disaster waiting to happen and that leads us onto 1977. During the period between November 2nd and November 5th around 3.2 inches of rainfall was experienced in the region. The water from the rain started to fill up the barn's reservoir bulging its banks. The rain got heavier during the evening of November 5th. At around 11.30pm volunteer workers went to the dam to inspect its condition from the rainfall and in the winter darkness all seemed well. Just a few hours later in the early hours of the 6th November 1977 at approximately 1.30am the Kelly barn's dam's main structure failed in the heavy rain. The failure released the water it held up down the Takoa creek on a collision course with the Takoa Falls Institute. One of the campus dorms would see the disaster's first victims as the tremendous power of the water swept through the area. In total 200 feet the dam had failed releasing at its peak flow 24,000 cubic feet per second washing away 9 houses, 18 house trailers, 2 college buildings and multiple vehicles. In total 39 would lose their lives during the event. Due to the time many residents were in bed asleep leaving little chance of reacting to the sudden flow of water. In addition to the human cost 5 houses and 5 college buildings were damaged. 2 bridges on Takoa Falls Drive and a culvert at County Farm Road were completely destroyed and Georgia's Route 77 which travelled through Takoa received considerable damage. The city itself saw some damage from the floodwater creating a local emergency. The water supply to the city was also damaged contaminating the drinking water for several days. A day after the disaster an investigation was ordered by Governor Busby appointing a task force on dam safety to look at the causes of the dam failure. The investigation was conducted by the US Geological Survey was concluded fairly quickly by December 1977 without a definitive reason for the failure. Instead several probable causes were settled upon. This wasn't so much the investigators thought as I mentioned earlier no proper plans or diagrams were made of the dam during its evolution leaving eyewitness accounts, historical photos and newspaper clippings to try and help build up a picture on the construction techniques used. Some of the causes for failure were linked with poor maintenance due to the dam's embankments being heavily vegetated with tree roots severely weakening the structure. This is likely as parts of the dam had slid from the original position in 1973 hinting that a similar situation could have been folded in 1977. The slide in 73 created tension cracks which could have further weakened the structure during the period of rainfall allowing seepage. Furthermore the long period of rain eroded away the downstream slope leading to a localised overtopping of the dam causing a chain reaction of more erosion and finally total structure failure. Another cited cause was that of the low level inlet pipe failing rupturing or becoming blocked leading to seepage and weakening of the structure from within. Although the exact causes are known one thing that is certain is that poor maintenance was the root cause as proper inspection and remediation work would have highlighted failure and stress points that needed to be addressed. What is most likely is that probably all of the highlighted causes contributed to the failure as the dam was weakened over a period of time. As a side note what is strange is that this disaster is another one I've covered on this channel under the Carter Administration. Regardless of the failure cause it is yet another reason why maintenance is very important be it your car or a dam. Thanks for watching I hope you enjoyed the video. This video is a plain difficult production all videos on the channel are created commons attribution share alike licensed. Plainly difficult videos are produced by me John in a sunny southeastern corner of London UK. Help the channel grow by liking commenting and subscribing. Check out my Twitter for all sorts of photos and odds and sods as well as hidden some future videos. I've got Patreon and YouTube membership as well so if you fancy supporting the channel financially you can there. Not what's left to say is thank you for watching. It's November 1955 and the world's first fast breeder reactor would experience a meltdown. The reactor designed and built to be a proof of concept would be successful however it would highlight the difficulties for such a reactor design type. The reactor a vital stepping stone in atomic history would be declared a national historic landmark in 1965. Reactor design is an evolution with several paths tracked along in the goal of creating more efficient and powerful units. Each path had a seed and one of these was the fast breeder reactor for EBR1. Okay I know I mixed up analogies there but you kind of get the idea. Almost every type of reactor has had a disaster or two and the fast reactor would be no exception. And as such I'm going to rate it here 5 on the painted plainly difficult disaster scale. But the EBR1 as a whole will get an 8 on the historical legacy scale because it is so important they turned it into a museum with other reactors parked outside. Our story starts in the late 1940s and a concept for a reactor that would create more fuel than it used. Walters in a Canadian American nuclear physicist on the urging on Orico Fermi set out to prove the theory with a small test unit. The reactor would employ a liquid metal coolant in the form of NAK which was a poor moderator but transferred heat efficiently ideal for the concept. You see a breeder reactor doesn't want a moderator to slow down the neutrons from fission instead using a blanket of fertile material to create more fuel. Construction began in 1949 at the Idaho National Laboratory in Idaho and it is around here on the map. The reactor had 217 fuel rods and 138 internal blanket rods used for breeding fuel. The unit had 8 safety and 4 control rods with the ability to scram shutting down the reactor placed around the outer section of the core. These were moved in and out by gears and used a magnet de-energizing for scram. The core was surrounded by graphite separated from the reactor by an air gap. Criticality was achieved in August 1951 with full power operation at 1.1 megawatts of thermal energy being reached on December 19th 1951. A day later the world's first electricity generated from nuclear power was achieved by powering four light bulbs via the plant's turbine. The next day the experiment was repeated and generated enough electricity to power the whole EBR1 facility. Although great this was it was also a bit of a sideline to the reactor's main goal which was breeding. An indication a year later would be seen to prove the scientists theory. In early 1953 laboratory analysis showed that EBR1 was creating more than one new atom of nuclear fuel for each atom burned. Fully powered up the reactor could create 1.2 megawatts of thermal energy that could be converted into 200 kilowatts of electrical energy which funnily enough was roughly the same produced by the power station at the Kelly Barnes Dam. In 1955 operators decided to test out the EBR1 to investigate issues highlighted during previous operations. What confused the scientists was that the reactor showed instabilities when coolant was at different flow rates. The test would involve the reactor at high power, intermediate power and very low power with varying levels of coolant rate. Basically seeing how the reactor well reacts to low coolant situations. To run the experiment the reactor would achieve criticality and gradually increasing power without coolant. We can probably see where this will end up. On November 29th 1955 operators at the EBR1 were about to undertake the test. The reactor was made critical at an initial power output of around 11 watts. The control rods were used to manage the power of the reactor up to 50 watts not long after 500 watts was being produced by the unit. As the power continued to rise the fuel rods temperature also began to rise more than normal. The power continued to increase and a shutdown signal was sent to the control rods to scram the core 500 seconds post initial power increase. For around two seconds the power level had gone off the maximum end of the instrumentation. Even though the signal had been sent by the control system the reactor power carried on increasing. Fearing the ramifications of this the operators manually activated a scram on the core. The reactor power finally dropped off eventually going sub-critical. From the control room the reactor seemed okay the coolant pumps were started up to try and dissipate the heat throughout the core. What the operators didn't know was that the core fuel had reached a temperature of 2170 degrees centigrade and have reached a power of 9 megawatts during the peak of the meltdown. In total between 40 and 50 percent of the fuel had been damaged during the excursion completely knackering the fuel loading of the EBR1 reactor. Not long after the NAK reactivity level alarm went off hinting at fuel melting and shortly after that health physics instruments indicated that there was air contamination in the building. Operators were evacuated from the building until proper surveys could be undertaken. Later surveys showed that low level radioactive gaseous had been released with minor thyroid gland activation in a few of the operating personnel. Post incident an attempt was made to remove the blanket and core elements from the reactor. Novel signs of fuel damage were found during initial removal of the blanket allowing extraction via the conventional way. When attempting to remove the rods containing fuel from the outer rows of the core considerable force was required by the technicians and damage to the jackets was observed and it only got worse from there. Due to the now observable damage it was decided that the whole core would be removed from the top of the reactor for further disassembly. Due to the extreme levels of radioactivity from the damaged core a cave was built around the unit on top of the reactor structure. The cave was constructed from 30 inch thick walls made of shield blocks faced with concrete blocks and thick shield windows. It was thought that this wall was thick enough to allow limited time for personnel to remove the fuel. When the cave was completed and necessary tools had been constructed the NAK coolant was sucked out of the core and proper disassembly began. The molten core alloy was found to have entered into the coolant channels and to have solidified into a mass surrounding the fuel section. All of this was covered in coolant. Sores had to be used to separate the fuel elements and this proved to be hard going work. After several small NAK fires resulting from removal of the outer fuel elements it was decided to stop further disassembly operations at the Idaho site and ship the core to the Le Mans site. A new cave containing a lower oxygen environment was built capable of containing 10,000 curies of one MEV gamma activity for final disassembly of the remaining fuel. To transport the damaged fuel to a hot cell a lead cask was used. The meltdown at the EBR-1 wasn't considered an accident as fuel melting was a known risk for the experiment and the core loading was nearly the end of its life expectancy. The meltdown did not lead to the end of the EBR-1 as a new fuel loading was installed into the unit. On the 22nd of November 1962 EBR-1 became the first reactor to produce electricity from a plutonium core but after 12 years of operation the unit was shut down in 1963. Lyndon B Johnson in 1965 listed the reactor as a national landmark virtually guaranteeing its place in history which is a museum to this day a definite place on my to visit list. Thanks for watching I hope you enjoyed the video this is a plainly difficult production all videos on the channel are creative commons attribution share alike licensed plain difficult videos are produced by me John in a sunny southeastern corner of London UK help the channel grow by liking commenting and subscribing also check out my twitter for all sorts of photos and odds and sods as well as hints on future videos I've got patreon and youtube membership as well so if you fancy check them out all that's left to say is thank you for watching a town that was once originally the dream of a nice summer resort would take a downward spiral to a low income suburb and ultimately a contaminated and abandoned lesson on waste disposal if you were to travel to this town today not much would tell you of the disaster that befell its residents but the story involves a lot of dioxin contaminated waste being sprayed on the roads of Times Beach Missouri. Times Beach has a strange story that was an odd side effect of the Vietnam War many thousands of miles from the battlefield in Missouri an unknowing contractor would spread deadly darks and contaminated oil as part of a dust reduction service for dirt tracks now I know this is an odd picture I'm painting but as I said Times Beach is a strange story and as such I'm going to rate it here seven on my patented plain difficult disaster scale and also seven on my historical legacy scale due to the seemingly obvious lessons that had to be learned our story starts with a newspaper advert in an effort that reminds me of London's metro land during the early 20th century a purchase of a plot at Times Beach came with a six month subscription of the st. Louis Times newspaper okay okay uh the comparison is a bit of a reach but it is similar in a sense that a company would sell you a lifestyle to further an ulterior company goal in Metroland's case it was to pay for new railways but in Times Beach's case it was an effort to prolong the newspaper's longevity the location of Times Beach was a 480 acre area around 17 miles west of st. Louis on the I-44 highway next to the Merrimack river and had previously been a flood plain used for farming because of one 20 feet by 100 feet lot in Times Beach was $67.50 but in reality to build anything worth habitation a couple of plots were needed the community was doomed from the start as the area was prone to flooding as such the properties were built on stilts and because you had to build a summer house yourself or get someone else to do it wasn't the uniform affair of modern day holiday results the community not long after its conception would have to bear the brunt like many other communities throughout the world of the great depression in the late 1920s understandably summer houses weren't necessarily a necessity during a period of economic downturn so those that could sold up however many didn't and instead took to living by the river to ride out the financial storm the community would once again get a kick in the stomach when during the second world war gasoline shortages would discourage many from visiting their holiday homes leading to more properties being sold off for permanent residency by the 1950s the area saw redevelopment with many of the summer houses rebuilt into low-income residential use the properties were not built on stilts as flooding had become a thing of the past the roads throughout the community were unmade dirt arrangements and this caused a pretty large nuisance for the residents and that is dust as a car trundles along a dirt road it unsurprisingly in dry weather kicks up dust into the air not great if you have clothing out on the line or are just generally outside and this problem had a solution that is probably tarmacking the road and maintaining it which is what didn't happen at times beach and instead old engine oil was used to suppress the dust kick up to be fair to the cash trap city paving the roads wasn't exactly affordable used oil is a cost effective solution but it doesn't exactly last forever and needs reapplication which is why someone can make some money out of servicing an area and this brings on waste hauler Russell Bliss Bliss's solution was to spray the roads around the community with waste oil at a bargain price of six cents per gallon and he would begin a job in 1972 but let's pause here because you might be thinking how has this got to do anything with the Vietnam war around 230 miles down the road in the rona Missouri a company called Hoffman Taft opened up a chemical production facility in 1949 the site was used to produce several different products including prist and aero fuel additive panterplex and animal feed fortifier and a more well-known chemical agent orange agent orange was an equal mixture of two phenoxy herbicides two four dichloro phenoxy acetic acid and two four five trichloro phenoxy acetic acid which contained traces of the dark sin two three seven eight tetrachloro dibenzyl p dioxin a deadly carcinogen the agent was used as a defoliant in an effort to try and deny the vietcong competence food and concealment often taffs started to experience financial difficulties towards the end of the 1960s and started to lease out some of its rona facility to the north eastern pharmaceuticals and chemicals company never co use the site to produce hexachloro theme an antibacterial agent used in soap toothpaste and disinfectants dioxin as we found out at Cefesso is highly toxic and can cause cancer reproductive and developmental problems damaged to the immune system and hormone interference the contaminants started to mount up on site a problem was created which was how to get rid of the dioxin the proper method was that of incineration but the rona site didn't have an incinerator meaning nepaco had to pay for disposal and this isn't cheap looking for a cheap alternative nepaco contracted independent petrochemical corporation to remove the contaminants a price was settled upon but ipc didn't have the experience in disposing of dioxin contaminated bottoms so the company subcontracted the work to rustle bliss the waste oil hauler that had a good thing going spraying dirt tracks bliss claimed later on that he wasn't aware of the toxic contamination or the materials he was paid to dispose of bliss took the dioxin contaminants to his facility and mixed it with the used oil for roadway spraying operations bliss also had a side business in training and breeding horses he found that his oil spray worked well in horse arenas and as such he had treated his own land with the oil this does make me think that he was unaware of the deadly chemicals he was using as why would you spray your own land bliss's oil spraying service impressed some of his horse breeding buddies as the mixture kept down a dust for a few months during may 1971 bliss's services were employed at a number of horse stables most notably the Shenadara stable located near Moscow mills Missouri what was odd was that bliss's oil was unusually thick and had a strange odor and many animals exposed to the treated soil would die including birds and eventually the prized equestrian livestock a month later in 1971 bliss was employed to spray at another stables near Jefferson city Missouri not long after a child developed chloracne and some of the horses became ill a third stables was also done around the same time all three sites suspecting bliss's operations ended up removing the topsoil around august the cdc got involved and took samples of the affected area but the results were inconclusive however they would conduct more tests finding trichlorofenol which can contain dioxin in the meantime bliss continued to spray waste oil anywhere he would get paid for and this leads us back to times beach between 1972 and 1976 bliss had been contracted to spray times beach is 16 odd miles unknowingly the sum 2000 residents would become exposed to the dioxin contaminated oil just like in 1971 times beach received a strange odor and saw birds dying of vicinity after bliss has sprayed his oil in total including times beach around 40 sites have been contracted by bliss to do dust treatment in Missouri whilst always was going on the cdc were trying to find the source to the mysterious illnesses reported in animals and local residents around Missouri the cdc searched for companies that had manufactured trichlorofenol and only one place was found nepaco in Verona now in 1972 nepaco had gone out of business due to the fda issue ban that limited the use of hexachlorofen which is a source of the byproduct dioxin the facility in Verona became fully under the control of syntax agribusiness leaving behind 4300 gallons of dark zinc contaminated bottoms in 1974 dark zinc poisoning was tied to the mysterious illnesses in the stables after a more in-depth sampling was ordered after the detection of trichlorofenol there was one link between all the contaminated sites and that was bliss but the investigators had to find a link between bliss and nepaco the closure of nepaco would reveal a deadly secret in 1979 which would finally give the cdc and the epa the missing link into the source of the contamination an ex-employee had blown the whistle on their old employer informing authorities about seven miles away from Verona dark zinc contaminated material had been illegally dumped in a farm the epa discovered 90 rusty seeping barrels buried at the farm revealing large quantities of dark zinc the dump site showed that nepaco wasn't adverse to just using anywhere or anyone for dumping bliss was questioned and claimed no knowledge of dark zinc but he did admit to being hired by ipc to dispose of the oils from the nepaco site the link was finally proven times beach wouldn't know the cause of the sickness until 1982 some 10 years after the first application of bliss's waste oil the information that times beach was one of the many contaminated sites from the dark zinc from Verona was leaked to the residents and the epa confirmed their suspicions but still needed to conduct more tests dark zinc was confirmed at times beach but things were going to get a whole lot worse for the town in early december 1982 the epa had conducted some initial testing but the Merrimack river had other ideas flooding almost the entire town and the area was inundated with backwaters from the river most of the residents had fled the town but if it wasn't bad enough the water had spread the dark zinc contaminated topsoil to almost every corner of the community by the time the floodwaters have receded the results were in from the epa's testing and dark zinc was found to be a hundred times that of a safe level the contamination was recorded at 0.3 parts per million by mid december some of the residents of times beach have returned to begin the drying and rehabilitation process but that wouldn't last for long on the 23rd of december 1982 the epa released the infamous christmas message if you're in town it is advisable that you leave and if you're out of town do not go back the message was essentially the death warrant for the community and on the 7th of january 1983 president ronald reagan created the times beach dark zinc task force on the 22nd of february 1983 the epa announced that the federal government would front 33 million of the estimated 36.7 million costs to buy out the residential properties and businesses of times beach leaving just under four million to be picked up by the state the site was placed on the superfund national priorities list two years later pretty much all of the residents of times beach had been bought out and relocated and now the abandoned town became the perfect location for the much needed incinerator to dispose of missouri's dioxin which would finally be completed in 1997 about 265 000 pounds of contaminated soil and debris from times beach and 28 other sites in missouri was burned after the completion of the incinerator activities and cleanup of the site the abandoned community was taken off the superfund national priorities list in 2001 the site today has been redeveloped into a state park called the route 66 park and there is also a visitor center on the site there's little much left to tell you that once a small community resided here as you can see here in the satellite photos that the town is pretty much gone not surprisingly nepaco ipc and bliss were hit with multiple lawsuits for the contamination all over missouri due to the error in which bliss operated he was not required to and did not record the sources of his waste operations and all throughout the event he claimed no knowledge of the dioxin contaminants but we will never know for sure nepaco and ipc had to pay out a lot of money as many lawsuits were brought against them and they had no excuse for not telling anyone what the oil contained syntex agribusiness the company that took over the verona site was fined 200 million dollars for their part in the disaster thanks for watching i hope you enjoyed the video this video is a plain difficult production all videos on the channel are creative commons share attribution like a licensed plain difficult videos are produced by me john in a sunny south eastern corner of london uk help the channel grow by liking commenting and subscribing check out my twitter for all sorts of photos and lots of sods as well as hints on future videos i've got patreon and youtube membership as well if you fancy supporting the channel financially all that's left to say is thank you for watching one of the series of dams in buffalo creek west virginia would fail causing a catastrophic domino effect releasing some 130 million gallons of black water down onto the residents some 250 feet below the disaster would cause a 10 to 20 feet high tidal wave washing down the creek and valley causing a death and destruction trail of 15 miles over a three hour period not only a local tragedy but the event would highlight the dangers of such storage operations and the coal industry as a whole the disaster would leave a cost of 50 million dollars in property damage and 15 million dollars in highway damage but more importantly 125 were killed and nearly 5000 made homeless today we look at the buffalo creek dam failure and subsequent flood on the 26th of february 1972 and as such i'm going to rate it here eight on the patented plain difficult disaster scale buffalo creek valley is in the southwestern corner of west virginia 40 miles south of charleston the area has been used for mining activities all the way back to 1900 development of the coal industry in the area increased when in 1914 a railway spur was built by 1920 the creek was peppered with small mining camps that would eventually develop into small communities once the land was sold off to private residents many of the people lived on the narrow flat flood plain of around 400 feet wide along the creek the hilly and narrow valleys of the area limited the overall population and because of this logan county as a whole only had a peak population in 1950 of around 77 000 in 1945 the lorado mining company opened mine number five and began activities in one of the forks off the creek named middle fork the waste from the on-site coal preparation plant was sent to the mouth of the middle fork building a large waste bank called bank one across the hollow now a preparation plant washes coal of soil and rock and crushes it into graded sized trunks the waste is largely coal contaminated water and soil in 1959 the company began pumping wastewater into the hollow behind the waste bank one to settle out solids from spent wash water the intention was to build a reservoir but the bank was too porous leading to water leaking out this problem was later solved in the 1960s when much finer waste from a local strip mine was added to the bank which did hold back much more water the mine was taken over by buffalo mining company in 1964 the water was decanted from the reservoir into a smaller clearwater pond for recycling for use in further preparation of coal by 1966 waste bank one went 1500 feet down the middle fork and was 200 feet high at the face of the buffalo creek a disaster in wales u k would cast doubt upon the bank's stability which would result in the survey 1966 as a side note abba fan is most certainly on my list of disasters to cover the year after inspection the bank grew in height by another 50 feet as more and more waste was dumped on site going into 1967 a new dam behind the clear pond was created from waste 600 feet upstream from the original bank by the end of the year the dam was extended allowing a 20 feet deep pool to form by 1969 this dam and pool was not enough and this necessitated the construction of a third dam this new dam number three was 600 feet upstream and was around 60 feet above the second dam in 1970 the pitstone coal company took over the operations on the site after extensive surveys of the buffalo mining company's properties it was given a thumbs up as safe by the new owners worryingly in 1971 pitstone was cited for over 5000 safety violations at its mines nationally by early 1972 dam three had extended 465 feet across the fork along its front downstream crest about 800 000 tons of coal waste had been dumped to form the dam and it was able to impound a pool of around 30 feet deep most of the dams in this area were only intended to hold water from rainfall or high levels of wastewater for shortish periods of time however for dam three the pond was often full to the brim during the construction of the dam trees and vegetation were not removed and instead just covered over with coal waste forming part of the upstream and downstream faces not only that but the waste had a foundation of sludge roughly around 50 feet thick the comparison dam two had a sludge base of 100 feet thick no segregation layering or zoning of the material used to build dam number three was undertaken to obtain maximum stability no type of spearway was built into the design instead relying on excess water seepage through the dam augmented by an overflow pipe another dam number four built further up the fork was around 200 feet long and had a crest of 40 feet over its highest side this construction did have a spillway however this brings us on to the 22nd of February 1972 and a clean bit of health of dam number three from the federal coal mine inspector but not more than four days later the structure would experience a total failure in the following days the region would experience rain showers worrying about the increase in dam three's pool water level company strip mine superintendent Jack Kent checked the levels with a measuring stick at the lowest portion of the dam on the 24th of February he discovered that the water stood just five feet below the dam's crest the rains continued and the following day the level increased by one to two inches per hour at 4 30 a.m on the 26th Kent found his measuring stick almost covered with the water just 12 inches below the lowest part of the dam's crest more worryingly the face of the dam was now oozing moisture at 5 30 a.m warnings were sent out to the local population by the sheriff's office half an hour later a team led by Kent went to the dam to attempt to create a relief pipe to try to reduce the water level the water from this pipe flowed over dam two but would prove to be too little too late leading up to 8 a.m the dam began to subside and slump allowing water to top over the crest at 8 o 5 a.m dam number three failed washing dams number one and two away the wall of water flooded the burning refuse dump causing an explosion the effulgence carried on down the fork to the valley of buffalo creek the flow of water further eroded the remains of dam number three increasing the speed of the release drainage of the pool continued until around 8 30 a.m around six million cubic feet of coal waste and other debris was carried downstream with around 90 percent of it escaping the middle fork with some reaching a distance of up to two miles the 10 to 20 foot high flood wave traveled along the 15 mile buffalo creek valley at an average speed of around five miles per hour finally reaching the town of man at around 11 a.m the disaster destroyed or damaged homes in saunders padi lorado londale stowe latrobe robinette amherstale beko vanco brayholm acoville crown and kissler in the immediate aftermath the disaster rescue operations and accurate reporting of the dead and missing were made difficult as access to the area by road had been disrupted with bridges destroyed and rail lines blocked or flooded 125 were killed and 1121 were injured and over 500 homes were uninhabitable leaving between 4 and 5 000 people homeless or without adequate shelter man high school was used as a temporary refugee location for buffalo creek survivors republican governor arch more announced the creation of a commission of inquiry to investigate the flood it was formed of nine members most of whom were sympathetic to the coal industry in response a citizens commission was set up to create an independent review of the disaster also the senate subcommittee on labour started an investigation in late may 1972 using experts from the us army corps of engineers who built a scale model of the valley including locations of the failed dams with so much destruction and death and an estimated damage cost in excess of 65 million dollars how did dam number three fail so catastrophically well much like the kelly barns dam which would fail five years later the banks in the middle fork didn't have an official design meaning construction was not to a uniform standard and was not properly inspected and maintained the united states department of the interior report highlighted five key causes for the failure of dam number three the first was that the dam was not built to withstand the amount of water in the pool this was due to the construction basically being a pile of dumped coal waste no spillway or other adequate water level controls were built into the dam on top of that there was no way for removing water once it had entered the pool behind the dam the small piping still during the evolution of the dam was insufficient and was too high to really make a difference third the sludge on which the dam was placed was inadequate as the foundation led to seepage and subsidence across the main structure fourth the whip for the dam was cited as an issue as it impeded any water through the bank leading to a large of an intended amount of water being held back this was because the dam was meant to be for water recycling instead of permanent retention and finally the fifth cause was the inadequate quality and grading of construction material which consisted of coal waste including fine coal shale clay and mine rubbish furthermore the pipe that had been placed inside the dam the one that was too high to make any difference also had a double failure of weakening the already poor material choice the ad hoc committee focused on improving legislation recommending all dams or impoundments constructed of coal refuse to be properly zoned for control of seepage rates requiring all dams or impoundments higher than 10 feet to be instrumented and monitored on a regular and frequent basis and requiring all dams or impoundments to have a full proof decant systems and or spillways designed by and constructed under the direction of a registered professional engineer with a completion in the design and construction of dams the citizens investigation was far more damning of the buffalo mining company and its later owners the pitstone coal group stating in its conclusions the company was grossly negligent in constructing and operating the refuse down on its property the company violated state and federal law since the dam was never approved for proper design and maintenance and the company's first concern has been to increase its profits by using the same refuse dam to dispose of clarified wastewater and store water needless to say the mining company would have a number of lawsuits to answer to in attempt to absolve itself of any blame pitstone coal put out a press release not long after the flood stating that the disaster was an act of god and the dam was incapable of holding the water god poured into it around 600 survivors of the flood sued pitstone coal company seeking 64 million dollars a settlement was later reached in june 1974 at a fraction of the cost of 13.4 million dollars roughly 82 million dollars in today's money another lawsuit brought on behalf of the child survivors which was again settled in june 74 for 4.8 million around 29 million today the state of west virginia also took pitstone to court for a hundred million dollar lawsuit to cover disaster and relief damages but governor arch a more settled the case for a measly one million dollars three days before leaving office in 1977 more had been accused during his time as governor of corruption and this settlement didn't do much to disprove it this left a bill around nine million dollars to be picked up by the state of west virginia to pay the us army core of engineers for recovery operations and what seems to be a very foul tasting trend with disasters of this type no criminal charges were brought against the company for their negligence we know the lessons were never properly learned from buffalo creek as the kingston fly ash spill would happen some 36 years later and there are still many coal impoundments that offer risk to the communities that live nearby thanks for watching i hope you enjoyed the video this is a plain difficult production all videos on the channel are created common share attributioner like licensed play difficult videos are produced by me john in a sunny southeast and corner of london uk help the channel grow by liking commenting and subscribing check out my twitter for all sorts of photos and odds and sods as well as hints on future videos i've got a patreon and youtube membership account if you'd like to support the channel financially and all that's left to say is thank you for watching mining is a dangerous industry for its workers from coal dust inhalation suffocation explosions and the obvious one mine collapse a collapse on the bed of the sesquihana river in pennsylvania united states highlighted the risks to the industry posed by improper execution of safety precautions the whole created would flood an entire mine complex swallowing up 10 billion us gallons of water and take the lives of 12 miners but also would be the parting shot of the ending of the coal industry in the region northwestern pennsylvania thoratics history has been intertwined with coal mining operations and isn't the first time this area has popped up in a plain difficult video of course i'm talking about centralia but today we're over in columbia's next door neighbor lazerne county our story starts back in 1762 with the first discovery of anthracite coal in the region this particular type of coal is sought after as it has the highest carbon content the fewest impurities and the highest density of all types the wyoming valley also known as the anthracite valley is canoe shaped about 25 miles long which extends from the counties of sesquihana and wane in the north to columbia county in the south with you guessed it lazerne slap bang in the middle when you see the township of jenkins on the map in relation to the anthracite valley it's not hard to see why the town had such a strong coal industry focus so much so that a small unincorporated community would be given the name port griffiths named after one of the original stockholders of the pencil vania coal company due to a number of mining disasters in the usa by the 1950s multiple safety regulations were in force in an effort to try and put disasters like the avondale mine disaster in 1870 to the past however the economic forces of lowering coal prices meant that the industry was in a slow decline long gone had the peak output of 100 million tons in 1917 as with most dying industries companies tried to squeeze out the last few drops of profit available by willfully ignoring or bending safety regulations and using old life expired equipment a side effect of this was the safety of those the managers sent to work every day in and around the port griffiths area multiple mine owners and contractor companies operated an intricate connected maze of mine shafts along and under the seshki hannah river incorporating winter moot and monoconic islands the nox coal company was one of these operations cutting costs and responsibilities at every turn the company was a contract mining operation these organizations mined on behalf of the mine owner which allowed shall we say streamlining of operations the nox coal company had begun leasing the riverslope mine from the pennsylvania coal company in may 1954 the company hired 174 men 23 surface workers and 151 underground workers the mining operations were to exploit the pitstone and marsy veins which contained the juicy anthracite production from nox coal was around 700 tons per day which was hand transferred to chain or shaking conveyors the main workings for the company was through two entrances to the mines the riverslope and the main shaft three other shafts operated by other companies were available for emergency exit from the complex the riverslope was dug into the ground 240 feet long at an angle of around 25 degrees where intersected the pitstone vein the main shaft was 332 feet deep and the other three emergency shafts were the halt shaft at 528 feet deep the school east shaft at 579 feet and the eagle air shaft at just 60 feet the mining operations employed the chamber and pillar method which looks like this in order to get the sweet sweet coal out of the pillars a recovery method was used this involved filling the gap with waste material and then mining the pillar but this was only allowed when authorized by the landowners and can be very dangerous the mines were rather close to the sesquihana river and this necessitated some rules and regulations in regards to how close the miners could get to the riverbed the maps of the mines had things called stop lines where mining could not take place because of inadequate roof thickness this not-to-be-pass line gave a 50 feet safety margin between mine wall and river the nox coal company requested a 35 foot margin which government officials approved this wouldn't be enough and eventually the company would keep pushing the boundaries to chase the anthracite veins until the point of no return two illegally dug gangways were extended under the river 125 feet past the officially and clearly designated stop lines the workings then sharply turned up to follow the pitstone vein on january 22nd 1959 the nox coal companies disregard for rules would finally come back to bite them in the morning a team of 81 miners descended down the river slope for another day's work in the dusty mine various teams split off along the various corridors to the different seams management with the backing of the workers union had been asking the workers to dig well beyond the stop lines eventually reaching just 19 inches of the icy cold january sesquihana river some of the workers in the marsy vein were told to put down some loose roof material and put in some timber at around 11 30 a.m a timber prop cracked one of the workers informed the foreman who then went back to check the pitstone vein at 11 42 the roof gave in to the way to the river above the assistant foreman telephoned the colliery who then in turn sent out the emergency warning for everyone to evacuate the mine the call was also sent out to the adjacent mines who withdrew their workers 22 escaped through the may shaft some by the time they had made their escape had to wade through the flooding tunnels 11 men escaped via the hoitz shaft and three left via the river slope 33 made it to safety via the abandoned eagle air shaft in total 12 were trapped behind in the icy cold water below the breach had created a hole in the riverbed with millions of gallons gushing down the power of the water swept away the timber supports of various workings by the afternoon of the 22nd works were underway to fill the hole as the western railway line of the lee valley was broken and diverted to near the breakthrough this was rather strange as not only rubble and waste was to be poured into the hole but the railway carriages themselves anything that could be thrown in was including the aforementioned carriages mine carts boulders hay and any other rubble available a few days later on the 25th of January the water flow was stemmed somewhat which allowed rocks and earth to be placed in the semicircle around the hole two sinking pumps were installed in the mines to try and begin the drying process these would later be joined by another 22 shaft pumps bulkheads were placed inside the mine near the breach and above ground two cofferdams were built starting in March completing in May the same year the dams went from the shoreline to winter me island on the eastern side above and below the breach area a third dam was built on the island to completely divert the water away from the area tons of clay and rock were poured into the hole and a concrete cap was placed on top of the opening a lot of water was pumped from the flooded mines but none of the 12 missing men were ever found but as with any disaster like this we need to look at how the breach could have happened in the first place and spoiler alert it involved corruption federal mine inspections in 1958 had taken a look down the mines but no sign of any wrongdoing was found unfortunately this would be wrong inspections made by the Pennsylvania Coal Company during 1958 had actually highlighted Knox's coals passing of the stop line but no remediation action was taken it was found that Knox Coal had not only passed the line but was also working in an area that needed permission from Pennsylvania Coal which unsurprisingly was not given there was another main factor for the failure and that was the water itself due to the time of year the sesquihanna river was partially frozen over which contributed to an increased water level the higher level increased the weight on the already weakened riverbed during investigations post incident it was found that one of the labor union leaders had shares in the company which is obviously a conflict of interest as well as a blatant violation of american labor law for disaster inquiries eventually led to charges against the 11 top bosses at the Knox Coal Company the Pennsylvania Coal Company and the united mine workers of america the charges varied from manslaughter to bribery but yet again no one would actually serve prison time after numerous trials and appeals three bosses at Knox Coal did eventually serve some time but not for the deaths at the river slope but instead for tax evasion the disaster put a spotlight on the corruption and dodgy dealings with the coal industry in the region resulting in probes into other company's operations and it was found that Knox Coal was not unique but disaster accelerated the end days of deep mining of coal in the anthracite valley not only did it cause significant damage to the mines but attempts to plug the hole used up valuable equipment i kind of imagine it's similar to fixing a flat tire by throwing out the rim and replacing it with the steering wheel which needless to say is a bad idea thanks for watching i hope you enjoyed the video this video is a plainly difficult production all videos on the channel are creative commons share attribution are like licensed plainly cropped videos are produced by me john in a sunny southeast in corner of london uk help the channel grow by liking commenting and subscribing check out my twitter for all sorts of photos and odds and sods as well as hints for future videos i've got patreon and youtube membership as well if you fancy supporting the channel financially not that's enough to say is thank you for watching when mary shelly penned frankenstein she envisioned the risks of scientific discovery as a warning for pushing the boundaries beyond what a person can take responsibility for shelly may not have realized but science would almost catch up to her just over 150 years later the experiment in today's video was something that could have been a prototype for frankenstein's monster and that is the transplant of a head from one body to another but as with many experiments involving animals there is an efficacy gray area where the lines are blurred between what is butchery and what is not the experiments covered in this video is essentially the vivisection of multiple animals and can be argued for the good and bad of scientific discovery welcome to a new series of plain difficult videos where we have a look at some of the more ethically rocky scientific experiments head transplants have fascinated doctors for a long time imagine giving a paraplegic person the chance to regain their body independence back being able to make use of a body that would otherwise be buried or cremated to give someone a new chance at a more normal life it's possibly one of the final frontiers of organ transplants a science that has brought back many from death's door today we are looking at the infamous 1917 monkey head transplant conducted by robert joseph white although the experiment sounds like the stuff of nightmares the study did help push forward experience and knowledge in organ transplants and because this is a new series we've got a new scale and that's the ethical scale 10 being legit evil and one being for the greater good of mankind as such i'm going to rate the monkey head transplant a six purely because it's so grim and i'm pretty squeamish our story starts 18 years before robert white was born and the first dog head transplantation by american physiologist dr charles guffrey and french surgeon dr alexis correll the surgery involved attaching a decapitated dog's head to another dog's neck with the blood first flowing via the donor dog's head to the live victim the experiment was a proof of concept as the donor head showed some reaction to stimulus but due to 20 minutes of blood loss during surgery the extra new head deteriorated quickly the test dog was put down shortly after the blood had started to cause brain damage and this would be the biggest hurdle to a head transplant the two doctors although arguably failing at this experiment did use their knowledge to further organ transplant science earning them a noble peace prize a few years later our next journey through the gruesome history of head transplants next stops in the 1950s and not surprisingly the soviet union with a doctor vladimir demikov in 1953 demikov made strides in coronary bypass surgery having successfully completed such experiments on four dogs that lived over two years post surgery which in all books is a success demikov turned his sights on the ultimate in surgery and obviously that's going to be head transplants in 1954 demikov achieved better results in East Germany than guffrey and carol allowing the donor dog head to be able to lap water be more aware of its surroundings and have limited movement the surgery involved grafting the upper body including front legs and head onto the other dog demikov did several experiments with multiple dogs the longest for any subject survived post surgery was 29 days but most died within a few days the process that was used preserved the blood flow to the donor head hence more functionality post surgery the limitations of survival of the dogs was mainly due to immune response of the recipient to the donor causing death the next major challenge of head transplantation involved immunity suppressive agent development enter stage right robert j white the one who would do the infamous monkey head transplant white in 1965 had started to experiment with the concept of head transplants although he focused more on isolated brain transplants and the difficulties in keeping the flow of blood he created vascular loops to preserve blood flow between the internal maxillary and internal carotid arteries of the donor dog this meant that the brain has uninterrupted blood flow even after severing the second cervical vertebrae the method was named by white as auto profusion using this method white was able to successfully graph six canine brains to the cervical vasculature of six other dogs although the surgeries were successful the dogs lived between six hours and two days post experiment using monitoring equipment implanted in the brains showed good oxygen and glucose consumption meaning they had a good metabolic state post surgery the experiment showed the feasibility of short term isolated brain transplant although pretty gruesome the methods learned meant white could attempt a monkey head transplant on the 14th of march 1970 white would conduct his experiment for the experiment white accepted that like all other head transplants to date but the donor body would be paralyzed because of this the isolated body would have to be kept in function by mechanical and chemical stimulation of the heart and lungs this was due to the complexity of re-establishing the nerve stem but the main goal was to keep the brain function to a similar level post op to pre op whites experiment used eight small rhesus monkeys for a total of four experiments each of the four experiments would have monkey a's head attached to monkey b's body the experiment used whites auto profusion technique and reattachment surgery which had been perfected in the lead up to 1970 the operating room team even used marks on the ground to choreograph each and every move of everyone in the theater the rhesus monkey was chosen because the animal would give the most accurate representation of a human like central nervous system the monkeys way between six and seven pounds were initially put under intravenous pentobarbital then each head for transplant was instrumented with EEG's and the recipient bodies were instrumented with ECG once this was completed the monkeys were tracheotomized and was servically transected at the level of the fourth and fifth cerebral vertebrae at the same time preserving the carotid jugular circulations the preservation of blood flow was done through sutured can your loops during previous experiments it was found that just one carotid artery and jugular vein was enough to provide blood flow for the head even after all other circulatory support have been severed this was completed under constant monitoring for the transplant to the new body one the cannula loops was stopped and connected to the body and after blood flow was resumed the second cannula was stopped and connected to the new body this allowed constant blood flow to the brain extra blood had been drawn from other monkeys in case of any hemorrhaging during the surgery antibiotics were under constant supply along with immune suppressive agents to help prevent rejection of the new body head combination three to four hours post surgery the monkey heads would start to show awareness of their surroundings with their eyes following stimulus and would even attempt to eat any food placed in the mouth the EEG records reflected that the establishment of a characteristic consciousness state and in a grim way the faces as seen here look rather scared of the situation which obviously is understandable if blood pressure fell so did the heads awareness a dye was used to mark the blood brain barrier the muscles in the face were active and looked like they were working as they should in fact looking at the footage you wouldn't even think that the head had been amputated the bodies did not show signs of rejection of their new heads probably because the amount of drugs pumped into the bodies each of the four experiments lived between six and 36 hours post surgery eventually the mixture of drugs and blood loss from the amputation area killed off each monkey after the experiment each brain was dissected and showed no signs of brain damage or dye infiltration proving the concept of a head transplant the monkey head surgery showed that cephalic or full body transplant was possible and even though the longest of any of the monkey's lives was just over a day with extra time taken on suturing with modern techniques of today the surgery could have been a much more longer term experiment white became well known after the experiments and took a lot of flak from animal rights groups and even his peers although it did not seem to really affect his accomplishments as a neurosurgeon who within his career perform over 10,000 surgeries albeit on human subjects he would pass away in 2010 at the age of 84 the lessons learned from the experiments helped further transplant science which by the 1990s had more improved mixtures of immunosuppressive agents which had hindered the monkey's life expectancy post surgery in 1970 the new drugs were a key factor when the first human face graft proved successful head transplants did not die with whites however as the mantle was taken up by Xiaoping Ren who grafted the head of a mouse onto another mouse's body which survived the six months post surgery and in 2013 Sergio Canavero published a method that he said would make a human head transplant possible by 2017 but that never happened so take that with a pinch of salt where would you rate the monkey head experiments on my ethical scale one being it's all good and ten being the work of pure nightmares thank you for watching this is a bit of a new subject choice for me and a pilot of sorts of a new series would you like to see more videos like this then let me know in the comments below play the cool videos are creative commons attribution share alike licensed and are made by me john inner not at the moment so sunny corner of southeast in london you can check me out on twitter for odds and sods and for those of you want to give me any money you can at patreon youtube membership or paypal and all that's left to say is thank you for watching before we start i should probably say that this video is based off the joint accident investigation commission's report into the incident there has been subsequent theories into the cause of the disaster stemming from more recent discovery of a hole in the ship's starboard side of its hull and more modern 3d scanning of the vessel's resting place the theories have surmised that the cause could have been an explosion or even a collision with a submarine right without disclaimer out of the way here's the video ships are truly impressive pieces of engineering defiantly navigating the immeasurable power of the sea when you are near one on land the vast size of such machines gives the impression that such a large structure of steel would be unsinkable but as history has proven this is most certainly not the case and a cruel merciless sea can swallow such vessels and hundreds of lives aboard the sinking of the estonia would be the third worst loss of life at sea on board an european ship during peacetime only being beaten by the rms titanic and rms empress of ireland there is one major difference that sets the estonia aside however and that is that she didn't collide with another ship or iceberg but instead the power of the waves themselves caused a major failure of one of her components that allowed her to operate as a car ferry on the 28th of september 1994 within an hour over 15 000 tons and 852 lives would be lost beneath the waves of the Baltic sea today we're going to rate this disaster here five on my patented essentially now arbitrary plainly difficult disaster scale our story may end in 1994 but it began all the way back in 1979 and the need for a new vessel for the rapidly expanding ferry industry in the Baltic sea a contract was signed for a new ferry on the 11th of september 1979 and was set to be built by mayer werft in paperburg germany the ship which had her killed late in october 1979 was to be built to similar specifications of the diana 2 in order to speed up construction by using a similar design her story was turbulent from the start after the original customer a norwegian shipping company led by parley augustin pulled out of the contract luckily ruderi ab sally one of the partners in the viking line consortium was more than happy to take over the project the new ship was recalled the viking sally the name stonia came along later on in her operating life as part of the new owner specifications the length of the ship was extended from 137 meters to 155 meters and along with this came a new superstructure design one such design feature from the diana 2 that was retained was a hinged bow visor that opened upwards enabling vehicle access to the car deck various parts of the ship were built by different contractors however the vital bow visor was installed by mayer von tell ab was the supplier of the visor parts used to lock and operate the machinery the machinery was actually manufactured by another company grimoire's verxtad's ab and all details communication and changes were made through von tell as the middleman the bureau very test rules gave no detailed guidance for calculations for the visor from vertical and longitudinal sea loads and as such von tell and mayer used their own estimations and it is unknown if the two companies compared notes the visor including attachment devices was built of grade a mild carbon steel and was set up in a way that meant the visor couldn't be operated unless the ramp was fully closed the visor pivoted around two hinges on the upper deck and was locked in place by three hydraulically operated devices which were two side mounted and one bottom mounted and it also had two manual locking devices she had a passenger capacity of around 2000 people maximum service speed of 21 knots maximum deadweight draft of 3006 deadweight tons and four man engines creating a combined power of around 23,000 horsepower the ship was built to the rules and regulations of the finished maritime administration the Viking Sally was pressed into service between turku and marinham in finland and stockhome like most ships the Sally had its share of screw-ups including a couple of murders propeller issues and the grounding her owners radiri ab Sally were experiencing financial difficulties towards the end of the 80s and were sold to the Finnish swedish group F John but still operated under the Viking line under her original name she did fully come under the control of her new owners in 1990 when she was painted in Celia lines colors renamed the Celia star but remained on the same route the new name would only last a year or so until she was transferred to the wasa line another subsidiary of the F John group and was placed in the wasa line operation in the Gulf of Bothnia for the new operations she was now called the wasa king in 1991 that was until the 14th of january 1993 when she would change flags from Finland which she was originally delivered to the flag of Estonia this coincided with a new owner the esteline marine company limited and a new name the ms Estonia she was pressed into service on the Tallinn Stockholm route at the time she was the largest ship in the Estonia national fleet and became a symbol somewhat of the country's independence after the dissolution of the eastern block right that leads us to 1994 and the Estonia departing from Tallinn on the 27th of september 1994 at 7 15 p.m for a scheduled voyage to Stockholm and her estimated time arrival was 9 a.m on the 28th of september she carried 989 people 803 of whom were passengers leading to remaining 186 being crew upon clearing the harbour all four engines were powered up for full speed and she began her journey sea conditions along the Estonian coast were moderate but became worse when she joined the open waters the weather continued to worsen with winds increasing to 15 to 20 meters a second causing two to four meter high waves which crashed across the Estonia's bow as the ship got thrashed around some passengers became seasick at around 25 past 12 in the morning and at a speed of about 14 knots the vessel encountered the crashing on her port bow at around one o'clock in the morning a metallic bang from the bow area as the vessel hit a heavy wave was heard from the car deck by a member of the crew the crew member informed the bridge of the strange noise after inspecting the indicator lamps all seemed well the ship did not slow down after the report and the crew on deck didn't make use of a cctv link to the car deck to investigate the area of the loud bang roughly about the same time a shift changeover happened on the bridge and soon after another report of a loud metallic bang from the bow came in at around 105 the seaman of the watch was sent down again to inspect the visor but just 10 minutes later the visor separated from the bow and tilted over the stern the ramp was pulled open allowing water to surge into the car deck the water caused a heavy starboard list and at the same time dramatically slowing the ship down estonia's distress beacons had to be activated manually which the crew failed to release throughout the ship panic set in amongst the passengers with many attempting to rush up the staircases although many were still trapped inside their cabins life jackets were distributed to passengers who managed to reach the boat deck some jumped or were swept into the sea and a few made it onto life rafts that had been launched due to the list of the ship lifeboats can be deployed and at around 1.20 in the morning a fake pa announcement saying alarm alarm there is alarm on the ship was broadcast at 1.22 the first mayday call from estonia was sent and a general alarm to crew for lifeboats was announced by 1.24 multiple radio stations on both ship and land received the calls around the same time the four engines stopped running causing a backup generator to power up but this left much of the ship unlit further adding to the panic flooding of the accommodation happened at an alarming speed and the starboard side of the ship was submerged at around 1.30 as the ship continued to flood the list increased to 90 degrees as she sank beneath the waves the stern went first disappearing from radar in the area at around 1.50 the location was about 22 nautical miles from uto island finland within the hour four passenger ferries had arrived on the scene of the accident and started to search out and rescue survivors it wouldn't be for over an hour before vital helicopter support would arrive the mounting efforts rescued 138 people from the waters throughout the night and early morning of the 28th of september after the living the remaining search efforts found 94 bodies over the next few days with such a tragic loss of life and the sinking of a thought to be reliable and safe vessel investigators were faced with the question how did the estonia sink most of the victims went down with the ship to the seabed she was found in international waters on the 30th of september within finland search and rescue region resting on the seabed at a water depth of around 80 meters it was vital that the cause of the sinking be found as the estonia was one of many similar ships operating in the region with reports of noise from the bow visor hinting at a failure point a remotely operated vehicle survey was decided on to ascertain the ship's general condition and whether the bow visor had become detached during early october the rov made several videotapes of the wreck and the results were shocking during investigation into the sinking it was found that the bow visor and ramp had been torn off as it failed to resist the power of the waves hitting against it the first metallic bang heard around one o'clock in the morning was thought to have been the sound of the visor's lower locking mechanism failing and other reported noises were the visor flapping against a hole as the other locks failed as a cruel twist of fate an amounting bracket for the locking bolt position sensors appeared to be undamaged this meant that even after failure there was no warning to the bridge of the now open visor this was even more compounded by the design of the bridge which was too low to have a line of sight to the visor meaning there was no way of seeing the state of the visor even after the catastrophic failure during investigation another incident a year before was highlighted which would have been a vital warning sign in 1993 the diana 2 of stonia's kind of sister ship had experienced a visor locking failure as the starboard locking device lug was lost the bottom lock was bent with its welds cracked and the port side locking device lug was bent with its weld also cracked she was repaired and the incident was not considered serious enough to need a general notice via the bureau veritas regional office in gothenberg the investigation concluded that the visor was insufficiently designed to withstand realistic load levels this was due to limited experience of the industry to hydrodynamic loads on bale visors because of this both the shipyards and the equipment supply used their own and flawed calculations the full width open car deck contributed to the rapid increase in list when flooded which resulted in the estonia's capsizing and sinking the action of the crew speeded up the ship's demise if they had used the cctv link to the car deck they would have been able to see the water rapidly flooding in this coupled with the slowing down of the speed of the ship after reports of strange sounds could have slowed or even prevented the sinking soundingly alarm aboard the ship and the seemingly lack of direction of the crew was highlighted by the investigators and was thought to be a contributing factor of the panic by the passengers the loss of the estonia held a mirror up to the shipping industry in the region necessitating new vessels from 2010 to be able to withstand their car deck being flooded up to 50 centimeters all ships post accidents had to be modified to release their emergency beacons automatically and life raft regulations for rescue from listing ships in rough water were introduced but that is little consolation to the 852 that lost their lives that september night thanks for watching i hope you enjoyed the video this video is a plain difficult production all videos on the channel are creative commons attribution share like licensed plain difficult videos are produced by me john in a sunny southeast in corner of london uk help the channel grow by liking commenting and subscribing check out my twitter for all sorts of photos and odds and sods as well as hints on future videos i've got patreon and youtube membership as well if you fancy supporting the channel financially all that's left to say is thank you for watching 1986 is the year that would change everything in the nuclear industry a disaster would burn the concept of atomic fallout into the zeitgeist of the 1980s and the legacy would act as a constant reminder of the risks of improper management of a nuclear reactor the disaster became a testament on how poor design and mismanagement when placed in a venn diagram can equal a radiating most of eastern europe of course today we are looking at the chenobyl disaster of 1986 and this one has earned the magical 10 on my painted plain difficult disaster scale believe it or not this video is actually part of a series of videos on the chenobyl disaster and in a wider context the rbmk reactor type and in light of that it might be worth checking out my video on the leningrad and other chenobyl meltdown don't worry i'll still be here when you get back ah you're back welcome yep i know it was a bit of an overdone trope so let's get back to the main reason why you're here our story starts back in 1970 and in ukraine about 100 kilometers 62 miles from Kiev when ground was broken for a new city that would become known as pripyat an atom grad that was designed to house the workers for a new nuclear plant it should be said that the original plans were to build the city and the plant just 25 kilometers or 16 miles from Kiev but it was thought to be too close to a major city which turned out to be a good decision the concept of an atom grad is similar to say tombsk which were closed cities although pripyat was open later on in its short lifetime as a city these municipalities were designed to be self-contained communities that had a sole purpose and that was keeping the power plant working and by extension the workers that were employed there happy the community at pripyat was developed to be the perfect home for a young family with its amusement park and modern at the time architecture in the same year the ground where the new plant would exist was prepared for construction the chenobal nuclear power plant began construction proper in 1972 after the central government decides on what type of reactors the site would house originally the idea for a pressurized water reactor was thought to suit the new plant but it was overruled by ala tolly alexandrov the chief scientist who was at the time supervisor of the project of rbmk reactor plants the reactor type was preferred due to the design being cheaper to produce and as we found out with leningrad that cost was a pretty high priority some might say even over safety the nuclear power plant had the first of its four reactors ready to operate in 1977 followed by number two in 1978 as a quick side note units one and two were the first generation rbmk 1000 reactors and because of this they had slightly different core loadings and containment structures but the remaining two reactors at chenobal were of a slightly more modern second generation and they were named units three and four which went online in 1981 and 1983 respectively there were plans for another two units but these were abandoned after 1988 when risks of contamination left the project untenable the nameplate capacity of chenobal nuclear power plant was unit one at 800 megawatts of electricity unit two at 1000 megawatts of electricity unit three also had a thousand watts of electricity and the same with unit four in this video i'll be focusing on the second generation rbmk its design and more specifically unit four but i did look into the first generation in the leningrad video the rbmk was a bit of a unique design in the reactor world but it was a product of evolution rather than revolution in that it used graphite to moderate the chain reaction with light water as a coolant this combination allowed it to use low enrichment uranium 235 for fuel which is not surprisingly significantly cheaper than other reactor designs the rbmk had a very large core region consisting of a height of seven meters and a diameter of 11.8 meters which was mounted in a steel cylinder that was placed on top of a biological shield the steel cylinder was 16 millimeters thick and had a diameter of 14.52 meters by a height of 9.75 meters dug into the floor of the reactor building inside a reinforced concrete line pit between the steel wall and the concrete lining a water tank was placed followed by a sand packing below the bottom biological shield there were several basements used for pipe work for the reactor core cooling loops the core consisted of graphite blocks sized 25 by 25 centimeters stacked up with holes drilled through the center for fuel and control channels the size of the core could issues in reactivity control during operation but we will talk about that a bit later on on top of the core another biological shield was placed with a steel cover on top of it which formed the floor of the reactor hall the cover plate was capable of withstanding a pressure buildup resulting from steam released by two simultaneous channel ruptures all of this allowed the design to be refueled whilst in operation which again helped with costs by reducing downtime as a side effect of this the confinement structure of rbmk reactors is less than ideal as the tall refueling machine had to be housed inside the reactor hall because of the large floor space and subsequent roof requirements meant that the vast quantities of heavy concrete wouldn't have been architecturally or more importantly financially viable the rbmk didn't have a prototype and was instead put straight into production with the first reactor being installed in leningrad in 1970 the original designs omitted confinement instead claiming that the fuel being in its own channel with flowing cooling water was an acceptable alternative the main takeaway from this is confinement was poor resulting in disastrous results in the case of efficient product release the coolant was pumped through the core from the bottom common header through high pressure tube that jacketed the fuel elements where the water would boil coolant water also circulated in the control rod channels the primary cooling of the reactor was via two separate cooling circuits one of each for half of the core meaning everything was doubled up leading to four main circulating pumps which were three operating and one standby per loop as the coolant boils it exits the top of the core and is passed through a water steam separator which takes the steam to a high then low pressure turbines which generate electricity the steam is then passed through a condenser that turns it back into water to be pumped back into the core completing the primary cooling circuit the condenser is called by using a separate secondary water cooling circuit meaning the primary cooling circuit is self-contained as mentioned before the reactor employed graphite blocks for its moderator now moderator is used to reduce the speed of fast neutrons released from fission so they can better facilitate a chain reaction getting more use out of the fuel ideally moderators work without capturing any neutrons leaving them as thermal neutrons the way the design has its potential flaw is having a separate coolant that can also absorb neutrons which can make the reactor unstable in certain situations this brings up the big elephant in the room and that is void coefficient you see it wasn't just a graphite that had moderation characteristics but the coolant water as well because h2o naturally slows down and absorbs neutrons this brings a problem for the reactor as with the increase in temperature from fission the coolant boils off into steam known as voids i.e a bubble that does not absorb neutrons with the steam not absorbing neutrons this leads to an increase in the power of the reactor the rbmk did not rely solely on its coolant for moderation because that's what the graphite was for but the water did absorb neutrons meaning that as it boiled off the operators had to compensate for this with the control system if not properly managed an incident of a runaway can happen as the coolant heats up increasing reactivity heating up the coolant more creating more steam leading to greater reactivity and this is called a feedback loop due to its reactor state more and more neutrons are produced and their density grows exponentially fast creating a positive void coefficient the risks of a feedback loop were greater at certain power levels but this will be covered later on the design relied heavily on the void coefficient for its reactivity this is unlike a pwr setup in which the coolant is also the sole moderator meaning the chain reaction can't be sustained if all the coolant has boiled off creating a more stable design but this is also much more expensive now this leads us quite neatly on to reactor control as i said before the core region was rather big and this meant that the rbmk was kind of like multiple smaller reactors in that hot spots could occur which needed to be individually managed and this leads on to the strange design choice for both top loaded and bottom loaded control rods there were 167 top loaded rods and 32 shortened rods loaded via the bottom and another 12 automatic controls inserted from the top the shortened rods were used to manage axial power distribution which was necessary due to the core size to manage hot spots the main control rods had a 4.5 meter long graphite rod termed a displacer attached to the end of the length for the control rods except for the 12 rods that we use in automatic control the displacer connected to its rod via a telescope with a water filled space of 1.25 meters separating the displacer and absorbing rod this was to stop water filling the space left behind by the control rod after it has left the core region which would parasitically absorb neutrons because removing one neutron absorber in the form of a boron control rod to be replaced by another neutron absorber albeit weaker in the form of h2o kind of defeats the point of the control rod thus if there was no displacer then more control rods would be needed as each one would have less of an effect on the reactivity of the core the dimensions of the rod and displacer were that when the control rod was fully extracted the displacer sat centrally within the fueled region of the core with 1.25 meters of water at either end but this set up in certain situations could cause a positive scram effect on receipt of a scram signal causing a fully withdrawn rod to fall water was displaced from the lower part of the channel as the rod moved downwards this caused a localized insertion of positive reactivity in the lower part of the core this was because the rbmk had a high moderated to fuel ratio meaning the lower part of the core would experience a spike in reactivity as the graphite displacer entered it as it replaced the neutron absorbing water with a neutron moderating graphite but this situation was only dangerous at certain power levels of the reactor which was meant to be mitigated by the knowledge and training of the operators and also importantly by their management part of this mitigation was by having an operating reactivity margin the orm is the number of equivalent control rods of nominal worth remaining in the core the total time required for a scram or insertion of the emergency control rods into the core when starting from the upper limit stop switches was around 18 seconds which was relatively slow but this was due to the size of the control rod channels and the fact that the coolant had to be pushed out of the way the scram could be initiated by the control system or manually via the az 5 button the control system employed on the rbmk 1000 utilized ionizing chambers and various sensors both inside the core and outside which were effective from power levels above 10 percent of total power the external detectors were all mounted mid level of the core meaning no low actual power monitoring could be undertaken this meant that low power operation below 10 percent had to be done by the operators relying on experience and feel than monitoring the equipment but manual low power control was only really intended for a cold startup so to speak when the reactor was free of the neutron absorbing poison zenon 135 right i need to mention about neutron poison as it will play a vital part later on and was also a contributory factor in another rbmk incident the meltdown in leningrad in 1975 during fission some products are given off one of which is zenon 135 which has a high neutron absorption rate which is okay when the reactor is in a steady state as it burns off this undesired byproduct as poison burning is proportional to reactor power but when the power of the reactor is decreased the zenon 135 is not burned off and can shut down the chain reaction by absorbing too many neutrons this is known as an iodine pit all is not lost as zenon 135 has a relatively short half-life of around 9.2 hours so reactor core is considered poison free after several half-lives have passed but this is not good from an economic standpoint as the unit would be shut down for a few days which is where good management is meant to come into effect where safety is prioritized over money but in the form of ussr taking a reactor out of action for a few days could have a detrimental effect on one's career longevity our story starts with an issue inherent to all reactors of any type a thing called decay heat you see reactors produce heat from fission which is used to create steam to drive the turbines for electrical power some of this power is taken to drive the electronically operated coolant pumps which keep the coolant flowing through the core the reactor needs around 28 000 litres per hour during full power operation some heat is produced not directly from fission but instead from the products produced from the chain reaction and this is known as decay heat and when the reaction stops this continues at least for a while after shutdown during power operation this is fine as electricity is being produced but after shutdown the pumps need to keep circulating to remove the decay heat usually electricity needed for the pumps can be drawn from the national grid but what about if there is a full power outage then backup is needed this presents a problem if for any reason being scheduled or not a reactor is shut down and there is a power cut how will the pumps keep working well the solution is pretty simple and that is a diesel backup generator each of Chernobyl's reactors had three backup diesel generators which took in excess of 70 seconds to reach full power too much time in the event of a full power cut in theory some of this time could be covered by the spool down of the turbo generators which was theorised to cover around 45 seconds not the full time needed but possibly enough to prevent fuel melting to prove that this could work it had to be tested out and in 1982 1984 and 1985 this was attempted but all tests failed to produce the electricity needed to run the pumps the test was to be conducted again in April 1986 strangely the test procedure that was written hadn't taken into account the eccentricities of the rbmk reactor especially at low power outputs the test was to be conducted during a routine shutdown but the test to go ahead some vital systems had to be switched off most notably the active passive emergency cooling system used in a loss of cooling accident this required the chief engineer to sign it off in preparation for the test the following had to be set up the reactor power was to be reduced to between 700 and 1000 megawatts of thermal energy and the steam turbine generator was to be at normal operating speed after all this was sorted the preparations for the electrical test could go ahead the steam supply to the turbine generator would be closed off the turbine generator performance would then be monitored to see if it could bridge the power for coolant pumps until the emergency diesel generators took over when the emergency generators supply electrical power the turbine generator will be allowed to continue freewheeling down the normal plan shutdown procedure of the reactor was then to be completed the date of the test was to be the 25th of April 1986 15 minutes past 2 p.m completed by the day shift as such the operators were briefed on the procedure and a team of electrical engineers was present at around 1 a.m on the 25th of April the reactor was gradually powered down to around 50% in time for the day shift at 105 p.m the turbo generator tg7 was switched off the four main circulating pumps two electrical feed water pumps and other electrical equipment that was connected with this turbo generator were switched over to bus bars for the turbo generator tg8 the eccs was disabled with the correct authorization from the chief engineer but just after 2 p.m the Kiev electrical controller asked for the test to be postponed to cover the evening electrical peak demand the request was due to another power station in the region unexpectedly going offline genobals director agreed and the test was pushed back but the eccs was not reinstated the status of the eccs showed the lack of safety culture at the plant although the system wouldn't really be a factor in the disaster it highlights the management culture at the time the day shift soon gave way to the evening shift which in turn was soon to be replaced by the night shift to oversee the test annatoly dyatlov deputy chief engineer took the helm in the control room due to his seniority he outranked all operational staff on shift at the time alexander akimov was the chief of the night shift and lenid topchnov was the operator responsible for the reactor's operational regimen and the movement of the control rods at around 2300 hours the Kiev electrical controller allowed the continuation of the reactor shutdown and by 10 past 2300 hours the reactor power was brought down to 700 megawatts of thermal energy the night shift operators had to prepare for the test in a short period of time inferior to the test was completed the team would have a straightforward night just monitoring the decay heat until the next crew change over as the power dropped off the high amounts of iodine 135 decayed into the poison xenon 135 as it was not being burned off quick enough this produced the power of the reactor without any operator intervention to 500 megawatts of thermal energy at which point manual intervention was started in order to maintain the level at 28 minutes past 12 on the 26th of april the reactor power had dropped to just 30 megawatts of thermal energy with a near shutdown like state it is not 100% known why but both equipment failure and operator error have been attributed to the reactor state as set out in the operating instructions the reactor should have been powered down to wait for the xenon 135 to decay but shutting down the reactor without doing the test wouldn't have made many friends in management to increase the power the control rods began to be removed to try and overcome the poisoning of the core reduced coolant void and graphite cooldown in the attempts to raise the power the operational reactivity margin was violated by removing more of the absorbing control rods and by 1 a.m around 200 megawatts of thermal energy was reached the reactor was now in a dangerous state not wanting to leave empty handed diatlov insisted that the test be conducted at the current power level in reality the core was heavily poisoned and was in a dangerous state with very few absorbing rods for emergency control during the preparations of the test the operators powered up the two backup coolant pumps leading to all eight working the increase in water flow reduced the voids within the core which would have set off an automatic scram but this was bypassed by the operators as the coolant absorbed the neutrons in the core only eight control rods were left as a safety margin the minimum that the orm stipulated was that around 28 rods should have been in the core the reactor started to experience a feedback loop with not many rods in the core to manage the power the situation was that the water in the reactor found itself being the main neutral absorber and disaster was just waiting to happen at 1.23 in the morning the actual test had now begun the command given to stop the valves for turbine number eight closed and the rundown operation started as the turbines spooled down the power to the feed water pump slowed increasing the temperature of the coolant creating more voids with less water absorbing neutrons the power of the reactor began to rise a feedback loop was beginning to start in the lower part of the reactor core the operators pressed the az5 button in response to the worrying increase in power and the control rods started their travel into the reactor core as the control rod attached graphite displaces moved down to the lower part of the core in their control channels the neutron absorbing water was pushed out of the way creating a momentary spike in power replacing it with neutron moderating graphite during the spike some of the fuel rods ruptured blocking the control columns stopping the control rods at 1.3 insertion this left the graphite water displaces stuck in the lower part of the core increasing the runaway power excursion within three seconds the reactor power rose to 530 megawatts of thermal energy in the control room a few shocks were felt and the control rod indicators showed that the insertion had stopped as the channel pipes began to rupture mass steam generation occurred as a result of depressurization of the reactor cooling circuit bission materials leaked into the coolant and steam pressure grew inside the core as the coolant boiled off creating a greater neutron population the reactor power hit 30 000 megawatts of thermal energy although it is thought that the power could have gone much higher than that during the excursion the steam blew off the top steel cover and top biological shield of the reactor as more than the two design fuel channels failed releasing debris into the reactor building this was what would later be described as the first explosion but it would not be the last a second more powerful explosion occurred between two and three seconds later and this destroyed the roof and ejected super heated pieces of graphite out of the reactor hall peppering the area around the building with shrapnel some red hot material fell onto the roof of the machine hall and started a fire it is thought that around 25 percent of the core material was ejected but now uncovered reactor core mixed with the outside air and ignited a graphite fire a blue glow could be seen outside the reactor building from ionizing radiation emitting from unit four there was nothing left at the reactor confinement structure which meant little stopped the harmful contamination from escaping some of the debris that was ejected started a fire on the roof of reactor 3's building but insanely the unit wasn't shut down straight away instead the operators were told to take iodine tablets and don't respirators at 1.45 in the morning the first responders from the Chernobyl fire team arrived under the command of lieutenant vladimir previc and began trying to extinguish the flames on unit 3's roof all around them laid pieces of unit four's graphite core the firefighters were only aware of the fire and because of this they didn't have any radiological protective clothing on as they worked they breathed in some of the fission material in the form of dust and were exposed to the deadly radiation many would come down with acute radiation sickness shortly after some of the first responders fell to metallic taste in their mouths similar to what others had reported post exposure for example from the victim of the wood river junction criticality the fires on the roofs of units three and four were under control between 10 past two and 20 past two in the morning and the fire was fully put out at five o'clock in the morning having a graphite fire in what was once unit four continue to burn expelling its radioactive plume of dust steam and smoke into the atmosphere the operator started to pump water into the core but this did little to bring the situation under control the estimated dose of five to six runkins per second was experienced around some parts of the reactor building which is equivalent to more than 20,000 runkins per hour which is enough to give you a lethal dose in minutes the effective dose to meter monitoring of the operators was unavailable when the two 1,000 runkin per second capable meters were inoperable the only remaining meters maxed out at 0.001 runkins per second which immediately read off the scale when used meaning that no one in the control room actually knew what they had received the poor awareness of the dangers they were in left the operators believing that the core was still intact crew chief alexandra akimov stayed in the building until the morning ordering staff to try and pump water into the core many of these workers would be dead within a few weeks you see the rbmk core was generally fought by staff to be incapable of becoming uncovered and as such the blatant evidence to the opposite was ignored at 2 pm on the 26th of April an announcement that you would never want to hear was broadcast in the city of propiette for the attention of the residents of propiette the city council informs you that due to the accident at the chenobal power station in the city of propiette the radioactive conditions in the vicinity are deteriorating the communist party its officials and the armed forces are taking necessary steps to combat this nevertheless with the view to keep people safe and as healthy as possible the children being top priority we need to temporarily evacuate the citizens in the nearest towns of Kiev region for those reasons starting from the 27th of April 1986 at 2 pm each apartment block will be able to have a bus at its disposal supervised by police and city officials the first to leave the town was women and children and within three hours the city was empty a ghost town and left to decay but this will be a subject of another video emergency accident management operation began on the 28th of April the first priority was to try and tackle the radioactive material release the first attempts were to try and put out the graphite fire to try and put out the fire multiple items were to be dropped into the core each item that was to be dropped over the core was intended to tackle each different part of the fire and the radioactive release first the radiological side was tackled by dumping a total of 5000 tons including about 40 tons of boron carbide 2400 tons of lead and 1800 tons of sand clay and 800 tons of dolomite the method of deployment was to be via helicopter initially the first pilots received high doses as they hovered above the uncovered core the pilots were then ordered to fly over the core dumping during the flight which reduced pilot exposure but reduced the effectiveness of each sortie and had the side effect of damaging the remaining structures and actually spread the contamination even more in total 1800 sorties were flown they didn't do much and even worked as a thermal insulator increasing the fuel damage Boris Trebina became the soviet crisis management supervisor and Valery Legazov from the Kurchatov Institute of Atomic Energy became a key advisor of the government commission formed to investigate the cause of the disaster and to plan the mitigation of its consequences initially the soviet government wanted to not make the disaster public but that couldn't stay a secret for long radiation alarms were set off all over europe and unsurprisingly questions were beginning to be asked at around the same time as the helicopters were dumping material on the reactor the USSR officially admitted to an incident at Chernobyl at around 9 p.m a 22nd broadcast the first of its type was announced the firefighting efforts and pumping of coolant water left the basement flooded which caused another potential disastrous outcome another steam explosion you see the fuel from the core was melting towards the basement which had flooded but below that was more water from the bubbler pools which was a large water reservoir for the emergency cooling pumps and as a pressure suppression system needed to say that this was the next point of focus for the accident management team engineers Alexei Ananikov and Valery Bezpolov and supervisor Boris Baranov volunteered to empty the bubbler pools this was done by valves controlling sluice gates which were housed in a room that had now become flooded all three men donned protective suits and breathing equipment and made their way down the corridor the men were successful and the bubbler pools began to empty surprisingly all three survived not only the day but continued to live long after the disaster averting the immediate steam explosion but that wasn't the end to the worry of a deadly explosion as described in the film china syndrome the core could continue to melt through the floor of the containment and into the earth eventually hitting the water table meaning another steam explosion the next focus of the accident management team was stopping the molten core from escaping the bottom of the reactor basement a design that was fought up by physicist Leonard Bolshov that involved digging out a cavity below the reactor building basement the concept used coiled formation of pipes cooled with water and covered on top with a thermally conductive graphite layer the graphite cooling plate was to be encapsulated between two sacrificial concrete layers each one a meter thick in theory as the molten uranium oxide hit the graphite it was to rapidly cool down catching the core meltdown thankfully the theory didn't have to be put into practice as the core had finally come to rest in one of the lower basements of the reactor building part of which formed the famous elephants foot which was discovered in December 1986 which had a reactivity of 8,000 runcans or 80 grays per hour for reference a whole body dose of around five grays can be lethal the molten material is known as corium and is a mixture of the material found inside the core and is mainly made up of silicon dark side with traces of uranium graphite zirconium and titanium the excavated cavity and cooling system now unneeded was filled with concrete to help the structural integrity of the heavily damaged reactor building a plan was conceived to contain the contamination release of unit four in the form of a concrete lid which would come to be known as the sarcophagus construction began in May 1986 24 days after the disaster to encapsulate some 200 tons of radioactive corium 30 tons of highly contaminated dust and 16 tons of uranium and plutonium the construction would last for 206 days between June to late November of the same year but before the core could be enclosed under sarcophagus the next phase of remediation was to remove all the core material that scattered the area and one of the most dangerous places was the roofs of the building surrounding unit four initially robots were thought to be able to undertake the clearing works but due to radiation interference only around 10% of the debris could be recovered this necessitated the use of good old-fashioned people the most basic of equipment was needed for the task which included protective clothing and a shovel a toast of 5000 people known as liquidators were called upon to undertake the cleanup on the roof each only being allowed between 45 to 90 seconds of total working time to reduce the risk of exposure the calculated risk was 25 rem or 250 millisieverts of radiation per person there were many more liquidators also used for other clearing up works in the wider area and finally after this the sarcophagus could be closed over the turbine hall and reactor building the construction was undertaken over eight stages all whilst unit four released contamination and next to unit three was still needed to be operable concrete containment walls were built around unit four and a dividing was erected between it and unit three the sarcophagus was placed on top of the concrete containment walls more than 400 000 cubic meters of concrete and 7300 tons of metal were used during the construction of the sarcophagus the building encapsulated an estimated 740 000 cubic meters of heavily contaminated debris together with contaminated soil holes were installed in the structure to allow pressure release albeit through a filtration system the shelf life of the structure was only thought to be around 20 to 30 years necessitating a new containment structure but this will probably be covered in the next video in this series so with an official death toll of 31 a nuclear power plant essentially unusable and many decades ahead of remediation works how was unit four allowed to be operated in such a dangerous state unsurprisingly it comes down to management the warning signs of the potential for fuel damage in an rbmk 1000 reactor reared their heads several times the reactor types history a partial fuel melting in leningrad over 10 years before in 1975 had been covered up and information was not passed on to other rbmk operational staff at different power plants again the fuel melting incident that happened in 1982 at chenobu unit one no less was also covered up this time by victor brookanov meaning lessons again were not passed on the risks of a positive effect of scram causing a power spike were known in december 1983 at ignalia unit one unlike other incidents involving rbmk's the information from the event was passed on to other plants but were thought to have not been important enough to act on as the control rods didn't get stuck and did continue to stop the reaction the iaa was involved in the investigation into the disaster using the international nuclear safety advisory group which had been created by the iaa in 1985 all of the reports have never been able to categorically say for 100 percent what the cause of the core uncovering was and there is much speculation to whether the power excursion happened pre or post scram but operating the reactor in the state it was in meant that something was going to fail regardless of the inherent floor designs of the rbmk it was operated way out of the agree parameters even set by the lax soviet nuclear industry it can be attributed to the culture of working where failure was not accepted and vital operating incidents were not learned from as well as this the design floors were outright covered up and held back from the operators in 1987 a criminal trial was brought against five plant employees between the 7th and 30th of july in a temporary courtroom set up in the house of culture in the city of chenoble ukraine they were deputy chief engineer anatoly diatlov chenoble plant director victor brookanov the former chief engineer nicolai m fomin the shift director of reactor four boris rogozin and chief of reactor four alexander kovilenko three other men alexander akimov lenid topchenov and velary peber vizienko would have been tried as well but the cases were dropped after their deaths due to radiation exposure they were all found guilty of varying charges from criminal mismanagement of potentially explosive enterprises to negligence receiving between 10 and 2 years amongst them diatlov who was in charge during the test was given 10 years would only serve a fraction of this being released due to bad health he would die in 1995 from complications from his exposure brookanov who had helped cover up the partial meltdown at unit number one in 1982 was also given 10 years but still lives to this day and also served a shorter term in his sentence even though i suppose the perpetrators were punished the culture of the ussr nuclear industry meant that rules were regularly and blatantly broken and overlooked especially when it came to important things like the orm which ultimately put the reactor in such a deadly state this was all highlighted in the 1992 in sag seven reports which also said in its summary the plant fell well short of the safety standards in effect when it was designed and even incorporated unsafe features compounded by inadequate and effective information between both operators and between operators and designers there was an inadequate understanding by operators of the safety aspects of their plant also affected by insufficient respect on the parts of the operators for the formal requirements of operational and test procedures the industry in ussr had an insufficiently effective regulatory regime in place to counter pressures for production the pressures from central government and lack of awareness of the design risks of the reactor meant that management acted dangerously in the false pretense that the rbmk was indestructible pretty much the entire management structure was throwing around a grenade that they didn't know had the pin pulled out of meaning disaster was only a matter of time now i'll be following up this video with another video at some point about the wider impact of the disaster on local and wider population as well as digging deeper into liquidators and their heroic work thanks for watching i hope you enjoyed the video this video is a plain difficult production all videos on the channel are created commons attribution share alike licensed plain difficult videos are produced by me john in a sunny south eastern corner of london uk help the channel grow by liking commenting and subscribing check out my twitter for all sorts of photos nods and sods as well as hit some switcher videos i've got patreon and youtube membership as well so if you fancy checking them out feel free to and all that's left to say is thank you for watching structural failures can usually be categorized into two groups the first being financial for example cutting corners during construction improper maintenance or just outright corruption but the second category is more psychological and that is constructing whilst ignoring any potential warnings large scale projects are always susceptible to a type of thinking resulting in construction completion with a safety compromise structure this is known as completion bias and can create a tunnel vision effect where warning signs are missed due to so much time and money being invested in a project a great example of this is in the private pilot realm where the embarrassment or need to reach a destination results in continuing to fly in poor or outright dangerous weather conditions which has sadly many a time resulted in disaster the effect has been seen several times in the dam construction industry which have resulted in disasters for example like the villon dam where geological warnings were missed resulting in a catastrophic overtopping and flood today we're looking at the titan dam failure which will result in eleven dead thirteen thousand cattle killed a hundred million dollars in construction costs and over three hundred million dollars in claims for remediation our story starts all the way back into the early 1960s and the perceived need for a new dam to be situated three miles north of new dale idaho on the titan river the area had experienced a severe drought in 1961 followed by severe flooding in 1962 and the bureau of reclamation set about to try and tackle this whilst also bringing other benefits of a dam to the region the titan basin project as it was to be known would include a new earth and dam to impound a new reservoir for the generation of electricity flood control irrigation of farmland and recreational activities the reservoir will extend 17 miles upstream holding back around 288 000 acre feet of water with a surface area of 2100 acres the area selected for the new dam was in a canyon that had been carved out by the titan river in the snake river plain the plain was almost entirely underlain by 1.9 million year old balsalt and rhyolite both of which aren't the best foundation material for a new dam due to their high permeability regardless the bureau of reclamation continued on with the project around a hundred core drills were bored at a future dam site between 1961 and 1970 and highlighted the need for further investigation of the site some leakage tests were undertaken on the planned right hand abutment side and showed no water leak from the abutment however the levels of water in the surrounding holes did rise this led to tv camera investigation which showed many cracks and joints of random orientation but a left abutment investigations into its suitability involved grouting into the rock to see the effectiveness of filling the cracks in the foundations initially all seemed acceptable and the information was passed along to the designers of the dam in 1963 the project was authorized and by 1971 after initial planning an environmental impact statement was produced the project would have many objections after this initial statement and this was for many reasons brought by locals and environmental conservationists this was due to the ecological impact on the local areas wildlife as with any feeling of a reservoir a large area now finds itself underwater on the 27th of september 1971 several environmental and conservation groups brought a lawsuit in idaho district court to stop the construction amongst the environmental complaints were also a strong economical one stating that the return on investment from the dam wouldn't be all that great not only that but questions were raised over the geological suitability of the area for a dam the lawsuit and concerns delayed the tender for the construction contract at least for a while but eventually morrison nudson co of boys assisted by pete kewitt and sons of oma har nebraska won the bid in december 1971 with initial construction works to begin in early 1972 the suit would be dismissed in 1974 just two years before the disaster but that would only be the start of the warning signs for the suitability of the project but first let's have a look at the design of the teaton dam the plans for the dam were made under the direction of the office of design and construction at the u.s. bureau of reclamation at their denver federal center it was to be an earthen type field dam using soil dug from the reservoir location the designers were aware of the surveys which highlighted seepage issues and planned for excavation to groutable rock slush grouting under the core outside the key trenches and downstream holes or tunnels a continuous grout curtain along the entire foundation was to be used extending about a thousand feet into the right abutment at about 500 feet into the left abutment the dam centerline was straight for 2000 feet of its length and curved upstream on the right abutment for the last 700 feet also on the right abutment was the spillway which had a gated chute structure with an auxiliary inlet and outlet for each abutment a trench had to be cut into the rock sides of the canyon there was a river outlet underneath the left abutment which took water from the reservoir bed for use at the pumping and power station the dam's embankment consisted of five zones zone one was the center core and was the largest part which took the longest to construct the center of the dam was a mixture of clay silt sand gravel and cobbles tightly compacted by tamping rollers to form a core this was fought by the bureau of reclamation engineers to be impervious to water next came zone two which was placed over the core and composed of sandy gravel compacted to an average relative density greater than 70 percent zone two was extended downstream across the floodplain and on the abutments underlying zone three zone three consisted of miscellaneous fill zone four was similar in construction to zone two and served as the upstream cofferdam zone five was rock fill in the outer parts of the embankment all zones created an overall height of 305 feet above the riverbed right let's get onto the construction which began in february 1972 initially the spillway and key trenches were excavated initially river flow was directed through the middle of the canyon so that excavation could proceed on both abutments after this was completed the river was again diverted into a channel along the right abutment to allow the cutoff trench to the left of the channel to be dug warning signs were found during these initial works as large open fissures were discovered during excavation of the key trench near the right end of the dam several voids were found and had to be filled in with portland cement with some of the fissures actually being caves which resulted in more work than originally thought at this point the structural suitability of the foundation should have come into question but with so much time and money poured into the project so far it just had to be completed the entire embankment foundation was stripped of all unsuitable material including boulders loose rock and topsoil in january 1973 a us geological survey team inspected the site and sent a memo to the bureau of reclamation saying safety of the teaton dam project is of immediate concern and pressures from the filled reservoir and loading could trigger movement that would endanger the dam the bureau's head of design and construction how g alpha rebutted these concerns asserting that the teaton site lay in a favorable area from a seismic standpoint which directly contradicted the us geological survey during the 1973 construction season the cutoff trench in the river channel was completed as was the grouting in the lower part of the foundation the river was diverted once again through the outlet works on the 8th of june 1973 this diversion enabled construction of the cutoff trench on the right side and the placement of the embankment on the trench towards the end of the year the first of the zone one material was placed in the foundation trench on the 3rd of october 1975 the river was diverted again when the auxiliary outlet was put into operation to enable placement of second stage concrete in the intake and gate chamber of the river outlet and to install outlet gates pipe penstock manifold and metal work and equipment the zone one area was completed in 1975 allowing the remaining material for the dam's embankment to be placed on top throughout the rest of the year were construction completed in november 1975 with this newly constructed dam the next thing was to fill the reservoir behind it the us bureau of reclamation set out to monitor the performance of the foundations and structure during the filling process this was to ensure that the dam was safe for operation part of his monitoring was checking the face of the dam for seepage as well as checking the waterboard downstream for any abnormal rises the plan was to have the reservoir productive for irrigation in 1976 and open to the public by 1977 with the initial filling rate to begin at one foot per day the reservoir bed was at around five thousand and fifty feet in elevation that as the water level rose the reservoir surface elevation would also rise by march the reservoir water surface was at an elevation of five thousand one hundred and sixty seven feet the auxiliary outlet was releasing water at 295 cubic feet per second the director of design received a memorandum from the construction engineer that would be worrying wells that have been dug for water table observation had shown a significant rise but it was felt that it wasn't anything to worry about as the dam had been inspected and no leaks were found on the 23rd of march the allowable filling rate was increased from one to two feet per day because the river outlet work was still incomplete and the runoff from the Teton river was abnormally high the reason for the high runoff was due to increase snowfall in January that had melted increasing the flow rate the reservoir was allowed to rise in height as the spillway was thought to have been able to handle any flooding from the eleventh of may until june the fifth the average rate of rise was at three feet per day with a maximum of four point three feet on the 18th of may the redwire level continued to rise up to the maximum depth of 240 feet on the third of june 1976 seepage was discovered in small springs in the right abutment on the downstream toe of the dam they were flowing water at approximately 40 to 60 us gallons per minute what was strange was that the flow of liquid was clear and not brown in color which was more common of erosion on the fourth more leaks were found on the right abutment again flowing clear water at approximately 20 us gallons per minute more seepage was discovered on the fifth of june around 730 in the morning but this time the water color was that dreaded brownish but due to the clear water before the engineers did not believe there was a problem a wet spot on the downstream face began eroding its way into the abutment on the right side of the dam two bulldozers were sent down to try and fill the leak which is this really small dot on this photo at around 10 14 the morning an emergency call to prepare for flooding was made to the madison and fremont county sheriff's office at around 11 a.m one the bulldozers started sliding into the opening the other bulldozer attempted to pull it out between 11 and 11 30 a.m the project office called the sheriffs again and told them to evacuate the region immediately something that definitely can't be a good thing to see appeared at around 11 30 a.m and that was an increasingly big whirlpool in the reservoir near the right hand side of the dam the two bulldozers on the abutment started to sink into the opening and both operators abandoned their machines in the meantime two more bulldozers attempted to block the whirlpool by dumping material but this yielded no results the flow for the opening continued to increase until 11 55 a.m when the dam began to breach at the crest just two minutes later total failure had begun as the reservoir waters broke through the teat and dam and rolled downstream the water carried away about four million cubic yards of the embankment bearing the power and pumping plant beneath over two million cubic feet per second of water emptied through the breach into the last six miles of the teat and canyon from there the flood spread out into the snake river plain a 15 feet high wall of water sped along at around 10 to 15 miles an hour hitting and decimating the towns of wilford and sugar city the water then swept through a log mill which added debris to the flow resulting in the city of rexburg being battered by 8 p.m the reservoir had completely emptied leaving around two-thirds of the main dam structure remaining on the 6th of june president gerald ford declared bingham bonville fremont madison and jefferson counties a federal disaster area 11 people were dead with five of which being wilford residents luckily a higher death toll was averted by the evacuation warning but regardless the property damage was immense which leaves us a question how did this multimillion dollar brand new dam fail immediately after the failure reclamation commissioner gilbert g stan an assistant secretary of the interior arrived in idaho to inspect the site two investigation panels were set up but like most dam failures eyewitness testimony had to be relied upon due to most of the evidence being washed away during the breach however excavations of the remaining parts of the dam did yield some hints at the failure mode a house of representative subcommittee was also set up headed by leo ryan the same man that would tragically be killed in gianna in 1978 by jim jones followers the hearing and investigations highlighted the dubious selection of the dam site due to the permeability and porousness of the rock in the valley the likely cause of failure as stated in the independent panel to review the cause of the teaton dam failure theorized that piping was caused by erosion of the dam via the porous nature and open joints of the rock at the dam site stating it was recognized by the usbr early in design and confirmed by the panel's investigation that zone one material placed in the key trench and against the abutments was highly erodible as a reservoir level rose the hydrostatic pressures in the upstream jointed rock increased to a point that would have been sufficient to cause hydraulic fracturing resulting in main structure erosion congressman ryan was concerned with a thing he called momentum theory which is similar to completion bias which was endemic in the government organization where the bureau of reclamation had never stopped a project after construction had begun this was especially true for teaton where the us geological survey had highlighted key faults with the site selection in 1973 but a project already in construction went ahead regardless the speed at which the reservoir was filled became a point of criticism as if the filling had been slower than the near three to four feet per day at its peak then the project employees could have highlighted and fixed any issues but the bureau eager to complete the project allowed for a higher fill rate even though not all the outlets were finished the grout curtain came under criticism as well saying that it was inadequate for its purpose as well as the use of a narrow foundation main trench after excavation of the remains of the dam more wet spots were discovered showing that defences built into the design to prevent water penetration were inadequate all the investigations came across similar conclusions it is best summed up in the independent panel investigation summary stating the fundamental cause of the failure may be regarded as a combination of geological factors and design decisions that taken together permitted the failure to develop finally saying in final summary under difficult conditions that called for the best judgment and experience of engineering profession an unfortunate choice of design measures together with less than conventional precautions was taken to ensure the adequate functioning of the teaton dam and these conditions ultimately led to its failure if the bureau had stepped back not focused on the end point and taken in the whole picture during construction then maybe they would have seen the dangerous situation they were creating but unfortunately they focused on the destination and not the journey the financial ramifications of the disaster would run into billions and unsurprisingly a number of suits would be brought against the bureau of reclamation before responsibility for the teaton dam's failure was decided a week after the disaster president Gerald Ford requested $200 million for initial payments for damages the cleanup works began almost immediately but the long-term effects were disastrous the ecosystem downstream from the dam was wiped out affecting trout populations the bureau of reclamation set up offices in rexburg idaho falls and blackfoot for the purpose of people to make financial claims from the government by the end of the process in 1987 over 7500 claims were made totaling $322 million the dam was never rebuilt and remained a ruin which became a testament to the pitfalls of completion at all costs this video is a plain difficult production all videos on the channel are creative commons attribution share alike licensed plain difficult videos are produced by me john in a kind of sunny south eastern corner of london uk help the channel grow by liking commenting and subscribing check out my twitter for all sorts of photos and odds and sods as well as hints on future videos i've got patreon and youtube membership as well if you fancy supporting the channel financially and all that's left to say is thank you for watching the bond between mother and child can be unbreakable the complex relationship is difficult to quantify as when does it begin in the womb postpartum regardless the relationship in nature is vital for the life expectancy of the infant as without a caregiver food and security are not secured but what if we could boil the mother child relationship down to its basic components perceive security comfort and nourishment that is what today's topic sought out to explore the nature of love although the experiments did not test the human mother child bond it did try out on one of our closest cousins i must warn you of the subject matter in this video although a fascinating dive into the psychology of motherhood it does involve despair sadness and arguably horrific results for the test animals taking this into account i'm going to rate it here four on my ethical scale the reference one is completely fine and 10 being just outright evil i've given this number due to the experiment not being as detrimental to the monkey's health as say the head trance plants were although in some cases severe psychological trauma was inflicted on the test subjects of course this video is about the controversial monkey mother studies by harry harlow welcome to the dark side of science in 1981 the scientific community mourned the passing of a psychologist whose studies became a fascinating and sometimes controversial dive into animal psychology before we get into the experiments in the late 1950s our story starts in fairfield iowa in 1905 with the birth of harry israel the third or four brothers in 1924 he began to study psychology at stanford university being taught by a couple of notable scientists one of whom would shape the young psychologist's future career during his university career israel was under the watchful eye of louis terman developer of the stanford binna iq test he received his phd in 1930 and under the advice of his mentor harry changed his last name from israel to harlow harlow started working at the university of wisconsin madison he had asked for the laboratory space but this was denied this was due to the university's animal testing laboratory being torn down initially wanting to study on rats harlow then gained access to henry villas zoo where he discovered the primates there would be preferable to rodents for his studies in 1944 he left the university and worked various different jobs in the scientific community including being the president of division of experimental psychology at the american psychological association and head of division of anthropology and psychology at the national research council he returned to madison university in 1956 and took the role of director of the primate lab he was offered an abandoned building on the campus for his studies this old rundown structure would be the location of his controversial studies into monkeys during his work using monkeys he devised several problem solving and intelligence tests proving that by mere curiosity alone the subjects would want to solve the puzzle his studies would develop into different intelligence tests for a whole range of age groups but he had a problem and that was a reliable source of infant and developing monkeys harlow set up a rhesus macaque monkey breeding colony to gain access to developing primates for his experiments by doing so his experiments would take a different course part of his program employed rearing the monkeys in a nursery away from their mothers which is a controversial method but harlow had found it hard to do intelligence tests on infant monkeys with their mother around he noticed a staggering difference between his reared infants compared to their mother reared peers most notably their behaviour as they were reclusive had little in the form of social skills and took comfort from holding onto their cloth diaper cage linings they also found that the subjects would experience severe stress and anxiety when the diapers were removed from their cages during routine cleaning harlow and his students were fulfilling the infant's physical needs but the team soon noticed the psychological deficiencies from nursery rearing he also noticed that the infants that were mother reared but socially isolated from other monkeys also showed strange behaviour either being introverted or aggressive when introduced to others were the infants taking comfort from their cloth diaper cage linings harlow thought that this was due to the lack of a maternal figure and would become the basis of a new experiment the concept of the monkey mother would begin to form in 1957 when harlow covered a wire frame in a rough shape of a monkey with a diaper cloth the new test apparatus was thought to be the minimum requirement for a recess monkey in terms of contact comfort now this leads us on to the monkey mother experiment and harlow's famous paper the nature of love harlow set out to study the development of affectional responses of neonatal and infant monkeys to an artificial inanimate mother the study would create two types of monkey mother surrogates boiled down to the basic components that a monkey infant would want warmth and nourishment in the form of radiant heat from a light bulb and a single teat for milk dispensing the first mother was a wire frame formed in a way to be adequate to provide postural support and nursing capability the second was made from a wooden block with a sponge rubber covering which was then itself wrapped in a tan coloured terry cough both were capable of providing milk and were warm the only difference was the comfort element of the mother's one being able to be cuddled up to and the other not both were designed with maintenance efficiency in mind thus only had one teat per monkey and were able to have their warming light bulb replaced easily with little interaction between the test subjects and the technicians for the initial experiment both surrogates were placed inside cages of eight newborn monkeys four had the cloth mother lactate and the wire one not and the other four had the opposite so the wire mother could lactate and the cloth one could not initially during the first few days of the newborn's life they were hand reared until they're able to explore the surrogates for milk after which for a few more days supplementary hand feeding was done until the newborn could fully feed off the surrogate for the first 14 days of life the cage floor was warmed and had a cloth lining on the 15th day the comfort flooring was removed and the proper experiment began with the amount of time on each mother recorded the monkeys were free to go to either mother if they so chose with the lactating cloth mother unsurprisingly spent most of the time on their surrogate using her as a source of affection and comfort what was interesting though was the group that had the lactating wire mother as the monkeys got older they spent less and less time on their feeding surrogate and instead went to the cloth mother for comfort during the experiment he was seen in the long term that the monkeys with the wire mother that could feed would increasingly spend more time up to 18 hours a day on their cloth surrogate spending on average under one hour per day on the one that could give them food this meant that the infant monkeys were preparing the contact comfort and perceived affection in all cases regardless of which one provided the milk the monkey would prefer the cloth mother for cuddling proving that at least in the study that the mother baby bond wasn't just created from nursing but instead the capability for love and that it overwhelmed any other variable another eight monkeys were used as controls for the experiment with each not having a choice of wire or cloth instead for having a lactating wire mother and the other four having a lactating cloth mother only both control groups were roughly the same weight by the end of the study meaning the wire monkey was said by harlow himself biologically adequate but psychologically inept but there is one difference and that was in their poo you see the control wire only mother group had softer stools hinting at psychosomatic issues harlow now sought out to test the bond between infants and surrogate by introducing the element of fear in all cases of dual surrogate the subjects preferred to go to the cloth mother when something scary happened what was interesting was after a little bit of time to cling on to their cloth mother the infants actually became confident enough to confront the scary object this wouldn't happen if they were clinging to the wire surrogate next came the open field test where each monkey was placed inside a six foot by six foot room with various items placed within it initially the room had various toys and interesting objects but no mother when confronted by the strange and scary environments the infant would curl up in a ball in a notable amount of distress when a wire mother was introduced no change was seen but when the cloth mother regardless if it had really infant was introduced the monkey would go to her for comfort and after a while would then have the confidence to explore even if an obstacle was placed between the monkey and the cloth mother the infant would make a beeline for her a control group that had not had any contact with a cloth mother before was used in the open field test and the monkeys would be paralyzed with fear regardless of the presence of a surrogate but would eventually get some comfort from the cloth mother after several sessions in the test room the test developed further by placing the cloth mother behind a glass wall with a scary object in between again like before the infant that being raised with the surrogates would run to her Harlow then went to test how long the bond could last between surrogate and infant some of the monkeys were removed from their cloth mother after six months and placed in a cage of their own after another six months had passed the monkeys were around their first birthday they were placed inside the original dual surrogate cage and the infant would go straight to the cloth mother the same results were also shown in the open field test when a monkey would still run to its cloth mother for comfort in a scary and new environment this meant that the test subjects remembered the comfort that they got from their mother and reverted back to their pre-isolated state to further test the bond difference between control and surrogate monkey groups another machine was devised called the flight box the test rig had a scary object placed in one end behind a removable wall the monkey would be placed in the middle of the box with two passages in front of it one to a cloth mother and another to a hiding spot out of view from the fear stimulus the results were rather predictable when the scary object was revealed the surrogate raised subjects would seek comfort from their cloth mother whereas the control monkeys would run and hide down the other passage now the monkey mother experiments helped to prove the link between comfort and security and infants and how it was preferred over nourishment which feels today like an obvious statement but if it wasn't for the experiments like this then we would still have a slightly view towards child rearing the studies did have a dark side and that was the socially and emotionally deprived test subjects which by modern standards feels wrong just looking at the fear in the monkey's faces makes me sad as a parent I can see the sadness similar to a human child and it makes me want to go pick up the monkeys give them a cuddle and tell them everything is going to be okay the studies came under severe criticism at the time and in the eyes of history have not come off well one major mistake of the experiments was that the link in behavior between human babies and rhesus babies was a bit tenuous this was because although human infants grab to their primary caregivers they do not rely on contact comfort as much as a monkey does you see this in young children that are happy to play on their own and be pushed around in prams whereas monkey babies are transported by clinging on to their mothers relying more heavily on contact for survival there are many more variables which are not addressed in Harlow's work especially when it comes to human child caregiver bonds for example financial societal and cultural variables which some of these elements are not factors in the society of the rhesus monkey the social and maternal deprivation of the test subjects cause panic and anxiety disorders which further added to the suffering of the heavily social based rhesus monkeys when introduced to other monkeys that had a more maternal upbringing were socially stunted and showed signs of severe distress when in contact with their peers Harlow's studies and others like it are cited as being a fuel in part of the animal rights movement in the United States Harlow went on to continue to use rhesus monkeys in his studies which would go down a much darker path in the exploration of loneliness isolation and depression including a study apparatus called the pit of despair which is most probably going to be a subject for a future video where would you rate this experiment on my new epic scale let me know in the comments below this video is a plain difficult production all videos on the channel are creative commons attribution share alike licensed my difficult videos are produced by me john in a semi sunny southeast in corner of london uk help the channel grow by liking commenting and subscribing check out my twitter for all sorts of photos and odds and sods as well as hints on future videos i've got patreon and youtube membership as well if you fancy supporting the channel financially and all that's left to say is thank you for watching criticality accidents are a technician's worst nightmare although a rare occurrence they can and do happen and can result in severe radiological exposure and an expensive cleanup process an event would unfold in the russian federation in 1997 and would have some similarities to two of the most infamous criticality accidents those being the deaths linked to the demon core although not identical the accidental prompt criticality of some fissile material due to accidental dropping of a reflector does sound familiar to louis slotton's exposure the accident would result in a dead very experienced technician and a six and a half day excursion i'm going to rate this event here four on my painted plain difficult disaster scale this is due to the event being relatively localized and didn't result in significant contamination sarov is a city in nishne Novgorod oblast russia originally founded in 1691 but our story starts quite a while after that in 1946 the town became a closed city and it was removed from all unclassified maps the reason was well but it found itself the center of the soviet nuclear weapons industry the all union scientific research institute of experimental physics was set up in the town which was a nuclear weapons design facility the institute over the years had set up testing grounds and hundreds of experimental facilities leading it to become the country's largest research and development organization as a quick side note the city became twinned with lost animos in the early 90s post collapse of the ussr the nuclear center was still the heartbeat to the russian nuclear industry conducting experimental studies in the fields of physics radiobiology and the health effects of radiation set over 12 facilities one of the purpose built facilities was the critical assembly which was designed to be an experimental tool to study fission reactions relevant for design and development of power research and impulse reactors the assembly was placed on a cart on tracks inside a room surrounded by concrete walls with a separate control room there were also other rooms for storage and workshops and each room had air samplers and detectors for measuring gamma radiation the critical assembly was essentially a piece of fissile material surrounded by two reflectors although the actual implementation was a little more complicated the assembly had the ability to move the fissile material inside a half sphere reflector up and down through the use of hydraulic pressure towards or further away from a fixed upper half sphere reflector for the construction of the assembly our calculations are used to ensure the fissile material remains subcritical the construction process involves excessive layering of various materials including copper steel and uranium which are prepared in the form of sets of machined hemispherical shells of standard sizes which the technician can assemble into various configurations the process was broken into two parts first constructing the lower half of the critical assembly then the second top half the lower half of the research assembly is constructed on a table that can move vertically up and down using hydraulics but the first part the table had to be in the up position during construction of the assembly but the second part the lower assembly is lowered and the upper part is placed on a stand consisting of a ring where it can be positioned horizontally over the lower part of the system once the whole assembly is constructed the operator is then meant to go to the control room to undertake the experiment also I should say that during the construction process it's meant to be a two-person job the operator and a supervisor who should be double checking all of the work during the experiments the assembly was essentially a small fast reactor that can regulate itself in a rather clever way if the mathematics are correct then as the assembly heats up the materials expand reducing the effect of the reflectors and as it cools down the components return to their previous position the behavior is seen as sharp fluctuations of the measured neutron flux which stabilizes after several cycles after which the critical assembly operates at a constant level of neutron yield sensors placed inside the assembly room tell the operators the state of the materials which allows them to move up and down the lowest sphere to change the power levels if the assembly went out of control it would melt thus ending the chain reaction and was an important safety feature all experiments using the assembly were strictly controlled by a regulatory and technical framework set out by the russian federation ministry for atomic energy the procedures precisely outlined the management requirements for work with critical assemblies they require that this type of work be conducted only by a group of trained technicians with each person being responsible for strictly defined actions within a sequence of operations which are closely supervised obviously this is important as a mistake can result in a criticality event which you know is not great but we can probably predict what is going to happen next roll on the morning of the 17th of june 1997 a 41 year old male named alexander zhakarov set to recreate a 1972 experiment using uranium with a copper reflector assembly a technician was a very experienced worker with several hundred experiments under his belt he was familiar with the process for the particular assembly but contrary to the rules he was working alone in the hall zhakarov had also broken another rule and that was by not properly filling out the appropriate paperwork for the experiment he had taken the dimensions for all of the components from the original 1972 log book but he had mistakenly written down the wrong outside diameter instead of 205 millimeters he noted 265 millimeters at 10 50 a.m whilst placing the upper reflector on its stand above the fissile material it slipped from the technician's rubber-gloved hand and fell onto the lower part of the assembly this sent the subcritical assembly prompt critical and a blue flash of light and a heat wave was experienced the lower part of the assembly was ejected downwards into the bottom of the stand knowing his mistake zhakarov fled the room and reported to his superiors explaining the situation he claimed to have received more than a fatal dose initially he was conscious but within minutes his exposure began to take its effect the radiation protection personnel performed an initial radiological survey of the technician this detected the neutron induced gamma radiation emitted by radionucliides in his body it was estimated that he had received a whole body dose of 10 gray for comparison between four and six gray whole body dose has been lethal before zhakarov was sent to hospital for treatment arriving at sarov occupational medical service at 11 45 in the morning on the 17th of june by this time he was experiencing nausea and he began to vomit increasing in frequency over the following two hours the sickness was lessened by 2 p.m. by antibiotic drugs the situation was looking pretty dire as his condition deteriorated it was decided in the evening that he be transferred for specialist care in moscow he was admitted to the clinical department of the institute of biophysics in the ministry of health at 9 p.m. he was fully conscious but his fatigue and headache were persistent his hands showed signs of severe exposure they would become severely swollen during the first night between the 17th and the 18th of june on the morning of the 18th of june the patient's general state was evaluated as critical and getting worse by the hour his hand injuries continued to worsen with the spreading of the swelling over more areas of the forearms on the 19th of june the condition of zhakarov was dire by 2 p.m x-rays showed fluid on the lungs and his arms were deteriorating rapidly later on in the day the decision to amputate both arms was taken and the surgery was performed around 4 p.m. initially his condition was stable but sadly not for long at 2 45 in the morning of the 20th of june 1997 his blood pressure dropped dramatically and at 3 20 in the morning around 66 hours after exposure the patient died but what happened to the critical assembly after zhakarov left the room and was taken to hospital as the technician passed away in the early hours of the 20th of june the chain reaction would still be ongoing back to 10 50 in the morning on the 17th of june the specialists arriving at the accident facility had to determine the status of the critical assembly and the possible consequences of the accident at 11 a.m evacuation of all staff from the building where the accident had occurred and the radiation survey outside the building was carried out by the early afternoon it was confirmed that there was no airborne or surface contamination but the assembly was still emitting significant neutron and gamma radiation which would preclude anyone from entering the room all but the dosimeter furthest away from the experiment showed readings off the scale another meter was entered into the room and showed the neutron flux was stable hinting at the chain reaction being self-regulating obviously the chain reaction had to be stopped and this necessitated altering the assembly remotely the first step taken was to remove containers of nuclear materials which had not been used in the construction of the assembly this was conducted by using a robot once complete the same robot was used to alter the assembly at 12 45 in the morning of the 24th of june 1997 when a vacuum gripper was used to remove most of the assembly from the sand leaving only the outermost lower copper hemicell in place the remainder of the assembly was disassembled bringing an end to the incident due to the excursion the radiation monitors in other rooms of the facility showed normal levels but the technicians personal dosimeter read a neutron exposure of 45 gray and a gamma dose of 3.5 gray it was thought that the uranium had reached temperatures of up to 865 degree centigrade during the excursion because the accident was solely down to zhakarov and his infringement of the rules set out by the facility although his death is a tragic accident some comfort can be taken of that no one else received elevated radiation doses although the IAA found the rules of the facility to be adequate they still did not prevent the accident after the accident experiments with the test rig were stopped to implement safety upgrades to the research operations this is a plain difficult production all videos on the channel are creative commons attribution share alike licensed playing difficult videos are produced by me john in a not so sunny southeastern corner of london uk help the channel grow by liking commenting and subscribing check out my twitter for all sorts of photos and odds and sods as well as hints on future videos i've got patreon and youtube membership as well so you can check them out if you fancy supporting the channel financially and always have to say yes thank you for watching phobias are a fascinating part of the psyche some are completely understandable and possibly even evolutionary as being scared of dangerous things and creatures is pretty beneficial for survival but a question has eluded psychologists how are phobias present in some people but not others and can you condition a fear in a human test subject this question would lead psychologist john b watson and his assistant graduate student rozzolene reyna down a very ethically questionable path not only was experimenting on a human controversial but the test subject would be a nine month old baby today we're looking at the controversial heartbreaking and morally questionable baby albert experiments welcome to the dark side of science nothing about the statement experimenting on a nine month old baby sounds good and the idea to deliberately scare an infant is very off-putting the experiment is even more controversial than the monkey mother studies as the long-term effects could be scarring for an otherwise healthy human child as such i'm going to rate the experiment here eight on my ethical scale as a subject had no say in becoming part of the study and to the alleged sourcing of the child was not shall we say in the most praiseworthy way but before we get to baby albert we need a little background to the person behind the experiment john b watson john broadus watson was born in travellers rest south carolina on the ninth of january 1878 he was brought up in a strict christian family but things would change in a teenager's home life when his alcoholic father left the family this would cause john to become apathetic towards religion the family later moved to greenville south carolina where watson would get a chance to meet people of different backgrounds igniting his interest into psychology his secondary education was marred with run-ins with the law for fighting and bizarrely discharging a firearm within city limits however he was still able to gain a place at greenville's firman university at the age of 16 his time at university was difficult having to work several jobs he didn't excel and did not create many social bonds which left people to think of him as lazy and antisocial but he persisted and at the age of 21 gained a master's degree he managed to get into chicago university a couple of years later and finally his career started to take a more positive turn studying under some notable professors including jong dui and james roland angel watson began to develop an interest in behavioralism during his time at chicago he read up on the work of ivan pavlov known for his classic conditioning a discipline which would directly influence watson's later experiments as a side note this is the same pavlov with the dribbling dog i should say that during this time watson had got married and was the father of two children but his marriage would break down but this will come a bit later on in our story in 1902 watson gained his phd whilst working as a research professor at the university of chicago in 1908 watson accepted a faculty position at john hopkins university being promoted to chair of the psychology department not long after starting he continued to study behavioralism releasing a paper in 1913 named psychology as the behaviorists views it a manifesto of sorts laying out the goals of the new discipline behaviorism as watson saw it sought to understand behavior by only measuring observable behaviors and events and that these actions were influenced from external stimuli as a consequence of that individual's history and learned behavior from reinforcement punishment this new form of psychological study wasn't initially accepted by the wider scientific community but gradually the new discipline would make inroads to be a recognized field the discipline would be expanded upon by scientists like bf skinner aka the guy who made a pigeon guided bomb which i made a video about a long time ago check it out if you want to see a even worse produced plain difficult video in 1915 watson served as the president of the american psychological association watson would continue to produce papers expanding on his views into behaviorism which would reject the study of consciousness with his important later career 1924 book behavioralism but before that we need to look at a couple of very turbulent years for watson which brought about the baby albert experiment in 1919 watson released a paper called a schematic outline of the emotions during this study he observed a number of infants which revealed three fundamental motions fear rage and love each caused by a set of conditions watson used various animals to observe the reaction from the test subjects in most cases especially when introduced to dogs and cats the infant showed a neutral or an inquisitive reaction but when introduced to a pigeon flapping its wings most subjects showed surprise or even fear of the motion and sound to induce fear some of the test subjects were placed in a dark room or in a room on their own needless to say the children became distressed now these tests are pretty mild and generally yielded predictable results but what if you can get an infant to fear something that had initially yielded a neutral response for example one of the cuddly animals from his 1919 study this would be done by introducing a neutral stimulus like a rabbit with a scary stimulus for example from a loud banging sound they tried to answer the following questions that if a fear stimulus could be transferred to other animals or other inanimate objects once a fear of being conditioned to in the test subject they also went to find out for how long right this is where the study in my opinion crosses the line as the sourcing of the test subject and finding a parent willing to allow their child to be given a phobia would be understandably difficult baby albert was a child of a wet nurse at the harriet lane home a pediatric facility on the john hopkins campus now it's not 100 known how albert was found clearly a major contributory factor was the convenience as harriet lane was adjacent to the fifth clinic where watson's infant laboratory was housed there are three possible ways watson got hold of albert that have been considered the first is for a paid study the second is by using his connections at the hospital to coerce and allow access to the infant and the final is from doing the experiment without the mother's knowledge but we will never know a hundred percent how albert was found by watson and we don't even know if that is his real name what we do know is that he was selected due to being healthy unemotional child who rarely cried the experiment wasn't just conducted by watson alone but also one of his graduate students rosaline reyna i should say that his relationship with her had caused issues with his breaking down marriage by late 1919 at the start of 1920 and at eight months and 26 days of age baby albert was entered into the study albert was observed reacting to a number of live animals for example a rat a dog a rabbit and a monkey and various inanimate objects including human masks cotton and a burning newspaper during the initial phase albert showed no elevated signs of distress or major reaction to the stimuli what watson and rosaline did see was elevated distress when a metal bar was hit with a hammer which created a large amount of noise sending little albert into a burst of tears two months would go by after albert's baseline observations before the experimental conditioning would begin watson and reyna attempted to condition him to fear one of the items that had previously garnered a neutral response a white rat was chosen to be an item to condition albert's fear response this was done by presenting the animal to the infant and every time he touched it the metal pole was hit with the hammer creating the scary noise it wouldn't take long for albert to start to fear the cuddly animal after seven pairings of the rat and the noise in two sessions one week apart albert reacted with crying when the rat was presented subsequently with no loud noise although he didn't seem as distressed when he was allowed to suck his thumb which hints at a phobia not actually being created a couple of weeks after the conditioning albert started to fear other similar items that shared similar characteristics with the rat the generalized fear manifested whenever the family dog a fur coat some cotton wool and even a father christmas mask was presented to the infant a couple of weeks after that albert's fear of the rat had died down including the response to the other similar items this prompted watson to recondition the infant by presenting the rat again with the loud noise each reconditioning would only take a few rounds of the scary noises but what are the questions set out by the pair before the experiment how long does the condition last 31 days after no exposure to the test items albert was shown a rat a coat and santa mask he again showed a fear response not long after the final experiment albert's mother withdrew her child from the study and left the hospital for good leaving little trace of what happened to the test subject this had two downsides the first was that albert was unable to be reconditioned to not fear the rat and the linked fear producing things and the other issue was that the study was incomplete right well taking into account that the experiment happened over 100 years ago we do have to look at it in the context of the time when experimental psychology was in its infant hood and the study was even one of the first to be filmed at a great cost to the university by today's standards the experiment was morally ethically and even scientifically on shaky ground the first two reasons are pretty obvious as well experimenting on children is just wrong at least in my eyes but the scientific failures are very important to consider the study did not have a control subject involving only one infant which makes the data hard to properly interpret as one result does not make a conclusion it's almost impossible to know longer-term effects on baby albert as we may never know if the phobias if any created during the experiment were long-lasting we will never know for sure what happened to albert or even if it was his real identity researchers into the experiment have a couple of potential identities with one dying at the age of six and another living until 2007 but we will never know for sure some doubts present as to whether or not the conditioned fear response was actually a phobia this was due to a reduced response when the infant was allowed to suck his thumb which almost made him be able to ignore the loud sound the experiment was responsible in part for destroying Watson's working career but not how you might think what came out later in 1920 was that the psychologist was having an affair with his assistant Rosalind Rayner the scandal would result in Watson's dismissal from his job at john hopkins university the affair became front page news during the divorce proceedings in the Baltimore newspapers destroying the psychologist's reputation and with it his university career not that that was the complete end for him as he released his behaviorism book in 1924 and also psychological care of infant and child in 1928 he would have another two children and would work for an advertising company from late 1920 he would raise both children to his and Rosalind's behaviorist principles and sadly both sons would attempt suicide with one of them being successful in 1954 Rayner died on the 18th of June 1935 in Norfolk Hospital in Connecticut she had unexpectedly contracted dysentery from eating tainted fruit Watson would never remarry and pass away himself in 1958 at the age of 80 this is a playful production all videos on the channel are creative commons attribution share alike licensed playing difficult videos are produced by me john in a kind of sunny southeastern corner of london uk help the channel grow by liking commenting and subscribing check out my twitter for all sorts of photos and odds and sods as well as hints on future videos i've got patreon and youtube membership if you fancy supporting the channel financially and always have to say yes thank you for watching damn failures are catastrophic events the sheer magnitude of the destruction they reap is unimaginable one such disaster in 1963 caught live on tv would show the world the potential havoc that can be inflicted on a community a failure to recognize the risks of poor site selection would show that the los angeles department of water and power had not learned the lessons from the st francis dam nearly 30 years earlier the event did however show the benefits of regular inspections as even though failure would destroy hundreds of homes and run into the costs of millions the death toll was a relatively modest five it was saying that the Baldwin Hills dam failure was assured when the project was green lit but heroic actions on the day limited the potential for tragedy as such i'm going to rate it here four on my disaster scale but here on the legacy scale as it was one of the first dam failures caught on live tv welcome to a brief history of the Baldwin Hills dam and reservoir failure our story starts just before the second world war and the plan to build a reservoir to supply the south la neighborhood of Baldwin Hills with safe and reliable drinking water la throughout its life has been plagued by droughts which was the original reason for the la aqueduct system and the ill-fated st francis dam as the city expanded into different suburbs naturally in a need for basic amenities such as electricity roads and of course water arose the project started to undertake surveys of a proposed site in 1939 it wouldn't get underway until the mid 1940s the site selected was atop one of the tallest hills in the region in the Baldwin Hills area this was to make use of an already existing ravine but this convenient location came at a big cost this was that the location for the new reservoir was above the englewood fault line and the site area itself was formed at the subsurface of loose sandy soil the engineers were aware of the associated challenges of building on such an area and set out to design the project to be resistant to erosion and seismic activity the reservoir was going to be a relatively small in compared to some other projects undertaken by the los angeles department of water and power only impounding around 900 acre feet of water at an average depth of 65 feet the comparison the st francis dam was intended to hold back 38,000 acre feet and whilst we're on the subject both projects had something else in common well apart from catastrophic failure and that was designers long gone were the days of moholland but the lead in the Baldwin Hills project was Ralph Proctor towards the end of his career but at the beginning he had worked under the former civil engineer during the st francis dam designing construction Proctor had become over the following decades post st francis failure an authority on new methods of control soil compacting in doing so becoming the person responsible for design construction and maintenance of all dams in the los angeles water system the designer the reservoir made use of a steep ravine by excavation at the abutments and filling in the eroded valleys the reservoir was to be held back on three sides by compacted earth dikes with the Baldwin Hills dam on the northern face creating a roughly square shape and all of the structure was going to be earthen the main consideration for the engineers was preventing water seepage which is one of the main risks to an earthen dam as this can cause erosion and ultimately total failure like what would happen to titan in the 1970s to prevent this the los angeles department of water and power devised a lining around the reservoir basin to stop seepage into the dam's foundations the lining consisted of a 10 foot thick line of compacted clay tapering down to five feet at the top of the embankments this was placed on a quarter inch asphalt membrane which itself was sprayed onto the subgrade soils in two coats between the clay lining and the asphalt membrane a cemented pea gravel drain was constructed to collect any seepage sending it to a central observation and measuring station called for drainage inspection chamber on top of all of this another asphalt coating was applied a separate foundation drainage system was also provided and additional tile drains at the toes of the reservoir slopes and a special fault drain was installed and fed directly into the drainage inspection chamber all these drains allowed effective monitoring of the structure for any seepage the design relied heavily on the clay lining to prevent seepage and if any would occur the technicians on the project could observe the amount easily if any cracks occurred in the clay it was thought that the asphalt membrane would still hold out any significant erosion with the ability to properly monitor seepage it was thought that ample time would be available to drain the reservoir and undertake repairs destruction began in 1947 and in 1949 an inactive fault was discovered necessitating the modification of the positioning of the gate tower worries were raised during the design and construction of the project on the suitability of the structure and its location the concern emerged from the active fault line and unsuitable foundational material lead engineer Ralph Proctor not the type of man to accept criticism proceeded with the project according to his own design construction was completed in 1951 by this time the Baldwin Hills dam reached a height of 232 feet and stretched a total of 650 feet in length as a result of the design considerations of the reservoir after filling in 1951 the dam and embankments were frequently inspected and monitored all would seem well for around 12 or so years until one such routine inspection revealed something worrying around 11 15 a.m the reservoir's caretaker noticed that brown water had begun draining from the pipes underneath the asphalt membrane liner this hinted that water was seeping towards the foundations at 11 30 a.m he figured out that the northeast and southeast tow drains and the fault drain were discharging muddy water in the inspection chamber which as we've seen in disasters before that dirty water means erosion shortly after the alarm was raised and by 12 20 p.m the outlet works were engaged to empty the reservoir but this would take at least 24 hours because of this the los angeles department of water and power contacted the police to evacuate downstream from the reservoir around 1600 residents would be successfully evacuated all whilst workers above them frantically attempted to show up the failing dam and clear out the emergency discharge pipes at 2 20 p.m lowering of the reservoir water level revealed a three foot wide break in the reservoirs in aligning an attempt was made to try and plug the hole with sandbags but this proved ineffective the efforts would be in vain as at 15 38 the Baldwin Hills Dam failed releasing some 250 million us gallons of stored water down onto the residential buildings below interestingly the breach was captured by ktla using a helicopter the footage dramatically illustrated the pure power of the tidal wave of destruction the well timed and shot failure is something we take for granted today with 24 hour coverage but for 1963 this was rather unique within an hour and a half it was all over the reservoir was now virtually empty five lives were lost and millions of dollars of damage was inflicted although tragic the disaster was a testament to the quick response of the caretaker operating engineer lad wp and evacuation personnel with so much destruction the next question that had to be asked was how did the dam that had worked and been monitored for 12 years fail so quickly and dramatically needless to say the failure sprouted several investigations and has been a key learning point for the dam engineering industry the extensive drainage system wasn't as perfect as originally it seemed because of calcium carbonate deposits developing necessitating frequent cleaning and maintenance this caused a reduced amount of seepage to enter the inspection chamber leading to ineffective measurement of potentially eroding water throughout its operating history the reservoir was emptied a couple of times due to cracks in the clay and asphalt and leading up to 1963 the flows from discharging horizontal drains under the main dam varied rapidly after the reservoir was fully drained the damage to the asphalt paving clay cap and membrane could be fully seen there were significant cracks which allowed water to erode away at the foundations of the dam the damage to the lining has been theorized to have been caused by a number of factors either on their own or combined during construction heavy machinery was allowed to travel over the fragile asphalt causing hairline cracks in the surface and emptying and filling a reservoir could have caused stress fractures and effects due to nearby oil filled repressurization another factor could have been from tectonic movement from the nearby Inglewood fault line that had weakened the structure and lining it was found that during oil drilling works to the south of the dam that drilling fluids were lost in the upper several hundred feet hinting at cavities and fractures in the foundation rock it could be taken that this was similar underneath the reservoir as well it is thought that the lining and membrane had been ruptured throughout its life allowing seepage into the unknown cavities underneath the dam as well as the known inactive fault lines the resulting erosion reached a tipping point which could have been the cause of the total structural failure the cause of the failure was and still remains a case open for study in the early 1970s discovery of faulting and surface seepage of oil filled waste brines along the fault near the south of reservoir showed that oil filled injection of waste disposal and improved recovery of oil could have been a significant cause of the failure this triggered hydraulic fracturing aggravating movements on the fault traversing the reservoir on the day of the failure the reservoir was never refilled and is now part of the community park because of the disaster it's thought to be around 12 million dollars but luckily it wasn't higher due to the actions of everybody on that December day this is a plain difficult production all videos on the channel are creative commons attribution share alike licensed plain difficult videos are produced by me john in a at the moment sunny southeastern corner of london uk help the channel grow by liking commenting and subscribing check out my twitter for all sorts of photos and onto and sods as well as hints on future videos i've got patreon and youtube membership as well so if you fancy supporting the channel financially you can check them out and all that's left to say is thank you for watching history is doomed to repeat itself and today's subject is no different lost sources as we've seen in the likes of maya puri and goyanya are easily mistaken for scrap material leading to accidental exposure to workers the case would be similar in istanbul turkey in 1998 i'm going to rate this here five on the painted plain difficult disaster scale and here two on the historical legacy scale as i don't know about you but i hadn't actually heard of the event until one day when i was browsing the iaea publications list this video as such is unsurprisingly going to follow the iaea report rather closely if you want more detail then feel free to check it out and the link is in the description cobalt 60 tether therapy units can play a vital role in the treatment of cancer however the radioisotope has a relatively short half-life of just over five years this means that a tether therapy machine needs its cobalt source to be replaced every once in a while as its beam of penetrating gamma radiation deteriorates and as such an industry in replacement and maintenance is created turkey was no exception for this and as such multiple specialist companies operated swapping radioactive sources and maintaining tether therapy equipment during the 1990s around 40 or so radio therapy centers existed in turkey all of which needed maintenance and source replacements at one time or another one such company operated in ankara and would cause contamination in istanbul due to storage of three such used cobalt sources the company was licensed by the turkish atomic energy authority or taik to import transport and re-export radioactive sources which was required by law but before we go into the timeline of events let's look at the cobalt source and what it does cobalt 60 tether therapy units are manufactured with sources containing a high activity level of around 185 terebecuels this is to help keep the unit in action for as long as possible whilst also not having excessively long treatment times as mentioned earlier cobalt has a half-life of just over five years and because of this the tether therapy machine will eventually take excessively long periods of time to treat the patient this necessitates the removal and replacement of the source but it's not like you can just pull it out and chuck it in the bin like a battery playing difficult does not condone throwing batteries in general waste please dispose of responsibly you see even though it's no longer ideal for a tether therapy machine the source can still be very deadly with an activity around three terebecuels but sometimes this number can be much higher if the machine itself has failed or has been decommissioned the radioactive material was in the form of cobalt 60 grains contained inside an international standard capsule to undertake a swap over of sources an exchange container was employed it was designed to be connected to the tether therapy head for shielded replacement the container had a cylinder for removal and installation of sources it had a retractable drawer that allowed two sources to be temporarily held within this was to allow the spent source to be removed via the cylinder while still shielding the operator from the new and old cobalt once the old source was removed the draw could be closed allowing the new source to be installed into the tether therapy head the exchanger couldn't be closed with the two sources inside meaning it was only designed to transport one item after completion of the exchange the cylinder and draw assembly are secured and a steel cover plate is bolted on the transport the cover plates were fitted with wire seals and the whole exchange container is then packed inside a transport package which consists of an inner wooden crate and an outer metal case this brings us on to the 27th of December 1993 and one of the many specialist tether therapy maintenance companies applying for a license from tec to export free use cobalt sources to the usa for disposal the three containers had an officially claimed activity of 6.4 46 and 41.8 terebeckles respectively there are packaged inside source exchanges which were in turn within their transport packages on the 6th of May 1994 permission was granted after radiation measurements were taken by officials istanbul harbour's customs directorate was informed on the 12th of May 1994 but export permission had been granted what was strange was that the export didn't go ahead and the sources were stored in anchora at the company's storage site the state licensing authority tec was not informed meaning the storage was not known of not much else was happened to the sources until february 1998 when the company shipped two of the three to their site in istanbul upon reaching their destination the company planned to store them in a general warehouse the total claimed activity of the two containers was 52.4 terebeckles after some time space became available in the warehouse and the packages were moved to empty premises adjoining the warehouse what is bizarre is that this was a shop and had no windows and only metal shutters and the door was unsecured the storage location was in cuckoo check majay district of istanbul this was obviously a very good and safe decision but unlike many other stories i've covered like this the sources were not stolen but instead were just left in a shop when it was sold on to new customers on the 8th of december 1998 the packages were sold by the new owners of the warehouse for roughly 30 dollars a scrap metal to two brothers who lived in the same district they took the scrap aka radioactive sources home for dismantling a couple of days later the items were moved from the house to one of the brother's father-in-law's houses where an open area yard was opposite it was there that the dismantling of the exchange containers took place one of which had their drawer removed and one of the three men reached their hand inside to have a feel during this dangerous operation passes by looked on both sources and the exchange containers were then transported back to the original house where they were placed in the yard next door used for scrap metal storage at about 9 a.m on the 13th of december 1998 the dismantling continued removal of the brass collars at the top of units became an issue which was resolved by cutting with an acetylene torch revealing lead parts of the shielding the containers were rolled over and at this time one of the sources was thought to have exited their exchange containers whilst all this was happening again passes by watched on on the same day the first signs of radiation exposure were experienced by the three men with the usual symptoms of vomiting and nausea by the evening many of the onlookers in the scrapyard also began to feel unwell the first of the affected went to a local health clinic where they were treated for suspected food poisoning this seemed to help but they were discharged to get better at home on the 17th of december the man who put their hand inside the exchange unit started to experience reddening on the tips of his two fingers not a good sign parts of the lead shielding and parts the exchange units were sent to a scrap metal smelting facility this happened when the owners who were seeking medical care were away from the yard luckily one of the sources in the drawer did not get smelted and stayed on site however anything else got turned into recycled material two of the people started to feel the effects of radiation sickness went to a larger hospital to seek medical attention luckily after some questioning from a doctor ars was finally suspected on the 8th of january 1999 by the afternoon blood tests for the two and six others were arranged the authorities were informed and at 3 p.m initial surveys were conducted at the scrapyard's entrance and they detected something by 4 30 p.m the yard was evacuated and the area around the yard was also called and off to allow authorities to plan what to do next one of the cylindrical drawer assemblies from one of the exchange containers was seen on the ground in the scrapyard to collect the source a shielded container was made from lead bricks inside a steel container and placed on the bed of a truck and a grab truck was used to pick up the material as a credit to the operators the item was collected on the first attempt however dose rate surveys showed that there was more in the yard surveys showed high levels of activity under a pile of scrap metal a mechanical grab was also used to slowly tackle the pile but after each removal the rate increased this was due to the surrounding scrap acting as a radiation shield and thus the more you remove the more radiation gets out a new shielded container was fabricated and mounted on the back of a truck and another truck was used with a long boom arm with a dosimeter attached to the end of it 10 teams of two were set up to recover the scrap for limited periods of time to reduce exposure an individual dose constraint of two millisieverts was set with the grab drivers limited to one millisievert each team was only to have one go meaning 10 attempts to find the source at the end of the run not all had been removed another attempt per team was needed and after reviewing doses another attempt could go ahead and after another four goes the source was found and safely placed inside the storage container out of the recovery team an average of 1.15 millisieverts was experienced with the highest dose of 5.47 millisieverts with the next highest at 2.05 the highest dose was a senior member of the health physics team who undertook the initial dose survey surveys of the scrap yard showed no more activity meaning it was now clear in total only one of the sources was actually found with an activity of 3.3 terebecules but what was strange was where was the other source scarily this was never found searches at the smelting factory and iron or wire produced from the scrap metal show no activity essentially the cobalt 60 from the second exchanger had vanished into thin air or more likely it was never actually put into the carrier the serial numbers of the sources were destined to be deported back to America did not match the numbers on the company records so who knows when a missing source went on Tuesday the 12th of January 1999 the Turkish authority sent an official request for medical assistance from the IAEA the next day the evaluation of the 15 patients IAEA experts was completed and a report was sent to take ten of which were exposed for a significant amount of time between two and six hours the patients one to five the estimated doses were around three gray each with patient six estimated at two gray while all the other persons for whom analysises were undertaken estimated doses were below one gray the comparison a whole dose of three gray can cause death although people have survived higher let's look at the medical aspects of the event at the beginning of hospital treatment on the 12th of January 1999 patients one to five showed life-threatening conditions necessitating immediate blood transfusions they were given bone marrow biopsies showing hyposellular bone marrow but within a week of treatment improvements were observed while white blood cells going back to normal levels three of the original 10 were discharged on the 25th of January 1999 by the 24th of February 1999 all other patients were discharged after a successful treatment of antibacterial antiviral and antifungal drugs the patients were monitored regularly throughout the year with patients one to five having to take caution due to increased risk of infection remember the guy who put his hand inside the container to see what was inside this would prove to have been a big mistake as in April 1999 an x-ray examination of the right hand showed a slightly thinner bone tip it was decided in July to amputate the tip of his finger but as always this was followed by an ulceration and necrosis requiring further treatment the event caused much distress to the public with it being rather unfairly compared to Chernobyl the orphaned source event altered the public psyche leading to greater fears of radiological incidents but did have a positive in raising awareness of the risks of improper handling of material at the time of the event the Turkish authorities did have emergency plans for radioactive contamination from outside of its borders for example from a nuclear reactor failure but it didn't have a plan for an incident within the country although the orphaned source proved to be dangerous to the affected persons it could have been much worse if the cobalt 16 made its way to the foundry as well that could have made a much bigger mess thanks for watching I hope you enjoyed the video this is a plain difficult production all videos on the channel are creative commons attribution share alike licensed plain difficult videos are produced by me john in a currently sunny southeastern corner of london uk help the channel grow by liking commenting and subscribing check out my twitter for all sorts of photos nods and sods as well as hints on future videos i've got patreon and youtube membership as well so if you fancy check them out and all that's left to say is thank you for watching industrial catastrophes are not very frequent events but are more common than many would like and every decade has had a multitude of shocking disasters the 1980s was no exception and definitely had more than its fair share like for example the well-known ones in the form of Chernobyl piper alpha and bullpile to name a few these are the ones that are so devastating that the ramifications of such events have traveled well beyond the borders of the country of origin but what i personally find more worrying are the smaller localized events the ones that are not often reported across the globe getting forgotten to time these disasters are the ones caused by seemingly mundane reasons such as incorrect routine maintenance on the face of it minor adjustments to procedures or just a failure to check things properly an explosion in a chemical facility can easily become part of the white noise background of the daily news cycle and in some regards allows the event to be downplayed a disaster would rack up a death toll of 23 employees injuring 314 and the company in charge would get a modest five million dollar fine even though safety on the site was inadequately managed as such today's subject will get a rating of seven on my plainly difficult disaster scale and also a seven on historical legacy scale as the event helped improve process safety welcome to a brief history of the 1989 philips petroleum chemical plant explosion and fire in pasadena texas philips petroleum was a petrochemical company with its history tracing all the way back to 1917 the deforming of the company by brothers lee eldest philips and frank philips based out of oklahoma quickly the company worked in all parts of the oil industry including fuel production crude oil pipelines refineries and marketing of petroleum products like many companies during this period the demand for fuel boosted the organization's coffers but the growth would really speed up during the big old dumpster fire that was the second world war by the late 1940s the ever-growing philips petroleum had become active in the chemicals business creating philips chemical company which set up and began operating a large plant on the houston ship channel in the 1950s the plant began producing polyethylene plastic trademarked as marlex this was used in blow molded and rotationally molded components this would be the facility that we will be focusing on today and would be the epicenter for a disaster nearly 40 years after it began operation but in 1980s the site was being used to produce polyethylene which is one of the most common plastics used in bags food packaging and pretty much anything you use day to day making this material can be a dangerous process as highly flammable gases are given off which would be the cause for the disaster but first let's look at the process used by philips chemical high density polyethylene is manufactured at plants 4 and 5 at the houston chemical complex at high temperatures and high pressures the process uses a thing called a loop reactor which is an arrangement of 30 inch diameter pipes mounted vertically in 150 feet tall continuous circular shaped structures this heats and pressurizes the chemical mixture to 600 psi and to a temperature range of 82 to 110 degrees centigrade reaction is one of condensed polymerization of around 95 percent ethylene dissolved in isobutane hydrogen and hexene were also added to achieve targeted product quality specifications as a reaction product gained mass in the loop reactor it would eventually become heavy enough to drop out of the circulating reaction mixture at the bottom of the loop reactor were setting legs 6 in total and 8 feet long but are used for collecting the polyethylene particles each leg had two valves one at the top and one at the bottom the upper consisted of an air operated 8 inch ball these were used to isolate the section from the reactor after production the bottom valves would take off ones that were fed into a flash tank once a leg was full or clogged with product the 8 inch ball valve would be closed this was to stop the highly bamboo gases inside the reactor from venting to atmosphere the setting legs were the interface between the high pressure reactor and low pressure flash tank process sections once the process was complete the polyethylene fluff was then taken from the tank to be turned into the finished product but the way the reactor and setting legs were designed to work had a problem and that was everything had to be shut down once all six became full or clogged this necessitated the need to be able to empty the legs during full power production to reduce downtime but its petroleum had a policy for safe equipment isolation meaning any maintenance would have backup isolation called double blocking this can be done by a double valve setup obviously this would only work if the area want to isolate had two valves if this wasn't possible then a bolted flange setup could be used to have two sets of protection this had in the case of loop reactor a problem that installing the blind flange was time consuming making maintenance whilst the reactor was running pointless so as we see very often in these videos a local solution was devised this involved the eight inch ball valve being closed to isolate the plug setting leg from the loop reactor then the eight inch ball valve stem was physically locked in its closed position finally the inlet and outlet air hoses actuating the eight inch ball valves from the remote valve switch control panel this was double locked but definitely not double blocked as any failure of the ball valve could mean the reactor was exposed after this locking was complete the setting leg could be emptied by removing the release valve and having a contractor reach their arm up into the leg to put out the fluff this leads us to the 22nd of October 1989 three of the six setting legs in reactor six in plant five were plugged as had been done before during production operations personnel isolated the setting legs according to the alternative isolation procedure closing the eight inch ball valve locking them and disconnecting the air hoses the first was disassembled and had its fluff removed relatively easily by the contractor this happened whilst the reactor was still in operation the crew wouldn't tackle the second leg until the next day when the contractor attempted to remove the blocked fluff only three quarters was set free leaving the leg partially blocked the morning hadn't gone to plan but the contractor attempted to get out the remaining material around lunchtime at some point the air hoses to the valve had been reconnected and lockout device was not properly installed somehow the valve opened releasing the highly flammable gases out of the reactor into the air at around 1 p.m the reactor lost its entire contents of around 85 000 pounds of the heavily flammable process materials after which the escaping chemicals then ignited the explosion created a force equivalent to 2.4 tons of tnt registering as a 3.5 magnitude earthquake on the Richter scale several other explosions were felt as chemical stored on site also ignited 23 people were killed and 314 were injured the fire raged at the 14 story high site first response was provided by philips petroleum company's contractor fire brigade which was soon joined by members of the channel industries mutual aid association calling water from the fire apparatus was trained on the area of the fires but the intensity and the fuel load was such that the responders were only able to contain the fire the efforts were also hindered by low water pressure caused by pipe rupturing during the explosion eventually control over the fire was achieved by approximately 1900 hours although smaller blazes continued throughout the night rescue and recovery of the victims from the explosion was severely hindered during the fire and even afterwards due to fears of structural collapse a one mile no fly zone was set up around the site to prevent anything being disturbed by aircraft downwash with a heavily damaged site reaching a cost to be reported over 700 million dollars a question is left how well investigators quickly found that the valve had been improperly locked out but a lot of guesswork is left as to why this is because the operators working at the reactor were killed in the explosion it shouldn't have really happened as a process for locking the valve was very well known and established on site investigators also discovered that the valve was capable of being locked closed as well as worryingly open which could have led to confusion coupled with the operators not removing the airlines could have been the root cause regardless the procedure should never have been allowed to happen without a blind flange which would have been the form of double protection and this was reflected in the investigation into the disaster which found that Phillips petroleum had a lack of process hazard analysis employing inadequate standard operating procedures the legs came into question for not having a failsafe block valve and an inadequate lockout tag procedure in the form of double locked but not double blocked procedure furthermore there was an onsite lack of combustible gas detection and alarm system which didn't give workers warning of an impending incident also it was found that the fire wasn't helped by the presence of ignition sources and inadequate ventilation systems for nearby buildings Phillips was fined four million dollars for the infractions that led to the explosion as well as improving working practices across the company and its sister enterprises the ramifications from the event would spread widely across the whole industry helping improve safety although things are never as safe as they should be this is a plain difficult production all videos on the channel are creative commons attribution share alike licensed plain difficult videos are produced by me john in a currently sunny southeast in corner of london uk help the channel grow by liking commenting and subscribing check out my twitter for all sorts of photos and odds of sods as well as hints on future videos i've got patreon and youtube membership as well so check them out if you fancy supporting the channel financially and all that's left to say is thank you for watching how can a regular person be talked into committing heinous acts upon another and could you be convinced to potentially injure or kill someone else i'm not talking about self-defense or during war on the battlefield but someone you have never met before and have had no interaction with previously how can perfectly normal people commit genocide like what we saw in the 1930s and 1940s in europe or even in cambodia in the 1970s amongst other events what causes people to be active participants in crimes against humanity if we take germany in the 1930s as an example what caused a large part of a modern country to be willing in crimes against people that have been their neighbors and community members for years it is a really fascinating thought experiment as when you think to yourself i could never do something like this or even this but what would it actually take for you to pull trigger push a button or pull a lever well this is where a psychologist set out to see what would be the minimum amount of suggestion for a regular person to administer a potentially deadly electric shock to someone they have never met before the simple but effective study would be known by the inventor's name the milgram experiment the actual experiment would not result in any physical pain but extreme stress and inflicted insight to the participants and this would create controversy with the study as such i'm going to rate it here five on my ethics scale this is mainly due to it being a fascinating dive into our hard-wired ability to obey an authority figure even to the point of murder welcome to the dark side of science stanley milgram was an american social psychologist born on the 15th of august 1933 in the bronx new york his parents were jewish and have fled romania and hungry during the first world war his background and family ties to europe would have an important effect on his later studies into social psychology as word came back to the milgram family during the late 30s and 40s of the atrocities inflicted by the nazi regime although in relative safety in the usa many of stanley's family members were directly affected by the holocaust after the war some surviving members of the family came to stay whilst finding a new life in the us a young stanley was exposed to the horrors experienced by his relatives and this would stay with him igniting an interest into the darker side of human nature in 1954 milgram received his bachelor's degree in political science from queen's college in new york initial applications to harvard for psychology masters were rejected but was eventually admitted the initial setbacks were due to milgram not taking any undergraduate courses in psychology at queen's college in 1961 milgram received a phd in social psychology he became an assistant professor at yale around the same time later on he served as an assistant professor in the department of social relations at harvard from 1963 to 1966 and this brings us very quickly on to his obedience study more commonly known as the milgram experiment stanley's experience of relatives going through the holocaust coupled with the arrest and trial of adolf eichmann in 1961 sparked an interest into finding out what could make seemingly average people take part in atrocities eichmann organised the logistics of the deportation of jews during the holocaust he made deportation plans down to the last detail working with other german agencies he also determined how the property of deported jews would be seized what was interesting about the trial was that he claimed he had not dictated policy but only carried it out and that he was merely a cog in the machinery of destruction essentially the i was only following orders defense this highlights the question that is following an order enough to convince someone to do something so heinous milgram would later say in 1974 when explaining the experiment could it be that eichmann and his million accomplices in the holocaust were just following orders could we call them all accomplices the experiment was pretty simple and would make use of three people the experimenter who was in charge of the session the teacher a volunteer for a single session and a learner both the teacher and learner would arrive for the session together and they would draw straws as to who would take each role participants were sourced via a newspaper ad saying we will pay you for one hour of your time in a study of memory the teacher and learner after finding out their roles were taken into a room where the learner was strapped into what appeared to be an electric chair and electrode pace was applied to the learner's wrist to prevent blistering and burns the teacher would hear this being explained and see this happen the experimenter who was dressed in a lab coat in order to appear to have more authority told the participants that restraints was to ensure that the learner would not escape the teacher was allowed to experience a sample electric shock similar to what the learner would feel before beginning the experiment the volunteers were informed that they would be paid regardless of the outcome thus removing any financial incentive to any results the teacher was led into another room where they could not see the learner but could hear them and the experiment would begin the teacher was then given a list of word pairs that he was to teach the learner the teacher would then read the first word of each pair and read four possible answers the learner would press a button to show his answer if incorrect the teacher was meant to administer a shock to the learner if correct the teacher would read the next pair of words each subsequent incorrect answer would mean the teacher had to increase the voltage in 15 volt increments they are also instructed to announce the voltage before shocking the learner pretty cruel you might think but there was only one actual volunteer in each test the teacher who unbeknownst to them was the real test subject you see the learner was actually a stooge and wasn't receiving an electrical shock and the chance drawing his straws to find out who would do either role was actually fixed meaning the teacher would always be the teacher also probably not surprising the experimenter was also in on it this meant that the whole experience of the teacher was controlled from the authority of the experimenter to the reaction of the learner to ramp things up in later versions of the study the learner would also shout out in pain when the voltage got too high the experiment would have a preliminary and a regular run the first was a practice of sorts where a learner would get three correct answers and seven incorrect ones which would yield a shock up to 105 volts the second or regular run the teacher would be told to read off a list of words and had to continue repeating it until a learner had gotten all of the pairs correct the volt dial range from 15 to 450 volts and to add further explanation for the teacher was labeled slight shock to danger severe shock above 300 volts the learner would kick on the wall and then no longer give answers to the teacher's multiple choice questions if the teacher showed any hesitation the experimenter was able to give one of four prodding responses in sequence the first was please continue or please go on followed by the experiment requires that you to continue and then it is absolutely essential that you continue and finally you have no other choice you must go on the experimenter could only progress to the next prod if the teacher refused if all four responses were reached then the experiment would end if not it will continue all the way up to 450 volts if the teacher asked any specific questions the experimenter could reply for example will the shock leave any permanent damage the experimenter could then reply with although shocks can be extremely painful they cause no permanent damage after the experiment an interview would be undertaken and the question how painful do you think the last few shocks you administered were the teachers were instructed to indicate their answer on a scale between one to 14 after which the teacher was reintroduced to the learner and the experiment was fully explained the experiments began in July 1961 at Yale University and 40 subjects would volunteer through this newspaper advert and the results would surprise all predictions the 40 men were from a cross section in society from various different age and career groups ranging from 20 to 50 during the experiment most test subjects showed signs of severe distress when administering the electric shock they observe sweating trembling stuttering biting her lips groaning and digging their fingernails into their own skin the discomfort seen shown that the subjects were aware of the pain the learner was experiencing pre-experiment it was expected that only a small amount of the subjects would administer the high voltage shock between one and three percent but this prediction would be way off of the 40 subjects all reached 300 volts at which the learner would bang on the wall and stop giving answers only five refused to go beyond this point four more went on to shock the learner one more time and then also refuse two stopped at the 330 volt level and one each at 345 360 and 375 volts respectively meaning that only 14 refused the experiment as prods this meant that 26 proceeded all the way to the end giving the highest available shock to the learner although most showed signs of discomfort and stress they still obeyed the perceived authority of a guy in a white lab coat the results were understandably unexpected as from the young age we are taught to not hurt others but with the addition of an authority figure the teacher would abandon this fundamental part of their moral fabric scarily there was no punishment for disobeying the experimenter nor was there any reward for completing the experiment as payment was assured from the start even more strange was the results were similar when a control study was undertaken with 43 unpaid students in Milgram's paper into the study he highlighted several particular conditions of the experiment that might have contributed to the high level of about 65 percent of compliance to the highest voltage level the fact that the study was being undertaken at and sponsored by Yale possibly reassured subjects that the experiment was aboveboard and reputable the perceived randomness of the selection of learner and teacher also could have factored in as a teacher may have thought that he could have been in the other chair hence he was exposed to the same risks the subject may have also have thought that as he had volunteered that he was obligated to help the experimenter and to the same extent that the learner had also submitted to the authority of the experiment the subjects were also reassured that although painful the shocks were not deadly and that compliance was built through to shock level 20 when the learner would no longer reply to refuse would cause a conflict situation where the wants of the learner and the experimenter were at odds with one another and decide with the experimenter was the path of least resistance so to speak the short duration that the experiment ran for meant that the teacher had less time to think about the actions resulting in little time for reflection Milgram would repeat the experiment in several variations to see if any of the conditions change would yield different results even when Milgram conducted the experiment in an unregistered office far away from Yale the results were fairly similar now to the ethical question was the experiment cruel well in my opinion no but it can leave long-term distress to the teacher especially if they administered the full shock for many the experience left self-reflection on how they had submitted to the authority of the experimenter ethical criticism came from the allowed discomfort of the test subjects where even though they had provided their consent the experiment should have been paused when the distress was observed however in his 1974 book obedience to authority an experimental view pushed back on his detractors saying that the ethical criticism provoked by his experiments was because his findings were disturbing and revealed unwelcome truths about human nature it is really open to debate as whether the experiment was ethical or not but regardless it was a fascinating dive into human nature the study would later be compared with another controversial experiment run by one of Milgram's friends Philip George Zimbardo at Stanford but that will be a subject for another video thanks for watching I hope you enjoyed the video this video is a plain difficult production all videos on the channel are creative commons attribution share alike licensed plain difficult videos are produced by me john in a sunny southeastern corner of london uk help the channel grow by liking commenting and subscribing and check out my twitter for all sorts of photos and odds and sods as well as hints on future videos i've got patreon youtube membership as well if you fancy supporting the channel financially and all that's left to say is thank you for watching just five years after the icorillumina tailings down failure in hungary similar images of communities flooded by contaminated mud would appear in brazil the failure of the fundale tailings dam would release 43 million cubic meters of iron ore tailings over an area of 668 kilometers of water courses from the dolci river to the atlantic ocean it'll be known as brazil's worst environment of disaster and would hold a mirror up to the country's mining industry but sadly lessons wouldn't be learned quick enough as such i'm going to rate this disaster here eight on my patented plain difficult disaster scale but only here five on the legacy scale as well we'll get on to that a bit later on the germano mine complex is based in mariana minas giraeus brazil the site is operated by san marco s a which is a brazilian mining company founded in 1977 the company is a joint venture between brazilian veil and english australian bhp the tailings dams in question at the site were used in conjunction with iron ore mining an industry which for every usable ton of iron ore concentrate around 2.5 to three tons of waste tailings are created these waste products need to be stored and that necessitates the use of storage ponds held back by a regular subject on this channel a tailings dam whilst we're here let's look at the process that creates this much waste product iron ore is vital in the production of steel obviously a massive important material for building of pretty much everything the all one's mind is run through a process of crushing grinding and classification during this waste materials such as sand and other undesirable matter are screened and either run through crushing again or sent to tailings storage areas the process continues during concentration of the ore where it is hydro cyclone to separate out slimes and the removal of silica the separated slimes are also sent to the tailings storage once the iron is taken out it is floated and magnetic or gravity separated before being filtered after which it is dried and turned into pellets for use in the production of steel but that is a really brief explanation and the process is far more complex in reality but let's get back to the main subject of the video the tailings and its disposal in the form of storage tailings ponds are useful in draining away the moisture from waste products which then they can be stacked on top of another allowing for relatively efficient use of space the gemano mining complex was no different and it employed this type of storage for its own waste created on site the tailings storage area was started in 2008 and was intended to contain a total of 79.6 million cubic meters of fine tailing slime and around 32 million cubic meters of sandy tailings over a 25 year lifespan the two types of tailings had different properties and as such had to be managed individually which greatly influenced the design of the dam the sand deposits were transported in a slurry and consisted of silt sized particles which allowed water to drain away rather quickly after being deposited but were not the most stable as they were loose and easily displacable the slimes were also transported as a slurry but were more compressible and permeable compared to the sand the design of the tailings was a drain stack variety the concept was to progressively stack the sands behind a starter dam with the slimes retained behind the sand stack the starter dam would be raised on top of the sands using an upstream style construction once structurally stable the area of the sands between the dam and the slimes is rather aptly named the beach this type of dam has one big flaw and that is the fact that the structure is lifted and built upon the uncompacted sand which if not monitored and maintained properly to keep dry can result in disaster to prevent static liquefaction free methods were used in the design first was the comprehensive drainage system underneath the starter dam the second was concrete drainage channels under the left and right abutments and finally keeping the beach at around 200 meters to prevent moisture from the slimes undermining the foundations of the starter dam it is thought that the allowable height increase per year is around five meters but the dam at fundow would be a victim of its own success as stated earlier the project was to last 25 years but by just seven years after its beginning the dam was holding back 56.4 million cubic meters more than half its expected capacity but throughout its life the dam was blighted with issues relating to drainage construction defects resulting in water management errors and saturation of the sand tailings an internal erosion event happened in 2009 and the intended 200 meter sand beach width was not being adhered to with slimes getting as close as 60 meters from the dam crest during 2011 and 2012 after structural failure of the concrete gallery beneath the left abutment emergency measures were implemented in 2013 it was decided to realign the dam on the left shoulder by moving it behind the section of the gallery to be filled with concrete this brought the crest closer to the slimes which would reduce the structural integrity of the dam originally the realignment was only to be for a short while but would continue to until 2015 which leads us on to the disaster at around half past 3 pm on the 5th of November 2015 a leak was discovered on the dam attempts to produce the water level were not effective as failure occurred around 50 minutes later around 43 million cubic meters of tailings were released down the sanitarium river valley the toxic tidal wave which was 10 meters at its highest overflowed the sanitarium dam and swept through beneath Rodriguez obliterating the village the small community was only accessible by unpaved roads and post-disaster rescue efforts were severely hindered the toxic flood continued down the Gao Axio and Dolcey rivers eventually reaching the Atlantic Ocean 620 kilometers downriver the flood killed 19 people displaced 600 families and at least 400,000 people had their water supply disrupted the environmental impact was truly shocking with around 11 tons of fish being killed hundreds of hectares of forest were destroyed and multiple cultural monuments feeding the brunt of the destruction all of these effects impacted the local economy and general standard of living for the communities around the area with food and water shortages interruption of mining activity severely affected employment in 37 villages and cities and a general ban on fishing and agriculture added salt to the wound this meant that people had fewer ways to earn money or even get food for themselves but what was the cause of the disaster we know that the fundale dam was questionable at best throughout its short working life but what made November 2015 the tipping point a panel was set up by the Brazilian government to follow Samico's own investigation into the failure state of the dam during the investigation documents were leaked hinting that the company were well aware of the structural issues of the modified dam and that collapse was very likely the information dated back to 2013 around the same time that the emergency realignment of the left abutment was undertaken the company ordered investigation panel released their findings in 2016 and the failure point is not much of a surprise it was found that liquefaction within loose saturated sands located at the left abutment started the disaster this was caused by slimes under the sands weakening the structure due to less than 200 meters between slimes and starter dam this process eventually resulted in the sands becoming unstable at which point liquefaction was triggered and the dam breached if the drainage hadn't failed in 2013 necessitating the realignment of the left abutment then the disaster would may never have happened which brings us on to the main cause improper construction of those vital drains Samico's activities were suspended after the disaster and were ultimately fined 20 billion dollars which is just under 5 billion US dollars but that wasn't the whole cost as compensation still had to be paid out to always affected this ran the company another few billion dollars now I mentioned right at the start of this video that although this was one of the worst it was definitely not one of the last tailings dam failures in Brazil as only a few hours drive away another similar disaster would happen just four years later this video is a plain difficult production all videos on the channel are creative commons attribution share alike licensed plain difficult videos are produced by me John in a sunny southeastern corner of London UK help the channel grow by liking commenting and subscribing check out my twitter for all sorts of photos and odds and sods as well as hints on future videos I've got patreon and youtube membership as well if you fancy supporting the channel financially and all was left to say is thank you for watching it is the 4th of January 1986 and 26 year old James Harrison is working at the Sequoia fuels corporation site in a scrubber building he begins coughing little does he know that he has inhaled a deadly cocktail of hydrofluoric acid an alarm is heard and he escapes the building but the chemicals he had ingested will prove to be fatal the building he was working in was 15 meters away from a ruptured tank which held uranium hexafluoride a compound used in the enrichment of uranium for the nuclear industry the event would release 29 500 pounds of material into the atmosphere and would expose and hospitalize many workers it would not be the first time but operator kema g would be entangled in a nuclear controversy with the Karen silk would scandal in the late 1970s and it would not be the last as like many similar events the release would be the result of improper management multiple shift changeovers and product handling issues sadly the working class employees would pay the price as such I'm going to rate this disaster here five on my disaster scale but only three of my legacy scale due to the event being quickly forgotten because of another bigger disaster in 1986 the road to 1986 started back in 1968 with kema g breaking ground on a new uranium processing plant the site is near the town of gore vn and weber falls in eastern oklahoma not far from interstate 40 the site was intended to be used to convert yellow cake into gaseous uranium hexafluoride and was licensed as a fuel cycle facility regulated by the nuclear regulatory commission operated under kema g nuclear corporation production started on site in april 1970 with a conversion capacity of 4550 metric tons of uranium per year working 24 hours a day with a four shift pattern this subsidiary split into two companies in the early 1980s in which one of them sequoia fuels corporation would be responsible for owning and operating the site the process in its most basic explanation is yellow cake in uranium hexafluoride out but we will want to have a look in a little more detail uranium concentrate is weighed sampled and then digested using nitric acid to produce urinal nitrate which then undergoes a solvent extraction process where impurities are removed from the product the impure urinal nitrate solution enters at one end of the solvent extraction circuit while a mixture of organic solvents that have the ability to absorb uranium enters at the other passing encounter currents past each other the two solutions enter six stages of mixing and setting where the uranium is extracted from the solution and the impurities remain in the acid the baron acid solution is neutralized and is further processed to remove radioactive uranium daughter products such as radium which are then stored on site as a sludge the process raffinate which is virtually free of radioactivity is then stored on site in holding ponds to be reduced by evaporation the solvent extraction solution containing the purified uranium is re extracted into water in a countercurrent pulse column and enters an evaporation and boil down process evaporation concentrates the weak urinal nitrate solution into molten urinal nitrate hexahydrate or UNH this intermediate form of uranium is then converted by a thermal decomposition to uranium trioxide in a denitration process furnaces heat the denitrate troughs which are equipped with agitator arms that constantly stir the UNH the U03 drawn from the denitrate troughs is shaped into orange colored pellets measuring about a millimeter in diameter grinding pulverizes these pellets into a fine powder the powder is reacted with hydrogen in a two-stage counterflow fluid bed reactor to produce u02 as a powder this powder is then put into a two-stage stir bed reactor also with a countercurrent flow hydrogen fluoride is added and the u02 is converted into uranium tetrafluoride the uranium tetrafluoride is then transferred to a tower reactor where reaction with elemental fluoride creates the final product to solidify the uf6 it is sent to coal traps it is then heated again to turn into a liquid for pumping into storage tanks once inside the uf6 solidifies as it cools down to room temperature these tanks are rolled around on carts running on tracks the cart and tank before filling are rolled onto a set of scales it will be kept here throughout the filling process to measure the net weight stopping the filling of the cylinders on site is done manually by operators and there is no automatic cutoff during filling via a flexible pigtail line uf6 is kept at a temperature of around 210 degrees fahrenheit it can take several eight hour shifts to fully fill a tank and all of this is dependent on the production rate on site after filling the tank's valve is closed and the hose is removed and the product is moved via forklift to a steam chest which is used to keep the uf6 in liquid form cylinder number e2047 a model 48 y tank passed a 20 point inspection in october 1985 this was intended to find any damage to the valve or welds on the unit and is conducted by an experienced and licensed engineer the cylinder is made up of five apes of an inch thick steel the body is approximately 117 inches long with an inside diameter of 48 inches in total the empty weight of such a container is 5200 pounds and is not allowed to exceed a net weight of 27500 pounds the same inspection is undertaken by a shift manager before any filling takes place which is exactly what happened on the 3rd of january 1986 at 10 am filling would initially take place at two different traps providing 1230 and 10 000 pounds of uf6 during the morning shift during the evening shift a further 12200 pounds are added bringing up the net weight to 23430 pounds next came the midnight shift as part of the handover the operator was informed that he would be continuing to fill the tank the operator is to fill the tank to the target weight of 27500 pounds but he notices something strange when the scales won't go above 26400 pounds after investigation the operator notices that one of the cylinders cart wheels aren't completely on the scales this is a problem as the weight is not being properly measured after several attempts to move the cart eventually he manages to get a new reading on the scales which can only show a maximum of 30 000 pounds the operator is shocked to find that he's reading 29500 pounds in effect bottoming out worried the operator consults his supervisor who suggests using vacuum from the previously emptied coal traps to remove the excess weight the evacuation begins at 6 15 am and initially around 150 pounds are removed in a space of 10 minutes at the end of his shift he reports to the relieving operator of the overfill due to the cart being off the scales as the day shift went on the operator who ironically was the one who initiated the filling the day before noted that no more product was being evacuated as we saw before once the uf6 reaches room temperature it begins to solidify the assistant supervisor and the operator then decided to move the tank into a steam chest the placing of an overfilled tank into a steam chest is a direct violation of company policy at around 11 30 am the tank ruptured after 2015 minutes of heating the force of the explosion damaged the top of the steam chest the uf6 vaporized and combined with moisture in the steam chest released a highly acidic gas this deadly chemical made its way into the facility ventilation system it was here that james harrison inhaled the acidic gas the plume left the plant had traveled 29 kilometers due to a strong wind heading south past the i40 and over several sparsely populated residential areas the vapor entered the ventilation intake vents of the process building injuring the employees within most of the approximately 40 workers on site at the time were in the lunch room upon realizing the danger many escaped but had to pass through the cloud the evacuation alarm was sent and the ventilation system was switched off the rondevue point for the site workers was luckily upwind where they observed the release for a further 40 minutes the company didn't really have an emergency plan but the gore police department was called and they notified the sequoia county sheriff's department and oklahoma highway patrol to close down the i40 and highway 10 harrison was driven 13 kilometers to a nursing home for a canister of oxygen before he was taken to sequoia memorial hospital however upon reaching the hospital it was discovered that he was ill equipped for treating harrison and sent him to the largest sparks regional medical center in fort smith arkansas another 34 kilometers away he would die at 3 p.m soon after arriving at the emergency room the fatality was a result of the company not having an adequate emergency plan arrangement with local hospitals in total 100 people were sent to hospital with 21 severely injured most of the contamination was within the boundary site in total around three curries of radiation was released in comparison three mile island released over four times that at 13 curries during the investigation it was found that the cylinder was not defective but instead succumbed to the extreme pressure caused by an overfilled container being heated and the uf6 expanding past the point of no return the site after cleanup would continue to operate until 1993 but it would see another release in 1992 this coupled with storage ponds leaking into the ground meant that the site would need a long time to be fully decommissioned and cleaned the incident didn't stir much in the media as you would have thought but luckily for kermah gie but just a few months later chenobal would happen this video is a plain difficult production all videos on the channel were creative commons attribution share like licensed plain difficult videos are produced by me john in a sunny southeast in corner of london uk help the channel grow by liking commenting and subscribing check out my twitter for all sorts of photos and odds and sods as well as hints on future videos i've got patreon and youtube membership as well so if you fancy check them out to support the channel financially and all that's left to say is thank you for watching do these images look familiar well if you're a regular plain difficult watcher then you might be thinking is the title wrong for this video as looks suspiciously like the mariana dam disaster but sadly this video isn't a remake of the 2015 tailings dam failure instead today we're looking at another tailing down failure in brazil in 2019 just over a two hour drive away it seems that history is doomed to repeat itself and tragically in events like this lives are lost and the environment gets polluted today we're looking at the bruma genu tailings dam collapse and flood as such i'm going to rate it eight on my plain difficult disaster scale and also eight on my legacy scale due to the disaster killing more than the fandal disaster and that lessons never get learned the old saying lightning doesn't strike twice obviously didn't take into consideration the company valet okay in my last video i was calling the company veil rather than valet which is my bad the company was one of the partners that ran the fandal site another failure of a tailings dam in brazil in 2019 resulted in a death toll of 259 and 11 people missing the actual trigger for the disaster is unknown but the journey to the monumental failure is oh so familiar to fandal and that is improper water drainage the corrigo de feijo iron mine is a site upstream from bruma gene hall mean as jeres brazil dam one which would be the epicenter for the disaster at the mine was built in 1976 by the feteco mineral company in 2001 the site was taken over by valet sa right now let's take a look at the design of dam one at bruma gene hall it was constructed using the byproducts of mining including waste rock and tailings which were produced during crushing of the unprocessed ore and the subsequent ore concentration process for the ore concentration process water was used to assist in the gravity separation of ore particles from the waste tailings it was also used in transportation to the dam the whole purpose of the dam structure was to dewater these waste materials for long-term storage the dam was constructed in 15 stages between 1976 and 2013 this involved beginning with a starter structure after which it is raised in stages by constructing berms on top of previously deposited and dried tailings although space efficient this construction method is risky as the foundations of each subsequent raising is built on potentially unstable material for this method to be effective proper drainage is essential in preventing liquefaction of the tailings these were tackled in two ways the first was to help remove surface water and generally consisted of a series of surface canals that were designed to route the surface water run on precipitation and sluiced water to the cortical diffigile beyond the toe of the dam the second was to remove moisture from within the tailings by the formation of an open beach which would promote a desiccant state within the sluiced waste material the original starter structure didn't have drainage but subsequent construction lifts had tow drains by 2013 the dam had reached a height of 86 meters and no new raisings were done on site however tailings continued to be placed until 2016 when the ore concentration moved to a dry instead of wet process reducing the need for a tailings pond but just because the tailings had stopped being added to the impoundment didn't mean it could just be abandoned and forgotten about there was still the issue of the water in the pond behind the dam and the keeping of precipitation away from undermining the structural integrity of the site the level was significantly reduced by May 2016 leaving a shallow depth of standing water in the impoundment far from the dam by 2018 a number of issues in the dewatering system were highlighted which included pump failures drainage channels being blocked and pipe work being disconnected during maintenance all of which were a recipe for disaster in an effort to reduce water levels within the dam deep horizontal drains were used in 2018 these necessitated drilling into the dam to install a metal casing followed by a 50 millimeter PVC horizontal drain 14 of these drains were installed across the various stages of the dam until number 15 when on the 11th of June 2018 as drilling went through the starter dam at the toe in the central region movement was recorded in the structure the ball collapsed and mud flowed from the hull causing seepage to be seen from the dam the area was cemented and grouted and a deep horizontal drain program was then abandoned towards the end of 2018 two subsurface exploration programs were undertaken that were intended to collect information on the material properties of the dam and natural ground this again necessitated boring into the dam eight bore hulls were drilled between December 11th 2018 and January 2019 and nine were dug on the other project one more on the central portion of the dam at the crest of the eighth raising to install new piezometers was being dug on the 21st of January 2019 and this leads us onto disaster on the 24th of January the drilling was dug to a depth of 65.5 meters below ground elevation the next day the 25th the drilling team returned to work and continued to extend the hull to around 80 meters which is around the point that the drill bit would go from tailings into natural ground just after lunchtime on the 25th at around 12 28 p.m dam one experienced a catastrophic failure beginning at the left abutment what was rare for this kind of disaster was that the whole thing was caught on video in this perfectly shot footage as you can see failure was sudden leaving little chance for anyone to escape the flow of mud the released effluence rapidly traveled through the mines canteen and offices as well as houses and anything in its path the flow made its way into the Peralpeba river turning its banks into that characteristic orangey muddy color the disaster released around 12 million cubic meters of tailings the metals and the tailings would eventually work its way into the river's soil affecting the region's whole ecosystem the death toll of a total 270 people was largely made up of valet employees with a few railway workers listed amongst the missing who were never found infrastructure damage was in the form of road railway and an iron ore railway bridge destroyed three kilometers downstream from the collapsed dam unsurprisingly the company took a financial hit with a 250 million real fine the day after the event but as always with these things that was just the tip of the financial iceberg valet's assets around three billion us dollars were frozen which in part tanked the company stock just recently in 2021 an agreement was made between valet and the government to repair all environmental damage and pay the families of the people killed seven billion dollars total in compensation employees of the german contractor tv sud tasked with monitoring the dam and a number of staff at valet were arrested on suspicion of murder falsification of documents and environmental crimes the local population was hit hard economically as like with fundale agriculture was severely affected with crops ruined and cattle killed in the flood fears of another dam failure at number six which was next to number one led to evacuations of nearly 24 000 people on the 27th of january but what caused the so fast and dramatic failure of dam number one surveys undertaken leading up to the failure did not show any hints of the fate of the structure but survey markers located along the dam crest that were checked manually approximately once a month were not sensitive enough to pick up small movements the panel investigation highlighted several possible factors that together caused the instability of the dam the design was a steep upstream constructed slope water within the tailings impoundment was allowed to get close to the dam crest which resulted in the depositing of weak tailings a lack of significant internal drainage that resulted in a high water level the dam particularly in the tow region leading up to the end of 2018 higher rainfall was experienced at the site further increasing the water level which was exasperated by the surface draining system being compromised all of these might have been okay in a more stable design but sadly the upstream style is inherently poor due to the foundations of the dam being on loose saturated heavy and brittle tailings that had high stresses within the downstream slope which created a marginally stable dam this is a plain difficult production all videos on the channel are creative commons attribution share like licensed very difficult videos are produced by me john in a not so sunny southeast in corner of london uk help the channel grow by liking commenting and subscribing check out my twitter for all sorts of photos and odds and sods as well as hints on future videos i've got patreon and youtube membership as well so if you fancy supporting the channel financially you can check it out there and all that's left to say is thank you for watching