 First of all, good morning, good afternoon, and welcome to the first IHE Delft Alumni online seminar of this year. As you know, or many of you know, this seminar series on topics selected to suit the interests of alumni and partners, of course, are open to a broader audience, so never hesitate to share the invitation or later the video with your colleagues or person who may be interested. My name is Maria Laura Sorrentino. I work as a alumni advisor officer at IHE Delft, and it's my great pleasure to organize and to moderate these events with the technical support of my colleague B.J. Before I start, again, I would like to remind you to stay in silence mode, to about disturbances, and you are welcome to introduce yourself in the chat mentioning your name, country, and place of work. After the presentation, remember that you will have time for questions and answers, so I invite you to write your questions in the chat during the talk, so I can read them to our guest after he finished his presentation. In the coming days, you will receive by email the recorded video and also you can find that video and the previous seminars on the YouTube channel of IHE Delft in the session, Alumni Online Seminars. Good. The topic of today, Provision of Water and Sanitation in Challenging Conditions, Experiences in Antarctica, will focus our attention on that continent. We know it is a planet, hold it, and win this continent, and is home, not only penguins and other animals, but also a growing number of human scientists conducting research in this unique environment. Like all humans, scientists produce human waste, which has to be handled in a way so that it doesn't put the pristine environment at risk. The guest speaker of today, Dr. Hector Garcia, is Associate Professor of Waste Water at IHE Delft and will share with us his experiences from the mission he had to the Uruguayan Scientific Base Artigas on King George Island last April. He was there as part of the team comprised in IHE Delft and Technological University of Uruguayan experts, both alumni, that you can see the tree on the picture, who study new ways of water treatment to improve the current sanitation situation by allowing the reuse of wastewater. I would like to give the voice to our guest speaker, Dr. Hector Garcia. Hector, please. Yes, good morning or good afternoon or good evening. Thank you, Maria Laura, very much for the introduction and also thank you, EJ, for organizing this online seminar and welcome to everybody to participate in this, in today's seminar. My name is Hector Garcia. I'm Associate Professor at IHE Delft in the research group of citywide inclusive sanitation in the water supplied sanitation and environmental engineer department. So in particularly the topic that I will be discussing with you, the provision of water and sanitation in challenging conditions, the expertise, the experiences in the Antarctic, I would say it's well aligned with everything that we do mostly at our core of citywide inclusive sanitation that is pretty much finding alternatives for providing sanitation when there are not sewers in a decentralized setting but also in a non-sewer setting and also linking from our sanitation perspective. If we don't provide good sanitation, we will have water quality issues that will impact our water quality on the drinking water. So today we will cover both water and sanitation interventions in such a different environment that is the situation that you observe in the Antarctic. It's not only cold and windy but also it has other challenges to not only to get there but to work there. So as Maria Laura was mentioning, this project has been, so this mission was a collaboration but there is an ongoing project that is carried out between UTEC. UTEC is a technological university in Uruguay that I'm also affiliated there. The Uruguayan Institute of Antarctic, so pretty much the country as many others in the world, they have a research institute there that is located in the Antarctic and of course the project is also conducted by IHE there. So this is a nice combination of institutions that allow to make this mission and this research possible. So first I will start describing the place as you can see the Antarctic is a large and big continent and the Uruguayan base is located in the King George Island as you can see in this figure over there. So the way to get there to the island is through the airport that is managed by Chile. So and there you can see at the left there is the Chilean base and at the back of the slide the airport. This picture was taken in the winter, it's not the picture that we took in our mission there. So at the right you see the Russian base and at the right in the next base you can see the Uruguayan base that the name is in Spanish is Base Científica Antarctica Artigas, so it's B-C-A-A. So the way to get there is through the airport, through the Chilean base it's not airport as you used to see an airport, it's more you know I would say a very primitive airport but it's the only way to access there. So in that island there are many other countries that also have research stations and as you can see in the slide many countries in the close by to the Uruguayan base, the Artigas base, so we can see also that Russia has a base, Chile, South Korea, Argentina, China, Czech Republic, Poland, Peru and also Brazil. So there is a nice possibility there of you know doing research together between different countries. So this is the, so I'm showing a picture there when we were arriving to the Antarctic the mission was carried out a few months ago at the end of the of the summer in the south hemisphere. So the Antarctic is pretty much closed during winter time that is from end of March to November. So it is only possible to go there as a researcher between the summer in the south hemisphere between November and March. So all the things that I will go into show were done during the summertime so that's what you will see a little bit of us know but but not much because remember is summer. So there is a were arrival so we were arriving at the airport that is controlled by Chile so then you see at the left side of the of both of the left slide you can see the Chilean base and they have like a small town over there and at the right side is the Russian base and then from that base you can take a boat to go to the South Korean base you cannot go by by road transport only by boat. Same thing the right side of the slide shows a different view of the Chilean and the and the Russian bases there. So the as I show you in the first slide the the Uruguayan base our our destination it was more to the right side more if we look and on on the map is more to the to the west of the Russian base but the Uruguayan base can be accessed by by road transport so and but you know in the summertime there was not much snow at that time but in the winter you can imagine that it snows a lot so it's difficult to to to move there by you know by truck or by or by van or by car so that's what you're seeing in the in the screen is the the typical mean of transportation there in in Antarctic it's like a snow a snow van or a snow truck so then upon our arrival to the base we were picked up by by staff from the Uruguayan base and we were taken by by that transport to the base and then you already have a feeling from seeing that picture how the the roads looks like there so pretty much there are no roads so and that is why you need some sort of different transport to to get there all right so this is our destination in Antarctic this is the Uruguayan base so it's the the the bay it is it's very nice I would say it's one of the the on on that island is of the places that I like the most not because it's the Uruguayan base but because the bay and the and the landscape in that part of the island is is really beautiful so as you can see that's for the different buildings each building has a meaning also the way that the buildings are distributed in in small and different buildings is you know because if if an accident happened not everybody's in the same building at the same time and the building that you see at the right side of the picture the light blue and white it's pretty much the dorms what was most of the people live but not the military stuff that they they stay in in separate buildings so this is now a different view of the of the base from the from the other side this is from the west the other was from the from the east but pretty much is the same information I told you so here is the project team that were there so from from left to right is better in L'Olkema it's a research laboratory staff from IHE Delphi in the center it is myself and on the right is a miss Alejandra Sabo that is associate professor with Utec so that was the team that conducted all the activities there so but before going into the into the technical details I just wanted to give you a brief view of of the of what we see over there so some sightseeing of the of the Antarctic this is a nice glacier that you see right from the from the bay in in the base it's it's at the east side of the of the base and this is the view that you have at the west side of the base it's the this glacier over there is around four kilometers a walking distance from there so the landscape is is beautiful it was summer so you know it was not much ice and snow but still was a decent amount so this is a sea level right so end of summer sea level that if there is still snow and ice there so that you know that could give you an idea how cold is there same views of the glacier at the left and and the right and also in Antarctic the fauna is very interesting so we saw many penguins of of course there are some procedures and regulations how close can you get to to to the animals there for not disturbing the the local fauna and also other type of of fauna we we saw over there and I highlighted that with the white circle because it's very difficult to distinguish between the seal and the and and these little stones over there this is a view of what you see actually from the base I just run a video so you can have a better idea of the of the landscape over there are how things look like over there and and again a picture that that this is the the summer so you can get an idea how how difficult it could be there in the in the winter so this is the base from the bay from south to from north to south in this case and this give you a better idea of the buildings and and and of the entire camp over there all right so and now not everything was pleasure and relaxation we also did some work over there and this is what I would like to to show right now so we wanted to do sort of an audit or find out what is the situation regarding water and sanitation so first things that we did is we bought a lot of a portable and movable equipment and we took it there so we were discussing with the people from the base well in advance so to to find out this equipment like reagents and chemicals portable equipment for for conducting sampling and analysis of things over there and then we did a plan so we wanted first to find out what is the sanitation situation and then so in Antarctic if you are operating a base that on average has less than 30 persons per year let's say so you don't need to provide any wastewater treatment in the plant but at least you need to manage your your waste your fecal sludge and your waste but by means of septic tanks so on average this is a small plant in the base sorry in the in the summer it may receive up to 50 person total combining military staff and researchers but in the winter there are only eight staff that that lives there all year around so on average the the base is below 30 so there was no need to to provide wastewater treatment but anyways there is the interest of the of the country to you know it's a very pristine environment so they wanted to move ahead and find out what is the situation of the septic tanks what is the pollution of the of the area and if things are not properly working or are not you know the the best management practice to to implement wastewater treatment system and that was part of of the objectives of this mission so we started with a sanitation sampling campaign so for that we define different sampling points there are two slopes in the in the base with the where the water flows from the hills to the bay so and then in that they they form two small creeks and then so and the septic tanks are located both at the east and at the side of the base what I call their line a and line b and all the septic tanks are arranged following that that slope so and that is where where we define our sampling points sampling points one two and three refers to the septic tanks that I would say that collect the most waste because it's from the dorms where most of the people lives sleep then sample four and five are the kitchen six and seven kitchen and there is also restaurant is the place where people eat will have all the meals there and there is sort of place for recreation so now also a lot of waste is produced there six and seven is the laboratory ten and eleven is where some of the military notation live sleep there and eight and nine is the gym and the laundry so we we organize the sampling there so and this is in this slide you can see those little creeks that are mentioning and how the water flow from the the higher elevation to to the sea and the left side you can see the creek and on the right side you can say you can see the mouth of that small creek into the into the ocean or into the sea this is the other side the west sorry this is the east part the line what we call line b and here you can see the other septic tanks how are they organized from the kitchen from the laundry from the gym in in in these two pictures and this is another view from the from what we call line b that is the west side of the of the base with the septic tanks organized in in that way so we were taking them samples so as we planned right so first we started with the septic tanks from from the dorm and this is you know how the the septic tanks looks there are big tanks of five or ten cubic meters that that pretty much act as a septic tank very simple septic tanks where the sludge is settled and then there is a an overflow an outfall for the for the supermate and so and then you can see how the supermate and leave the septic tank and if we zoom in so well you can see that the treatment is very elementary or there is no treatment at all just a maceration or just a settling of of the sludge and then the the I mean the treated partially treated or untreated with water leave the septic tank through the through the overflow right and this is in this point is that we what we sample so also you can see the runoff of of the septic tanks and even you can see some green greenish vegetation or things growing there so that shows that that this may be already a source of a pollution so we took several samples there for that we will equip with this sampling device this is how the septic tanks looks from inside so we take many samples we store the samples and then we took it to the lab to conduct many different physical chemical analysis same thing we did in the kitchen same procedures same septic tanks that they were providing in this case you know if you have a kitchen so you may have grease so you need to have these separators for for the grease but the concept of the septic tanks were the same and particularly here they combine not only the kitchen waste I mean the kitchen wastewater from the sink that has a high grease content but also they were a few toilets there so everything was combined here in the septic tank same same design and we did exactly the same procedure for collecting the sample storing the sample and also in all the septic tanks we did some on-site measurements taking sensors to measure pH conductivity dissolved oxygen and things like that we did that in every single septic tank so then we move on into the lab the lab it has two different septic tanks one for the for the waste that came from the sink pretty much residuals of traces of chemicals when you wash out things in the lab and the other is there is a toilet in the lab so the other collect the wastewater of the fecal sludge or black wastewater from from the toilet so very different type of waste so very different type of sludge or wastewater that we collected there everything was covered another thing I didn't mention because you know now for me it's a little when you see things on a daily basis it doesn't ring a bell but now I'm noticing that is important that of course it's a winter so in the in the winter temperatures get really low so if you see these two cables here these are to to feed a heater so with electricity because if they don't heat the septic tanks it will get frozen right so that is why this is continuously heated all year all year around and and that is the same that that stands for every single septic tank this is from the gym and from the laundry also we sample the the septic tanks and also over there as you can see that's the septic tank actually this one was the the one that was working the best this is this was the best the best one in terms of of performance so this is the tank how we sample the tank and over there you can see the the the outflow here so and as you can see the the water the color is a little gray is that of course septic tank does not provide such a great treatment and that is why the the the Antarctic Institute wanted to suspect that they could do better so we were measuring there with the sensors and this is the final one is the military notation where where the the staff leaves also there is a septic tank and there is an outfall of that tank and we did exactly the same okay so that was the the first our first goal was to find out what was the situation you know if could you please close your microphone please because there is some noise in the in the audience thank you so the first goal was to find out what what was the the status regarding this annotation we know that is better having septic tanks that having nothing the Antarctic Treaty force all the bases to have this type of septic tanks but we can do much better and that was the idea of doing this finding out what was the current situation and how can we improve but also we wanted to see the impact in the drinking water or you know or in the in the creeks in the environment so and also we did a sampling plan just to determine the the water quality of the surrounding so and we similarly as we did with for sanitation we also did for water and we but the the sampling points are a little different so my most important one I would say was the the creek that that creek that I show you that run at the east side of the base this point over here this line over here this is the creek that I start running here and end up in the mouth of the sea so for that we define four sampling points the upstream upstream of the base that is this point number one in the middle of the base there is already a septic tank over here as you can see and you know this already may contribute with some runoff from the outfall and there may be some issues here then the sampling point three is directly at the outfall of the septic tanks from the dorm and the sampling point number four is at the mouth of the river but also we wanted to find out what is the status of the of the drinking water in the building so in the water tanks in the tap water same in the kitchen and also we measure and probably it's better to see in the next slide the picture during the winter this is a creek that I was referring before that this is the dorm but also we wanted to see the the quality of the of the water that they they are taking to for water supply for drinking water without any treatment they just pump the water from the lake and drink it as it is without any chlorination without nothing here is a very pristine environment and there is there are nothing here so you know it's it's relatively safe to drink the water in that way okay so here are some pictures of the different sampling point from the water this is upstream of the of the creek the first point that that we monitored before upstream of the base so there you can see the the the sampling point better and how we were sampling this is second point that there already may be some impact due to the operation of the of the base also we collect a sample and then we analyze then the number three this was the out close to the outfall of the dorm so probably here is where we were expecting to see the you know major pollution there in this point so this is the outfall of the septic tanks and this is the runoff and here is where we were sampling and the final point was over here in the mouth of the of the creek to to the sea so here okay probably we we were not positive what what we could expect here i almost fall down in the creek because it was too windy so i was happy this is me i was happy collecting the two bottles and and still be dried that is not a minor thing over there and there are the little bottles that that we collected for for the sample so this is inside the building and here i wanted to show you that every building has or every facility where there are valves where there are pipes or whatever they are equipped with heaters because in the winter it gets really cold over there and the pipes could get frozen these are the storage tank these are the pumping system to provide water from the storage tank to the to the tap and also we monitor in the water quality of the tanks so there are this is a population of some type of microorganisms that grow there that are they don't have an impact on the on on public health but but still is a little not nice to see that over there so one of the recommendations that we did is to clean the tanks and more often so we measure all the water quality with sensor but also we sample to to measure later on so here is the well the location where we sample from the top in this building in the dorm of the of the place and also we sample in the kitchen in the storage tank in the water tanks in the kitchen and in the tap and so we also took a few samples of some lakes that was close to the to the base from this lake they were not taking the the drinking water but anyways we wanted to characterize that water and of course we took the water from what is called the Uruguay lake and this is the lake from from the drinking water is taken here you can see there is a pump a submersible pump somewhere here and from there as you can see in the screen the drinking water is taken by a pump up and then the water is the the water is then distributed to all the different buildings through these pipes and here these boxes that you see in between these where the valves are to open and close and these are also provided with heaters if not in the winter everything gets frozen and then you can see the pipes they have some slope so they do the operation of pumping water two times a week and when the operation is done they need to empty the tanks if there is water remaining in the the pipes they need to empty the pipes if there is water remaining in the pipes they will get frozen and you know pipes will break so it's quite challenging and these these are the water distribution line and these are these small boosts where the valves are placed and that are all the time heated so here is the location of the pump for for taking drinking water and this is also a place that we were taking a samples of course we didn't do that there are professional divers there that went into there and they take a nice samples for for us to to analyze we stores some samples we analyze theirs another we take it with us to the continent to do more intense physical chemical determinations so this is the lab and beren is carrying out some analytical determinations there so this is the lab with a nice view of the of the dorm so and then yeah we we conducted many different analytical determination we have cooler to preserve the samples and we did all the all the nasty samples it was very smelly the lab also we did microbiological determination total coliform fickle coliform and we were able to do everything there in in the facilities the lab facilities look very good all right and now briefly I wanted to show you some results remember we find out the water quality of the septic tanks and of the creeks pretty much so we split in two and I will just mention some interesting things when we analyze the septic tanks of course this is the outfall of the septic tanks of course we find out some a lot of total c of d because there is a lot of of total solids and volatile solids and of course in the septic outfall we find out not only total coliforms but also fecal coliforms and we find fecal coliforms that is an indication of fecal contamination right so okay we were expecting to find that in in the septic tanks and in the in the outfall of the septic tanks so this is in the tank but also we find some total nitrogen ammonia well of course c of d total solid volatile solid fecal coliforms as I told you we also measure pH conductivity dissolved oxygen temperature with many different analytical determination and in in every single septic tank so I'm just showing a few in in the kitchen so there was some anaerobic of fog so fat oil and grease so the pH it makes sense that we find out a low pH but I will not go into technical issues in the kitchen also we find out in the septic tanks total coliforms and fecal coliforms here is combined the waste from the kitchen with the waste from the toilet so it makes sense to to have that and also the COD the total COD was was very high over there also in the lab when we were measuring the the waste that was coming from the sink there was not fecal contamination but when we were measuring from the the septic tank from the toilet of course there was a fecal contamination there and same thing from the laundry if we measure the septic tank outfall we find out total coliform but not fecal coliform they were not a toilet there so we didn't see any a fecal contribution there then in the dorms of the of the staff yeah of course we we find out a fecal coliform as well so the conclusions of this determination that of course if we have septic tanks and we have an outfall so there will be high chances that the water pricks that run next to the septic tanks they may be exhibiting some sort of of pollution right and that is what we wanted to find out but not only that because it's kind of obvious but also we wanted to see from analyzing the septic tanks what is the load of waste that is being produced in terms of liters per day but also in terms of pollution or concentration per day so in case that we will design a wastewater treatment plan we know exactly what is the load that we will need to treat and what is the characterization of that of that waste all right same thing we did for the drinking water so for the drinking water so this is the sampling plan that I was mentioning before and I would like to focus on on these four points over here on the creek upstream the base and as we move downstream or as we move down into the basin so point one two three and four so this was the point one also we determined very almost the same parameters and I would like to focus on total coliforms fecal coliforms and of course E. coli so upstream the base they were non detectable so the creek was super clean but already when we move down to the first point that there may be already some affectation from the base we started to see total coliform but still the fecal coliforms were non detectable so we cannot conclude that there were a fecal contamination of the of the creek but then when we move down to the next point where we have the runoff of the septic tank for the dorms more than 30 40 persons could live here in the summer so we already find not only total coliforms but also fecal coliforms so here it shows that indeed you know having septic tanks without any further treatment it may have an impact but also we measure some ammonia there so this is in microns per liter so and this is not in the septic tank this is in the creek that receives a lot of a water flow so it's it receives a lot of dilution so the fact of finding some ammonia here it's also really indicate and also fecal coliform that indicates that that dilution is not strong enough to dilute completely these parameters so ammonia here I just wanted to highlight that it's in microns of nitrogen per liter it was milligrams would have been too high so it's 0.1 milligrams per liter but it's still high and then also what we were very surprised that at the mouth of the creek also we find out some fecal coliform there and also some ammonia so even here there are no septic tanks so even after the dilution effect is not good enough for so that we still find out those compounds all right so that's also we measure the water quality in the kitchen the water quality in the lakes and that was super fine we didn't find any coliform or any fecal coliform we would just find in the creeks next to the septic tanks but okay so we wanted to see how the other bases do what what do they have for the provision of water and sanitation and first we visit the bases that were around so to go to the Chilean base we passed through the Russian base that they have a even a very nice church over there in the in the Antarctic but we didn't visit much the the facilities only the source of drinking water that they share with with Chile so and this is the the view of of the Chilean base over here so and we have a very nice visit to the base we were received by the general of the air force that the air force is running the base and they gave us a very nice presentation on how they handle the water and sanitation and even we have some hot coffee and cookies that are always welcome and at the base there they didn't have septic tanks what they did they provide these pipes for collecting the wastewater these are kind of you know sewage more like condominium sewage so they have some slope and they have some insulation and that you know since the when you flush the toilet the residence time of the wastewater is little the we providing that insulation there and that the slope is okay for avoiding avoiding that the that the wastewater gets frozen these are the pipes and similar pipes as you can see here are coming from from all the from all the little houses there are some cameras to inspect the you know if the wastewater is flowing properly and here it goes to a wastewater treatment plant but also they wanted to do something different and innovate innovative so and they provide the wastewater treatment to to that wastewater using a worms and so for the worms they have these good chips and below these good chips there are worms that are degrading the the organic components of the wastewater and so after that the wastewater is discharged but then they have this kind of trap for for trapping all the worms that if not will escape escape with the wastewater but these are the little worms that they have to to degrade the organic components of the wastewater but also they have another wastewater treatment plant that is more modern or not modern the other is more than I would say more is more standard that is based on the conventional activated sludge process and so this is how how it looks all right and this is the discharge of that wastewater treatment plant into the into the water so what what is next so what is next now we wanted to we find out that indeed having septic tanks is something is good but it's not good enough if we really want to clean the wastewater before discharge so now in the next campaign over there we are going to evaluate a portable wastewater treatment plant that is named a membrane bioreactor system or based on membrane bioreactor technology to clean the wastewater in the in the base so this is we will take a portable system as you see in the previous picture that it can be easily transport to to Antarctic by by the plane and it can be easily located next to the dorm and this is the usually the water quality that you get at the left is the raw wastewater and at the right is the clean wastewater that that system produced the system has some membranes that are submerged in the tank so the wastewater is biologically treated and simultaneously is filtered by a microfiltration membrane that explains such a high water quality so and then we are going to place the system here next to the dorm that is where most of the wastewater is produced that that is the main reason so here is where we expect to place the system of course it will be covered in a similar boost where the drinking water valves are located and the idea is to put it here because also we see that here we have a slope here we have another slope that can be combined to the other line of septic tanks that came in the west side of the bay so this is the east side the west side and everything can be combined here so having the membrane bioreactor here it's a good point that later on can be moved somewhere here and grab the two streams of wastewater that are produced all right and almost just almost finishing we were there it was very nice but it was also very nice to to return back home so in Antarctic you have two moments that you are very happy it's the day that you arrive and the day that you depart and that is true they told us but we don't didn't believe until until that happened to us and of course getting there is not you will not go in commercial planes so you need to go in military planes so this is a plane from the air force and a Hercules plane from from the air force that is a cargo plane pretty much and yeah so we were very happy that the mission was over and we succeeded having a lot of data and information and we were hungry and very cold so it was good to to go back home all right so I would like to acknowledge first the technological university from Uruguay that provide the the place the connections to to do the research and also the the funding then also to the Antarctic Institute in Uruguay that of course they are running the the base and they allow us to to do this and also the the team that that were there particularly Beren and Alejandra from IHE and Utec side but also Richard that he was a staff from the Antarctic Institute that was also supporting supporting that all right so that's it and we are now I think open to questions thank you hope you enjoy the presentation okay okay thank you very much Hector for your great experience and presentation and I will have a tough time because there are a lot of questions and I will start just for a simple one from Vicky Ferrer and Abdullah Adam who has which are the sizes of the tanks and also yeah that is the first one and also if the tanks are line from Salah again sorry the the first the first one was is the septic tanks are line you can always also open the the chat with me and it will be easy so the first question is are the septic tanks line and what are the sizes of the tanks there you go now I guess you can hear me yes so the the sizes it depends they go between five and ten cubic meters and the the tanks are already it's not that they are built with membrane so they they already are fabricated for for that reason so that a septic tanks especially build a septic tanks so and they are put it underground they excavate and they put the tanks over there for the septic tanks can I have a information about well this is the information of the size of the components that is a little bit the the same question that we have have not connected sorry I cannot see the questions can I see the questions okay sludge is overflowing in some tanks is there any chance of pollution of the drinking water sources as it is an open source yeah so the actually the septic tanks I would say depend how big they are and how much time it's provided for for settling the sludge and there are no compartments in the tank so they are very basic it's pretty much a tank uh that is there so when the flow is little it allows enough time and there is low uh mixing so the there is enough condition for the sludge to settle and in that case the the supermate and well what it comes in the outfall of the of the tank is is relatively okay the thing is when the in particular in the summer so when there is a lot of usage of the showers and of the of the flash in the toilet the the flow that the septic tank receives too much for the volume of the tank so the mixing it's considerable and then what is coming there is not much different what is the septic tank and what is coming out of the of the septic tank so that's more or less uh how it works we have another question uh of lita is from the water quality check from the septic tank because from all domestic source come to septic tank house the results and is it contaminated the lake for drinking water quality how often people the slash yeah so the in well first question is the the lake the lake is way way upstream of the base and there is nothing there not even in the summer you know so and in winter even you know less chances for for contamination so the lake is super pristine and everything that we measured was perfectly okay so in the chilean base and the russian base they are close to the airport and the so and the lake it doesn't look that clean to the to this other lake because you know there are more people around there are planes there are wastewater treatment plants so both the chilean and russian bases they do chlorination of the water and even if the chilean base they have an arrow system for that they take only only for drinking water but they cook and they shower with chlorinated water that's the first question and the second question i forgot was on the septic tanks on the this logic this logic yeah so once a year in the summer there is a navy a boat going there where they take provisions and they take ways and also they take the the settle sludge with them the thing is that if there is a settle sludge because if the septic tanks are too little and the flow too too high the mixing is too much and there is not settled sludge right so that's why there is a lot of room for improvement there in the base thank you vector and i have another question here which is a dr alladin asks if the septic tanks are made of steel or soil or or concrete which is the material oh yeah that's i don't know if was able to see i think from the presentation there are some pictures that were were clear to see and others not that many so they they bought tanks made of plastic i think it's pbc the material they dig the floor and they put the the the tanks underground them so they are not concrete and that is what there is no lining or you know or membrane there because the the tanks were were bought already constructed and and they were put it in the they excavate and put the tanks underground a lot of time is it grabbing sampling and what's the size no is a grab is is grab sampling is another question and what is the destination of the sludge from the septic tank yeah the second we already answered so this oh destination is it it i mean we describe that the sludge is pick up by the navy and the destination is in the in the in the city in it's a base of uruguay so it's in the city in montevideo i don't know exactly but i guess it's in the some wastewater treatment plant and the yeah the procedure that we did it was we did grab samples so we didn't do a continuous sample but you know we think it's it's it could be we consider that is representative a sample what what we got yeah it's a polyethylene tank shiwon is comment on that and yeah it's right it's a polyethylene tank the material perfect and here i have another question there is a lot of sounds for your presentation and here Guillermo sinola asks in the membrane system you will have a lot of sludge how you treat it yeah that's a good question thank you so the for this system that we have we design a compartment in that pilot that that compartment is only allocated for a sludge treatment so we are wasting a sludge into that tank and then we are aerobically digesting the sludge anyways some sludge will be produced but it will be way minor compared to the the amount of waste that they are dealing today and then we were thinking another solutions like a microwave system that we are doing for for sort of drying and not incinerating but it's drying up to 90 95 solid but we are not there yet and it will be a little energy demanding they also have an incinerator at the at the base where they get rid of waste of kitchen waste or domestic waste and probably that's also a way that we could do that but it may have some environmental impact to the atmosphere I would say we will take some sludge and at the end the balance what we will be producing will be much less what compared to what is produced right now I think we should go to the last questions and it's difficult to to have them all so please I will invite you to write extra questions that cannot be addressed now to send it by email to Hector or to me they will send it to him in the membrane process this was one no yeah in the membrane process the most suitable technology process in Antarctica would other more robust less sustainable processes via a runner such as membrane and this one RBC well I think how it depends how that is seen and usually a membrane bioreactor is seen as a high-tech technology that requires a lot of maintenance and operation but based on our experience here at the institute that we work in very challenging countries and situations sometimes we find out that membrane bioreactor are less challenging than that that a conventional treatment system so I will challenge that first statement that the technology is it it requires a lot of maintenance and you know and maintenance and operation I disagree with that so it's a it's a technology indeed but but also a septic tanks to properly operate needs some attention so and I would say there is a perfect system for a decentralized context like like the one that we that we have here and and the driver is there so it's decentralized we need to produce a super high quality water for avoiding to contamination of that pristine environment and also it opens possibility for reusing the water uh not of course probably we it could be reused for drinking water if we couple the nbr with auto system and something else like some experiences that are they are doing in other countries but probably we will not go that far but it can be reused for flushing the toilet for instance and then we'll reduce considerable the the amount of water that is that is consumed and I would say rbc on mvbr could be even more challenging that that that the membrane bioreactor so I would say okay probably if we compare membrane bioreactor with a more advanced septic tank but anyways the the quality that we will get we will never the same as the water quality treated effluent that we can get on a on a membrane bioreactor and also cost there is an another misconception that membrane bioreactors are super expensive and that is that that is not correct so also price are are more and more affordable every day good thank you very much extra and our time has arrived to to the to the moment to say thank you very much to all of you to be part of these online seminar that it was extremely interesting we have been in a continent and in a region that we usually we are not informed of the situation thank you very much Hector for your presentation are being available to be with us thank you to all the participants and of course I remind you that the presentation will be is recorded and it will be sent to all the persons who have been registered and you can also see it later and find it in the youtube page of IEG Delft our next event or online seminar will be next month and we will have the pleasure to welcome a new alumni from the ones who have been graduated received their diploma last April and all will be announced in the coming weeks if you have extra questions do not hesitate to send it by us by email so I will send it to Hector and you can find all the contact details of Hector in the web page but please be informed that there has to be a hacker so the web page you will not see it in the coming days from outside the Netherlands and sorry thank you very much for your participation and willing to be with you in the next online seminar thank you very much