 Hello everyone, it's Michelle here. Richard, I think we can start already, if you are ready. Okay, thanks Michelle. Well, thanks everyone for joining us for our webinar series. This is our third supply webinar series and it's a fantastic turnout. We've got 88 people registered for this one which shows a real interest in this technology and also probably a market need for it. So today's topic is about Willowstick and how it can be used as a non-intrusive geophysical method to identify, map and model preferential groundwater flow paths. I think all the hydrogeologists in the room would agree that actually working out where groundwater flows, particularly in things like fracture sex, can be very challenging using monitoring wells and levels and that sort of thing. The Willowstick approach provides a great way of supplementing those methods to get a much clearer picture of your conceptual models. Today we're lucky, I guess just a little bit on HydroTerra before we get started, but really in terms of what we want to do with these webinar series is to generate awareness for you guys in what the technologies are that are out there and how we support those technologies in Australia to provide you with a headache-free service. It's also about passing on knowledge, so in a way it's really important that as a supplier we are educating you in the applications of these technologies. So in terms of Willowstick as a company, they've been around for 15 years and really it's one of those great sort of US success stories, a company that has developed a technology and successfully commercialised it. It's something that I think Australia is starting to wake up to and realise we need to start commercialising more of our great inventions too. But Willowstick is a really good example of that technology. This particular technology has been applied in a wide variety of settings where you need to understand subsurface flow paths. The ones we've been most involved with in Australia relate to dams and tailings dams, but there's particularly around mining, but also around traditional water storages. But it does have broader applications like you'll see on this slide in terms of in the contaminated land space and we have done some projects in Australia utilising the Willowstick approach for example mapping flow paths in fractured basalt where there was contaminant migration. Look, today we've got a really good team to present and we'd like you to have the original founder of Willowstick, Bill Coffhead to present. He's the President and Chief Operating Officer of Willowstick and he's supported by Ryan Blanchard, he's the Vice President of Business Development. Ryan's the main person we deal with on a day-to-day basis and he provides us with exceptional support. Quite a few you may have already met Ryan, he's been out on some road trips around Australia with us over the last few years. Our role is distributor of the technology and what does that mean? It means we provide logistical support to the technology and that's headed up by Adam Rogan who's a hydrogeologist with Hydrotera and really between the two of us we provide the on-ground support and logistics to make sure the measurements can be collected and Willowstick do the interpretation. Maybe in terms of questions you might have for these presenters so Val and Adam are the main presenters today, Adam will start off. If you do have any questions you just push that Q&A box on top of your screen there and type questions in there. At the end of the presentation Adam will field those questions out to Val, Ryan or myself and Adam to answer them as best we can. Next slide, thanks Michelle. Okay, so I'm going to hand over to Adam now who's going to give you an introduction to the technology and then Val's going to run through the series of case studies. So thank you very much for joining us today. Thanks Richard, it's great to be here with the Willowstick team. First I'd like to give you guys just a quick overview of the outline of the presentation. So Michelle if you could just skip to the next slide. Thank you. So what I'm looking to talk about here as Richard said before was an outline of the technology itself. So what is a typical survey layout as well as a look at the actual instrument that we use to take field measurements to conduct the survey itself. And then Val and assisted by Ryan will go and talk about a number of case studies that really show and highlight the power of this technology. And finally we'll follow up with a Q&A session as well. So Michelle if you can just go to the next slide. What are the major area of focus? Well we feel this technology fits into a number of different avenues. One being the dams, canals, levees as well as groundwater space. Definitely has applications for mining. We can get tattling dams specifically. As well as the oil and gas, environmental restoration and wastewater and water pipelines and tunnels as well. There's a number of key principles that the Willis Tech technology is based upon that are used to carry out the survey and identify these preferential flow paths. So I'd just like to outline those so you guys can understand what the technology is based upon. The first one is the idea that urban materials are poor electrical conductors. Water substantially increases the conductivity of urban materials. Both water and electricity will follow the part of lease resistance when there is a potential difference. And finally all electrical currents generate magnetic fields and the intensity of the magnetic field is proportional to the magnitude of the electrical current. Next I'll run through a typical survey layer. So using the principles that I just mentioned, this is a typical survey layout. You've got an urban dam, the dam wall, and you've got an upstream and a downstream areas. What we've got as you can see is an electrode in the upstream location as well as the downstream location. Connecting both of those is a circuit wire, which is powered through a power supply in red. You'll see there is also the Willis Tech instrument and the field person on the surface of that dam wall. And once a survey begins, you'll see there is a electric current concentrating in the seepage path between the upstream and the downstream sections through that dam wall. So because of this electric current being generated, as we just discussed, there is also a resultant magnetic field that magnetic field is represented by the green circles. What the Willis Tech instrument is looking to do is to measure the intensity of those magnetic fields on the surface. So Michelle, if you can skip to the next one. Thank you. So what we've got here is the Willis Tech instrument. So this is what we utilise in the field to take that, as I said, to measure that magnetic field. So it consists of a GPS and antenna, a portable computer which records all the field measurements, and then you've got the actual Willis Tech instrument and coils itself. And this is really the painted technology for Willis Tech. It's these highly sensitive magnetic coils that sit within the instrument itself. So Willis Tech have found or discovered a great way to miniaturise these magnetic coils. Coils of a similar sensitivity would weigh a couple of hundred pounds and normally fit in the back of a huge, for example. But the Willis Tech coil is the size of a deep battery and weighs only a few ounces. So these coils are what gives the Willis Tech technology its edge and allows it to conduct and measure the magnetic fields. In this diagram you'll see that you've got once again the electrical current in yellow and you've got the magnetic field in green. And that, as I said, what the instrument's actually measuring, that magnetic field. So from this, I'd like to hand over to Val from Willis Tech. He's going to talk about a number of different case studies and highlighting the power of technology. So Val, I'd like to hand over to you. Okay, I'm opening up my... Can you see my screen now? Yes. Okay. Well, the first case study that I'd like to talk about is a tailings dam, a seepage investigation of a tailings dam. Now, this is quite a complex project. That's why I selected it. There's a couple of things. This tailings dam was built in a number of phases. I'll go through that in just a minute, but there was a number of seeps located downstream of the dam in this particular area. Here and here and here. You can see all these little droplets. When we surveyed the site, we actually touched every place that there was a seep and those were the locations of the seeps. And the objective was, find out how seepage gets through the embankment. Not only where it occurs, but why it's occurring. Those are the kind of important questions. When I said this is kind of a complex project, this is a cross-section of the dam. You can see this tan-colored material is just the tailings and permanent materials. They had a real tight, compacted sand. They called it cyclone sand. It's very small, very compacted, almost impervious in some regards. They had a clay core in this particular area. Not specifically. I don't understand exactly the design here, but I'll talk about that in a minute. You can see this bedrock. This is competent bedrock or native soils under the ground. This was kind of the starter dam. Again, it was cyclone sand that's different than this sand. It had different zones, different lifts and so forth. And we were commissioned to find out how leakage went through this. Now, this kind of gives you a hint. I drew this up and I'll come back to this, but we found that right in this location, this is really important. This is called a pinch out point. I'll talk about it in a minute, but this is where we found the dam had leaks in several locations. And I'll come back to this drawing in a second, but what we did is kind of what Adam explained. We placed an electrode upstream or an interior to the impoundment. We placed an electrode downstream exterior to the impoundment. We buy us electrical current to flow through the ground. Remember, earth materials will not conduct electrical current. When they're dehydrated and dry, earth materials are basically insulators. They won't conduct electrical current. However, when you add water, water is the universal solvent. It gets in, it begins to precipitate out the ions, and it becomes relatively conductive. And so as we buy us electrical current to flow through the impoundment, it will take the path of least resistance, which is the water bearing zones. Now in this particular project, this is such a large dam. Now this is in feet. You can get a fill for the station and you see a scale down here. This is such a large dam that we had to do a number of electrode configurations. This is really interesting. When we first started this project, they said, oh, you cannot go out on the surface of the tailings impoundments. Too dangerous. We said, okay, so we placed an electrode we could get to just right off the shoreline right here in this particular place. And survey one was this green outline. And we buy us an electrical current to flow from the interior electrode to the exterior electrode. It was interesting when we did this survey and then we did the yellow survey. This is the second survey number two. And we showed them the results and they were really pleased. And I said, you know, I just don't think the electrode in this position is going to work very well to buy us electrical current through this study area. And so we did this red survey right here. And sure enough, it was a poor setup. In fact, the electrical current flowed to this power line right here to complete a circuit and didn't kind of concentrate in that area. And we showed them that. And we said, really, to do that, we've got to get the electrode out here. And so they said, okay, we'll help you get the electrode out there. So we placed the electrode in this place, this location, and the blue survey was performed. And it kind of, it included the red survey area. So we really did three surveys, but we demonstrated that this wasn't going to work for this area. And so, but, but I'll go into that a minute. It's really electrode position is really important. We'll get into that in just a minute. But this is the, this is survey one layout. It's a, this is the interior electrode. Here's the exterior electrode. Here's the study area as electrical current. Now this tailings material is quite conducted. It's a high. There's a lot of metals in this water. It's very conducted. And you can see these little white lines represent kind of a uniform distribution of electric current. Think of it. That water is about as homogeneous or this tailings waters as homogeneous as you can be. It spreads out in inside of that embankment and then it has to find a way through the embankment to its return electrode. Now notice, we placed the return electrode downstream, the furthest downstream of these seats right here. It's important to recognize that all of the electrical current concentrates into and out of the electrodes. So they can't be positioned in the study area, nor can the circuit wire go through the study area. The circuit wire is routed out and around the study area. All the electrical current concentrates in this circuit wire, as well as in and out of the electrodes. And we're not interested in, we know where those electrodes are positioned. We know where that circuit wires position. What we're interested in is how does the electric current, once it gets away from the two electrodes, as it propagates to them, what does it do? And how does it concentrate? And when we take measurements on the surface of the ground, all these little red plus signs that you see here, is where we take measurements. Now we carry this instrument. You saw a picture of it. It weighs about 20 pounds. We carry it from point to point. It takes about 10 seconds to take a reading and we go to the next measurement. But we cover this with thousands of readings, measurements of the magnetic field and its intensity. Then what we do is we take that data and I skipped a couple of steps in here. I'm going to show another project where I skipped a step and maybe I shouldn't have, but let me explain something to you. We predict what the distribution of electrical current would look like through the subsurface area. And it's called the predicted magnetic field. I don't have a figure of that. And then what we do, we predict it, we assume a homogeneous subsurface. Now we know the subsurface is not homogeneous and we don't expect it to be, but you'll see it becomes very apparent in just a minute why we predict, we assume the subsurface to be homogeneous. Now we take into account the topography of the site. We take into account the position of the electrodes, the circuit wire. We take into account of the conductive nature of the water and the conductive nature of the native ground and we can predict what that distribution of electrical current would be. And then we actually measure the magnetic field. And again, I don't have a picture of the magnetic field, but this ratio response map, the way this ratio response map is generated is we take the measured magnetic field and we divide it by the predicted magnetic field and what we get is a ratio. In other words, if the measured field is exactly the same as the predicted, we color it white. The ratio is one to one. However, if the electric current density is greater than one, we shade it green, meaning there's more electric current concentrating in this location than what we'd expect and where we shade it purple, there's less electrical current. Now this is really interesting. This is why I wanted to point this out. This is a very complex site. I saw this anomalous feature right here in the ratio response data. Now the ratio response is not meant to be interpreted, but it does show and indicate the distribution of electrical current. And what I found is when I started studying this and really after I inverted it and so I saw the depth, what we found is you'll note here, this is the crest of the dam. Keep in mind that these dash lines are future raises of the abatement. This area where my cursor is right now, that's the level that we were at at the time of the survey. And that was the center of the dam. And this pinch out point, you'll notice that the pinch out point is in front, or I should say downstream of the crest right in this particular area. And this is what we're seeing. We're seeing a concentration of the electric current right along that pinch out point. Now we didn't know that at the time. When we get into modeling, we'll show how we discovered that. But when I say we invert it, what the inversion program does is it determines, it predicts or estimates what the distribution of electrical current is in the subsurface to give us that ratio response that we calculated on the surface. And I can show you an example of the ratio response map. Let me pull that up. Let me get the right one here. Okay, this is the viewer. Now notice something. I can take slices, elevation slices. I can start right at the crest. There's the crest of the dam. And I can slide down through it, elevation slices. I can take cross-sectional slices. I can take longitudinal slices. And I can take this information, and I can input it into a 3D model. Now we make a 3D model of the site. The clients give us plan views. Here's a plan view of the dam. They give us cross-sectional views. They give us LiDAR. They give us the topography. They give us a lot of information. And we build a model. And this is what this particular model looks like. Let me turn a couple of, let me go to the first scene here. It's a little quicker. This is the model. Now what's interesting, I need to say something. We built this model in phases. This red shaded color, this is the first dam. I'm going to kind of call it the starter dam. And you can see the as built drawings. And you can see that the dam is raised to this point right now. In fact, I can turn, I can get in a little bit closer on this. And here's the plan view of the dam. We can put all that geo-reference into our model. Here's the crest as it sits right now. Now this is that black shade. That's the crest line right there. And this is the slope. And then, but this starter dam right here was important. And I'm going to, I'll show you out in just a minute why I broke this out the way I did and built the model the way I did. But we can take those ECD model slices that I just showed you a minute ago. If I take the ECD model viewer again, I keep grabbing the wrong, the wrong thing. I can take, I can take various slices and I can import that into the model for visualization purposes and interpretation. So you can see, you can see here that I brought that slice in and I can, I can rotate it up and I can also take and I can take cross-sectional slices. Now what's interesting about this particular project is we found that our electrical current kind of concentrated right in front of that pinch out point. And that pinch out point is right at the crest of this dam. That kind of concentrated in front of that pinch out point, but where in a butt of the hillside, there was a bed, a bedding plane right here that kind of dips. In fact, I'll show you how you can, you can see it a little bit better, not so much here, but you can see the concentration of our electric current. Green shading represents where our electrical current is more concentrated than what we'd expected to be. The purple's words less expected. And as you, as you can kind of take slice like a card deck, I can look at slices in front of another and I can kind of connect these and show you kind of the flow path through the dam. Now you can actually see that bedding plane kind of dips. This is really good as it kind of goes around the end of the abutment of that starter dam. It's in that bedding plane and it actually circumvents around the dam. So now let's go to, let's go back to my PowerPoint slides for just a second. And let's just look at some slides. I showed that, that our electric current kind of concentrated in front of the dam. Now there's a few weaknesses, there's a few areas that does go through. Now, now disregard the edges. Keep in mind that we didn't take measurement points outside the study area. And the inversion tends to see that like out here in front of the pond, it's quite conductive. It seems to kind of grow green. It's just the edge effects. You got to take that into account here. It just edge effects. The reason we don't see edge effects down here is because if I gave you a deeper slice, which I can give you a deeper slice, we have, we don't have edge effects because, because we're not at the boundary of the survey, but you have to pay attention and be careful not to, not to, you know, when you're interpreting near edges, but certainly the red arrow kind of points out where the electrical current concentrates. And this gray dashed line right here represents the approximate location of the pinch out point. This is where our electric current concentrated as it followed that seepage flow path out of the reservoir. And if I showed you this right here, now we can give you all sorts. We can give you slices. We can give you depth slices. We can give you ISO surfaces. There's lots of ways to evaluate and look at this flow path. This happens to be just a 50 foot depth slice. In other words, the slice follows the contour of the ground down at this 50 foot contour. And it kind of helpful. You can see the, the main flow path pitches right here kind of follows, it flows around the dam. I don't have the, the dam draw, the footprint of the dam, the starter dam there, but this is right at the end of it. It falls right through a bedding plane. And then what it does, it comes down here and it starts to daylight out and, and some continues to go on down the canyon. And so, you know, we can take individual slices. This is, this is, if you go back to this section AA prime, I'm taking a section right through the, through the model and in place embedded in the 3D model, but you can see the depth. In fact, I can show you, I can show you, if I take the another section, I can show you from this cross section where the, the client had elevations. I can show you the exact elevation of that pinch out point, that pinch out point occurs about right here. You can see the concentration of that flow path, right in here where it's the darkest green. And then it's going, it's going around the abutment. So it goes where the circle is, it's going into the page. And where this arrow comes out, it's coming back out of the page. It kind of goes around there and that, and that's the, that, that's the downstream abut, but you can start to identify and characterize the seepage full pass. Now I described to you how seepage, we found a seepage path that went around kind of the starter dam and it's contributing to this seepage right here. We did find some other seepage flow paths. Now this is a, another depth splice. It's a little bit deeper. This is a little bit deeper section of the dam, but notice right here that we have kind of a weakness across the, what I call the crest of that starter dam. You can see purple shading here. Now we got edge effects and edge effects. Be careful, but you got purple shading here, purple shading to this kind of a weak area where it's flowing through that pinch out point or falls towards that pinch out point. And then right here is the pinched out. This is the pinch out point and water comes down and it hits this point. It kind of bifurcates around this hill. Some of it comes down into here and some of it comes down into here. And I can take sections again, this CC prime. This is kind of interesting. This, this CC prime, we're looking upstream through the dam. This is the elevation of the pinch out point right there. And you see that electrical current concentrate there and concentrate right to there. Now notice this, you see, you see evidence of this as vertical chimney. Remember when I was, when I showed you this flow path on the backside of this clay core right here, they put a vertical chimney and then kind of a chimney, a blanket, a drain blanket down here. And our electrical current comes through there and drops right down that chimney blanket. And now watch this. I got to get to the right. I've showed you those slides already. This is that, this is that concentration and then it's flowing down in the chimney blanket. Now, I'm going to give you a section here that's, that's CC prime. Now. This was CC prime. Now what I'm going to do in this next view is I'm going to, I'm going to pay attention to where C prime is located. I'm going to go around the backside of it. Now this is the back. This is CC prime right there. Instead of looking upstream, I'm kind of looking downstream now through it. And the reason I, I chose this cross-sectional slide. It was the closest cross-section to our seat location. And you'll know that the right here is the pinch out point. And I drew a line right over to here. That's the pinch out point. And then the vertical drain, the vertical chimney sits right in here and that's, that's the vertical chimney. And then it starts to flow down in the drain blanket. And it gets a little bit weaker. But in the next slide, I think it shows up really good. Now this is another section and another little bit of location, but you certainly see that vertical chimney right here. Now again, remember this is the, you're not looking at the crest of the, the finished dam. You're looking at the crest of the starter dam. And what's happening is that seepage kind of flows through that pinch out point that's right here. It goes down the vertical chimney drain and then drains out down here towards the toe of the dam. And in the bottom line to summarize this investigation, what we did is we were able to identify the primary seepage flow paths and these yellows are the secondary. These are inferred, these thicker dash yellow lines are kind of inferred, but it's important we were able to give them coordinates. This point one, two, three, four, five, six. These are coordinates that the client wanted to have to to prove these, these locations in 0.6 and seven, eight, nine. I didn't provide the coordinates for you because of, I told the client that I wouldn't expose the site. Now that's another case study here. I'm going to move along kind of quickly because I've got more information to cover here. This is a mind pit investigation. We had a, we had a client, a large mining company. They had a, a pit. I'm on the East, East wall here. They had seepage coming through the hillside and they, they had a hard time characterizing it. They put several wells upstream. You can see one, two, three, four. I've seen, I've seen projects where they've been, had over a hundred wells and not being able to identify the seepage flow paths. And then they have a number of wells down a little bit lower and they're trying to characterize this flow path. It's a difficult time. And they called and said, can you characterize? We said, certainly. So we placed an electrode here upstream in a well in contact with the groundwater regime. We placed an electrode down here, the lowest part of the pit in another well that's completed in, in, in, in the groundwater regime. And we buy us electrical current. Now notice these little yellow lines represent the uniform distribution of electrical current kind of in a homogenous assumed condition. We have our circle wire that goes out and around the steady area. We don't want it to be the dominant signal. We want the current is flowing through the ground and we take measurements on the surface of the ground to be the dominant signal. Now note, we could only take measurements on the benches to steep and dangerous any, any place else. So we just took measurements on the, on the, on the benches. And here's this, here's just a, you know, a typical cross-section. We've got our upgrading electrode. We have our downgrading electrode. You kind of see that we're placing that electrode. So it's in the, the seat location, the seat manifestation is kind of in the barrel of the gun, so to speak. We buy us our electrical current through it. Now this is why I skipped before, and I should have shown you this before. This is the predicted magnetic field. Now think of it as kind of like throwing a rock into a pond. The current, the magnetic field, radiate out uniformly from the, the upgrading electrode. Then it, then it kind of uniforms out. And then it goes back down to the lower electrode, but it's kind of got a uniform flow. That's the predicted field. Then we have our measured field. This is the actual measured field. Now it looks similar to the predicted field and it should. This is a hard rock. It's relatively homogeneous. It has some heterogeneity to it. And we're going to bring that out. And the way we bring that heterogeneity out is we take this observed magnetic field or the measured magnetic field. We divide it by the predicted magnetic field. And we get a ratio response map. The ratio, meaning that the words green shaded, the electric current is more concentrated than we'd expect it. And the purple words less. Now again, just looking at the ratio response map, I can see a flow path that's, that's coming from the North down and not, and not from the East. Now when we inverted the data, we run it through our inversion and then we, we build a model of the site. Now these are contours and, and LiDAR and wells, depths and locations and all that. We put all the information that they could have on their site into our models. And then we insert our ECD model slices. Now what you're looking at here is a series of East West oriented vertical ECD model slices. And you can really start to see the flow path. As it comes down to the purple shading is where electrical current isn't getting. And you can see this purple shading up here, an electrode I think is in, I can't remember one of these well, one of these two wells here. But as it comes out of there, it hurries and concentrates in that groundwater flow path and shows us the flow path as it infiltrates the pit. And it's up here to the North and not, and not to where they thought it was. Now this is another, this is a series of elevation slices. You can see how well that flow path shows up right here. If I turn this elevation slice on and turned others, you'd see the flow path a little bit better. Also, I can make an iso surface of that flow path. An iso surface is just an electric, an equally electrical potential zone, I guess, in the ground. And it just highlights that flow path and kind of a three dimensional aspect. I can also take a section. I can take like a cross section. This CC is cutting through the, through the seepage flow path. And you can see here that I think that this is a potential fracture zone in that hard rock. This is a great, you know, mine companies should use this technology to help identify these weaknesses and these flow paths. I'll show you another technology that's really good at this too in just a second. But the bottom line is we help this client understand how water infiltrates their pit. Now, this next, I've got to hurry along here to get through. This is very interesting. This is a well side and study. This is in Idaho Springs, Idaho. This is in the United States. Idaho is in the western part of the United States. They had a spring. It's called Formation Spring and it produces about 3,000 gallons per minute. It flows up out of the ground. And the community of soda springs, they are around about 2,500 and then the surrounding community has probably another 1,500, 2,000 people. So a population of about 4,000-5,000 people. This spring supplies both culinary water and irrigation water. Well, the Department of Environmental Quality, the drinking water department, came along and they condemned this spring. And the reason they condemned it is because when they took water samples of it, they found animal and plant coal form in the water and they deemed it, you know, not safe to drink. And the water is just kind of burbling up in this little bit of a pond reservoir and then they capture it and take it to town. Well, birds and animals and plants and things like that were polluting the water. And so they said, look, you're going to have to treat the water. And so all the engineers in the western United States heard about this. They ran into this job and they wanted to build a microfiltration treatment plant at the cost of about $12 to $15 million is what the estimated cost was. And then they would supply all the water to both culinary and irrigation. And the other choice they had is they could just treat a little bit of water, build like a $2 or $3 million treatment plant for their culinary needs. But that would require them to build a distribution to another distribution system, one for their irrigation and one for their culinary water at a tune of about another $20 to $30 million. And they said that we're just not going to do that. And so they contacted me and they said, can you find this water source? Can you find where that water is coming up from depth? And you have to find it at 200 feet away from the source and at 100 feet below the ground surface. That's a pretty tall order. You've got all this real estate that you've got to investigate to find out where that water is. But we said, yeah, we can do it. And so what we did is we placed an electrode in contact with the spring. There's some farmhouses up over here. There was a well that was in contact with the groundwater and there was a little bit over there. We energized different directions. And what we found is we found an anomaly right here at 210 feet away from the spring. It's just amazing. Now here, this is an isosurface. And what this is, where my cursor is right here, this is the range front fault. And we believe that the range front fault acts as a barrier. And in other words, it's not as acting as a conduit. It's acting as a barrier and forcing as the water comes, migrates down, it hits this barrier and forces the water to the surface and it flows up here. So we placed a well right in this particular area. And what was interesting is that when they drilled this well, I can tell you a little history about it. This is well number one. They drilled this well right here and they got down to about 170 feet and they drilled it with a six inch well. And it produced about, oh, it produced about six, no, 400 gallons per minute out of that six inch well. That well was at capacity. And they said, we hit the mother low. And so we said, oh, great, congratulations. And so they, they reamed this, this well out to an 18 inch diameter well. And they test pumped it and they broke suction at about 600 gallons per minute, a far cry from the 3000 gallons per minute that they were hoping for. And so they said, what do we do? And they said, should we drill deeper? And I said, well, I can't guarantee going deeper is going to do anything and ignore this map right here. Just ignore this map. This is a different map. And so what they did is they decided to experiment around, they went and drilled another well here and they got a couple hundred gallons per minute artesian. They went down here. I don't know what they were doing when they thought to drill their way out of bounds. And then they drilled another well here, got a couple of hundred gallons per minute. And so they decided to go deeper and they took this well down to 450 feet about and they, and they hit another supply of water that increased this well to about 25, 2600 gallons per minute artesian flow. And so they were pretty satisfied with that, but they didn't get as much as what's flowing out of here. And so we came back and we said, you know, we're interested. We've developed a couple of more techniques that we want to demonstrate to you and to our clients, you guys especially. And so one is called the gamma survey. Gamma is known. It's not proprietary to us, but the earth emits gamma rays. And one of the things that the block the gamma rays are water. And so we did a gamma survey and you can see we got this kind of this shadow footprint, this dark blue is where our gamma dropped significantly. Now that doesn't mean that that's where the water is coming up from depth or anything. It could be coming up and spreading out. We didn't quite know what to kind of think of that, but it was kind of interesting that that gamma survey showed us that. But then we did a technique that's called ramps or wraps. It's called wrap rapid acoustic profiling. And it's a technique that's unique to us. We weren't the inventors of it, but we're, we're, we're, we got a close relationship to the inventor. And what it does is it's, it listens to the movement of the earth. People don't realize that the earth is like a, is like a big water balloon. It's continually stretching and moving with the planetary motions around the earth and so forth. And it creates residents. It creates, as the rock rubs against each other, it creates residents and you can determine where you have weak rock or where you have competent rock. And what was interesting is this is an isosurface of that ramp investigation. Now what's interesting is when we drilled down to hear about the 170 feet, we got a lot of water. And then they got out of it and they developed that, didn't have enough water. So they eventually did go deeper and down here, they encountered another significant amount of water. But what was interesting is the wrap showed a real weak joint right in here. And we think if we'd have moved that well over there to have a lot more water, probably may not have had to go as deep to intercept that fracture. But nonetheless, this was a very successful project. And the reason I share this with you is because you've got a means to kind of at several layers, I should say, or several different, totally different techniques that you can apply to a site to help you understand and characterize the groundwater flow. Now I'm going to really cut it short here. This is a, this is this fourth case study that I've got is called a compare investigation. And a compare survey is just a repeat survey. Now this was a dam that we did in Germany in, in 2015. And in this particular investigation in 2015, we found a seepage flow path around the north abutment, right in, right at the north abutment contact. And, and we recommended that they, they put a grout curtain to cut it off. And they came in here with a grout curtain. And this is the grout curtain that they installed, but it was really interesting to us. That's not where we told them to put the grout curtain. We told them to put the grout curtain here. This is, this is a copy right out of the recommended report. And I inserted their, their grout curtain. And I said to him on the phone, they called me and they said, Hey, you know, we did this. We did what you told us to do, but we still got seepage. We've cut a lot of it out, but we still got a lot of seepage. And so I said, well, show me what you did. So we, we took their data, their grat data and we placed it in the map. And I said, well, look, you didn't, you didn't go far enough. We expect the seepage to flow around your grout curtain. And they said, can you prove that? And I said, certainly. And the way we could prove that is we did a repeat survey. We put an electrode upstream, exactly in the location we did on the original survey. We put an electrode downstream, exactly in the position we did in the original survey. We put the circuit wire in the exact same position. We took measurements in the exact same location. Within centimeters of where we took it. And this is a difference. This map is called a difference map. And you see up here in this graph, the difference. Remember the law of continuity. If we energized this site exactly the way we did it, if we put in a grout curtain and there's less, less electrical curtain going through this area now, which shaded blue, because there's less electrical current in the difference map. However, where the red is, we have increased electric current flow. And notice this, we said, look, it's, it's, it's plain as day. The electric, you didn't bring this curtain far enough into this tighter formation here. And so what you've got is you've got electrical current that flows around, that flows around your, your sheet pile wall. And they had since gone and grouted this and remediated like 95% of the seepage. So now in summary, I've kind of gone five minutes over my time, but in summary, I just want to summarize this, you know, traditional will stick investigations are used to locate, model and predict subsurface water flow paths and patterns in three dimensions for a variety of applications and geologic settings. I noticed when Adam gave his opening presentation, he said the will stick has done over 300 investigations. Well, that's a few years ago today. Actually we're more, we're near 400 major, major water investigations throughout the world for some of the most sophisticated clientele and engineers, dam owners in the world. And, and we, and, and 80% of those clients have had us back for repeat business. So if it doesn't work, we would have flushed it out by now. Then I just want to point out that a will stick compare investigation. That's a really interesting that effectively adds a fourth dimension by considering the temporal effects of an investigation. You know, for example, in many cases, the need to see the trend of changes taking place over time is more significant than the need to understand a precise model of the way things exist today. And we find that's true. We've worked with mining companies. They kind of get a base map and then they go in and do a lot of mining. We come back periodically and we see the trend of changes in how they're impacting the environment. We see that the same thing we've done dams that have leaks when the water level is high and then low. We survey when it's low, we survey when it's high and we actually see the trend, the change, very educational and very powerful tool. Well, that's my end of my, my presentation and I've used up my time. I appreciate your attendance. And so I'll turn it back over to Adam. Thanks, Val. Thank you very much for that. So now I guess I'd like to open it up to questions. We've got a couple of questions already, but I'd just like to remind participants that there's a Q&A box at the toolbar at the bottom of the Zoom screen. And if they could put in their questions regarding this technology, I'm more than happy to answer them now. But I'll start off with the first two questions. I'll just read them out and then we can talk to those. So the first question is the cost of the realistic surveys is higher compared to other geophysical techniques. And sometimes it's hard to justify clients. It would help if you could provide some justification for the higher costs, i.e., is it mainly processing time. So potentially Val, maybe you could go into a bit of detail in respect to the processing as well as the time that you guys take to bring up the models and things like that. And we can also talk about the field time as well, because that's a significant component. You know, Adam, let me just say, was that the first question? Have you ever had any failed projects? Is that the question? That was the second question. Yeah, that was the first one was just the. We've had some, I don't know if they've failed. There's been projects where we may have not answered all of the client's questions and problems, but one time we did a project. I did not know this, but there's places in this world where groundwater does not have ions. And if the water is not ionized some way. Now, I'm talking about, I'm not talking about drinking water quality. We can do surveys with as low as 100 microseconds per centimeter of conductivity, very, very low, very clean, very high quality water. But there are waters that don't have any ions in them. And we could, if you can't get a circuit to flow through the ground, you cannot, you cannot do an investigation. And so, and so it's important that and also to, and for example, I've had a few projects where we've put electrodes down a well, come to find out the wells plug. There's no preparations. We can't get electrical current to flow. You've got to be able to bias the electrical current through the ground. If you do that electrical current doesn't lie. It takes the path of least resistance. That's a fact. And we can measure its distribution and flow through the ground out of probably those 400 projects that we've done. I can only think of two or three that we weren't successfully able to complete because of, you know, no ions or kind of just not being able to get a circuit, real unusual kind of a setup, but we found those things early in the project and we were able to just go to the client say, Hey, we can't get it to work. And we reduced the cost of the investigation. Beautiful. Val, the other question that he had for you was just the cost seems to be higher than other geophysical techniques. Do you want to kind of just speak to that? Well, I can say this much, you know, it would be great to do a whole seminar on our webinar on the return on investment with the will of stick investigation. I can't that you, you can't, you can't, you wouldn't believe how many projects I've gone where they've used every geophysical technique you can think of. They've drilled wells and we've come in and set up and been able to define what the problem is and how water's moving and confirm, confirm that. And, and I, you know, the will stick technique, the return on investment is usually, you know, real impressive compared to other geophysical techniques that may be a little bit more expensive than like traditional resistivity, but it's a lot more powerful. And it doesn't replace well drilling or anything. I don't want to give you the impression of that. But what it does say, tell you it tells you where to start focusing your remediation efforts or your monitoring efforts or your, you know, ground truthing efforts. And it's always been a cost effective approach. I'll just add to that that it's not necessarily in processing time and it's not necessarily in field work time. It's probably the cost might be a little more because of the 3D modeling and all of the additional consulting services that we spend a lot of time on, on conference calls with the client. We add a lot into our 3D modeling. And I think other geophysics techniques don't spend as much time in that consulting services and 3D modeling. So I think that's where you have a justification in, in our, our technique being a little bit more expensive. Beautiful. Thank you. Brian Val. The next question. How does ballistic handle things like landfill contents? I with lots of metal items, et cetera. Well, let me, let me answer this way. Landfill contents don't really have a major effect. For example, remember, we're placing electrode at point A, we're placing electrode at point B, and the electrical current is being influenced by things that are helping complete the circuit. Now, if I have a barrel or a still cased well, that's just a vertical well, it really doesn't help complete the circuit. It's just a, it's just a six or eight inch well or four inch well or two inch metal well or a four foot barrel. It doesn't really help complete the circuit from point A to point B. Remember, we play, we place these electrodes thousands of feet, I mean, meters that, you know, three, 400, 900 meters apart. And that little bit of debris doesn't really help complete the circuit. What the electrical current does, it gets out in the water bearing zones, they're long continuous conductors. Now, if you have a, if you had a metal feature that was long conductor, like a railroad track, like a fence line, and you placed your electrodes so that it became the path of least resistance, then your electrical current would get on that. When we go to a site, we asked the client to give us all of the conductive culture. When I mean by conductive cultures, any man made feature that's metal, that's a long continuous conductor, pipelines, power lines, fences, railroad tracks. And when we, when we map those out, we set up the surveys to have minimum, minimal impacts on the survey. But at the same time too, we can model some of those effects out or simply we take those into account when we're interpreting the data. So they are problematic, but again, I could show you lots of projects for Denson. There's been a lot of conductive culture and been able to set up a survey that, that gives us the kind of answer that we're looking for. Fantastic. The next question. If you had a utility pit, i.e. sewer stormwater, would you also be able to follow the groundwater flow outside of that utility, trying to work out if the contaminated groundwater is migrating? Yeah, if you had a stormwater or sewer stormwater pit or whatever, you put electrode inside of it, you put an electrode downstream. Again, you kind of want to focus your electric current to flow down the barrel of the gun. You want to kind of flow it downstream. You look at the topography or you look at water levels and some modern wells. You aim your current and it will take the path. It'll identify the water bearing zone, the flow path. Perfect. If you have applied this technology to landfills to characterize lead shape flow paths within and beyond the landfill. Yeah, in fact, you have a, you know, you prepared this slide show originally and we had a project that we did for a large, it was a brownfield, whatever you call it. It's a government site that they took over a big landfill leachate flowing away from this site. Very neat. They've made papers written on it. We've done that on several occasions, mapping leachate out of landfills. So, yes, it's an application that we can do. What are the common limitations to the project? There's a couple of it. What are the basic data needed from the client and do you supply 3D outputs of models to clients and how do you package this? So, maybe we'll just start off with the first one in regards to the common limitations to the project. I'm going to answer the first question. What are the common limitations to the project? You know, again, we have to, I don't like to place the electrodes much over two or three kilometers apart, preferably, you know, like a kilometer, maybe half a kilometer or something like that. I don't like to get them too close. We can put them within, you know, 50 meters or something like that, but you're biasing the electric current strongly through the ground. What we're interested is, again, get those electrodes out, kind of way far apart from each other, and then as the current flows out into the ground, it'll just naturally start to concentrate in the paths of least resistance. You know, so the size is sometimes, again, if the project area we're doing is so large, and that was a great example of that first project I showed you, we divide the steady area into smaller steady areas and investigate it and then kind of piece it together so we have one large survey. Also, if we have a lot of conducted culture, I mean, if you were in a steel yard or something like that, there may be too much conductive culture on top of the ground where our electrical current wouldn't get in the ground. One thing, people say, how deep can you go and things like that? Well, if you can't bias the electrical current at depth, it's very difficult. I mean, if you only have electrodes on the surface, your electrical current is going to concentrate at the surface. We've done projects like for Chevron where we're down 1800 feet, but they have wells to get our electrodes down there. So we've been very successful at those kind of depths. But there are limitations, and those are the ones on the top of my head. Ryan, do you want to answer what are the basic that they need? Yes, absolutely. So we send and Hydrotera helps us when a client is interested at no cost to you. Oh, good, and Adam's even pulled it up. We give you a pre-proposal checklist and you can see there's three columns there. And we really need the first column. So that information required for a proposal, you know, the location of the site, the map with area of interest delineated, and then that description of the site and groundwater situation. And then we also like to understand what is expected of Willis-Dick in the investigation. Now there's other two other columns that really help us hone in on our understanding and on in our proposal and cost estimate. Sometimes we don't get that information until after we've been on site and we've been contracted with the client. And that's fine too. But we really, we really, before we actually go mobilize, we like to get the conductive culture, the utility map, all the metal. We like to understand well logs, any sinkholes, ponds or anything like that as well. So that kind of gives you a list of the information that we have, that we'd like to get. And the final one was the 3D output of the models. So how is this packaged to send to clients? Yeah, regarding the 3D output, we have, we use, oh, and I can't remember Val. Do you remember the name of it? That's Google Sketchup. Sketchup, yes. We use Sketchup, but we can put it in a format for our clients. If they have a 3D model that they use like LeapFrog or there's, there's other 3D models. We can provide you with the raw data to put into your 3D model. And we're happy to give that to you. And then give you kind of a training course on what to look at like Val mentioned about edge effects and that stuff so that, so that when you put it into your 3D model, you understand what you're looking at. But the other thing that we do when clients don't have a 3D model is we just provide you with a scene. Val was showing you some of the scenes on some of those, on some of those case studies. And we'll also provide that to our client where, where they can go in and look at each scene and each, each different area that they want to really hone in on and, and understand and characterize. The next question. Does the realistic method determine groundwater seepage rights, or is it a spatial distribution only? It's a, it's a spatial distribution only. We have, we have done some work with. You know, when you do a mod flow type of a. Modeling traditional model where you have to predict what the. Hydraulic conductivity is we, we've actually, if the, if the client has wells in and knows the hydraulic conductivity and we've surveyed the area, we can, we can correlate or maybe the right word is not correlate. Maybe it's a calibrate. The water model to be a little bit better where the, where we have zones of higher effective prostate and we have lower effective prostate and we, we've had some good results with that, although we're not a traditional groundwater model experts in that, in that regard. And we need to work with the engineers that, that are. Are there health and safety issues associated with electricity and does this present a roadblock to implementing this technology across some sites? Well, there's electric current in that wire, but the electrical current, it's just really interesting. The, the voltage we use is less than 300 volts. Normally it's around, I'm going to say 100, 150 volts. The amperage is only two amps, two amps is just enough, maybe to light a light bulb. And so, you know, it's like any appliance that you have, you treat it with respect, you know, you don't stick your fingers into plugs and things like that. We also have what's called the circuit fault interrupter on our circuit. If somebody comes in contact and we're to break that circuit or change the flow of electrical current, we energize the ground at 380 hertz. And the reason that we use 380 hertz, it's not a harmonic of your 60 or your 50 cycle that's prevalent through the world. And if that current in that circle wire is interrupted by 380 of a second, it shuts the circuit down. So it's even quicker than your, your GFI is that you have on your homes in your bathrooms. So we take precaution, but no, we're not dealing with large voltages and amperages. And it's, it's relatively safe. We've been doing it for 15 years and haven't had any accidents. I just add to that. Also, we also engage with the clients to and, and go through the full H&S procedure. We send through all the documentation and make sure that everyone is aware prior to conducting the field work of the health and safety measures that need to be put in place to ensure as what Val said, that nothing does occur and that we're on top of that. If anything does come up as it does in field work. Next question. Is the method able to differentiate between saturated clays and saturated sand would both be similarly highly conductive, but flow regime very different? You know, yeah, the answer to that is yes, it can differentiate between saturated sands and saturated clays. They have different porosities. And again, the electrical current will concentrate where it has the least path, but a lot of people are hung up on wet clays. You know, we've been taught in textbooks that wet clays are super conductive. Well, they are conductive, but I've got some experimental information that I could share that if you had, if you had wet clays, it'd be conductive, but if you had free flowing water in wet clays, they would be more conductive. And so that's probably another seminar for another day. But the simple answer here is yes, we can't differentiate between saturated clays and sands. Can will those stick map induced stream bed infiltration due to quarry pit dewatering? I'm not sure induced stream bed infiltration. You mean if you're watering a pit and the stream began to dry up, could we determine that? There's some coal mines that I work with back in the eastern part of the United States where they have, there's a law. If you start mining underground and you disrupt the surface flow, they have to restore that stream flow. And we've placed electrodes down in wells deep down into the mine and then we put them in the streams and we survey along the streams to see where that electrical current stops flowing down the stream and starts to flow down into the earth. And we've been successful at identifying where they are dewatering these streams and they go back in and do a grout program and restore the flow to the streams. I'm not sure I'm answering that question, but that's the experience we've had. Can these investigations be undertaken close to power lines or power stations? Yes. As I told you, we energize at 380 hertz, which is not harmonic if you're 50 or you're 60 hertz cycle. We could be riding under a power line. We don't care. That 50 hertz or that 60 hertz is filled it out. We are listening to our heartbreak beat, which is 380 hertz. It's not harmonic. We can do it right under power lines. Can you identify difference between water quality such as saline and freshwater interface? Yeah, we've done some investigations with saltwater intrusion. Now, if you were talking to me about a chemical, for example, you had a contaminant that's in the water, I don't think that changes the conductivity enough. It has to be like an order of magnitude. Now, saltwater is probably an order of magnitude more conductive than regular water. And when we energize from a saltwater source to a freshwater source, you see the change in conductivity in the ground, especially along the preferential flow paths. Beautiful. Well, that looks like that's the end of... Sorry, just another question popped up. My question about power lines was due to the magnetic field created by them, not the electrical risk. Again, the magnetic field has the same characteristics as the electric field. In other words, if you're energizing at a certain frequency, a 50 Hertz frequency, the magnetic field has a 50 Hertz frequency. We're filtering those frequencies out. So the magnetic field doesn't have any... Now, if you were within a foot or two of the power line, it would probably interfere. But if you stayed 50 feet away from it, you know, and again, that's important to know where all these are. When we plan to lay out the surveys, we know what we're dealing with and we survey around those or we survey right on them and we actually locate where those power lines are and the influence that they're having on the survey and we can actually model them out. Beautiful. That looks like that's the final question. Okay. Adam, I might just say a couple of words to wrap up. No worries, Richard. So thanks very much to our speakers today, particularly Val, who's been the lion's share of the work today. I'm sure people found his wisdom very valuable. The experience we've had with Willowstick over the years that we've been the distributor here in Australia has been very positive. I think the highest success rate that they achieve on individual projects relates to a couple of factors. One, obviously a huge amount of experience doing a lot of similar projects and I think that's what in part differentiates them from the other geophysical techniques that are out there as they've managed to really fine-tune their methodology for groundwater more than anyone else in the world. The second thing is they are actually very careful at the front end of the project and we've had some opportunities here in Australia where the decision has been made that Willowstick is not the right technology to use in a particular application. So that in itself increases the chances of success overall because you're being very careful what to take on. So we found it a very positive experience working with Willowstick. In terms of once the project starts, we've worked on several projects with Willowstick now. If the data is not showing up, they continue to change the electrode configuration to give themselves the best possible chance. Sometimes we've done three or four different configurations on the one project to get that data. So I think very thorough on the job, very thorough selecting the jobs they take on and a huge amount of experience all lead to a positive outcome for the clients. So thanks very much to everyone presenting here today and hope you enjoy the rest of your days. Cheers.