 Hello everyone here. Welcome. Hello everyone who's on the internet and I'm sure more people will be coming from both directions. This is an event that is sponsored by the friend of our which is a nonprofit volunteer group. The mission is to protect, conserve, and restore, remediate the Pine Street Barge Canal, which is just down the street. In fact, we are part of, this land is part of the Superfund site that the Pine Street Barge Canal is also part of. My name is Andy Simon. Andy, can you move a little bit to your, my name is Andy Simon and we part of our work at the Barge Canal is cleaning up the garbage that's been there for decades. Part of it is really getting people to learn about the Barge Canal because so many people have spent their whole life at Burlington and never set foot on the Barge Canal. They've gone by on the bike path and gone by on Pine Street. Everybody tells me I've never been there. So we've been trying to do events that also help beautify and clean up and restore the Pine Street Barge Canal, this wild space in the south end of Burlington. But at the same time, our other goal is to bring people to the Barge Canal, give people an opportunity to get to know that land, beautiful land better. One of the ways we're doing that is by inviting Dr. Graham Bradley today to talk about what's beneath the Barge Canal, specifically geology and hydrogeology of this interesting area. I've got to know Graham through his work as our regulator for the Department of Environmental Conservation. During the public hearing last October in this very room, I noticed that beside being a regulator and being a hydrogeologist, Graham was a teacher. So I asked him to exercise that part of his expertise and come and do this. I'm very glad you accepted. Maybe I just wanted to give a quick acknowledgement of this land, that the land that we are on is unseated Amnaki land and the Amnaki have cared for this land for 10,000 years and are still present on the land. And it's good for us to remember that we are there on the land that was never ceded to us. So that's important. Thank you, Graham. Go ahead. And you see where you've got to stand so I don't mind. So which of the other people are looking at this one. Yeah. So, I need to look that way. No, I'm just saying you need to stand in the center somewhere. We'll be putting the slides on soon and I'll probably disappear. Thank you for the introduction. I'm really grateful for friends of mine now for inviting me along today and it's given me an opportunity to look a little closely more closely at the geological history of this site. It's difficult to know where to pitch my talk so I will try and gauge that as we go along. I may have wanted to. Too many slides so I may end up skipping one or two. I'll keep an eye on the clock and maybe about an hour and a half in this room. Hopefully I can keep it well into an hour of time for questions. If I am, if I'm saying something that is really someone doesn't understand, I'm happy for people to, it might be a little difficult for people online. If anyone in the room wants to ask a question as I go along, I'm happy to take questions that actually helps me know how to gauge the talk and where to set it. So, yeah, if you want to bring up the first slide. Sure, let's get to the screen share set up again. Okay. So, while you're doing that. I'll just tell you a bit about my background you can tell, I've got an English accent. I've moved. I moved to Oswego, central New York to work at the State University of New York there. 2012 working in the Department of Geology was there for about five years, six years. We fell in love with them on the trail, spending all that time over here. So in the end, I ended up moving over here and got a job with Department of Environmental Conservation. Prior to working at SUNY Oswego, I worked the 17 years with a consulting company, groundwater specialist hydrogeology, working in the UK, but also in Vancouver and Canada as well. And then I have what I call my midlife crisis went off and did a PhD, which was actually in Uganda. Looking at the evolution of the landscape in Uganda and the influence of that on groundwater resources, groundwater resources in Uganda. Okay, and that brings us to the first slide. So, I am the site manager on behalf of the state. We oversee what EPA do, make sure the state agrees with it on super fun sites. And I'm also the brand fields manager for 453 pound, pine streets as well, but I'm taking off my regulator hat tonight. Okay, so I won't be answering any specific regulation questions. I'm a geologist tonight and a groundwater specialist. And they asked me to talk about the hydrogeology because he knows that's what I'm involved with professionally. Actually, the main focus of my talk is on the geological history tonight. But I tried to add in some hydrogeology to understand the groundwater flow, the hydrogeology you have to understand the geology as well. And I will say that, you know, I haven't done the investigations at this site. I haven't done the research at this site. I am presenting work done by Ben, Ben, other people. I'm Ben Maynard. He was involved with the Johnson Company and the original site investigation to super fun sites. And I'm using some of his images and friends with Stephen Wright and George Springston to well known local geologists that work on the glacial deposits and river deposits in Vermont. And then Hugo, my colleague. Some of you may know, and he did a lot of work on maps in Burlington and discover, rediscover this ravine that goes through the middle of Burlington as well. By the way, I live in Plainfield, so I'm not totally familiar with all of the streets and then the vicinity. The module logical survey my colleagues there and then some of the consultants that have worked on the sidestone environmental Western and Samson I've already mentioned Johnson Company, which I've now involved it taken over by VHP work there, VHP, EPA, DC, and thousands of other researchers that universities and BFD students, etc. piece together the geology of Vermont over time. So it's just going to work. What I need to do. Thank you guys next slide. Just looking at what you're speaking about me. Sorry, my mouth is a bit dry. I'm going to talk in a while. This is just, we're going to come back to this. This is just an indication of how we know about the geology under our feet. Barge canal. This is actually sort of a section for those at home. I'm pointing at the screen. On the right hand side there. And I'm hoping to explain that as we go along. Each of those colored vertical lines there is a borehole that's being put down through the different geological layers using a drilling rig like this. And all of those young cytologists on site logging the soils that were brought up, and they're able to unlock the characteristics of those to help us understand how the groundwater flows and understand how they were formed, what environment they were formed in. Because we can use that to piece together the different layers, correlate between boreholes and understand the geological history of the site. And I'm focusing on that geological history. So next, there we go. Okay, so this is a diagram taken from a 1999 report by Don Maynard, and I'm kind of using this as the basis of my talk. I'm not expecting to understand this slide now, but hopefully by the end of tonight, you will have a better understanding of it. This are all the different layers one on top of another going back down to the bedrock. These are just approximate depths to give you an idea, scale that we're talking about, and 150 feet, it varies across the site, bedrock, and then we've got other layers at 60 feet, 20, 10, and then we've got the ground surface up there. And we're going to go through it starting at the bottom of the rock, 500 million years old. And that won't be the necessary the focus of this talk but I'm going to tell you a little bit about that the bedrock right at the bottom of the pile. And we'll be coming up through the pile to sediments deposited in a glacial lake during the last glaciation, the last ice age, around 13 to 12,000 years ago. Then we'll have kind of, it's a bit of a spoiler here for those of you who don't know it's kind of an exciting part of the talk. We've got marine deposits under there, about 12 to 10,000 years old, and that fits in nicely with what you were saying about the first peoples here. And it's not my specialty to understand that there's evidence of the first peoples as the ice sheets receded around that shoreline. And we've got lake Champlain. I know we've got archaeologists in the room so call out if I'm getting that wrong. Now we start to get some to something that's a little bit more familiar. So this is post ice age, I can't put 5,000, less than 5,000, it might be only a thousand. But to a geologist, that's, that's a pick of the fingers, a thousand years. So we're getting much more recent, and you might be able to sort of start to pick out some of the features that you can kind of vaguely make out on the maps around the 5th Street barge canal. And then we get up to the last 200 years, when we've got Burlington Roy, and the barge canal, the looming infield, and the industrial development on site. So that's what I'm talking about today. And as I said, hopefully by the end of the talk, you'll understand a bit more about that. It's a geological succession. So I'm going to start with the bed locker. And, yeah, it's been all, I'm trying to use the computer into your slides if you just want to say next or something. Okay, well, it's a little awkward because I've got some animations in my hands. So what am I doing is just put it on the chair. Let's see if that works. These are some of the slides I might end up missing. How do I go backwards? Come out and go back in. Back out. Back out of my room. There we go. Okay. So that geological succession I had, I'm right down at the bottom of it, the bedrock 140 feet down, 100 to 140 feet down. Beneath where you're standing, you've stood in the woods there on the trail at the canal. And what we've got there is a rock called Moncton Quartzite, predominantly made of quartz. It's the same rocks as at Red Rocks Park. I haven't been there. I really want to go. I have to go there. And given the fossils that are in that rock, we know it's kind of 500 million years old during what geologists called Cambrian period, which was when there was the explosion of complex multi-cellular life. And some of the oldest sort of complex organisms on earth there at this age, 500 million years old. And there's other features in these rocks. Ripple marks. And see these are sedimentary rocks, the positives are water. And the tridentite fossils, worm burrows, raindrop in France. So do you think this was deep water or shallow water? It's got raindrops. Yeah, so deposited in relatively shallow water. See if it's working now. Now this is the slide that I wondered whether I should even bother with this. I'm going to go through 500 million years in a couple of minutes. Here's your 200 million years ago to 500 million years ago. Here's your mountain formation. These are all the names that geologists give these different periods. Above this is the Jurassic. So everyone's on the Jurassic Park. And the mountain formation here, it's on the edge of this continent down here. And all I really want to get out of this. What I want to explain is why we have glacial sediments sat straight on top of the bedrock. What's happened in between. These are, these are less than 20,000 years old. These are 500 million years old. Where's the missing history. 500 million years missing. What happened during that time, there was three different collisions, global collisions, mountain building events against the original continent here. I don't have time to play tectonics, you know, I can talk more afterwards if you like. So we had a volcanic island arc similar to Japan and crashing into Laurentia. When I say crashing at the speed of your fingernails grow. Then we had this microcontinent also came piloting into Laurentia. This microcontinent geologists give it the name. Avalonia. What do you associate with Avalon? Jersey Shore. That's a new one of me. Avalon is an old name for England. And actually England was is at the northern part of that micro continent. So at this point, my country was crashing was part of North America. I'm going to go quick. Finally, Africa crashed into North America or Baltic others. Geologists call it that. And so we have this huge area here through the green mountains and the northern part of North America. And we have a lot of population mountains where we have we've had several collisions against the edge of North America. So we have these huge mountains here the size of the Himalayas. And over time, and we're still only at 300 million years old here. We've got another 300 million years and over that time they have eroded and then to East the Atlantic Ocean opened up. So this is why we have this is where this missing piece went. We've got 500 million years missing here. And it's essentially it's because these old mountains are eroded down really what geologists call an unconfirmity. The only thing I want you to get out of here is this is the geology of the mountain and overall those bedrock layers are all north south. And that's because we've got these three different collisions into this this ancient continent and we're up here in Burlington and we're on these these sediments here that were originally deposited on the edge of of Laurentia. So that's that's the bedrock geology very quickly. It's not really what I thought want to focus on today. I thought it was good to point out why we've why what's happened to that missing history. And then we've got glacial sediments deposited deposited by glacier. So right on top there, deposited during what we call the Wisconsin glaciation. And the height of that ice age was around about. There has been many glaciations over the last of again how long over a million year last million years. Coming and going at the most recent one reached its height about 25,000 years ago. When an ice sheet covered the whole of the month. It didn't quite look like this out for a photo online that might represent ice sheets, because actually most of the mountains in Vermont. There's no evidence that they poked out. The ice was a long way above that Mansfield. It was actually higher than that. So, you know, we're starting to get to a point where basically the rock of the month is formed. And there is a proto sort of Champlain Valley here with a glacier going down it in a road by the ice. So I can now stand in this room and imagine myself under this ice sheet. With several kilometers, several miles of ice on top of me now. 20,000 years ago. So this is showing kind of the maximum extent of that ice sheet. And I've picked out the outline of the month there. Okay, so what did that leave us behind? What's under Pine Street, right at the bottom of the pile here just on top of the bedrock. At least saddens and growls. Because we know that they're smoothed and rounded. They have had some that been washed and rolled around in the meltwater from that glacier. So the ice sheet started to recede. You started to get more and more meltwater and it's carrying the sediment with it that it's eroded in the bedrock. And you start to have water on top of the glacier and under the glacier. And then when that melts, it's left that kind of in depressions in the bedrock at the base. The debris that was carried by the ice itself. There isn't really any evidence of that, what we call till, there isn't any evidence of that. At the bottom of that pile in Pine Street, there's just these, what I call glacial fluvial, positive by the water in the ice, right at the bottom. So the glacier scoured the rock, left it clean. And then those rivers in the glacier left that sand and gravel behind. So we started building up. To build up that geological succession. Okay. And so the ice continues to recede. Here's the outline of the bont again. We're now at around about 13,000 years ago. And we start to get lengths developed and then dammed by the by the ice meltwater coming off the ice. And there's lakes forming in front of the ice there. It's not quite right. This is showing the outlines of the modern lakes. Actually the lake in the area of Lake Ontario Lake. They're quite the geologists have named it was actually bigger than that. You can imagine a lot more water coming down. It's down by the ice. It's a lot bigger. But we do have this lake here. And it's not yet like Champlain call it Lake Vermont. It is dammed by the ice sheet. And the water is starting to melt. It's starting to go off the ice. And it's creating a lake. There's actually other lakes. There's a lake in the Connecticut Valley called Lake Hitchcock as well. Okay. So we have Lake Vermont. What was Lake Vermont left us? Did I skip a slide? Go to previous. There we go. Just check. I got. Okay. So here is that kind of overview of glacial Lake Vermont. I said you've got to imagine as the ice is retreating from the ice. This lake grows in size. And I've actually, we've sat there. So now. Again, this is what we do as geologists. This is what bring me on about geology in the first place. That looking at the soils and the rock beneath my feet. I was it when I was a teenager. It's big. I could actually look at the middle earth that existed here where I'm standing now. And that's what I'm thinking about now. I'm stood here. And there's hundreds of feet of cold glacial lake above my head, above all of our heads. Okay. If you were here. 13,000 years ago. I was a teenager. I was a teenager. I was a teenager. I was a teenager. I was a teenager. I was a teenager. I was a teenager. I was a teenager. I was a teenager. I was a teenager. I was a teenager. I was a teenager. I was a teenager. I was a teenager. I was a teenager. I was a teenager. And what we did, 11,000 years ago, you'd be pretty cold. You'd be pretty deep in the water as well. Okay, you can actually look at this for yourselves. If you Google natural resource act less. line geographical information system GIS and there's a load of boxes on the left-hand side and you can play around with those layers, turn them on and off and there's just loads in fascinating information. You want to look at cities, you've got the property boundaries, the roads, etc, that turn all those off. I can turn on the geology, I can turn on the extent of the glacial lakes as well, so I downloaded this from that website, Natural Resource Atlas. So what did that leave behind? Oh and there's an image of what you might see, this is a smaller lake than Lake Vermont but it's a glacial lake to give that impression of the ice retreating. So now we've added several tens of feet onto that geological succession under Pine Street that was all deposited in that glacial lake that was hundreds of feet above our head and it's deposited something called, well different layers, varved silts and clays, fine layers of silts and clays. So what do I mean by varves? And this is one of the pieces of evidence that we know this is glacial lake seven. What happens is, during the summer, the temperature warms up, the glacier starts melting, some of that sediment, that sand is washed off into the lake in front of the glacier and that sand, it's a larger particle, it's heavy, it falls to the bottom, bracing those tens of feet of lake sediments. But during the winter, what happens during the winter? What happens to lake shumpling? Same happens to that lake in front of the ice sheet. That gives a chance and then it's very quiet and nice. That gives a chance for the finer layers of silts and clays to fall to the bottom. This happens year after year after year or how long did I say the lake existed? Yeah, thousand years, thousand years and it builds up over time. So this is an actual photograph. I forget which lake it's taken from. My presentation I do have, I haven't quoted names. I've tried to reference the pages where I've got these images from. This is from a different lake, a different part of Vermont where we still see these these varved clays alternating fine and coarse sediment. So we don't see that throughout the course on the pine streets but I understand that they have seen it in some locations. So it was that seasonal deposition in a place of lake. Any questions? So Graham, some of the boring instead of being done at times people might look like that. They're probably not quite as nice as a good example as far as that but I understand that they have seen fars. They're actually able to use this for dating, looking very detailed and counting back. Okay, what happens next? Yeah, yeah. So about, it might be a little later, earlier. About a 12, 11,500 years ago, the ice sheet has made its way back into what we now know as Quebec and this ice sheet, it was so heavy that it actually pushed the crust of the earth down a little. So under that ice the ground was actually lower than it is today. So when this ice sheet started to recede it was able to, it led in the ocean in the St. Lawrence Valley, Gulf of St. Lawrence. The ocean was able to come in and it actually came in all the way up into the Champlain Valley and those in the room who are more familiar with the indigenous history, the first peoples of this area understand this evidence around 11,000 years associated with the shoreline of this ancient and so that that times that's very nice because it kind of, you know, at the same time humans people were moving northwards in Europe, they were also moving northwards in North America as the ice receded and making use of that land that was opening up but the ice sheet receded around Lake Champlain there. Okay, so now we've added another sequence to our cause under Pine Street. So now one of my objectives this evening is just, you know, trying to give you a glimpse of how a geologist looks at the world. When I will go out to, you know, I walked last tonight before I came here and I was looking at the trees and the current environment and on a beautiful day like today it was lovely to see but as a geologist I'm also looking at other features in the landscape that point to this hidden history below our feet as well at the canal. So you can see here it came all the way into into Quebec. I've actually my first job five years ago with a contrast to being a professor I was working in the Leechfield program looking for teaching soil descriptions to leechfield designers and engineers and I was working up a south hero where they were digging holes to see if it was suitable soils for for a leechfield for a septic system and seashells, clear as day, bivalves, mollusks, layers and layers will fit in here. That's from the Champlain Seed. That's the evidence we have of that Champlain Seed. Is there anyone else? Is there anyone else who was found evidence of a the sea or a lot? Why are you not? Charlotte? Yeah, that's it. Thanks. I'm glad I'm I'm glad others are aware of this as well. And again you're probably I've known about this for a lot longer than I have. When I I guled this I didn't realize it was found in in Charlotte. This is the this is the whale. It's a beluga. I've tried to keep for the photo on this present a photo for each of these environments what it would look like today. So you can imagine yourself in a boat back there on the Champlain Seed in this area that became Vermont watching the belugas in the sea like that. That's with camel something like that. Was the sea salty? Yes, yeah, it's salt water. The whale interestingly and this will come back to our story a little later. They found it while constructing the railroad between Rutland and Burlington in 1849. I think it was about 10 feet down. Okay, so very obvious evidence. You know belugas don't live in but you can probably you go digging the right place. You might not be looking enough to find a whale skeleton but there's a number of places where it's pretty easy to find those seashells. I wonder if they knew what they found. I don't have to be in the railroad workers did but there's articles online. It's now I believe it's in the museum either. Yeah, I'm excited. I want to go see that. Does anyone see? Yeah, yeah, it's cool. Right, so then this is taken from the Natural Resource Atlas. It's still got the lake on but what they've done to show the sea Champlain Seed so the unhatched area is actually dry and dry land by the time it's invaded by the sea. We're here again, Pine Street Canal inside that yellow circle. It's a little small to see but there's actually an island, an unhatched area. That was an island but just east of us and might be able to see that on some maps that show in a moment. I'm not quite sure the name of the streets. So the sea level is a little shallow. 100 feet or something above our heads right now. So after the ice receded but we're now under the water and there's well swimming around. Okay, so I have to remember I'm not giving a talk to my university students but I think it's good to try and understand why is it fresh water now? Why is it a lake now? Why isn't it still the sea? Remember I said that the ice sheet pushed the land down the way to the ice pushes the earth to press down. Well after the ice is all gone or it's retreated back that way it's gone and the land bounces back. So now Quebec comes up and the Champlain Sea recedes the coastline recedes back to its current site position leaving Lake Champlain in the Champlain Valley high and dry. Now you've still got all those rivers and things flowing into it so eventually it becomes fresh water. Well that's the lake we have today. Initially it was a little, let me see, the level of the lake is partly determined by that rebound there and stopping it flowing out that way. Now one point it was actually quite higher than it is today and I'll show you that old shoreline. So what was the edge of the Champlain Sea was once horizontal of course, lakes and oceans are flat, water finds its level but when we look for evidence of where the edge of that sea was now it's sloping and that's our evidence that the land to the north is bounced back. So that makes sense. Good. Okay, I originally had this later in the talk. I thought it was good to put it in here and it just reminds us where we are. So we have a modern-day map, large canal here, super fun site in this area, 453 Pine Street in here, moving back here's Pine Street itself. You're probably more familiar with the streets than I am. What is this area? Is this a school? Is it UVM playing fields up there? Yes. Okay, well UVM playing fields up on the hill there. You know I mentioned there was an island in the Champlain Sea, they were on that island. Okay. If you were back there 11,000 years ago you'd have had to get a boat out. But when we look at the geology there that's where we get, we do get some glacial sediments but we also get some beach sediments from the edge of the Champlain Sea there. Here we have our marine clays here that would be put in that lake Vermont. Lake Champlain is a lot lower than the Champlain Sea. We're still not at the current shoreline this is still higher than the current shoreline and I just took a walk along. So if I stand in front of the barge canal 453 and peer through the buildings there's a steep slope along behind these buildings here. Do you know what I'm talking about? Yeah. And that was an old shoreline there, back there. So these are the actual geological layers. So initially the edge of Champlain, Lake Champlain was the other side of Pine Street was an old shoreline here and you can see that in the topography as well. So what we're going to move on to do is, so we're, I got a bit enthusiastic with this plan to help everybody set. Okay we're going to get on to some of the things that we're more familiar with in terms of the recent sediments and they've been looked at in a lot more detail. They influenced the hydrogeology, the groundwater flow beneath the current site a lot more. Those were actually deposited in a lagoon beside Lake Champlain when it was at a lower level down there. Okay, so that's moving from Lake Champlain Sea to Lake Champlain. So what was the shoreline like? The original shoreline before the 1800s, before the industrial development. Rhetorical question. How do we know what that shoreline was like, the original shoreline? Well, when I look up again using the natural resource atlas, all of the natural soil maps are on there. Fortunately at this zoomed out scale it doesn't tell you what the different soil types are. If I zoomed in I could click on these and it would tell me what all the different soil types are. But in looking at this I noticed all of this area which I've highlighted in orange is human made soil. It's filled. All of that. And you can see the shading under fill here. That's actually the current wetlands. So you've got this now looking at the right hand image. I've taken the shape of that fill and put it on top of what we call a lidar image. It's like radar, except it uses lasers. Basically it bounces, it can fly over with a plane. You fire lasers at the ground and it can detect how long it takes to get back to the plane, the airplane. And from that it knows how far it's traveled until you can build up this release map with all the hills and valleys. And so that's what we're showing here. And when I pulled this up and looked at this, one of two people said they've heard of this ravine and you can actually still see that on the lidar. So if you know where to look when you go towards Main Street, College Street is it, know which buildings to look out for. You can see there's a depression in the ground and it's being kind of built to practice. And this was a channel. They still exist to this day on the other side, on the Winooski side. So it would have been a feature similar to these other ones on the north side, on the Winooski side. That channel flowed down into this lagoon here. As it originally was, into Lakeshark Plain at that time, so I called the name Blue, to show the original shoreline. And if you walk along as I did just before I came today, walk along Pine Street, look to the east, you can see that shoreline. You see that steep slope that goes up. So we're sat in the lagoon right now. Okay, we've got our feet wet. We're in different times during the history of that. We may have been under water, the sandy, silty bottom. And other times there was a lot of vegetation in there, sphagnum moss, and the lagoon vegetation. That's where sat down here now within that new area. So everything comes together. The salt laps, the liner image, sure, where that old shoreline was. So why did they build that extra land? This is where we get into the history, maybe a little into industry like old. It was because of the lumber, right, this photograph I found online. I may be getting ahead of myself here. Of course, if you see those old images of the mounds behind the capital building, no trees. Trees in Vermont were cut down, people were trying to farm cheap before the trees came back. Both the maples for them and the other landscape we know today. But also they were importing lumber from Canada. It was coming down. The big driver from that was the, I understand that just, if there's people who know more about this in this room than me, feel free to speak out. It was the building of the Champlain Canal to get that processed timber to the south where it was needed. I understand Burlington became the third largest lumber processing port in the country, coming from Canada, coming from Vermont. And they're not able to drag it up the hill of the shoreline and process it there. So they filled it in, including the area around the Biostreet Canal. But we'll come back to that. Let's go back to the maps. So now we're starting to get into human history or how should I put it? Record it as opposed to archaeology history. And this is my colleague Google that found these maps. We've got a map here from 1830. And I was really pleased when I saw this. It's Pine Street on there. Can you see it? It's called something different. Yeah, yeah. And it's before the canal. This is not the canal. This is the lagoon once it's all started to fill in with natural stones and natural vegetation, wetlands, becoming a wetland, more of a wetland area than the deep lagoon in here. 1830, 1849, what happened in 1849? Railroad, exactly in the way of 1849. Another way of getting that lumber out, lumber industry is expanding even more. So by 1872, they filled in this area. Still this wetland area here. Oops, what happened there? Just still this wetland area to the south. But now you can see they've turned what was a natural wetland area into the canal for the barges to get that lumber in and out. Okay. Sorry, I was probably standing on the screen. Every time you could have talked in you really have to figure out where to stand. Okay. So that's when it went through that transition from a natural lagoon to this fell area. And you can see this is, so I don't believe anyone in Vermont knew about this. Hugo found it in the lower coastal survey of Lake Vermont for navigation purposes, but it shows the contours. We've got Pine Street growing now, heading south, still a little bit of filling to do here to move Pine Streets further south. You can see these contours here around the original side of the site. Oh, different ways of showing it. This map is not really to scale. So I could kind of put it on top of the modern blocks here, but I had to stretch it a little bit to make it fit south there. You can see the ravine here very clearly on this map. You can see the old Lagoon shoreline. You can see where the open water was at that time before the canal was built. What makes it a Lagoon? I'll get to that. Okay. I'll get to that. Good question. And just I hope people might be interested to see these maps to try and picture, compare what it's like now to be before all that filling. So I put that area, that original coastline on the image there. So you can see where that original coastline was. And all of that is all of that human-made fill, unmade fill, as we used to say. That's probably what's in that area there for the lumber industry. We claim for the lumber industry. And here it is on the Lidar image. So that's a kind of fun one to look at because you can see that old shoreline matches up. I'll walk on there. You can see the shoreline. You can see where it suddenly goes up behind the buildings there. So everything you stood on, west of that, is filled. That's an incredible amount. I'm not sure where it came from. There's some sawdust, but most of it is silt and clay. It's a good point. Most of it's silt and clay, soil from somewhere. Okay. So we've added the top bit, the sands in the lagoon, and the peat, the organic material. And I looked around for what might... What was the arrow? How do I move the arrow? Okay. I looked around for what might be an analogous environment today to give you an idea of what it might have looked like. A little idea. It's not perfect, but a little idea of what it might have looked like today. This is on the shoreline of eastern Lake Ontario. We don't really have an analogous environment that I could find. Not a very good one. The areas of world lagoons, I think, in lunch, take shumplane of cities, and it's naturally filled, and now wetlands beside. So even this has started to fill up. But the several examples of the evolution of this on the side of eastern Lake Ontario, when I was in Oswego, we took geophysics equipment looking at the structure beneath these sandy deposits, this bar here along the edge of these lagoons. So when we look at the environment around the Pine Street Canal, today, beautiful environment, but essentially it's a constructed environment, and nature is taking over, getting around the canal. But originally it was a different kind of environment on the top there. I'm enthusiastic. I'm taking a little long, but we're starting to get there. We're getting near the top of the column. The way it formed, geomorphologists talk about something called long shore drift. Basically we've got sand on the lake shore and the wind in the waves. I'm not going to go into it. It's the wind in the waves is pushing it down the lake door. When it gets to a bay, like that area that I'm calling the lagoon, the sand doesn't go into the bay. It begins to cross the bay. It keeps moving down and forms this, what we call a spit, sand spit, or barrier spit. We might sometimes call it this, if it's under water at some point, if I call it a barrier, ah, my northern English accent came out. Certain vowel sounds. So this is what we had. We originally had a bay. We had the sand moving down the lake shore. It created a bar across the bay here. That's where the railway line is now. They used it. They built on it. The railroad. I keep saying railway. It's my way of saying railroad. And when it gets blocked off, you're asking me about a lagoon. I'm talking about when basically that bar, that spit crosses the bay, or might just leave a little entrance in that area behind the Coler Lagoon. Meanwhile, you have the ravine still bringing sediment down the river there, filling it with little deltas and sand on the shoreline in there. So naturally, this would fill in. But yeah, they decided to help it along, lumber industry. That makes sense. Okay. So just another quick look at that. Now provided the explanation. I don't have an area. I should have an aerial photograph. I'm speaking now from the same direction. You can imagine the railway going along this filled in, the original shoreline, which you can still see. So we're at the final lag, the fill. And now some of you may be familiar with this particularly interesting part of the street. I'm sure you've seen this image before. In the mid 1800s, the lumber industry here, there's this slipway in here where they brought the barges into. This building is where 453 Pine Street is now in the open area with the gates and the fence, the turning basin. And that's sitting on top of this orange material up here. Now, I don't think I wrote it on the slides, but yeah, there's a lot. I have to check. I know there's some of the people who did the investigation watching this, so I don't think it went wrong. But there's seltz and plays. There is some solace in there. But it wasn't documented. Okay. They don't have a really good handle on what's in there. Whatever they could found, mainly soils, though, not just all sortist, so that they could have this lumbering and build on it, the processing factories, the mill. Okay. I don't remember what slides I got. Oh, here's another one. So these are published in black and white online. And I used a little program to colour this presentation to see if we can relate to them a little better. It's not perfect colouring. Here it is up at College Street, is it? Where they haven't quite filled in this river, this ravine, this river channel. And that is Pearl Street. Pearl Street. Okay. Yeah. And then down in the distance there, you can see the lumber yards by there. By the length. This ravine, before anything, was built here. It was a river channel, and it was discharging Sandy Delta into that lagoon at the bottom there. Was that ravine the mouth of the Winooski, or was that? No, probably a much smaller channel. Yeah. Now, Winooski's way to the north. Cabin. Well, the source is in Cabin, and then it falls on it. Sure. Yeah, it goes to Plains. Yeah. Now you're tempted me to talk about the lakes that filled that valley, Lake Winooski. That's another story. Another place to lay. So, Graham, you're saying that barrier bar closed off the lagoon in the wetlands before they built the railroad? We know from our boreholes and the geology that when you drill down, you'll see in a moment, middle of Pine Street, you've got the peat underneath it from the lagoon, underneath where the railroad road is, there's sand. It just fits very nicely with what we see elsewhere in terms of this speck of sandy bar coming down from the railroad road built on top. When the ravine was filled, where did the water go? Groundwater. Yeah, it's probably still there on the ground. Unless they filled it with clay, I'm not familiar, but it's probably built still. It just takes the ground waters, it runs on the ground. Good question. Yeah. So here's a map from 1936 now. And here's the thing that caused a lot of problems, Burlington Light and Power Company. This is the old gas manufacturing plant. Back in that time, they were starting to use town gas, as I would call it. We use natural gas today, methane, which they put directly out of the ground, generally find it above. Sometimes it's by itself, it's migrated deep down in the ground. Sometimes it's associated with oil deposits. Back in that time, they used coal, mining the coal. And there's a process of heating the coal without oxygen that releases that gas, and that's what they used to burn when you think of the old movies, gas on gas. Yeah, exactly. So that's what they were burning there. A by-product is coal time. It's thick, gooey material that they had some uses for, but they had a lot of waste. And it looks like what they did, they basically just dumped it out the back. So I went into the wetlands here, this is 36, into the canal, into the slip area that was still there at the time. And over time, the soft, gooey ooze sediment, natural sediment laid on top. And that coal time is heavy. It's actually heavier than water. Sometimes, I'm not going to get into the regulatory stuff here, but we sometimes call it non-aqueous-phase liquid, which means it doesn't mix with water. And it's dense non-aqueous-phase liquid, de-napple. I remember when someone first used that phrase to me, and one of these apples, they told me, D-N-A-P-L, de-napple, dense non-aqueous-phase liquid. That's the coal time. It's dense with the water. It made its way down through that fill, and basically was soaked up by that peat from the lagoon. It's not all the way through it. I'm going to show you an image, where it is. And I hope everyone, not too exhausted, I'm taking a long time. We need it there. So that's where we are now. I think I've got an image. Next, here we go. I'm sure you're interested in how most people have seen this one before. Again, to kind of make it more accessible, I tried to colourize it a little bit. And here we have the manufactured gas plant down here. Actually, I'm wondering, early in the 1950s. Oh, yes. I'm not going to bother trying to change it now. I'm sure I'll miss it if I try and change it now. 1950s. Well spotted. Thank you. It's nice to know I'm holding your attention. Okay, so now it's starting to look much more like it does today. But so those old problematic industries are still there. Multi-text buildings there. I believe at one point this was kind of a brush manufacturing, whistles. And then you've got the manufacturer and gas plant. It was there until 1966. I remember that. That's the year I was born. Okay. And then we've got the canal over here. Big pool of goodness knows what here. That's where the coal tire seeped into the ground. Okay, now for a fun bit. McDonald Morrissey have been putting together a cross sections of the geology on behalf of stone environmental. Mike Mobile came up with this little animation. So I may play this a couple of times. So you're going to see how they put together all of that borehole information, put the layers together. Under the site. And let's hope my Wi-Fi's up to it. I think I showed it a couple of times. There's all the boreholes. Put this together. There's the bedrock down below. I'm actually going to play this again. It's a cool animation. You look at this. Here's four different cross sections of different places. This one's just south of 453. We can see all the different layers. The green layer. Well, first of all, bedrock. Right at the bottom, the black. They haven't differentiated between the lake Vermont, sultan clays, and the marine sultan clays from the Champlain Sea. Little difference in character. Generally sultan clays are pretty low permeability. But on top of that, we've got the old beach deposits here. East of Pine Street. We've got the green organic piece. Can you see a little bowl in there? That's that lagoon that appears when you start to hunch holes from it. Put the balls together. The whole story comes together. And you are asking about the barrier bar in the railroad built on top. So we do have this natural sand up there as well. So you see this change in geology across the sites. Beach, sort of organic barrier bar. On top of the peat, there's some more sultan clays that were washed in as well into that lagoon. And then the orange, if that is human made film. But they built the lumber industry on top of. So it comes together in each of the sections. Let us play to the end. And that's what lies beneath your feet. And you've got a couple more slides. Where's the tarp? I've got a slide to show that. Shall I show this one more time? Okay, one more time and I will get to the tarp. Bedrock, glacial lake, like Champlain, sorry Champlain sea, like Champlain human made film. That's what geologists see. Geologists, one of our skills is kind of visual spatial, trying to imagine and treating everything looks like just from putting the one dimensional holes in the ground. And with the ledges on there. Okay. So we were asking about the tarp. Well, first of all, let me just explain what we're looking at here. This was done a few years ago when they were originally looking at building on 453 Pine Street here. This is looking towards the east of 453 Pine Street. We've got 501 Pine Street to your right. The front of this cross section sort of coming out the screen, I'd be stood kind of where the canal is here. And then heading east, we have this slit where they brought the barges in with the lumber. We've got the silts and plays, marine and glacial lake deposits underneath. I try to use some of our color schemes. We've got the green for those organic material of peats that were in the lagoon. We do have areas with wood chips that you mentioned over here. So you can imagine as they started to fill, maybe they'd already filled the shoreline further north. And they were just dumping their wood chips over the top. And then they decided we need more land. So then they filled the rest with soil. And a new lumber yard and a new mill opened. And then in the early 1900s, 1908, the coal gas manufacturing plant opened here. And they were just discarding their waste, coal tar. That made its way down through the fill. And most of it came to a stop in the peat. It's like a sponge, just salted up. And so there does seem to be some spots where it made it a little bit deeper. But you see here in the in the slip, peat below that slip area, there's a lobe of coal tar coming out there. And then there's a lobe to the western side of 501, not the street side, but the western side of 501. In that area there. And I'll just mention this while I'm going along. When I was growing up in my grandparents' bathroom, you know what I'm going to say. They used coal tar soap or carbonic soap. It's actually what this thing is doing when you're first disinfecting operating fields, carbonic soap. And with all the bugs, it works as a disinfectant that way, but it's also toxic to us. So it's not what we use as disinfectants these days, but one of the products that they did use a coal tar for, coal tar soap. This, it says established 1860, about when they first started manufacturing coal gas, but it actually says with coal gas fragrance. Probably not. So they are actually trying to reproduce that all the time. I looked for coal tar soap. I noticed it does say it's coal tar. Sorry, everyone watching at home. You'll leave it on now. Yes. Well, I think that it's fairly recently that in certain fees used to have a product that was great for poison ivy, but they don't make it. I see coal tar. So what depths are we looking at the peat, say from south to north across those four channels? I've got a section at the end that will remind me. I think it's, it varies. Just remember, you've got a shoreline here and it kind of gets deeper into the middle. The fill on top, they only filled what was necessary. You know, it's already kind of a wetland. It's almost land surface, but they put 10, 12 feet fill on top, but it's below that. The peat, again, it goes from zero maximum at, I don't remember exactly, that kind of scale, a kind of scale. So the question was, will the demand for the coal gas, was it electricity or kerosene? What's the amount of those? Well, that's a question for anyone who's better at history than I. I can take a guess, but it's probably as good as yours, electricity. And then eventually in the sixties, we started using natural gas directly from the deposits. So, yeah, anyone know when, well, the plant posed in 66. So I've been using it, by the way, I don't know, I'm surprised. Yeah. The same company that was manufacturing the gas would also generate electricity. Oh, we're playing both hands. Yeah. I was recently at a health and safety training. And, in fact, I came out now, but you know, there's this kind of image of people, kind of a cycle, I'm not sure I should end with this. The whole gas was poisonous. How people would do themselves, but with the head of the other, methane came along, that's not poisonous. You can die of asphyxiation, it does no matter. It's not poisonous. Yeah. The whole gas. People start killing themselves by putting them in their heads. Let's move on. Hydrogeology. It's the history, the geological history that I'm really talking about. The hydrogeology is my job. But Andy did ask me a little bit about the hydrogeology. So I've blown up that section. And so here again, you can see the map. I've blown it up so it's a little bit blurred. Barge canal in here and now I've kind of made it the same length. There's a section under here. So you can see the little dip here where the barge canal is. You can see the slope behind these houses. Does anyone know what this building is? Okay, right. Behind that, you look up behind that building, you can see the slope, the original shoreline. And here's that here, with the beach. And then you get the lagoon deposit starting in here, across the Superfund site, the peat, this sort of, these silt and clays, which were deposited on top of the peat. And then that all that orange, that bit, and then some pine streets sat on top of that and then on top of the sands to the east of the site. And I've just, I haven't looked in all the local laws for the actual depth of the water table, but just to give an impression, we have that if you dig down, drill down in here, you will get to groundwater. And everything below that is saturated in groundwater. If you, if you drill down and you don't get groundwater flowing in your hole, it's not because it's not there, it's just because it's happening so slowly. It's low permeability. You dig down and you hit a sandy layer, it'll flow in quickly. It'll flow in and it'll come up to the level of the water table in there. So what happens is, this is mainly silt and clays, these old Champlain Sea, the old Vermont Lake, because it's, they're not particularly permeable. There will be some water flowing through that, but most of the flow is coming through those sands. So we have the rain falling on the land, falling in these backyards over here, infiltrating down through the soil into the sands. In some places we've got the roof of the building there, it's running off. That's got to go somewhere. So I'm not sure if that's going into the ground or if it's going into the drains directly into Lake Champlain. That's running off in some parts. We've probably got more runoff up here because it's directly on top of those silt and clays. Here it's on top of the, the yards are on sands. There's probably more water going down to the water table through there. And then flowing under the site, generally that water table is just in the bottom of that fill. That kind of makes sense if you think about it. You know, it was, there was the lagoon, the wetlands there that weren't able to put their lumber on there. So they built it up above what was the original water level in that lagoon, in that wetland, so they could build on it. So now the water level is still the same, probably not too far different to what it was in the lagoon. But now instead of being open water at wetland, it's in the bottom of the fill. Okay, so that's where it is now. And as I said, we have what we have water infiltrating the ground, flowing through the sands, from it flowing through the various deposits, some of it just at the base of the fill. Heat is an unusual material, but it's very porous. It's got a lot of space, but water finds it a little bit more difficult to travel through than it would a sands. Porous but not as permeable. It's a virus material. But anyway, there will be some water flow through there. Remember that, and that soaked up the coal tarp as well, which is down there below. Is the coal tarp below the groundwater flow? It is below the groundwater level. It is within the pit, which is otherwise saturated with groundwater. So let me just remind myself, good. So that's the story. I'm happy to answer more questions. So hopefully this is a bit more meaningful to you now. All of those borders, all of those maps, all of our knowledge of the geological history, we're able to build that column of material beneath the site, beneath that pit, the story beneath that pit. And if you go down to the bedrock, 500 million years, big gap. As we got that movement of the continents and the erosion of the glaciers, then we get Lake Vermont and those farved silt sanctuaries, Lake Vermont. Ice retreats. We have Champlain Sea coming in. We have people, indigenous people, first people arriving. And we have wetlands in that sea. Ice continues receding. The land, what we now call Canada, bounces back. And the sea goes back to its current coastline. And we get Lake Champlain. And we get this original lagoon in here. And then we get the built originally from the lumber industry. And then the 1900s, the manufactured gas plant on there. So I hope you enjoy the story. Thank you. Are there questions in the room? Or online? Yes, I'm remembering people discussing building on Pine Street. I think it's 453 because it's the lower part. They can't build one. But lots of people thought, oh, buddy, we can build. They would do designs. And then generally, they would go to see what, whether they could build it. And as I recall, people discussing it, they said 80 feet of sawdust and then you have bedrock. But it looks like what you've now found, maybe this is sometimes 10 years ago, what you found is it's not sawdust. And bedrock is really more like 140 feet, is that right? But different of those different types of sawdust. So there is a peat layer in there. Right. The organic team, there is spots of where they found sawdust before most of it was built. But generally 453 and 501, there's not big thickness of sawdust from there. There's what? There isn't big thicknesses of sawdust. Right. But there's soil or whatever it is until about 90 feet, 120 feet or something. Correct. Yeah. And so to build, they really have to put something all the way down the bedrock. Yeah, that's, so I don't. Just they're not allowed to. They're looking at that now. Right. Ways of building in that area. I don't really want to get into that. So, you know, the whole developers are looking at that, consultants are looking at that. Yes, I know that. That I'm just. Yeah. Just asking. Thank you. Sure. One thing is to mention, I'm playing in the sixth largest lake in the country, compared to the far great lakes, the glaciers in that area melt faster. That's why there's more water there. That's the right question. It's always one of what I'm wondering if I was doubting for. I'm wondering if I can easily pull up. I won't pull up the slide. If you can remember that slide is that the ice sheet was receding. Lake Vermont. And then I showed it said, it only showed the modern lakes. And I said geologists call this bigger lake, Lake Urquay. Well, that's the back of that. Tell me if I'm not. As the ice sheet continued back, it got around Platsburg and the north of the other index. Lake Urquay was at a higher level. And there are rocks up there that are scoured. What actually happened that Dan between Lake Champlain and Lake Urquay kind of melted away? Lake Urquay was higher and there was a huge flood. There's evidence that the rocks around there were scoured as the level of Lake Urquay came down as it discharged into Lake Vermont. I just had a small question when you were explaining the silt clay accumulation during the glacial period. The difference between winter and summer. And I forgot which was better, summer, the coarser material. In the winter, the finer material, would that have been accumulating actually all during the year? And it was just the addition of the coarser material? Good question. I'm getting into details. Well, what happens if the water is moving around during the summer? There's more water in the lakes we've been in. There's thermal currents in there. The really fine place may be in suspension. And it just needs very quiet conditions beneath the frozen lake for a very fine temperature to settle out. Graham, I'm still interested in the fill. And because you've changed my ideas about what the fill consisted of, but I'm curious to know why they would have brought in so much soil that was silky and clay in particular. Was that just because that's the soil that was available? And Ken, just the follow up question to that, if someone were interested, could they identify where that soil came from? So you're testing my knowledge here. I've got a lot of background, and I'll just use that to try and answer the question, but I don't know the specifics. Ask those specific questions. In terms of using soil that we now describe as silky clay, silty, I think the sand material I haven't got. It's a mixture of stuff. What's available, but they also needed something that they could build on. Of course, I'm just going to say it. So they couldn't have had 10, 15 feet of soil. That is, I don't know where they got it from, and we identify where they got it from. We've got a great comment in the chat. Here we go. Basement excavation. Oh, okay. The right person to answer. So this is Dan Boyden. Hi, Dan. He's the lead consultant with Stone Environmental, and he's saying the film likely came from basement excavations, because basement residences were moving. Oh, interesting. Thanks, Todd. Sorry. Ask a friend. When you were talking about how a lagoon can be formed, I was thinking about the actual conditions in Lake Champlain. Correct me if I'm wrong. I think there is a south to north flow of water in the lake along our shore. So that spit probably formed from the south to the north is what I'm guessing. That could have been a mixture, because the water flows both ways. But ultimately, it goes into the river that goes north. It's not necessarily, you know, if the river is discharging, the lake is discharging. It's not necessarily the way it's suspended, but it's more the dominant wind direction that creates the waves. The waves put the sand up. It goes up at an angle with the wind direction, and then a wash flows back down due to gravity, straight down. So it gradually moves forward with the wind. What about at the north end of North Beach? There's a lagoon there, I think. I mean, there's a wetland area, there's some open water, but that's just south of the rock point. So that was a place where, you know, the wind kind of gets stopped by the rock point. Should have invited one of my colleagues from the DC works on Lake Champlain to answer those questions. If people did have follow-up questions, how could they ask them? My, so I'm doing this as a geologist, I don't necessarily have my state hat on, but I did put my email. We can write some things. Okay, yeah, so appropriate to send your email. I think we'll send out everybody who registered that information. Just keep in mind that we're incredibly busy. Could I be, I don't believe I'm just trying to get through the question. I'm going to send out. Hi there, are there any other online comments or questions? I just got one more question about the barge canal area. Is that open to the public to visit? Well, that's, that's a somewhat of a complex question, Andy, and I'm glad you asked it because the barge canal is private and public plain, and it's not formally open to the public to visit, but there are no sensors that keep people out. So people have been visiting the barge canal for decades. And so it is sort of a quasi public accessible area. It's not officially public, but for people that wanted to come down and visit with people who have spent a lot of time there, friends of the barge canal is offering many tours on the first Saturday of every month starting on June 3rd at nine o'clock in the morning. So anybody who wants to come down at nine o'clock on June 3rd and then subsequently every Saturday throughout the summer into the fall, that would be a great way to come down and visit. And if somebody couldn't come on a Saturday morning, they could certainly contact friends of the barge canal and we could arrange a small group to walk down there because I know that if you don't know the area, it can seem a little bit confusing or intimidating, but to walk, once you walk down through with somebody who has regularly walked there, it's much easier to conceive of and you have the map, so you have kind of a conceptual idea, but it's good to have a guide. So people want more information about friends of the barge canal or about the barge canal and access to it. Our website is pinestreetbargecanal.org and Carolyn is holding up the map with our information on it and our email is sosberlington.com. Very roughly, how much private and public areas? There are 28 acres total with the water. There are 11 of those acres are owned by the city. The rest of it is private land, but there's a transition happening where that private land, except for the four acres that Gramminton was running to in 453 Pines Creek, where they were planning to build a bathhouse, is going to be donated to the city, so it will be conserved. It will be conserved land. And how much is that? I think it's 24 hours. 24 acres. But how much is she donating? She's donating approximately four acres. And then along with that, the acres that she's buying, she's buying the, I'm speaking of Joe Neal King, right, so bathhouse, she's buying from Red Davis all the land that's on the other side of the canal, except one, I'm pointing in the wrong direction, but one piece, one parcel that is owned by Scully, and Hula, and he bought that when he bought the property, so that also is going to be donated to the city. So Russ is donating his, yeah, okay, and she is, but how much land does she donate? Well, about, about, about five, 10, no, more like 12. Oh, okay. So it's really equal to what we have now. Yeah. There's a city, and then that's going to hopefully be all conserved. Yeah, that's the plan, and that's part of the work of the friends. And then there'll be some sort of perk or not just always conserved. Well, that's under discussion. Okay. Possible? Yes, it'll probably be under the, under the aegis of Parks and Rec. I'm saying we'll be able to access them. Well, that's a discussion that we have. Still have, okay. So there is public access, we have permission from the private land owners to cross that, that land, to get to the public land, and we've done a considerable amount of cleaning on that land. So there's nobody saying, no, don't go there. Just a hint, we have a gate. Don't read or something. You can walk around it. Oh, you just can't drive around it. Oh, okay. Okay. So thank you everyone for coming. Thank you for having me.