Nick Hastings: There you go perfect great.
Nick Hastings: Alright, if you unsure, then I will.
Nick Hastings: One minute late already here, here we go but that's okay.
Nick Hastings: So welcome everyone, this is a session T eight.
Nick Hastings: Also, the lucky short straw drawer of being first in the morning on this first day of the Conference, so welcome we're here to have some presentations on environmental hazard geology and innovations in geologic environmental investigation methods so hopefully you're in the right place.
Nick Hastings: My name is Nick Hastings and with water and current senior hydrogeologist.
Nick Hastings: 30 something years in the business and 21 it would hurt concurrent I do a lot of Environmental Investigation remediation work specializing on ground water surface water interaction and run our sediment technical team for the company.
Nick Hastings: And with me is Mike.
Mike Apfelbaum: Thanks Nick my name is Mike off bomb co moderating with Nick this morning I also work with ticket, what are the current i'm a senior geologists and project manager and specialized in sight characters site characterization methods, a practice leader in that area, as well as implementing.
Mike Apfelbaum: groundwater and surface water remedies.
Mike Apfelbaum: morning everyone.
Nick Hastings: morning everyone Indeed so, just a few housekeeping items.
Nick Hastings: we're going to introduce Mike and I will alternate introducing each speaker just before the the the toxins, there are quite a few of them and listing them all off and introducing them up front would be.
Nick Hastings: little time consuming but also if you have short term memory loss, like some of us, then you won't remember who were we're seeing next.
Nick Hastings: Please keep yourself muted until the Q amp a section we're also encouraging putting your questions in the chat.
Nick Hastings: During the talks and we will have questions at the end of each talk we're going to try to leave a couple minutes for that.
Nick Hastings: If there are no questions in the chat or if we've gone through them, and there is extra time then use the raise hand feature to raise your hand and I will call on you, and you can unmute and ask your questions.
Nick Hastings: With that our first speaker so that we can be Crispin on time is mark Higgins from yukon's department of geosciences and he'll be presenting on deriving spatial Hydra geologic data sets from digitized legacy well records so take it away mark.
Mark Higgins: Thank you, Nick.
Mark Higgins: So thank you everyone for being here i'll start by just acknowledging my co authors and department of public health, because they.
Mark Higgins: Funded this effort, last summer, through the Department of natural resources, that with an agreement, they have to have summer interns and to get students involved in the pH work, so this is a demonstration that we did for them.
Mark Higgins: About relating to legacy well records and how they can be used if proper data management protocols are put in place to digitize old records and.
Mark Higgins: make them available to be used as spatial data sets and so to give some background and give an overview.
Mark Higgins: Connecticut well completion reports as anyone who's a environmental professional knows in this state at least that these are available online going back through the 70s.
Mark Higgins: And there's over 322,000 or more wells that have been drilled in Connecticut for every single well well completion report is filled out with some some.
Mark Higgins: information that is this could be very useful to many of us, which will go through later, but it is a it's a great resource when you think about it.
Mark Higgins: But there's some challenges associated with it, some of them being data management related like they're not organized systematically the way that they're online.
Mark Higgins: they're organized by township and by year, that they were drilled So if you want to find some wells, in a certain area that you're interested in looking at the data for you need to know for guests at about when those wells were drilled.
Mark Higgins: And then you have a file dumped that's really an image dump of every record that was drilled that year.
Mark Higgins: And then picture, so you can't search through any of them and then they're not alpha ties in any way, so you kind of just got to scan one by one.
Mark Higgins: Through each one until you hopefully find an address or something that will tell you that it's the well you're interested in other challenges are they're not always legible.
Mark Higgins: they're not always read of all because many of them were scanned in years after they were mailed into department of consumer protection, or whoever was managing the data at that time.
Mark Higgins: The data quality is also.
Mark Higgins: When relying on these data to answer questions or these reports, you definitely should keep in context that the quality is not always consistent or perfect.
Mark Higgins: there's sometimes missing information.
Mark Higgins: there's inconsistent descriptions, you know things vary from journal driller to driller you know what was going on that day, if you look at the how the geology was logged in one well on the left to compared to the one on the right, you have overburden in bedrock.
Mark Higgins: And then here you actually have some more detailed descriptions of each unit and oftentimes what i've seen after going through thousands of these is that.
Mark Higgins: it's they'll name off rock types that aren't even in this state so so you got to take it with a grain of salt there's long term shifts and groundwater table so.
Mark Higgins: That that couldn't that can be a challenge or data quality issue and then there's missing address info sometimes because sometimes wells were drilled before modern street Games were even there so.
Mark Higgins: If there's all these issues, then why am I telling everyone that we should we should take advantage of this and use it well, there are very, very significant benefits if you.
Mark Higgins: Take into context those challenges and filter out or account for them and the way you use the data there's temporal depth there's never ever.
Mark Higgins: replacement with any legacy data there's never a replacement for time in history, so so you can answer questions, especially in this case about.
Mark Higgins: You know how water tables in the area may have changed over decades there's greater spatial coverage than you could ever reasonably get nowadays, if you were to drill wells, for the purpose of gathering information around a town wide scale region scale.
Mark Higgins: And then there's when it's implemented property, it can properly, you can really get some some insights prior to.
Mark Higgins: Making a plan to go spend on new data collection efforts and that's really what we're focusing on here is what was what what those insights can be so now i'm going to go through what what we did last summer.
Mark Higgins: Where we focused on one township and digitizing all of the old bell records from the down township as a demonstration of what you really what.
Mark Higgins: Questions you can answer if the State were to launch efforts to digitize all of the records throughout the state and how this would be a useful tool for.
Mark Higgins: scientists, researchers and you know the hundreds or thousands of environmental professionals they're doing contaminated investigations around the state.
Mark Higgins: So, in a particular town i'm not I don't think i'm supposed to mention the name quite yet.
Mark Higgins: So i'm not going to but we digitized 1700 well records going back to 1971 and we put them into a Microsoft Access Database and so these are what the majority of the law completion reports look like they still look like this now.
Mark Higgins: And they haven't changed in 50 years and so some years ago meredith metcalf at Eastern made a digital a digital form.
Mark Higgins: That was launched and implemented into a Microsoft Access Database and it matches what the drillers are used to filling out in the field and sending into the state anyway, but when you if you enter each of these fields in from the form on the digital form.
Mark Higgins: it's linked to a to a number of spreadsheets or access databases and they can then be queried and they're all in one place in a systematic way, so you can extract the relevant information.
Mark Higgins: Because if you can there's all of these fields, but not all of them may be relevant to you if you're thinking about it in terms of spatial data sets but.
Mark Higgins: I went over some of the quality issues, but at least at the very least the minimum what's reliable and there for every well completion report is an address the depth to rock.
Mark Higgins: the depth of the driller encounter water, the well yield because they do a yield test for every well that's used for water supply and then you have to completion depth.
Mark Higgins: So if you query those specific fields, among others, that may be useful to you, you can import it into our GIs and create a jira database.
Mark Higgins: And so, in GIs you can GEO code all the addresses automatically, and you can get approximate well coordinates by doing that and, for me, you have different choices, I chose the Center of the parcel.
Mark Higgins: For the for the dresses and that's the approximation of where the well is the well coordinates can then be used so each of these points is where I practice as well.
Mark Higgins: And this is the lidar surface elevation layer it's available to everyone, through CT ECO or CT deep and you can now get this ground surface elevation for every single well, so now for every well, we have the coordinates are where it is surface elevation and then these other.
Mark Higgins: Data points are fields that we already had, and so, if you cross reference the surface elevation and every well to the depth of water, and you can interpolate between.
Mark Higgins: Every single wellpoint and you can generate a potential metrics surface map or a groundwater elevation map of the entire.
Mark Higgins: area that you're studying in this case, this is 1700 points in a town that's you know a few square miles so that's pretty decent spatial coverage for for a map like this.
Mark Higgins: If you have we have depth to rock for every single well, you can interpolate the the bedrock typography if you.
Mark Higgins: use that between all the wells, and you can generate a topographical map of the bedrock and, if you remember what the surface topography look like.
Mark Higgins: It matches pretty well so so the data quality indicates that that this is pretty decent representation on this scale.
Mark Higgins: The surface elevation minus the bedrock elevation gives you the overburden thickness which can help answer a number of questions whether it's recharge or migration pathways for a contaminant release or something like that.
Mark Higgins: You can delineate groundwater flow boundaries based on this potential metric surface map so now i'm getting to some more secondary or advanced analysis.
Mark Higgins: So, if you think about how you delineate watersheds from the surface typography you can also do that to the top of the potential metric surface of the groundwater topography and.
Mark Higgins: If you consider that those don't always match up this is an example from that meredith used in one of the papers from a while back where the ground water drainage basin, so the groundwater, you could think of is groundwater.
Mark Higgins: watersheds versus surface watersheds and you can even look at the bedrock topography basins as well, they don't always match it up, so if you're thinking about it in terms of you know locating recharge areas to wells recharge direction or.
Mark Higgins: Thinking about groundwater sustainability or surface water protection source water protection, these can help you answer questions that you wouldn't otherwise be able to answer quite as accurately if you were just going by surface water shed analysis when it comes to recharge issues.
Mark Higgins: You can also then use this to visualize the flow directions, the groundwater flow directions in different areas of your of your study area or within each basin.
Mark Higgins: You can you can use these arrows on any scale these these flow vectors you can zoom in and see it a more refined version of that.
Mark Higgins: And from that.
Mark Higgins: there's not a great spatial representation of this but.
Mark Higgins: This is more of a spreadsheet arithmetic exercise that you can do.
Mark Higgins: For every single one of these groundwater basins of groundwater flow boundary areas that you've generated.
Mark Higgins: You can you can you have the area of that you can calculate the hydraulic gradient three those basins, by using the slope tool of GIs.
Mark Higgins: You can calculate the average specific capacity for every single one of those basins by averaging that over the wells in each base and because.
Mark Higgins: You have a yield report for every single well because the drilling Jeff did have to report that they do a drawdown test and a recovery test.
Mark Higgins: And you know there's there's there's a resolution, you have to understand the resolution to that, but it's there, so you can.
Mark Higgins: get an estimate and then from that can calculate the trends in the 70 the average transmissibility of an area or of each basin.
Mark Higgins: And then from all of those pieces of information, you can calculate the average discharge or flow rates or recharge rates through each basin, which is huge if you're thinking about.
Mark Higgins: Groundwater sustainability in an area that's seeing a lot of potential development for a lot of new wells being trails.
Mark Higgins: And so, ultimately, you know, this is, this is actually a pretty basic and quick.
Mark Higgins: Three 3D model that I generated just using our GIs this isn't even using model flower and a number of other tools, you can use for for groundwater modeling, but you can.
Mark Higgins: Then open this and art scene, which is an art GIs tool and put these layers in there, and you can visualize three dimensionally.
Mark Higgins: Where the different layers lineup where each of the wells are and how they might extend through each of the layers and so on, and if you were to map something, such as a contaminant earlies or or.
Mark Higgins: You know, some change to to surface water, or whatever you get you can use this to help you visualize what might be affected in three dimensions.
Mark Higgins: So this This really is to show you that, with a file essentially what was a file realm of paper data or dark data that was all collected by hand at some point and.
Mark Higgins: At best, a digital versions of it now, or that they're scanned into an image file done we've turned that into these three visualizations and you can do this relatively quickly, once the data is put in that in that in that format.
Mark Higgins: And so worthless data trust me i've come across a number of people that.
Mark Higgins: work for a number of agencies or firm is where.
Mark Higgins: there's five rooms, a day like this and people don't know what to do with it because it may not have been used or accessed in years or decades so both are thinking Oh well, we'll just get rid of it so it's going to use it it's worthless but.
Mark Higgins: Obviously that's not the case, because if it's managed properly, you can use it to estimate ground water flow rates and direction transmit cities.
Mark Higgins: That are rocking groundwater topography can help use it to help you identify potential receptors.
Mark Higgins: to contaminate releases, you can estimate migration pathways from overburden to the bedrock based on the thickness of the overburden near wells and and the topography of each of those layers.
Mark Higgins: And then you can just get a more accurate representation of recharge areas to wells, if you want to compare the different boundaries between surface.
Nick Hastings: ground water flow boundaries and backdrop basins.
Mark Higgins: And so, is it.
Mark Higgins: Is it, to put it into perspective.
Mark Higgins: The question is it worth it to digitize legacy data these massive data sets you, and if the data quality is lesser than your modern approach it costs.
Mark Higgins: From from this perspective, I think it cost about $10,000 of department of public health funding through yukon for two of us students to to.
Mark Higgins: Do this project over the summer I would think in the private industry with me take a bit longer or if this was implemented not through summer.
Mark Higgins: Research co OPS, but an entire town could be digitized and for relatively low cost, when you consider that the cost of one that rock well is $9,000.
Mark Higgins: So so to achieve the cost of 1% of the spatial coverage just using new data that's $150,000 allows right there, so if you sick some students on this over this couple summers and digitize the whole state the data that you get from that is incredibly valuable.
Mark Higgins: So to summarize and wrap it up new processing and visualization methods are essential to realizing the value from these old data sets.
Mark Higgins: And if you do that properly integrate these with data gathered using new techniques, if you understand the context and limitations, if you take the time to digitize historical data.
Mark Higgins: You can you can take advantage of this value, you have to understand that it was extremely expensive to collect this data at some point, you might as well take advantage of it now okay.
Mark Higgins: And another important point that people don't think about that this is an example of is that data management should be at least as high a priority is data collection, because we're still collecting data like this now and it's still.
Mark Higgins: Up until recently has not been implemented or prioritized in this way.
Mark Higgins: And so, one major update that's The reason is that the Department of consumer protection and Connecticut as a state has recently implemented a means for drillers to.
Mark Higgins: enter their well completion reports in a database similar to this that should be accessible to everyone at some point so that's an incredible success in progress, but.
Mark Higgins: Now we need to convince the state to also invest in the digitization of these old well records that go back decades, because it'll take many decades of.
Mark Higgins: Only new wells being entered into that database to have this as a useful tool, because again there's only knew was being entered into that and.
Mark Higgins: there's obviously decade's worth of data that would be more useful than waiting for the just the new wells to be usable so i'd like to thank you for for watching this.
Mark Higgins: If you have any questions about doing this type of work i'd be happy to talk to you about it.
Mark Higgins: i'm looking forward to being able to use this resource through the state in the years to come, so thank you very much.
Nick Hastings: Thanks mark.
Nick Hastings: And I was, I was taking a short course with a different version of this not too long ago.
Mark Higgins: Oh excellent.
Nick Hastings: Thanks EP EP oC.
Mark Higgins: appreciate the support.
Nick Hastings: We do need the continuing education for our licenses remember that.
Nick Hastings: So I do see a couple questions I don't know if you see them or, if you want me to read them to you and be happy to.
Nick Hastings: Christine asks, I wonder how well Massachusetts does with these well these data there's at least a searchable database that can point to the scan well completions.
Nick Hastings: Mass geological survey has done a lot of hands on driller training to improve the quality of current future well logs know much about the Massachusetts end of things.
Mark Higgins: I do not know much about mass I know that New Jersey, has had this for quite a while they've kind of been a.
Mark Higgins: really good example of someone that implemented this early on, so so a lot of people cite them and there's a.
Mark Higgins: high number of states, now that have jumped on to this, so I know I talked about this n G, who as well, and there was a lot of state agencies that were really interested.
Mark Higgins: in helping guidance, because they want to get on board with this type of resource, I see another question there it's from from Robert certainly one of the most reliable, what are the most reliable parameters and surfaces, you were able to generate from historical logs.
Mark Higgins: The reliable parameters were depth to rock and location look some of the locations for older wells, but really difficult to.
Mark Higgins: locate because they were drilled before there was modern street name, so you have to go by large number and that took a little a few extra steps of going through old development maps and parcel maps, but it can be done.
Mark Higgins: That interview so asked did the interpolation method to use look like it w for the water surface is differentiate between our preferred types some huge gradient and.
Mark Higgins: They didn't I did not different differentiate between the different types if this was a quick representation or a quick interpolation and if you were to look at different if you were to look at different.
Mark Higgins: depths, you could you if you wanted to take more time to filter out the data, you could definitely do that because that's that's contained in it looks like Stephen.
Nick Hastings: Stephen has his hand up as well, so if you want to unmute good.
Stephen Mabee: hi hi mark great talk, I appreciate, I feel, your pain.
Stephen Mabee: we're grappling with this in Massachusetts right now, but I have one suggestion.
Stephen Mabee: We went after a usgs water grant.
Stephen Mabee: water use data and research grant they every state is allocated $250,000 I don't know whether Connecticut has used all of those funds up yet or not.
Stephen Mabee: But we had not in Massachusetts and we went after and got 120 $5,000 and what we're doing is going back through the historical well completion reports in Massachusetts.
Stephen Mabee: and updating the historical information and getting it matched to parcels and Vermont is doing the same thing with Julio boyles in Vermont geologic service doing the same thing with these water grants, so if you haven't tried that avenue, I recommend it.
Mark Higgins: Absolutely, thank you i'm going to contact you after this to talk to you about that, thank you very much looks like we're out of time.
Nick Hastings: Good connection and thanks again mark and thanks for the questions everyone so Michael handed over you for the next.
Mike Apfelbaum: Alright, thanks, Nick.
Mike Apfelbaum: Before our next.
Mike Apfelbaum: presentation this morning we have Eon Russo presenting on the contribution of fresh submarine ground water discharge to the Gulf of Alaska already took it over.
Aeon Russo: Alright, thanks Mike.
Aeon Russo: Alright, so today i'll be presenting on the first ever estimate of submarine or coastal groundwater discharge the Gulf of Alaska, I would like to thank the Alaska nsf EPA score for support and the geological society of America.
Aeon Russo: Both for supporting this investigation and also like to acknowledge umass geosciences and the US Department of.
Aeon Russo: geological sciences at the University of Alaska anchorage together members of which together form the catch a MIC based dream team.
Aeon Russo: let's get to it, coastal margins are vast and important globally, especially in high latitudes tectonic settings like the Gulf of Alaska well freshwater and glacier mass balances have been heavily layered evaluated the coastal groundwater component often overlooked.
Aeon Russo: So there's essentially four flavors of coastal groundwater discharge first one is density driven recirculation The second is title and wave and just pumping.
Aeon Russo: The third is fresh meteorite groundwater.
Aeon Russo: The fourth is near shore grab water discharge.
Aeon Russo: This project focuses on the two freshwater components.
Aeon Russo: Together, which combined to make the total coastal fresh water discharge for region.
Aeon Russo: what's the big deal, although much smaller contributing volumetric Lee nutrient and Salim flux are comparable to river influxes of the global scale.
Aeon Russo: This is the groundwater being subject to a wider variety of decomposition and reduction pathways and surface water and some studies at GD nutrient flux actually greatly exceed local river influxes or proximal rogue river influxes.
Aeon Russo: that's even with the current global estimate putting a CG D at typically less than 1% this figure displays the ratio CD river flux at the global scale highlighting potential CG D hotspots.
Aeon Russo: When I first saw this figure I found it odd that high latitude regions in the northern hemisphere contributed minimally to this flux.
Aeon Russo: So that brings us to our study region of focus the Gulf of Alaska.
Aeon Russo: So the act of margin of the Gulf of Alaska is covered with low altitude mountain glaciers given here in light blue.
Aeon Russo: And only 1.7% of the total land area of North America, it contributes more than 12% of the total continental discharged establishing itself is having one of the highest run off to area ratios in the world.
Aeon Russo: So why is a Grad student from Massachusetts concerned with the Gulf of Alaska.
Aeon Russo: Well, I was lucky enough to join a five year project that it just started at the beginning of my graduate program and left for catch make Bay Alaska during my first week at umass to join.
Aeon Russo: The kitchen MAC based dream team.
Aeon Russo: So during our field campaigns, we get to observe harvest deals and Wales and our boat transports to sites.
Aeon Russo: And then attempt to unload from the boat and hike into the back country with a lot of awkwardly shape science equipment here is pretty much the majority of the team right here, and one of our.
Aeon Russo: More out there sites.
Aeon Russo: We pack rafts measure discharge clicked isotope and geo cam water samples set up gauging stations and protect ourselves and our equipment from bears.
Aeon Russo: spending time in the field was crucial for the development of this project as We walked over the vast big glacial our walk planes I started to think about the unseen component of the freshwater beneath this.
Aeon Russo: In this triangular irregular network and catch McVeigh you'll notice ternary settlement settlement or Terry deposits extending out into the bay.
Aeon Russo: here's a big one in the was in ski and a big one over here in the grooming for that last picture was.
Aeon Russo: If you take away the contributing watershed areas of the streams that we measure you'll notice that there's still some of these stream list coastal catchments left behind.
Aeon Russo: let's take a closer look at a prime example.
Aeon Russo: This is the was designed to be river with it's contributing watershed areas shaded and superficial geology separated between could ternary sediments and bedrock.
Aeon Russo: you'll notice to have these streamline coastal catchments on either side of the top to graphically defined watership boundary.
Aeon Russo: let's examine what this would look like in cross section.
Aeon Russo: These Colocation Mr composed of thick highly conductive sediments underlined by bedrock there recharged from both melt and rainfall runoff infiltration.
Aeon Russo: and diffuse rainfall and snow melt recharge groundwater discharges, either as submarine groundwater discharge or springs near to the coastal margins are the water table begins to intersect the land surface.
Aeon Russo: This conceptual model is the foundation of this project.
Aeon Russo: So some specific research objectives is to estimate the contribution of coastal groundwater discharge the Gulf of Alaska isolate potential CG hotspots in the Gulf of Alaska and then evaluate changes in the coastal Cashman hydrological regime for multi-decadal timescales.
Aeon Russo: So let's get to the input data required for this project.
Aeon Russo: First is the usgs one one K DM necessary to delineate the water's edge of the Gulf of Alaska.
Aeon Russo: The geologic map of Alaska is used to isolate coastal catchments the drain eternity deposits versus bedrock.
Aeon Russo: And most importantly, we need to recharge inputs for the coastal fresh groundwater.
Aeon Russo: beamer at all use the suite of physically based models to estimate the total freshwater discharged the Gulf of Alaska.
Aeon Russo: They took meteorological for things, combined with the glacier mass balances to estimate grid by grid run off for the entire God, resulting in 14,052 outlet points, driven by a variety of.
Aeon Russo: Sophisticated models, this is the climate forecast system we analysis they use.
Aeon Russo: Micro that was used to interpolate the meteor logic, forcing snow model computes the full evolution of the snow water equivalent of snow and the geo a.
Aeon Russo: Soil balance computes et surface and baseball run off they had a glacier mass balance in there and hydro flow is used to route, the runoff through the system grid by grant.
Aeon Russo: So let's take another look at this conceptual model.
Aeon Russo: So, in order to use the beemer at all model results for recharge inputs, we must assume that all model discharge actually spends most of its time as groundwater.
Aeon Russo: Which is a reasonable assumption, given that the glacial fulvio out wash typically has very high Hydra other activities ranging between one and 50 meters per day that's over an order of magnitude higher than the maximum of precipitation are melting rate in the region.
Aeon Russo: which makes it a reasonable assumption, we also assume that runoff from bedrock or glacier surfaces ends up entirely is.
Aeon Russo: run off infiltration when it hits the coarser moraines talus cones and all of your fans at the bedrock margins.
Aeon Russo: Now we can finally take a look at what we did.
Aeon Russo: The one kilometer resolution DM was used to delineate about 1076 water says the drain districts, using a flow accumulation threshold of 20 square kilometers coastal catchments are essentially the leftovers after this computationally and mentally expensive process is complete.
Aeon Russo: let's take another look at catching back Bay again.
Aeon Russo: Here you see the leftover coastal catchments in green between a network of streams and contributing watershed areas.
Aeon Russo: This is what bicoastal catchments look like at the regional scale.
Aeon Russo: Remember, in order to use the high resolution model discharges our recharge and puts coastal catchments must further be extracted by locations within the highly conductive contrary sentiments of the gla.
Aeon Russo: By doing so we eliminate the coastal catchments terminate into bedrock which have a much lower infiltration capacity.
Aeon Russo: This is a schematic on the process, so we have purple ternary sediments overlain by these original crystal catchments you notice that when coastal catchments are extracted by geology their size is greatly diminished.
Aeon Russo: So here's another example from catching back bay and the southern Prince William sound to observe this reduction in coastal catchment size.
Aeon Russo: you'll notice return the sediments given here in yellow and then coastal catchments of bedrock or grey and how that size, has been reduced, this method.
Aeon Russo: Here we provide some summary statistics from this watershed extraction method in total crystal catchments are less than 10% of the total contributing watershed areas to God and coastal catchments the drain draining ternary sediments only around 2.7% of the total contributing area.
Aeon Russo: The cemetery environments only represent about 33% of this predominantly rocky mountain is coastline.
Aeon Russo: Now we have everything we need to estimate CD from these coastal catchments and evaluate any changes in the runoff over the past four decades, and this figure high values of model discharge represented by the large blue circles.
Aeon Russo: And they correspond to the stream networks as you see.
Aeon Russo: The darker circles are low values of Q from the model discharge runs.
Aeon Russo: And they land within these coastal catchments only some of them land within our outlet from these quick ternary deposits, as you can see here and a lot of them are just going to be modeled as a runoff from these bedrock coastal attachments.
Aeon Russo: So these coastal catchments are grouped and further extracted based on containing model discharge outlets.
Aeon Russo: weights are extracted or discharge outlets are some free coastal catchment points are extracted and snapped as poor points to read delineate contributing area.
Aeon Russo: And then mirrored mean clearly fluxes are calculated from daily time steps over the 40 year model run and yearly discharge rates are also calculated and served observe any multi-decadal changes and a regional cegb.
Aeon Russo: And drumroll please here is a map of group fresh coastal groundwater discharged from the literary sediments of the Gulf of Alaska classified by ranges and kilometers cube by year.
Aeon Russo: From this map, it is easy to observe where see CG hotspots occur.
Aeon Russo: let's take a closer look at some of these hotspots.
Aeon Russo: First let's go to cook inlet Here we see both area and geology is dominant driving mechanisms for this estimate.
Aeon Russo: go over to the central coast where ribs are the highest discharge rates.
Aeon Russo: Glaciers proximal to the coast dominate this region, which not only leads to high surface discharge but likely leads to enhance coastal groundwater discharge as well.
Aeon Russo: Coastal groundwater discharged average, around a 3.9% of the total freshwater flux, the gla over this 40 year time period we're calling this is only from 2.7% of the land surface in an area that has the highest area to run off or run off the area ratio, one of them in the world.
Aeon Russo: Pretty big fighting let's look at some yearly totals now.
Aeon Russo: You can see high yearly variability from the total freshwater discharge, this is total freshwater just started giving them blue here.
Aeon Russo: But you'll also notice a steady increase as we approach, people are in the region.
Aeon Russo: lows typically coincide with strong linear years well peaks typically coincide with strong El Nino years.
Aeon Russo: Now let's look at this same graph for the coastal groundwater just charged catchments.
Aeon Russo: Given here in green.
Aeon Russo: you'll still see yearly variation the slightly less dramatic.
Aeon Russo: And looks like it's also increasing over time.
Aeon Russo: let's stack and compare these two.
Aeon Russo: So over the 40 year time period total freshwater discharges increasing by an average of about 0.15% per year.
Aeon Russo: While total CBD is increasing by about 0.6% per year so relative contributions of coastal groundwater discharge are increasing at a rate that is four times higher than that of the entire drainage basin.
Aeon Russo: So.
Aeon Russo: Would we find Well, this is the first ever study to estimate CG the Gulf of Alaska even locally.
Aeon Russo: This study highlights substantial gaps in saw you in fresh water transport to the Gulf of Alaska it has brought implications for current fresh.
Aeon Russo: Current coastal Salyut and nutrient flux is and then it can be used in future modeling studies, such as salt water intrusion ocean circulation.
Aeon Russo: And then title pumping and density driven recirculation which with extreme tides like five to 10 meters in the Gulf of Alaska could be the main driver of CBD or STD.
Aeon Russo: may also be linked biological phenomenon salmon runs toxic algal blooms and diatomite photo plankton abundance just to name a few.
Aeon Russo: So some things we're working on right now.
Aeon Russo: we're going to further separate this down into sub regions and the gla.
Aeon Russo: explore the timing from daily daily time series of averaged over the 40 year time period and then perform some sensitivity analysis.
Aeon Russo: Using small flow or accumulation find a resolution DM course resolution recharge and puts like the global and no simulation system from NASA and then total flux from coast coastal candidates not differentiated and then explore land cover typography catchment size effects on CD.
Aeon Russo: So that leads us to the comments and questions time.
Aeon Russo: While we do that enjoy some photos from a deep exploration of the Gulf of Alaska while I spent last summer there, this is in the copper river drainage, this is devil's Canyon of the sioux city.
Aeon Russo: says underneath a ice or a glacier and ice game look in a positional environment willow creek and, of course, the northern lights thanks.
Mike Apfelbaum: Alright, thank you, young a great presentation so with that any questions for you, on.
Mike Apfelbaum: This point.
Nick Hastings: I think we're all having a field work location envy right now.
Nick Hastings: Somehow bridgeport Connecticut doesn't stack up no.
Aeon Russo: yeah pretty blessed to be out there.
Nick Hastings: Like you got a hand raised yep.
Christine.
Christine Hatch: yeah hi yeah fantastic presentation that's phenomenal work i'm curious, since you spent all this time out there, how did anybody measured directly the submarine gross motor discharge it so how close.
Aeon Russo: Was.
Aeon Russo: That was my plan just looking like yeah that's my plan this past summer my road you know, had had some funding for it and everything and they told him I wasn't able to get out there till August.
Aeon Russo: And so my whole master's thesis kind of got thrown on its head and that's where this project came from.
Christine Hatch: Well way to make lemonade out of lemons man, it looks awesome well done thanks.
Mike Apfelbaum: The others out there.
Mike Apfelbaum: Are you are you finishing up this year is this your last year, for your.
Aeon Russo: yeah i'm the research final push here.
Mike Apfelbaum: was our.
Aeon Russo: everything's we're trying to get it out to publication ended the month so.
pretty much done.
Nick Hastings: So no more field work this year.
Aeon Russo: I think i'm going to go back for another field season.
Aeon Russo: To help us some some future work and then also try to quantify it locally in our catchments.
Aeon Russo: The problem is like the whole well data that was talked about the first talk there's two public so open source wells, and the entire gulf of Alaska so it's really hard to.
Aeon Russo: Even check out these grandmas fluctuate and like we're assuming zero.
Aeon Russo: You know recharge from other surface waters, you know all these coastal catchments are kind of placed right at the outlets of these huge rivers.
Aeon Russo: That likely lose a lot of water, you know some some studies have shown that 50% of the water is lost to these kind of adjacent aquifers so it's probably it's likely a gross underestimation of the actual discharge.
Nick Hastings: we're working with some big Lego blocks and broad assumption so long.
Nick Hastings: Exactly scale is a.
Aeon Russo: regional scale that's.
Nick Hastings: You know that's very well explained thanks.
Mike Apfelbaum: Great any other questions.
Mike Apfelbaum: got one from from Janet.
Mike Apfelbaum: i'm gonna go ahead and read that Ian.
Aeon Russo: i'm just seeing them now check it out.
Mike Apfelbaum: I can read it to me yep I can get going to do you have a sense of what's driving the increase discharged.
Aeon Russo: So yeah right now we're seeing a shift.
Aeon Russo: Not only increase in overall precipitation which these are the main drivers and the small coastal catchments they're low altitude don't have a lot of ut just because they're usually void of all plants and vegetation.
Aeon Russo: And there's an overall kind of transition right now going on from dominated by snow melt to dominated by rainfall and also increasing intensity of storms.
Aeon Russo: So it seems like, especially in the last decade that's what's been driving it we're still working with more of an Alaska climate gas we're still going into that kind of detail right now.
Nick Hastings: alright.
Nick Hastings: last question so otherwise we'll with thank yous to Ian will move on to the next talk.
Nick Hastings: Alright, so next up is Eric Moore from uconn natural resources and the environment department and he will be presenting on linking land use legacies connecting groundwater nutrient export to historical land use, using my path.
Nick Hastings: Go ahead Eric.
Eric Moore: awesome thanks for the introduction.
Eric Moore: Good set.
Eric Moore: up here, you can see my screen.
Eric Moore: Okay yeah thanks to everyone who made it out this.
Eric Moore: Early on a Sunday morning.
Eric Moore: i'm excited to share with you part of my dissertation work.
Eric Moore: Looking at linking land use legacies and using mountain path to track nutrient export partnerships.
Eric Moore: like to acknowledge my my funding sources, the nsf and the usda and all the field help that we've had over these past four years.
Eric Moore: Groundwater may receive excess nutrients from historical land use practices, because the nutrients that aren't transported during surface runoff are then incorporated into soils.
Eric Moore: And some of these nutrients will be processed within the soil Eres la the remainder will infiltrate into groundwater.
Eric Moore: nutrient processing can also occur along groundwater flow past due to long residence time in groundwater.
Eric Moore: and groundwater residents time or orders of magnitude longer than surface waters, creating legacy affection, historically, and these practices.
Eric Moore: We posture that groundwater discharges or an important non point source of legacy nutrient loading throughout river networks.
Eric Moore: And in the agricultural Midwest surface water and groundwater nutrient concentrations are highly correlated with land cover but in New England, we have a more complicated landing system.
Eric Moore: In the 1800s we see a lot of clearing of the original forest for agricultural land use and these boxes and arrows represents some sort of groundwater lag time associated with the overlying land cover.
Eric Moore: Throughout the 1900s with the boom and population, we see a lot of development in New England land cover and it's going to take some time for the nutrients from that development to infiltrate to ground water sources and an export towards the stream.
Eric Moore: And at present let's say we implement a best management practice and.
Eric Moore: restore this agricultural field with some forests, it still may take some time for the forest to clean up those excess nutrients and then discharge and groundwater.
Eric Moore: And while these conceptual diagrams make it and simplify our understanding of groundwater flow we don't understand the nuances of where groundwater inner surface waters and the legacy nutrients associated with these groundwater discharges throughout entire evernote.
Eric Moore: So in our research group we use thermal infrared cameras to locate firmly anomalous preferential groundwater discharges.
Eric Moore: As figure on the left is showing some drone imagery of a wetland taken in winter, so the blue cool temperatures that you see in the stream and wetland here are surface water and this red plume is groundwater floating On top of that surface water that we identified using drones.
Eric Moore: You can also use handheld thermal red cameras to identify groundwater discharges and then panel a here, you see a graduate student measuring the.
Eric Moore: extent of a granddaughter safe on the order of 10 to 15 meters along this river bank side here and the blue colors in the summer images represent colder groundwater entering surface waters.
Eric Moore: Groundwater discharges can also be very small of the sub meter scale so here are my toes and our little temperature probe measuring there, and while they can come through sandy sediments we also see brown water just charges in rather rocky settlements as well.
Eric Moore: In there, so the research objectives for this talk or to map the space for distribution of these groundwater discharges throughout the farmington river watershed and then characterize nitrogen dynamics at groundwater discharges and their relationships to sounding surrounding land use.
Eric Moore: So here's our study site, the farmington river watershed so fifth order tributary to the Connecticut river located in central matching T shirts, with its headwaters in Southwestern.
Eric Moore: It covers around 1500 square kilometers.
Eric Moore: And is mainly consistent of forest land cover the River starts up in this forested catchment appear flows south east word.
Eric Moore: And then comes into contact with the suburban area of Bristol and flows and around 25 kilometers northward around the suburban area part for before discharging to the Connecticut river.
Eric Moore: And over the last four summers using handheld methods we've surveyed over 50 kilometers of river reach throughout this watershed and math well over 300 bankside groundwater discharges.
Eric Moore: And so after we locate these groundwater discharges, we then go back and sample a subset of them for a suite of biogeochemical variables, we were to insert a small push point.
Eric Moore: Henry sampler well into the groundwater discharge and then use a syringe to pull out groundwater before accident to surface waters, and while we took a suite of variables in this talk i'm really going to focus in on the nitrogen species.
Eric Moore: So, putting our chemical data onto the our study site map, you can see that we surveyed 18 separate river reaches for groundwater chemistry, culminating and 172 groundwater samples, and these points are colored by their total dissolved nitrogen values shown in this scale here.
Eric Moore: And for every REACH and every day we're out, we also took a surface water sample to compare with our groundwater discharge chemistry samples.
Eric Moore: This is what our surface water data across the watershed looks like split up by stream order here and we can see rather low total dissolved nitrogen values across surface water.
Eric Moore: In our watershed aside from one high point in the River here where words which is likely wastewater drainage and summer.
Eric Moore: But our groundwater data tells a different story.
Eric Moore: We see a lot of heterogeneity in the fifth order river reach along the farmington maine portion of the liver here and overall groundwater total dissolved nitrogen concentrations were higher than surface water concentrations.
Eric Moore: And so to understand the heterogeneity along this fifth order river REACH, here we intensively surveyed this 25 kilometer reach so for every meter of this 25 kilometer REACH, we have active inactive groundwater discharge.
Eric Moore: So, putting that plot on a longitudinal axis these blue bars show where we located groundwater discharge along that that REACH and the lateral extent.
Eric Moore: Of the groundwater discharges that we found.
Eric Moore: The plotting our total nitrogen data longest access as well, we see a lot of heterogeneity with sometimes rather low below one total dissolved nitrogen right next to the high close to seven.
Eric Moore: parts per million nitrogen why we see this nitrogen export we also see evidence of Dean actual vacation in the second graph or access into gas at these groundwater discharges.
Eric Moore: We also see accumulation of ammonia due to nitrogen processing along this REACH and incomplete Dean extra fixation.
Eric Moore: along this reach as well, so what really drives the spatial heterogeneity is one of the main questions i've been looking into.
Eric Moore: Our first hypothesis.
Eric Moore: Was that localize forests and man cover may help clean up and reduce nitrogen concentrations close to the stream within a buffer.
Eric Moore: But it could also be like the diagram I showed earlier with the entire infiltrating area is contributing to that groundwater nutrient concentration.
Eric Moore: could also be that biogeochemical processing along groundwater flow paths are the main driver overland cover.
Eric Moore: And while it's relatively easy for us to compute a buffer and archie is and for us to compare our chemical data, the infiltrating length our was a bit more challenging.
Eric Moore: So we use the best MOD flow model from Janet Barclays 2020 paper as input into a MOD path particle tracking model to track water particles across this entire watershed so we overlaid the 300 by 300 meter grid.
Eric Moore: And then just dispersed a million particles across all of these models start cells shown here.
Eric Moore: into those 18,000 models start cells and then track those particles to their ending cells shown in blue here along the river REACH.
Eric Moore: And that culminated in around 2300 model insoles generally following the national hydrotherapy data set here.
Eric Moore: And so MOD path allowed us to track the particles, but also gave us groundwater residence times.
Eric Moore: median residence time was only 1.6 years, which is a lot shorter than we expected and our Max was around 16.6 years we were able to predict with this MOD path model that groundwater discharge would occur at a within a certain distance.
Eric Moore: At 150 of our hundred and 72 samples groundwater discharges indicating that we can predict where ground water discharge throughout this watershed rather well.
Eric Moore: And so, while i'm just showing.
Eric Moore: Land covered here, we can then look back at other historical land cover data and calculate Lang Lang cover per cents for every single model start so.
Eric Moore: And because we have this connection between where the product growth start and where they end, you can then lay those other land cover years over it, and then calculate the historical land cover change feeding these model in cells, where we predict groundwater discharge.
Eric Moore: So in this kind of crazy gif figure, here we have seven different land cover years going back from.
Eric Moore: And then, this highlighted purple box here, you can see, as land cover changed throughout this watershed you can see that link of a change in where we predict groundwater district.
Eric Moore: And so here's some of our results from our initial buffered Lancaster model.
Eric Moore: We why we do have a significant negative relationship with localized buffer land cover.
Eric Moore: You have a rather weak predictive relationship with our increasing forested land cover and our total dissolved nitrogen data.
Eric Moore: And this is this graph and the heterogeneity within this graph is really driven by the fifth order farmington river that I showed earlier with a wide range of total dissolved nitrogen values across various.
Eric Moore: Forests, it may uncover.
Eric Moore: Or the infiltrating area land cover model, it looks similar and we have a significant predicted relationship, but this relationship is weaker than force of Vancouver, which is the opposite of what we expected.
Eric Moore: And so we were.
Eric Moore: These models were super interesting for us because we see a lot of the heterogeneity driven here, but really at this in this graph this graph is driven by smaller order watersheds and we believe this is suggested that our our model may not be made up predict as well in headwater streams.
Eric Moore: And so we're right now we're looking into how biogeochemical processes throughout the watershed.
Eric Moore: I really drive these nutrient concentrations.
Eric Moore: And so here's.
Eric Moore: Four plots of our.
Eric Moore: Some of our other chemical data compared with total dissolved nitrogen.
Eric Moore: And we don't see much of a relationship with dissolved oxygen and total dissolved nitrogen, which is rather surprising, but we do see a relationship with conductivity and total dissolved nitrogen.
Eric Moore: And we suspect that this relationship is driven by human alterations such as road salting and urban development infiltrating the groundwater system.
Eric Moore: We do not have a significant relationship or denazification and total dissolved oxygen indicating that we can't predict where groundwater is going to be processed as it's entering surface waters throughout this river network.
Eric Moore: But we do have a significant relationship with are incomplete, the natural vacation indicating that denazification may not be completing itself and then therefore releasing the harmful greenhouse gas nitrogen oxide, to the atmosphere.
Eric Moore: And so, our conclusions our groundwater discharges are prevalent throughout the farmington river watershed and they're spatially chemically heterogeneous.
Eric Moore: And we believe that biogeochemical processing along ground order flow pass a mask with connection to hoard historical land cover and groundwater nutrient dynamics.
Eric Moore: And so, for our future analysis and for this upcoming summer.
Eric Moore: To get another landscape metric we're going to be looking into sewer versus septic area, now the sewer area for this water shows overlaid and it's Gray scale here.
Eric Moore: So for every developed land cover for every house not amongst this area is likely on a septic tank.
Eric Moore: And so, these leap wiki septic tanks, maybe driving some of these groundwater nitrogen concentrations as well.
Eric Moore: And for this upcoming summer we're going to go back to some of these groundwater discharge is in sample at a depth integrated scale to see how nitrogen is being processed at the end of these wonderful pass.
Eric Moore: Thank you.
Nick Hastings: Thanks Eric that's great and we do have a couple questions in the chat I don't know if you can see them or i'm happy to read them to you.
Eric Moore: yeah go ahead, read it.
Nick Hastings: So the first is from the illustrious Jerry robbins.
Nick Hastings: i'm going to call them that, how do they How did the groundwater discharges correspond to changes in soil hydraulic conductivity.
Nick Hastings: How did you measure K along the stream reaches.
Eric Moore: We actually didn't measure hydraulic conductivity directly.
Eric Moore: A lot of the hydraulic conductivity data really came from the MOD flow model from Janet Barclay and those are derived off the superficial material GIs layers.
Eric Moore: We do plan on going back to these ground water seeps and using some metrics and some instruments to measure this directly in the coming summers.
Eric Moore: I will say that we expect groundwater to discharge along the river bank sides not really under the River because of a high K cap of hydraulic conductivity along the river bed, so we expect the groundwater to come in along the sides here.
Eric Moore: Good question.
Nick Hastings: And then, Christine has asked as part of the long island sound our CPP project we were hoping to use nitrate data.
Nick Hastings: From Connecticut deep by small watersheds to target outreach and nutrient management practices for farmlands based on your knowledge of the watershed how effective, do you think this targeting hotspots approach would be.
Eric Moore: um I would say so, our model is really only at the 300 meter by 300 meter scale, so if we wanted to look at historical land use change in smaller watersheds we would.
Eric Moore: Maybe the our article tracking on it may not be the best way to do it, but looking at some of the CD and you can clear historical data.
Eric Moore: would be good and we're actually on a long island sound project right now looking at at some of these hotspots in historical land use as well, so yeah great question it's super hard and small streams.
Eric Moore: But some of that historical land cover data may have.
Nick Hastings: yeah and Christine you offered up a reference as well in the chat, so I would point that out to Eric.
Christine Hatch: I was just I was signing it for the previous question, because it was the reference he was referring to you from from his presentation, but i'm asking to if he has one for the thermal imagery from the drones that you showed.
Eric Moore: i'm not from that imagery we have some other drone images that that's been published, that I, but I thought, a cranberry bog and Massachusetts not necessarily associated with with this project, but our our drone data is coming out soon.
Nick Hastings: yeah and I actually had a follow up question on the on the drone data so that's timely.
Nick Hastings: You showed some of the thermal imaging the drone for the farmington river and I know it seemed that you did most of your research presented with handheld did you do both did you do try to do some correlation as to how they tracked with with respect to their patterns.
Eric Moore: yeah that that's what's being worked on right now, we had a postdoc who, who did a lot of our drone imagery and we're the PhD students students going back to these sites to try to make those comparisons and this this past summer and next coming summers as well it's coming out.
Nick Hastings: It will be very helpful.
Nick Hastings: Right and we got another reference from Janet they're good.
Eric Moore: Thanks Janet.
Nick Hastings: Right and, finally, Christine said thanks i'm familiar with the tick marks drone flights stick around for a list this presentation and you'll see the adjacent property Nice.
awesome.
Eric Moore: Thank you.
Nick Hastings: Other questions.
Nick Hastings: Okay, great thanks again Eric and i'll pass the baton back off to my compadre Mike for the next introduction.
Mike Apfelbaum: Alright, thanks, Nick so our next presentation is alyssa chase from the University of Massachusetts department of geosciences and she will be presenting on glacial and anthropogenic tales told by a sediment core on its way to becoming a wetland.
Mike Apfelbaum: And alyssa you should be ready to share here.
Mike Apfelbaum: perfect.
Alyssa Chase: Good morning, and welcome to the virtual section meeting of northeastern GSA and wanted to thank you all for coming this morning.
Alyssa Chase: Today we are going to talk about what we can learn about both the geologic and land use history from us soil core and I wanted to say thank you to my co authors one who's here, Christine so thank you very much.
Alyssa Chase: So this study was conducted in conjunction with a restoration plan to restore a retired cranberry bog into the wetland it was before farm began.
Alyssa Chase: The site is located in the beaver dam broke watershed in Plymouth Massachusetts and the groundwater the fuel, so what letter comes from the Plymouth Carver kingston duxbury geographer system and flows generally from west to east.
Alyssa Chase: So a little bit of the site geology as many of you i'm sure familiar.
Alyssa Chase: This area is dominated by the glacial history so just a brief overview of that we had about 23,000 years ago the Wisconsin glacial maximum where.
Alyssa Chase: The ice splits into two lobes and we can see that evidence here, as well as up into the Cape cod bay.
Alyssa Chase: over here.
Alyssa Chase: And then.
Alyssa Chase: About 16,000 years ago the ice retreats from Cape cod and glacial lake Cape cod filled the bay.
Alyssa Chase: And this is where we get our last deposits and well sort of grains near to march because of this, this was around 15,000 to 40,500 years ago.
Alyssa Chase: And then.
Alyssa Chase: clays and low permeability sediment were deposited in the Bay and in the south of the Cape and low lying areas with no outlet accumulated thick pete deposits about 12,000 2000 years to present, which is what we will begin talking about in a minute.
Alyssa Chase: So this area was formed by glacial activity defined by the growth and retreat but multiple large sheets device, as we just talked about.
Alyssa Chase: And as the ice retreated from the area, some of the ice broke off of the main sheet and was then very.
Alyssa Chase: After this, the blocks that were buried, on top of the bedrock melted and course sand and gravel them filled the whole creating a kettle hole and the water in the area is bounded by the bedrock below.
Alyssa Chase: The candle whole process at foothill started about 16,000 to about 9000 years ago and this age death plot here on the upper right hand side came specifically from the site at foothills and shows that pete accumulation slowed down.
Alyssa Chase: So these deep soil course show deposits that have clays from dependent plane deposits overlaying by pete in this kettle hold and above the p there is some anthropogenic layering which I will talk about in a minute.
Alyssa Chase: So the geologic cross section from stunning stone has been modified for this artist's rendering of the substrate.
Alyssa Chase: And this figure shows were specifically wetlands tend to form in this glacial setting on top of either clay or pete and the wetland at foothills is no exception to this this provided the ideal setting in which to grow cranberries which are a native wetteland player.
Alyssa Chase: So for over a century, beginning in 1854 before it was retired in 2015 to marsh farms and what is now foothills preserve or farm for cranberries.
Alyssa Chase: This has substantial impacts on both the geology and the hydrology of the area.
Alyssa Chase: So for those who don't know anything about cranberry farming cranberry farmers put down a layer of sand ones about every three years in order to stimulate growth of the planets.
Alyssa Chase: The sample that was laid down it to martian foothills consists of glacial outlaws from nearby areas which we talked about a little bit earlier.
Alyssa Chase: So, after the sand is pleased agricultural soil builds up on top of it, and this process repeats as farm it continues and what you get them anthropogenic Lee created layering of sand and agricultural soil that looks like this.
Alyssa Chase: So the image on the right here is a light our map of foothills preserved and this quarter that I will be talking about in a minute came from section C 02 right here, where the stars.
Alyssa Chase: and
Alyssa Chase: So this.
Alyssa Chase: So overall, I found that there's about.
Alyssa Chase: 32 centimeters of sanding agricultural soil about pete that fills the kettle hole in this specific spot calculated by adding together the thicknesses of each of the staff and agricultural soil layers in this Court.
Alyssa Chase: And there's an average about 35 centimeters of San and agricultural soil above the pete around the site which causes some problems for restoring the weather and hydrology to the site.
Alyssa Chase: So in the lidar map, you can see how anthropogenic Lee modified this area has been so right here with the laser pointer i'm tracing the main channel of the cranberry farm.
Alyssa Chase: which comes up the top the Northwest side and then comes out the southeast side and then through here, especially through see 02 you can see.
Alyssa Chase: Very linear irrigation ditches which were also created for the farm, which will again become important in a minute.
Alyssa Chase: So without the sand and agricultural soil, there would only be pete in the area which has the low hydraulic conductivity and holds water like a sponge.
Alyssa Chase: The people's onto floodwater which mitigates flooding and can also process and remove excess nutrients and chemicals purifying water, in addition, the pete serves as carbon pricing, because it does not break down plants and release carbon dioxide.
Alyssa Chase: and agricultural soils that were placed in the area by farming processes, then allow water to move much more than P, what happened, naturally.
Alyssa Chase: Not only does the water move more overall, it also moves more horizontally and vertically.
Alyssa Chase: So we found a kh kV value from my core specifically have around 20 for this area, which illustrates this tendency to move horizontally, rather than vertically.
Alyssa Chase: So in this figure, this is shown as an unconfined aquifer because the water is exposed to the atmosphere through the sand and is perched on top of pete.
Alyssa Chase: there's another article for in the area that is confined in the p So if you were to put one parameter in the sand and one of the pete.
Alyssa Chase: The confined to Oxford and the p would have a higher water level than the one in the sand, because it's under much more pressure from groundwater pushing up into the feet, where it cannot move much.
Alyssa Chase: So drainage ditches were created in the area for farming and these ditches provide an outlet for all of the water in the area.
Alyssa Chase: water in the unconfined ockelford that is more susceptible to horizontal flow flows into these ditches and out of the area and water in a confined awkward for in the pete can also escape through these stitches which tries out the peak.
Alyssa Chase: So the results of the addition of these soils and these ditches, then, is that water cannot stay in the area, as well as it did before farming began.
Alyssa Chase: So this means that wetteland plants cannot survive.
Alyssa Chase: And the Auckland plants take over in the area on the newly dried surface and the flood mitigation and water purifying qualities of the area.
Alyssa Chase: Once had are no longer there, so this image on the right is from about five years after the last harvest in the area, and you can see, as it dries out as it has dried out more upland plants have taken over in the area.
Alyssa Chase: So farming also put down layers of fertilizers, pesticides and excess nutrients which, because of these new soils are not able to be removed by the pete.
Alyssa Chase: And can then be mobilized further downstream, which can have negative impacts on the welland plants in the area and plants further down the watershed and into the ocean.
Alyssa Chase: So, in order to look at bubbles of these nutrients we performed an x Ray for us and scan of the Court to see the elemental chemistry, the core.
Alyssa Chase: So on them and on the left, here we have the entirety of the core about to go into the scanner and on the right, we have the core in the scanner and you can see the Little Red laser pointer of where the core is actually being scanned at that time.
Alyssa Chase: So this figure shows lead values versus the depth of the core and you can see clearly where the anthropogenic soils transition into the wetland pete below, as there is almost no lead of the P, but there are high amounts of blood in the anthropogenic soils above.
Alyssa Chase: So this line delineates about where the transition from the anthropogenic soils to the peak is.
Alyssa Chase: And we know that pesticides containing lead arsenic were used in this area up until 1955, so this is indicative of residual pesticides from the cranberry farming 1955 correlates to around 17 centimeters of depth.
Alyssa Chase: But peak use of this pesticide seems to be a little bit before 1955 so with the X Ray for essence data I also sought to demarcate different layers in the anthropogenic soils.
Alyssa Chase: The most indicative element was awesome em which is presented in this figure next to the section of the core it correlates to with high amounts of aws MIA correlating to the agricultural soils and low amounts of aws neon correlating to the sand, so we can see that here very well.
Alyssa Chase: The data was even better at the marketing newsletters than the human eye visual inspection lets us estimate where these layers are, but the elemental score scan is much more accurate at showing them.
Alyssa Chase: And by sending an approximate thickness for layers of greater than one millimeter and knowing that Sam was applied about every three to three and a half years, we were able to approximate the entire time span since farming began on the site and create our each step squad.
Alyssa Chase: So one thing we learned from conducting this analysis was that the layer of anthropogenic soils was too thick to be removed from the site.
Alyssa Chase: And would have to be mixed with the pete below in order to mitigate the hydraulic the hydrological effects of this layer so there will be sufficient water to maintain wetland plants.
Alyssa Chase: And mixing this layers these layers also allowed us to resurface the ancient seed bank, so this photo is from during the restoration and you can see, this pedometer over here the little white.
Alyssa Chase: And that indicates the former land surface, so what is going on here is during the restoration we're mixing up all of the sand in the peat, and that has allowed that area to retain water much better and this area is actually now a lake.
Alyssa Chase: So some of the ecosystem services of wetlands are to capture and store floodwaters improved water quality, by removing excess nutrients and breaking down other potentially harmful compounds.
Alyssa Chase: pot of water and weapons is often anoxic so weapons can store carbon as more plants die and fall into them restoring the site to a wetland also prevents legacy fertilizer from running off and harming areas further down the watershed.
Alyssa Chase: So I wanted to say thank you all for coming and before you all ask me questions I actually have a question for you.
Alyssa Chase: So we found that azam was good indicator of the agricultural soil and this area, but we are not completely sure why so we were wondering does anyone know why was me i'm would be a good indicator of the soil type so again, thank you all for coming and i'll open it up to questions.
Mike Apfelbaum: Thank you alyssa I was gonna ask the same question what's the sickness of the atomium so.
Mike Apfelbaum: it's a good good segue.
Alyssa Chase: yeah we were just looking at all of the different elements that the core scan for and found that that one happens to be the most indicative of the layers lined up.
Mike Apfelbaum: Hopefully you get some some useful tips this point.
Mike Apfelbaum: So you got a couple questions here, showing up.
Mike Apfelbaum: I believe you had one question regarding calculation of your horizontal vertical hydraulic conductivity for Dan siegel, but you can.
Christine Hatch: do that if you don't know the answer.
Alyssa Chase: To Christine.
Christine Hatch: yeah no that's not good.
Christine Hatch: So we actually use the high prop to measure the properties of the of both of the piano soils and the sands and then use the harmonic mean.
Christine Hatch: calculation for the vertical hydraulic conductivity through those layers versus the arithmetic mean for the horizontal conductivity so using the actual thicknesses from the scan.
Great.
Alyssa Chase: and
Alyssa Chase: can lead arsenic ratios for us to estimate the ability of arsenic, out of the system based on known Molar ratio of the pesticide.
Alyssa Chase: We have not yet compared the lead arsenic ratios.
Alyssa Chase: But I would imagine, so if we know the amount of the pesticide at why.
Mike Apfelbaum: There was one question before that, regarding the unit in the concentrations of the atomium.
Alyssa Chase: Honestly i'm not sure Christine Do you know what the scanner measures.
Christine Hatch: I can't remember no i'm sorry.
Mike Apfelbaum: What was the resolution of the scanner was from a spatial depth interval.
Alyssa Chase: It was two millimeters.
Christine Hatch: point to.
point.
Mike Apfelbaum: So let's get up there.
Alyssa Chase: yeah we actually did a much lower resolution scan of another Courtney area and you really could not see very many layers as well, so the higher resolution was definitely very important for this analysis as well, because I.
Mike Apfelbaum: think it was one question regarding was a scanner next rf I believe that, yes, that was the case.
Alyssa Chase: Oh thanks Bob yes.
Christine Hatch: Bob says he thinks the Osman units are just counts Bob I want to know what you why you think it was me i'm showing up in the agricultural soils.
You must have an idea.
Bob Newton: I have no idea.
Bob Newton: it's a great question though and i'm.
Bob Newton: Thinking about it.
Christine Hatch: it's you know it's really weird because there are other things that show up somewhat in the you know that.
Christine Hatch: tend to pin to the organics but they asked me when was the one that doesn't show up at all in the pete and also pins to the organics and so it's really clear for those agricultural soils.
Mike Apfelbaum: Great any other questions.
Mike Apfelbaum: For alyssa.
Christine Hatch: We might have to send us off she's gonna go.
Christine Hatch: and
Christine Hatch: For us soccer.
Alyssa Chase: A busy morning yeah.
Mike Apfelbaum: daylight savings to.
know.
Nick Hastings: So don weighed in on the the admin.
Mike Apfelbaum: Oh yeah.
Nick Hastings: looks like in the shadows off with at least some thoughts they're good.
Christine Hatch: yeah thanks john appreciate that yeah.
Mike Apfelbaum: Any other questions for alyssa.
Mike Apfelbaum: Well, great.
Alyssa Chase: Thank you.
Mike Apfelbaum: Thank you and good luck.
Thanks to research.
Nick Hastings: Some virtual Applause
Nick Hastings: All right, well, moving on our next up is Anna and I apologize for mispronouncing it labeled.
Nick Hastings: From the geology department at middlebury and she's going to be presenting on behalf of our team testing for evidence of subsurface phosphorus transport to a small lake in northwestern per month, so take it away.
Anna Loewald (she/her): Thank you very much.
Anna Loewald (she/her): Sorry i'm just trying to minimize.
Anna Loewald (she/her): People.
Anna Loewald (she/her): Okay, thank you all for listening to these talks, today I will be taking you through some of the work that I have been doing for my senior thesis at middlebury.
Anna Loewald (she/her): And I would also like to acknowledge my co authors and advisors P Ryan and john Kim.
Anna Loewald (she/her): As you can see, on the right here, this is a photo of late Karma and you can see, on the top this kind of Green film and that are those are algal blooms and that's what i'll be talking about a little bit today.
Anna Loewald (she/her): So i'll be taking you through the study area of late Karma and then the issue with algal blooms they're currently then our hypothesis of why these algorithms are continuing.
Anna Loewald (she/her): will take you through some methods and some data, including some PCA parts and green size analysis and then takeaways and next steps and leave time for questions at the end.
Anna Loewald (she/her): Here is the study area that we were looking at, as you can see, it is in the North Western portion of Vermont actually bordering Canada here.
Anna Loewald (she/her): And you can see, this Green outline is the late Karma watershed that we will be looking at on this geologic map on the right, and you can see that the majority of the watershed is within fairfield Paul information which is made up of political court sites.
Anna Loewald (she/her): So for several decades now, there have been there's been a problem of algal blooms at lake Karma this is due to high phosphorus concentrations as phosphorus is eliminating nutrient for algal blooms these cause late summer algal blooms, and these are very.
Anna Loewald (she/her): very bad for the environment as they lead to reduction in the dissolved oxygen in the lake this is toxic to biologic life leads and leads to a reduction in biodiversity in the link.
Anna Loewald (she/her): It also leads to reduction of water clarity heavy aquatic plant growth and it's toxic to humans.
Anna Loewald (she/her): So it is historically believe that phosphorus is not readily transported by groundwater, this is because phosphorus is assumed to be particularly so it would move much more slowly through the subsurface.
Anna Loewald (she/her): And there are many complex soil processes that can take place to either prevent or encourage groundwater transport phosphorus.
Anna Loewald (she/her): These include the iron read off cycle and saturation levels so natural system it's believed that because phosphorus is articulate and it's not saturated and it wouldn't be able to be transported via groundwater, but with.
Anna Loewald (she/her): The legacy application of phosphorus on agricultural lands, or perhaps the natural high natural source of phosphorus from ground up sediments phosphorus could.
Anna Loewald (she/her): go over the saturation level of the sediment and potentially be transported via groundwater and we have seen that, with this phosphorus saturation that dissolve officers can in fact be mobilized and transported in the subsurface via groundwater many on that are richer has found.
Anna Loewald (she/her): So due to this legacy problem of algal blooms at lake Karma there was a 2018 DL and a 2016 implementation plan done on like Karma However, these focused primarily on watershed tributary transport.
Anna Loewald (she/her): and surface water and nutrient transport, as you can see here in this pie chart the majority of the.
Anna Loewald (she/her): source of this phosphorus was believed to be coming from these watershed tributaries specifically from agricultural pasture and grass and row crop fields.
Anna Loewald (she/her): So you can see, this is just a table showing what you can see in this pie chart you can see the kilograms per year that's believed to be coming from each of these sources in the lake Karma watershed.
Anna Loewald (she/her): So, despite the implementation of phosphorus transport reducing methods at lake Karma the effects of eutrophication, have not decreased these transport reducing methods include switching from corn to hay fields.
Anna Loewald (she/her): Decreasing the amount of fertilizer on these lands and management practices like drainage ditches on roads.
Anna Loewald (she/her): So I have our hypothesis is that groundwater may play a strong role in nutrient transport into the lake leading to the continued algal blooms at late Karma, and this would be in addition to run off from anthropogenic sources.
Anna Loewald (she/her): So i'll take you some through the methods of how we found of how we got our data that i'll be showing you today, and this was done.
Anna Loewald (she/her): As part of a study to monitor a larger study to monitor shallow groundwater and the lake Karma watershed so we drilled course with this GEO probe hydraulic punch that you can see, to the right here.
Anna Loewald (she/her): This extracted these sediment course that were about 20 feet long.
Anna Loewald (she/her): And then, after we drilled these these cores wells were installed and these wells are being continually sampled as part of this larger study.
Anna Loewald (she/her): Then we did some lab analysis on the course there are nine course in total, we found the water table of the within the course and then we sampled in the beta and the unsaturated zone and the frantic.
Anna Loewald (she/her): saturated zone.
Anna Loewald (she/her): So, then, we use this Malik method of week extraction using dilute sulfuric acid, and the reason we did this was to get the environmentally available elements in the sediments.
Anna Loewald (she/her): So essentially what groundwater would extract while it was flowing through these sentiments and then could potentially bring into the way.
Anna Loewald (she/her): We did this by drawing sediments and then diluting them with us off here acid and filtering them once.
Anna Loewald (she/her): And then diluting them once again with some de Ionized water and in order to get them into the pH range of the ICP Ms so we're going to use and filtering them once again so that we only got the dissolved portion.
Anna Loewald (she/her): Really simon's so, then the they were analyzed on the ICP Ms and via iron chromatography we analyze four major elements, including phosphorus sodium calcium iron aluminum etc, and also some trace elements, including chromium cobalt nickel zinc or say.
Anna Loewald (she/her): Then we also did some grain size analysis which we diluted the sentiments with a 3% Taleban disperse and analyze for brain size.
Anna Loewald (she/her): So.
Anna Loewald (she/her): Here I will be.
Anna Loewald (she/her): I will be showing our literature values versus a couple different other literature values for extractable phosphorus in sediments so our study here is this lowell that all and we have three other studies are comparing to today.
Anna Loewald (she/her): And the have they all have a range of soil types, the most important thing that we're looking at here is the fertilization on the direct fertilization on to these settlements.
Anna Loewald (she/her): With my sentiments here, there was no direct fertilization, and in the other ones, there was either a mineral or a maneuver fertilization onto the settlements.
Anna Loewald (she/her): So all of these settlements, all of these phosphorus values were extracted with the same mailing method of using sulfuric acid, and as you can see our values are in the same order of magnitude, as all of these directly fertilized enriched.
Anna Loewald (she/her): sediments so this shows us that there is a relatively high reservoir of environmentally available phosphorus in the sediments that could then be transported to the lake via groundwater.
Anna Loewald (she/her): So, now that we know that there is an available reservoir phosphorus of unknown origin, we wanted to project how this reservoir could then impact the way.
Anna Loewald (she/her): We did this by calculating different scenarios of what percent groundwater could be contributing to the lake water budget, so now i'll take you through how we calculated these different scenarios.
Anna Loewald (she/her): So, first we use one meter precipitation per year, which was we got from based off of local precipitation in the area.
Anna Loewald (she/her): multiply this by the area of the lake or my watershed to get the precipitation per year and the light current watershed then we converted this to the leaders of precipitation per year.
Anna Loewald (she/her): And now we get to our scenarios and we looked at different literature values of potential ground water percent as part of the lake water budget.
Anna Loewald (she/her): We found a very large range of potential brown water percent all the way from 10 to 90% so from this, we decided to use the scenarios of 2550 and 75% to get a wide range of the potential amount of groundwater, that is being.
Anna Loewald (she/her): brought into the lake.
Anna Loewald (she/her): So this gets us these scenarios of brown water flow into lake Karma in leaders per year, as you can see here.
Anna Loewald (she/her): We then multiply this by 10 and 20 ppb of phosphorus we did this because the average from the groundwater wells in the area, or about 17 ppb of phosphorus.
Anna Loewald (she/her): So we decided to take lower range and a higher range of potential concentrations of phosphorus in this groundwater.
Anna Loewald (she/her): This gave us the milligrams of phosphorus and put it annually, and then we just converted this to be kilograms per year of phosphorus transported via groundwater into the lake.
Anna Loewald (she/her): And then i'm just putting up this table once again from the tm DL which shows, also the kilograms per year of phosphorus loading from different sources so as you can see.
Anna Loewald (she/her): Our lowest scenario actually has about 13% of the goal of reduction in the tm DL and then our highest scenario has 76% of this goal.
Anna Loewald (she/her): So we can see here that the potential phosphorus being transported via groundwater into the lake.
Anna Loewald (she/her): and on about the same order of magnitude, if not higher than a lot of the sources that are being being considered in the temp DL.
Anna Loewald (she/her): However, these groundwater sources are currently not being considered as part of that, and neither are they being considered as part of the implementation plan.
Anna Loewald (she/her): So that i'll take you through this principal component analysis that we did with the samples.
Anna Loewald (she/her): So this first plot, you can see here has phosphorus plotted with different oxides that phosphate most readily absorbs to do, do I an eye on exchange on the to these positively charged mineral surfaces.
Anna Loewald (she/her): what's interesting here is that phosphorus doesn't plot very closely with iron, which is what we kind of seems counterintuitive as iron is to be considered a strong control on.
Anna Loewald (she/her): On phosphorus availability in sediments due to the iron redux cycle so potentially so if there isn't any fair phosphates option and it isn't liberated first with this extraction that we did or there is no real correlation between phosphorus and iron hydroxide hydroxide in this system.
Anna Loewald (she/her): But it's interesting as you can see that manganese actually pots very closely with phosphorus and so this indicates that potentially manganese hydroxide are solving some of the phosphorus and have a stronger control on the environmentally available phosphorus in the system.
Anna Loewald (she/her): This next plot that i'm showing you adds in sodium and calcium into the PCA and you can see here that sodium also pots very closely with.
Anna Loewald (she/her): phosphorus but it doesn't plot very closely with calcium, so this may indicate that the sodium and phosphorus are of natural sources, instead of anthropogenic sources like water softener which you would see sodium and calcium probably applauding closer together.
Anna Loewald (she/her): Something to note that is that sodium is often released in relatively high amounts from exchange sites on plays and micah's insulates and delights.
Anna Loewald (she/her): And what we found doing some grain size analysis was that our phosphorus is negatively relatively never negatively correlated with me and green size, which means that there.
Anna Loewald (she/her): seems to be a higher correlation between phosphorus and the amount of phosphorus and the amount of clay minerals in.
Anna Loewald (she/her): In our sediments so this means that potentially the sodium and the phosphorus could be absorbed onto the clay exchange sites.
Anna Loewald (she/her): Which.
Anna Loewald (she/her): yeah in the sediment matrix so this could be more of a natural source of phosphorus and sodium than anthropogenic.
Anna Loewald (she/her): So some takeaways and next steps that all share with you.
Anna Loewald (she/her): Or that we have found that there is like the a reservoir of phosphorus in the sub service and this reservoir of phosphorus is environmentally available, and this is likely, contributing to the continued presence of algal blooms via groundwater transportation into late Karma.
Anna Loewald (she/her): And the source of this reservoir is still unknown, so we are continuing to try to figure out if it could be more of a natural source of phosphorus from the ground up sediments in the subsurface or if it could be more of an anthropogenic source from the agricultural fields around.
Anna Loewald (she/her): lake or my.
Anna Loewald (she/her): So what we want to do next is try to quantify the groundwater phosphorus input we want to do this.
Anna Loewald (she/her): More specifically, than the scenario, so that it can be added into the mdm implementation plan and then be better assessed by having a better idea of actually how much ground water is flowing into the lake and how much phosphorus described water is then transporting transporting.
Anna Loewald (she/her): We hope that the results of the study will be applicable to other lakes in the region, specifically like slightly Karma that are you trophy or meza terrific within close basins, an example of this is like your coin in Vermont, as you can see in this map here.
Anna Loewald (she/her): Thank you very much for listening to this talk, if you have any questions i'd be happy to answer, along with P, Brian and john Kim.
Nick Hastings: Thanks Anna those great folks want to put questions in the chat or raise your hand feel free.
Nick Hastings: i'll ask one while you're thinking about it.
Nick Hastings: So you mentioned earlier on, that there were some best practices around the agricultural inputs in the tributaries which you know seem to be a tributaries at least from their table it seems to be a made the the major contributor, by a large margin orders of magnitude.
Nick Hastings: How long have those best management practices been in play, and was there I don't know it was part of your scope to look at the the timeframe over which those were been done, whether there was any.
Nick Hastings: Any benefit from that or whether it just was pretty status quo, in which case you're you're groundwater input becomes even more Aha ish shall I say.
Anna Loewald (she/her): yeah um so I know that some of the best practices have started to be put in place since 2016 i'm not sure before them.
Anna Loewald (she/her): It was interesting to see, there are some.
Anna Loewald (she/her): moderating in the lake itself from the vm and they found that there wasn't a.
Anna Loewald (she/her): decrease in phosphorus at the surface of the lake there was at the bottom of the lake because they implemented an area like a lake bottom area so that was in order to keep the phosphorus served on to the iron.
Anna Loewald (she/her): During the summer months so that did decrease the amount of phosphorus that was being seen at the bottom of the lake but there wasn't a decrease at the top of the lake, which means that it makes us think that there probably is still input via groundwater.
Nick Hastings: Good thanks some folks are adding to the chat I can read them or, if you want to see them that's fine either way.
Anna Loewald (she/her): i'm sure see.
Nick Hastings: So Helen asks is the scalable to lake champlain oh God help you or are there parameters other parameters to different, including the vast depth affliction.
Anna Loewald (she/her): Yes, um I think it would be.
Anna Loewald (she/her): i'm not 100% sure I think there are a lot of other parameters to lake champlain due to its size and the depth of it and that could be very difficult to try to figure out the amount of groundwater flow potentially going into lake champlain.
Anna Loewald (she/her): But potentially that would be really an interesting thing to look into more.
Nick Hastings: And christine's asks are there chemical means, such as isotopes for distinguishing between phosphorus sources.
Anna Loewald (she/her): um i'm not sure I might throw that to my co author and advisor pete Ryan, if he has something to Sam.
Anna Loewald (she/her): you're muted.
Nick Hastings: I was just gonna say he's either think.
Peter Ryan (he/him): I got I made it so you could see me but not hear me.
Peter Ryan (he/him): You would think i'd be getting better at this phosphorus only has one isotope which, unlike nitrogen you know you can use isotopes to trace nitrogen, phosphorus is just 31 it's like arsenic.
Peter Ryan (he/him): Tragically, lacking and stable isotopes.
Nick Hastings: yeah someone threw that up in the chat to Daniel you have your hand raised.
Daniel Brabander: Thank you good morning everyone and Anna what a great talk, I really appreciate your study a tongue.
Daniel Brabander: I want to look at the connections between mass balance in your system and your principal component analysis and I think there's a tendency to.
Daniel Brabander: get excited when you see a correlation on a PCA like between your manganese and your phosphorus and yet from a mass balanced perspective there's much more iron in your system, then manganese and I wonder if you put that constraint on to it what's the relative driver here.
Daniel Brabander: How much how much more iron is there in the system than the manganese and thank you so much.
Anna Loewald (she/her): Thank you for your question, that is a great question I have personally haven't thought about that as much I don't know if he has something to say on that.
Peter Ryan (he/him): yeah that's a great question I was just looking at the data as as Anna was giving the talk and there's at least 10 times as much environmentally available iron.
Peter Ryan (he/him): So, and given the variable sources of iron not just iron oxide, but maybe a little bit might dissolve at a chloride Derby.
Peter Ryan (he/him): yeah President other sites so it'd be interesting to think about trying to adjust for the relative abundance of those in this kind of analysis I think that's a great consideration.
Nick Hastings: Other questions.
Nick Hastings: Right, if not well, thank you very much again in a great talk and I will pass the baton once again off to Mike for the next talk oh there's one hand raised first hold on Christine.
Mike Apfelbaum: We got time.
Christine Hatch: For photo they're just applause, but I just wanted to say really great presentation, it was very thorough and really well presented so well done.
Nick Hastings: It was the sideways things.
Mike Apfelbaum: Alright, so our last presentation before this morning's break is Erica high willer and she is from Kent State University and she will be presenting on how road salt contaminates aquifers, a guide for policy in management.
Mike Apfelbaum: This picture.
Erika Hiwiller: Also, not very familiar with zoom so this one's earlier trying to do it again.
Erika Hiwiller: room can everyone see.
Mike Apfelbaum: Yes.
Erika Hiwiller: Yes, great perfect Thank you so yes, I am a second year masters student at Kent State University.
Erika Hiwiller: And so i'm going to be telling you a little bit about my project that i'm currently working on which involves how result contaminates aquifers.
Erika Hiwiller: and using different parameters specifically what i'm looking into is typography and heterogeneity and how those different systems might change the way that you would create and craft policy in your area, specifically for road salt.
Erika Hiwiller: And so first i'm going to go into just a little bit of the background of how we're doing different things, and how we came to this research and picking the parameters and picking.
Erika Hiwiller: analyses and so.
Erika Hiwiller: The first thing is looking into how climate change affects this and that's going to be one of the primary ways that we're analyzing the results.
Erika Hiwiller: And so i'll go more in depth into that in a minute, but looking into how climate change will increase precipitation events in the winter, and so you can see, by this graphic in the winter.
Erika Hiwiller: Where we're expecting a higher amount of precipitation change and so every time that precipitation is increasing or precipitation events are increasing, where it's an opportunity for Roosevelt to be transported into the subsurface and also an opportunity for.
Erika Hiwiller: result to be reapplied and so going into that looking into extreme versions of precipitation events of this combination of not only increasing precipitation events themselves but also increasing.
Erika Hiwiller: The frequency of them, so this is a little blurry how it transferred over but i'm just looking into this increase in extreme precipitation events and so just basically setting the stage for how this is going to become an important discussion going forward.
Erika Hiwiller: saying what this is just an example of average temperature trends increasing just specifically in February and so basically just trying to set the stage for how.
Erika Hiwiller: roadside application is going to be further magnified due to climate change, so it's going to be magnified both from extreme weather events and the change in frequency of temperature oscillations.
Erika Hiwiller: So a storm events increase, but the intensity and frequency and there's just more opportunity for road salt, to be flushed from roadways.
Erika Hiwiller: And so, changing the frequency of temperature oscillation means an increase in freestyle cycles and potentially an increase in application and just possibilities for our GEO environments to be contaminated by the salt.
Erika Hiwiller: And so, basically looking into why does that matter so each year means have tons of road solder dumped in the highways, due to its cost effectiveness and efficiency and so roots old is very good at what it does and it's also a relatively cheap.
Erika Hiwiller: We started relying on it post World War Two as we began to increase our use of cars and impervious surface ways and this need for safety came about.
Erika Hiwiller: The road so has some negative impacts, specifically on vegetation aquatic life and human health and so certain vegetation, especially on roadways cannot survive with this informative.
Erika Hiwiller: in flux of salt into their system and then fresh water aquatic organisms also rely on their water source having low amounts of soap.
Erika Hiwiller: And then it can be detrimental for human beings, so if the sodium makes it through the system, it can put humans at risk for hypertension.
Erika Hiwiller: And also just in general are drinking water becoming more and more salty is not the best for anyone, no one wants to taste salty drinking water.
Erika Hiwiller: Whenever they're opening up their caps and the regulation of roots out very state by state there's some that have extensive studies and understanding the road so use and trying to think about legislation of it when some put some impact.
Erika Hiwiller: Some policy into place and others have little to no regulations In most places seem to have adopted a policy, known as the bear pavement policy which.
Erika Hiwiller: Thinking about it whenever I first looked at it was like his little salt as possible but it's actually to me was counterintuitive it's keeping as little as often as possible and so having as little.
Erika Hiwiller: ice on the road is absolutely possible, preferably a bear payment so lots and lots of salt in order to make that happen.
Erika Hiwiller: And so there's definitely lots of places that are looking into alternatives some super fun like I know Wisconsin has been trying to make cheese brian's in order to come up with an alternative to their salt.
Erika Hiwiller: my hometown of less sunbury pumps Pennsylvania has been experimenting with cranberry juice.
Erika Hiwiller: But there's already some preliminary studies that have coming out that it's having some negative wildlife impacts, especially with the mayfly.
Erika Hiwiller: And then there's other places, looking into using oil brian's for the oil brands can contain radioactive materials and cause cancer and create a whole new problem.
Erika Hiwiller: And so, at the moment alternatives aren't something that are able to be use said they're largely untested even more unregulated and so salts really the only good option at the moment, but even then we're still need to look into how what effect it's having.
Erika Hiwiller: And so, looking into creating a computational model, which is what my research is heavily focused on.
Erika Hiwiller: So other people have discovered that climate change, population growth urbanization are resulting in this increased reliance on road, so it is a DEA agent.
Erika Hiwiller: But concentrations of roads are aren't just found in the winter they're also found in the summer months so that begs the question of why.
Erika Hiwiller: So understanding how is it transported at the base and scale and what parameters are having a role, and not only these concentrations being found in the winter as we'd expect.
Erika Hiwiller: But having a residence time in the awful for until it so they're not contributed to base flow until the summer and so why is that having that effect and so.
Erika Hiwiller: i'm.
Erika Hiwiller: Basically, looking into how we can better frame policies for it specific do environment, and so this specific study by Sarah ledford and Laura lots looking at on the left, how does arbiters of real data that were discovered and then projecting the next year of model data.
Erika Hiwiller: Our model highly is.
Erika Hiwiller: i'm looking at how.
Erika Hiwiller: To explain um basically these values and trying to validate our model by having similar to what is found in some real life studies, this is just one example of the different studies that we looked at.
Erika Hiwiller: And so, basically from there, looking into the parameters of typography and heterogeneity and how those specific.
Erika Hiwiller: parameters might play a role in this transport and how it might be having effect on the residents time.
Erika Hiwiller: of Florida, and the subsurface and and not being released until the summer months into base flow and what exactly it's doing it, and so, how a combination of the specific frequency abroad so applications and this.
Erika Hiwiller: How the subsurface hydraulic architecture could cause Roosevelt to be stored for large periods of time.
Erika Hiwiller: So another thing just talking about background about how we're creating this model, our typography is highly based off at tesla.
Erika Hiwiller: And so topography of basically to flow with whenever the part of your mouth for falls a so I don't know curve.
Erika Hiwiller: As with most things I would we often say, while we're working on things that most thing in the world are so I encourage nothing.
Erika Hiwiller: is rarely this perfect linear system when we're looking at geology and so we're using that to try to represent these real world mountains and valleys and also, most importantly, creating these local intermediate and regional flow cells and how our.
Erika Hiwiller: World salt transport would be different, depending on if you're in a system that's dominated by local flow versus regional flow.
Erika Hiwiller: And the second scenario we're looking at is how a heterogeneous layer cake with lenses and play role So how do different layers within an awful for have different hydraulic conductivity influences transporter contaminants.
Erika Hiwiller: And so, these complicated layering leaving for complex will pass for a contaminant to follow so How does that affect residents time and its eventual arrival to base flow.
Erika Hiwiller: Once soul enters the system, how long is it staying in the system, and how are these layers contributing to that residents time in it.
Erika Hiwiller: And so, that is the background of and then going into what i'm specifically doing so my research objectives are to use computational modeling to determine how.
Erika Hiwiller: Does the water table topography variation affect the transport of road So how do heterogeneous lenses with different hydraulic conductivity influences transport of road salt.
Erika Hiwiller: How does the climate change, how does the change in frequency loading of road salt due to climate change influence contaminate transport and then how can we use these results in order to make suggestions for policymakers regarding roads.
Erika Hiwiller: And so the scenario is being tested I am using for topography, we are creating different geographies, with an average base case low and high end members of basically low and high end amplitude values for the subtle subtle curve.
Erika Hiwiller: And so we have a five by five matrix of these amplitude values varying from dominating of regional to local flow cells and creating either more or less local flow cells by.
Erika Hiwiller: Changing how the systems are dominated and then for heterogeneity we have two cases so clay and sand layers with lenders so first creating.
Erika Hiwiller: Essentially, a sand domain, that would have clay lenses in it and then for the second case, creating a.
Erika Hiwiller: clay domain with sand lenses and then having a three by three matrix of amplitude values to test for that as well, so overall running 47 simulations or 4343 simulations of.
Erika Hiwiller: Different typography and heterogeneity values and analyzing them each in three different ways.
Erika Hiwiller: And so, each scenarios analyze based off a pastel build up, which I will show you the analytical function we're using an order to create that password build up.
Erika Hiwiller: future changes and seasonal loading due to climate change, and so, how we can change that analytical function to have different input values over time.
Erika Hiwiller: And then, finally, the flushing time, so if we were just after we have the salt build up in the offer how long if we were to stop utilizing roots all right, the second how long would it take for it to completely flushed out of the system, and so, each one of these.
Erika Hiwiller: scenarios from the three matrices will be analyzed by each of these results.
Erika Hiwiller: Are scenarios, and so this is just a cross sectional diagram of how very basic looking into how we're crafting the specific aquifer.
Erika Hiwiller: Of a basically hypothetical idealized tank offer, and so we have the bottom boundary here is 10 kilometers in length.
Erika Hiwiller: And the vertical exaggeration is about 20, because if we wouldn't have that you just be looking at a flat line, and so we have no full boundaries on the right and left creating this tank domain and then here what you're looking at is.
Erika Hiwiller: How we're able to change typography so this almost flat is if there is very we have amplitude it's very, very low for both regional and local flow and our final total equation.
Erika Hiwiller: And then, this dashed line is with only regional amplitude in place, and so we have over original value of about 13 here for our high case so we're able to create these boundaries and the flow cells that are present and.
Erika Hiwiller: The first seven kilometers are going to as we change the amplitude represent more mountainous regions, and the second, or the last three set of kilometers would represent a flatter more URBAN.
Erika Hiwiller: area.
Erika Hiwiller: And so here is the 2d cross section that we're currently working on 400 Jane is a layer cake with lenses and so you can see here we're changing.
Erika Hiwiller: The top boundaries have changed just for the purpose of showing how we're able to change these typography variations even more.
Erika Hiwiller: The dash line here represents very immediate case with a media and regional and local and place and the sick dark line represents only local flow cells in place so we're creating seven.
Erika Hiwiller: Local flow cells over the seven kilometers and so through the system we're able to, in this case, represent a sound domain with clay lenses and then these empty lenses can be used to change or utilize.
Erika Hiwiller: leaky.
Erika Hiwiller: SIS layers and so we're able to change and manipulate the system to basically whatever parameters are in place for whatever system that we want in order to show.
Erika Hiwiller: Thank you so and then we're also establishing.
Erika Hiwiller: Road locations so let's talk a little bit faster so by doing this, the location of road cells were considered bio how we put our roads to try to have half on recharge boundaries half on discharge boundaries.
Erika Hiwiller: And then road density between mountainous and rural locations and so each one's about 10 meters in length and each of those represent our input.
Erika Hiwiller: And so, this area, you can see, local flow cell and then here, you can see, the regional flow cell being developed.
Erika Hiwiller: Until also we have locations of wells that were used for analyzing.
Erika Hiwiller: And so the regional recharge wells local discharge well local recharge well regional discharge well in a river boundary.
Erika Hiwiller: order to analyze how much is actually exiting the system and also the River boundary that is actually created by our model were able to analyze as well, and at all aids us and preparing comparing it to other studies that have been done.
Erika Hiwiller: And so, this is the analytical function that we're utilizing in order to show roads all input.
Erika Hiwiller: And so it's developed Basically, this is multiplied by 60 volts per meter cubed and so over 360 days for the purpose of this study.
Erika Hiwiller: We have the absolute highest input of about 60 miles per meter cube at during what would be considered to us about January.
Erika Hiwiller: Slowly increasing and salt build up and then decreasing over time, and this is a function that we can use to change to have basically any inputs, over time, and so this is just two years of the inputs.
Erika Hiwiller: And so the computational equations that we use for the groundwater equations to solve for flow adoption dispersion dissolve for transport, and then we develop this topography equation based off of Center sort of equations in order to alter the typography and the system.
Erika Hiwiller: And so.
Is it going to let me.
Erika Hiwiller: Trying to start there we go Okay, so this is just an example of shun five years transport system just between.
Erika Hiwiller: are more median topography versus a very flat system and just how transport changes over just five years of these inputs.
Erika Hiwiller: It takes a very long time to create these animations I tried to make one longer for you all but.
Erika Hiwiller: Five years was is good, as it was getting so just a quick look at some of the results and breakthrough curves that we're getting and so after 30 years we saw the salt build up in the River REACH.
Erika Hiwiller: 330 milligrams per liter and the entire domain reached about 319 which, if you remember from the paper.
Erika Hiwiller: That we were looking at for puzzlement or data, it is very close to those results and then interestingly, looking at how different.
Erika Hiwiller: Regional versus local flow cells can be changed and how they're having such an effect, so the green line here, showing local a discharge well and how high those values can get compared to the regional flow cells, which are having much slower.
Erika Hiwiller: So still very high still much higher than the EPA limit but not.
Erika Hiwiller: over double for the local facilities is extremely high value for salt, to be found in a system and so that would readily change how you would be wanting to do your policy based off of that and so kind of rushed through it a little bit sorry.
Erika Hiwiller: i'm not sure how to end.
Erika Hiwiller: Thank you.
Mike Apfelbaum: All right, you got a lot of questions in the chat so.
Erika Hiwiller: I kept seeing the pop up i'm.
Mike Apfelbaum: The first one.
Mike Apfelbaum: I think it just sort of some paper references, I know I don't know if don if you're on if you wanted to actually me about backup to.
Mike Apfelbaum: there's a question regarding precipitation can be more in the form of rain in the future, higher temperatures.
Mike Apfelbaum: Speak to me.
Mike Apfelbaum: To the precept you know scenarios, you were still based or was it actually you know consideration of brain as well.
Erika Hiwiller: yeah definitely right brains going to transport, just as much so, even if we have these oscillations so as the temperature dips down below freezing we'd have snow in the depths backup we'd have rain.
Erika Hiwiller: we're still going to have salting and that would actually increase that's the seasonal oscillations that I was trying to describe.
Great.
and
Mike Apfelbaum: Another sort of thought provoking comment from Dan siegel just with respect to some some you know, looking at fluoridated water as a mass balance check.
Erika Hiwiller: I don't see that one.
Mike Apfelbaum: Pretty far up there, and they have to scroll up a little bit.
Mike Apfelbaum: i'll try and summarize.
Mike Apfelbaum: It looks like don are you on.
Donald Siegel: yeah yeah man.
Mike Apfelbaum: Maybe you wanna.
Donald Siegel: share a couple questions it's a nice talk.
Donald Siegel: let's just tossed out to all everyone who's listening at Syracuse I discovered that fluoride has peaks to come and go and.
Donald Siegel: it's probably from fluoridated water getting out through storm drains and i've been trying to get my own well i'm retired now but folks at Syracuse to look at this as a potential.
Donald Siegel: Research Project to do a mass balance on fluoride which would provide potentially an independent way of figuring how much leakage is coming from infrastructure in places.
Donald Siegel: Where you know you have fluoride in the water, but I have other questions on the modeling feel I looked at your cross sections.
Donald Siegel: And if the if the vertical exaggerations twentyfold you're looking at a vertical.
Donald Siegel: depth, I was about 500 meters or more depending on where you are in your system, and that would intersect almost certainly natural salinity of depth, so one thing you need to think about is how you're going to parse out natural salinity versus not.
Donald Siegel: If you haven't thought of that, and the second is that.
Donald Siegel: In all honesty, the pulses you showed moving along like that's didn't look like what I would expect given site transport using effective dispersion so.
Donald Siegel: I don't know what kind of code using but something might want to check out, you know i've seen a lot of models of sight, transport and.
Donald Siegel: and solve transport.
Donald Siegel: You know it's pretty topical and and seeing these things go vertically down so far.
Donald Siegel: With the scenario that you propose seems.
Donald Siegel: Pretty unlikely to me, unless the salt has such a huge density it's just.
Erika Hiwiller: yeah This is like 20 in depth, it is not 500.
Donald Siegel: Okay, so then check your vertical exaggeration thing.
Donald Siegel: Okay, because you know it's 10 kilometers long and you and I looked at the size of that and it said so, if at scale 20 times you know it's.
Erika Hiwiller: it's pretty good yeah it's probably just my it's pretty.
Erika Hiwiller: Good, but it is it only goes 120 in depth it's not going 500.
Erika Hiwiller: Okay into the system so sorry about that I vertical I just meant that it's we're expanding that line 20 times so that we can see it.
Donald Siegel: Better right right but.
Donald Siegel: Right, but that would be.
Donald Siegel: If we're at scale would be a little pancake right, and so you have vertical exaggerated, but.
Donald Siegel: But so you try to look at the bottom scale to what, if I were to expand that says how how how high, that is.
Donald Siegel: What would actually be.
Erika Hiwiller: So I can change yeah that's just.
Erika Hiwiller: My diagram being but the actual models.
Donald Siegel: Only goes 120 what code, did you use.
Erika Hiwiller: i'm using console multi physics.
Okay.
Mike Apfelbaum: And that's about 1005 so just go to the break but one last question was you know regarding I was just scrolling through here, what about looking its use of sand as a road saw alternative.
Erika Hiwiller: it's definitely a great idea I haven't looked into it, that much to know exactly if it's a great alternative or not.
Erika Hiwiller: But it's definitely a good idea.
Erika Hiwiller: messy.
Yes.
Mike Apfelbaum: As its own complications from sedimentation.
Erika Hiwiller: yeah it seems like nothing's perfect.
yep.
Nick Hastings: Well, great I think we're up to the break and appreciate everyone's attention up to this point go get some more caffeine we'll regroup at 1015.
Mike Apfelbaum: Good.
Nick Hastings: Alright, so welcome back everyone.
Nick Hastings: As you can probably tell john Kim is up next from the Vermont.
Nick Hastings: geological survey and he'll be giving a talk on building a 3D conceptual site model for the pathos contaminated fractured rock aquifer beneath the Rutland southern Vermont regional airport so go ahead john.
Jon.Kim: Well, the first thing I like to do is acknowledge my co author speaker Ryan from middlebury.
Mike Apfelbaum: college.
Jon.Kim: kids Cup is from.
Jon.Kim: University of Vermont ED Romano is from suny plattsburgh and Julia boils awesome from the Vermont geological survey.
Jon.Kim: So back in 2018 it started out with five wells in around the Rutland Vermont a regional airport were found to be contaminated with a P Fos are burned poly slo i'll kill substances which are substances that were derived from the testing of.
Jon.Kim: firefighting foams, to fight aircraft fires that there were there were used tested every year over about 30 years.
Jon.Kim: If you've never seen any of this going on, so this isn't I got to watch the 2019 tests after they found the first.
Jon.Kim: contaminated wells, and now in order to prevent everything from going on the ground, there are tops moats backstops barriers all the form is caught but anyway to test the trucks, you need to test nozzles on the trucks and also how is this coming from reservoirs for the.
Jon.Kim: For the firefighting phones, so I just three this audience SPF always a common one that's eight eight carbons 15 floridians and a box will group.
Jon.Kim: I pfs is another on pfa check say which actually is excellent, I like that six carbons there are 21 other people's compounds that are tested for that we have access to also.
Jon.Kim: This is just a theme transport diagram I made this for bennington Vermont where you can put people into the air.
Jon.Kim: from factories that I temperature and heavy rain down on the ground, but in this case it's simpler we actually have application to a valid surface over decades or in a couple of sentences using it for aircraft fires.
Jon.Kim: here's a map just a geographic map showing the wells that were tested back in.
Jon.Kim: This yellow area is essentially where the grassy area where the files are tested and then here in yellow the other part of this yellow Polygon or places where the trucks that were.
Jon.Kim: Transporting the firefighting farming stuff we're actually washed.
Jon.Kim: So what you see is that you see red is wells that have more than 20 parts per trillion I did say trillion so we're talking about 20 parts per trillion is the limit.
Jon.Kim: For the Vermont health advisory of five regulated compounds orange dots are wells that had abundance directional enough but less than 20 parts per trillion and green.
Jon.Kim: dots are where you had non detects there's one hi well up here, this may be associated with a plane crash that happened a couple decades ago, before this one was extended to the north.
Jon.Kim: Our approach the outcome or characterization as to general tracks i'm going to talk mostly about the physical track here, but just to let you know we do geologic mapping, which includes a.
Jon.Kim: drone surveys optical girl and surveys, we do a spatial analysis of wells GIs we do geophysics logging and although I won't talk about it much here, other than some P foss analysis, we also do.
Jon.Kim: Multiple major I trace elements stable isotopes and recharge ages for numerous wealth.
Jon.Kim: So the goals of investigation, like this we work for Vermont agency, transportation and Vermont.
Jon.Kim: Waste management and prevention division, as what we want to do is identify potential pathways for groundwater or be fast transport in the bedrock and superficial aquifers through geologic mapping.
Jon.Kim: We want to use chemical tracers to select likely P phosphor pass from phone testing sites to the wells over decades and to use that data to predict options for future P for us movement.
Jon.Kim: To give you some background on the bedrock jaws if you look up on the Left map, this is a generalized.
Jon.Kim: bedrock belt map of Vermont that's over super balls on the 2011 ratcliff at all bedrock map of Vermont just showing you that we're right down here we're at the boundary between the.
Jon.Kim: Essentially, the weekly metamorphose sedimentary rocks of the champlain valley bow and the Green mountain balances on metamorphic rocks You may know that the article I found.
Jon.Kim: This is a slip out there, we go to zoom in, and this is part of Nick reckless matt from 1999 which we use as as context, this is actually a kind of a.
Jon.Kim: postage stamp in the next button quadrangle map of them, but the salient points here are that you're looking at a CSP which is massive dollar stone you're looking at.
Jon.Kim: All as shelburne a marble and then this big sea of my new ski formation just look at the runway intersections for reference and you see that we're dealing with a large same kind of structure bonded to the West and to the East by thrust false.
Jon.Kim: We also had sufficient geologic mapping, a new one in 2008 18 done by debut some on important points here are here are the runways lots of artificial fail, which is a F.
Jon.Kim: Which is basically built on spread on places in till, there are three cross sections here just to point out, there are varying distinct differences in the thickness of these till deposits.
Jon.Kim: here's some of the GIs mass we make from from from the act relocated well domestic well coverages just to point them out and not too much detail, this is an ice pack map.
Jon.Kim: And brown sheets are where the wells of greater than 5040 feet of overburden in here static water level or potentially have netflix service map of the bedrock aquifer.
Jon.Kim: Generally, showing at this scale that Romana flow is generally following topography towards even a mill river otter creek here or towards the middle river here a bedrock surface contour map which one of your talks mentioned.
Jon.Kim: is really interesting if we put it in three dimensions and we want to consider this here's the apart, but if we shade the in three dimensions.
Jon.Kim: You know 10 what we can see is that there are knobs and little valleys in the bedrock surface, which we want to consider in terms of grammar flow and plumbing.
Jon.Kim: I want to go in through the bedrock mapping and photograph symmetry remember we're building at a really, really zone that scale on.
Jon.Kim: The structure work and stuff that Nick rapid done before, but we're down to looking at individual large outcrops at at really, really zoomed in scales using traditional campuses 35 millimeter cameras drones and we also use our gig up answer base.
Jon.Kim: So I want to give you an idea, so when you're thinking about the bed fractured better geico for what we want to know what are the possible contaminant pathways in this fractured rock act for in Vermont.
Jon.Kim: Basically, our OPS, are all the farms twice or more, and as you can see here that this is a good example of betting massive dough limited court sites here standing on end.
Jon.Kim: And then, here is another outcrop a good distance away showing in tan weathering these are dollar stones in between our carriers grey.
Jon.Kim: Flights Okay, so when you look at here, so this is clearly bedding this you're saying well it's probably betting.
Jon.Kim: But let's look at here as we start to look at what we think is betting.
Jon.Kim: We actually start to see that intro really or interest rate only between what the, whereas we think are betting are actually required ice a carnal and tight faults.
Jon.Kim: Or, and here you see another example of a doll medically are showing these is a cloud type folds you can see them here, and this whole earlier for the layering is folded over.
Jon.Kim: By an F twofold so betting is not betting it's a composite felicia to think about the next structure we're looking at asymmetric folks here at it here, and both floaters and i'll crop scale asymmetric sean's on here.
Jon.Kim: folding the dolemite and the feel like layers.
Jon.Kim: But if we start to look at after faults, we see that there's actually an F3 faults that that's folding the F two and the last one.
Jon.Kim: And so, this is a classic picture that's my finger of one of the what we have is a Dom and basin interference pattern of a ramsey Type one of you remember from.
Jon.Kim: Your favorite structure teacher that you have orthogonal full sets interfering to make dogs and basins here's a dog into a little basin basin and then you get an egg carton shape to the.
Jon.Kim: Structures here, and this view across the Middle river is an F twofold right here, and I look across the river, you see, I have three fault here, making a Dom and base.
Jon.Kim: At the larger scale.
Jon.Kim: The next event is fracture zones, we have fractures ons in multiple places we're mapping them we're seeing how far they continue whether there are continuous or whether they are an Echelon.
Jon.Kim: But just as an example here, you can see that, in short, small distance, as you can have 100 or more factors and, in many cases the fracture zones are defining the course of the river.
Jon.Kim: and the last thing they affect things is these quotations lap or fear may fit dykes than a true here i'll fractures on here.
Jon.Kim: On the right party to see that it will follow a fracture these hot magma is there actually fall betting that fall factors, maybe something to think about in terms of.
Jon.Kim: Groundwater 60 something million years later.
Jon.Kim: So I want to take you through a couple of some video, so we can start to visualize this so looking at this video and i'm going to just start in a second, this will be showing the interference or South superposition of north east, west factors all on bedding.
Jon.Kim: So this is done with photographs symmetry This is like 15 photos they're putting in with common targets, and so what you're looking at here is the here's the fractures on here is batting and we're going to spin all the way around.
Jon.Kim: So that there you're clearly seeing bedding and we're going to spin back around and there is the fracture zone.
Jon.Kim: Okay, to give you an example with things we're looking at that's a part of it all crop scale, if we look at a large outcrop, and this has got some cool music going with us look at what is clearly dorms and basins.
Jon.Kim: In this spectacular outcrops at epic kingsley mill.
Jon.Kim: outcrop now that it's probably 200 meters long.
Jon.Kim: And we're going to worry about like I said as we're thinking about what are the structures that can contribute to contaminant flow and here are at a pretty small scale, looking at the interference of F2 and F3 falls to make dorms and basis there's one set.
Jon.Kim: And there's the Ben Dom going down into a base as you spin around.
Jon.Kim: These don't invasive interference parents are.
Jon.Kim: skills.
Jon.Kim: So here is a 1010 centimeter or 20 centimeter measure, what do you see how many dogs and basins here I just in this small part of it.
Jon.Kim: point out, as we get this going here.
Jon.Kim: On the left here is one of those east, west fractures ons and the previous.
Jon.Kim: One of the first mosaic or the video I showed was from here.
Jon.Kim: Look at the factors on this is probably you know 15 meters wide and we can actually even count the individual fractures we're thinking about these these stress fractures on us being conduits.
Jon.Kim: The flashers on ends abruptly and here's what we have is we end up having batting here betting dominated zones with no fractures really at all.
Jon.Kim: let's just look quickly at how much the drainage in the area is controlled by fracture sets the middle rubber is very straight it takes a bandwidth one fracture set back with another set and here is a lamp or fear date falling following a fracture zone.
Jon.Kim: We did you visit a logging we used one oh comma we use temperature and conductivity gamma caliper i'm just going to concentrate on acoustic tell you later to put together with the other data so basically look at the red thumb tacks we log wells 1234567.
Jon.Kim: I put all the data together on this this great fracture map, so any place where we have field data i've got data.
Jon.Kim: On the Rose diagrams on the Left equal area and that's on the right fractures in black betting is in red.
Jon.Kim: On the wealth that we loved we done differentiated structure, so we have them actually in Turquoise pedals, and so what correlating the factors we see in the field with those we're seeing the borehole.
Jon.Kim: Along guards road which is basically just south of the airport, this is what the Cross section looks like by putting together lots of this data it's basically a box for the alkaline going into a sync client and backup towards our client.
Jon.Kim: i'm just going to throw in one bit about the ethos data Okay, here it is let's just look at the different laws you've seen this slide before is read in between is orange.
Jon.Kim: Note attacks are in green if we break it into the different people's compounds look at these two l's here orange our flow tellers these are newer P us compounds that are used in more recent farms.
Jon.Kim: And you see them they're only here as we get to the West, we get PR PR E PA re s and E, F.
Jon.Kim: H access which is six carbons so we can look at the p for signature in different parts of the field area to give an idea of how.
Jon.Kim: Old an offer the price has been transported and what i'm going to wrap up here, where this is a cool 3D video for the model that shows.
Jon.Kim: Here the bread hexagon is the is the area where the phone is test over years here's the runways.
Jon.Kim: In barn on the walls that we did geophysical logging on and it purple are the structural demands, where we measured lots and lots of fractures and bedding so watch what happens, what if we run this video putting the.
Jon.Kim: clients in client bear now the blue planes are betting.
Jon.Kim: The red ones are fractures and so you see that the actual surface of this anaconda sin compare is bet out, which is enough to fall by the F3 floats.
Jon.Kim: And what we're looking at here a fracture zones to the southwest part and and this that we are able to map out another one up here, and so what we're thinking about is if this is the source area for the P, for us, the sin climb would provide natural.
Jon.Kim: Essentially downgrading diversion into the same client trough it can flow down this way towards the Nile river there's gotta be some breaches in the fold actual surface.
Jon.Kim: Probably by these east, west fracture zones and when you when we get on the other side, we need to think about the east, west for actors on.
Jon.Kim: And the other side, the other limb of this an incline in terms of surfaces to worry about for be fast, transport and that's a wrap up i'm just showing you what our goals were and i'll and there.
Nick Hastings: Thanks john boy that's you know there's a couple of comments that I would certainly echo in the chat regarding you know, especially in this coven university the virtual field trip component of what you're showing there is is huge from a learning experience.
Nick Hastings: I don't know if either the folks who threw something in the chat want to chime in themselves, or if there are other questions that folks have.
Nicole Insolia: I was gonna say those really interesting ways of how you were able to turn.
Nicole Insolia: Those images and provide a perspective that normally you can't just see looking at an outcrop if you're standing at it.
Nicole Insolia: would have been extremely helpful when I was taking structure, because it's so hard to visualize those those dimensions, when you can't always look at it in that way, but you were able to manipulate it and turn it and I thought that was really thought provoking.
Jon.Kim: yeah, let me just say one thing that we've learned from doing these contaminant studies, is that you have to look at all structures at all scales.
Jon.Kim: And by using our hands and knees measuring by using a 35 millimeter camera and then going up to drones john scales and then integrating them, it really gives us an idea of what are the possibilities for P fast transport.
Nick Hastings: And the multiple multiple facets of the decimation in the preferential pathways changing at all those scales is incredibly useful to look at in 3D 40, for that matter, as as people are pointing out mean we find ourselves in the environmental sector.
Nick Hastings: Having to describe fate and transport of contaminants with complex pathologies all the time and we use we use 3D and in time sequence 40 graphics of that nature.
Nick Hastings: But it's not often in a in a case where you have you know 123 sets of cross cutting features like that which so kudos that was very informative.
Jon.Kim: Well, no, just one one point is that I didn't present it because I would have to take much more time, but anyway, we do have groundwater recharging states, and we have.
Jon.Kim: big differences we have water that's coming that recharge die and the Green mountains that has made its way down to the airport plateau and that's over 70 years old yeah.
Nick Hastings: amazing great stuff any other questions or comments.
Nick Hastings: Not we will keep on on target here thanks again john and Mike you can introduce the next.
Mike Apfelbaum: Alright, so our next speaker is Zack Smith from what are the current and he'll be presenting integrating multiple site investigations, but multiple site investigation methods to characterize groundwater, surface water impacts and develop an optimized remediation strategy.
Mike Apfelbaum: let's go ahead jack.
zsmith: I just want to confirm that you can see my screen and that you're seeing the correct view.
zsmith: weekend okay great so thanks everyone um this has been really, really interesting i've really enjoyed a lot of these presentations on really awesome stuff and actually.
zsmith: There are some similarities between the the talk that i'll be giving and one we just saw although we're at a much, much smaller scale than the last one.
zsmith: So i'm going to be looking at integrating multiple site investigation methods to characterize groundwater, surface water impacts and really the focus of this is on optimizing a remediation strategy so it's going to be a little bit of a different twist than the talks we've seen so far.
zsmith: So, my name is zachary Smith i'm a project manager with water to encourage and I also want to acknowledge my co author here Greg Reynolds, who is a project scientist and has really done a lot of fantastic work both at this site and also on this presentation.
zsmith: will start by reviewing the objectives and then providing a project introduction then i'll review how we went through and developed a conceptual site model over time for this particular release area and then really the bulk of the work is going to focus on.
zsmith: Presenting that CSM within a remediation optimization framework and also highlighting some of the tools that we used to optimize remediation and you can see those listed here i'll wrap up with just highlighting what the next steps for the project is and then talk about conclusions.
zsmith: Alright, so the objectives if if I do my job correctly i'll hopefully demonstrate that a CSM can involve can evolve through time sometimes leading to identification of new issues but importantly also new solutions.
zsmith: How further developing a more detailed CSM as part of.
zsmith: A remediation process allows for more effective.
zsmith: remediation of reduce costs, improve sustainability obviously all of the goals that we try to achieve, and also how complex projects often require multiple integrated technology is for both assessment and remediation.
zsmith: Okay, so I think I might be the first person in this session that's going to have to do this somewhat annoying thing, where I cannot tell you exactly where the project is.
zsmith: But I can tell you that it's a large industrial facility and that work has been going on at this project site for honestly, for decades, and most of that work has followed.
zsmith: assessment and remediation of the areas of concern, this is kind of you know, the bread and butter for the environmental consulting types on.
zsmith: This presentation focuses on a metals impacted area that shown in the red box here, this is a small subset of the project site overall.
zsmith: So what happened here well really what happened is that elevated metals primarily cadmium copper and zinc were identified in a well adjacent to a river now this well was installed really not to assess this particular area, but it was installed.
zsmith: To provide overall groundwater monitoring data really for the facility at large.
zsmith: and
zsmith: Once the metals were identified and groundwater subsequent sampling of the surface water in the River located just adjacent to this well identified those same metals so.
zsmith: We knew that there was some sort of mechanism basically a pathway leading from impacted groundwater discharging into surface water and causing metals, to show up and surface water above background.
zsmith: So the early steps that were taken, this is probably not a surprise to anyone included, of course, installing a second well to confirm that you know this was a real issue, and that was confirmed.
zsmith: Then there were steps taken to review historical documentation for the area so looking for you know if there was some unknown historical feature located.
zsmith: In that area, if there were utilities, who were a process piping, or if there was any documentation of buried waste or degraded film material anything like that.
zsmith: And documentation really didn't turn anything up so with no clear release mechanism, a test pit was excavated to inspect the subsurface for evidence of release.
zsmith: And further phases of traditional environmental side assessment were completed using tools like soil borings and monitoring wells and sampling really to confirm both the degree and extent of impacted soil and groundwater.
zsmith: And should just highlight real quickly the work did ultimately confirm that it was impacted film material containing very high concentrations of metals, that was the release mechanism for this area.
zsmith: OK, so now that we know what the problem is, we turn our focus to solutions, so you can see here that concentrations in groundwater are really very high for.
zsmith: Especially zinc copper and cadmium and they are causing concentrations in surface water to also be elevated and.
zsmith: Of note the surface water concentrations do exceed certain aquatic life cleanup goals so there's a need here to take action to reduce concentrations discharging into the surface water, because there is a an aquatic risk associated with that and, of course, the work.
zsmith: In the past, involved things like shallow and deep wells and traditional site assessment techniques and that information is helpful, it allows us to identify.
zsmith: You know whether this is a shallow only issue or deeper issue, it helps to inform remediation decisions.
zsmith: And ultimately, when we performed all of this work, we identified a rather large area containing this degraded film material and.
zsmith: then start to think about what to do about it and, as you can imagine excavating 60,000 cubic yards of impacted film material and transporting it off site is incredibly cost prohibitive.
zsmith: And also unnecessary to achieve, protection of the environment, and I would also note it's you know not within the tenants of green and sustainable remediation That would be a very.
zsmith: Carbon intensive action to perform all of that excavation and transportation.
zsmith: So next we need to understand a little bit about a remediation optimization framework and there's, there are aspects to this that we think about all the time, but that might be a little bit counterintuitive to people so.
zsmith: it's widely known that inadequately detailed conceptual site model contributes to contributes to incomplete or delayed remediation and inflated overall remediation costs.
zsmith: What that means, which is the counterintuitive part is that spending a little more money on improving the detail of your conceptual site model actually can result in an immediate return on investment and ultimately result in quicker, more effective cleanup reduce costs and improve sustainability.
zsmith: Now we take an integrated approach to improve a conceptual site model as part of what we call remediation optimization, and this is really a.
zsmith: Essentially, a bundle of services that we tried to apply for remediation optimization purposes those.
zsmith: Steps include what's called high resolution site characterization or HR sc geological contaminant modeling sometimes also called environmental data visualization.
zsmith: and groundwater modeling and all three of these approaches work together to provide significantly more detail in your conceptual site model to improve the efficacy of remediation and to reduce costs and improve sustainability.
zsmith: So we'll focus first on high resolution site characterization.
zsmith: So what is high resolution site characterization it's often the most effective tool to characterize complex site hydro geology EPA defines it and i'll just real quickly read this.
zsmith: The set of strategies and techniques that you scale appropriate measurements and sample density to define contaminant distributions and the physical context in which they reside with greater certainty supporting faster and more effective cycling.
zsmith: So that's a mouthful, but in practice at usc is really a site characterization paradigm that aims to collect sufficient data to understand site complexity.
zsmith: And what I mean by a paradigm is that it typically incorporates looking at lingering data gaps systematically.
zsmith: Considering mass flux based evaluations, in addition to simply contaminant based evaluations evaluating flow versus storage zones and your subsurface and taking steps to better understand formation permeability.
zsmith: Also high resolution site characterization typically involves using some of the more advanced site assessment tools that have been on the market now for a while, this includes things like.
zsmith: The Waterloo profiler and other direct push probes that can be inserted into the ground and us to develop these detailed profiles of either concentrations or hydraulic conductivity things like that.
zsmith: So HR sc was performed within the metals impacted area, this was a metals area, so we could not use, you know some of the direct sense and tools, but what we did is we installed a high resolution grid of soil and groundwater.
zsmith: borings and collected data really from the ground surface into the water tables, so this results in really a very high resolution grid of data in three dimensions.
zsmith: We evaluated concentrations of metals soil pH groundwater pH formation permeability and for metals, the testing included both totals and leeching potential.
zsmith: concurrent collection of geotechnical data readability testing data, and of course we incorporated historical data and performance and mass flux evaluation.
zsmith: Next we'll look at the data visualization part.
zsmith: So, once we have these grids of soil and groundwater data we distribute them in three dimensional space using creaking to build a model of the subsurface and really it's very.
zsmith: Key to understand that this model itself is such a powerful investigatory tool.
zsmith: It allows for characterizing beyond simple intuitions you can really look at your data spin it around look at different shells and get a much, much greater understanding of what's going on.
zsmith: And of course it also allows you to do quantitative analyses that can be integrated into other other types of work.
zsmith: um it's not really possible to show you the three dimensional models, although I could have done the cool animations like we just saw.
zsmith: But what we've done is taken some slices through it and here they're going to be presented in trance X essentially parallel to the to the River a closest to the river and see farthest away.
zsmith: And what you can see is that there is a distinct heterogeneous distribution of metals within this film material.
zsmith: But also very interestingly there's a pH pattern that's going to show up here, you can see the metals, this is a plan view of groundwater that i'm showing you, you can see that the concentrations and groundwater match what we just saw on soil.
zsmith: pH, however, has a really an isolated area of very low pH which has implications for remediation.
zsmith: Here you can see pH and groundwater and it matches very closely as well, so we have multiple lines of evidence that what we're looking at is is good data.
Nick Hastings: And that's it.
zsmith: yep got it groundwater modeling is the next step.
zsmith: So, as I mentioned.
zsmith: Really, in order to do this work best we want to achieve reduction in the flux into the stream and we use the six layer three dimensional numerical groundwater flow model to to estimate the flux into the stream and to develop site specific cleanup goals for groundwater.
zsmith: Here you can see that.
zsmith: Through this exercise we essentially looked at what concentrations, we needed to get to meet aquatic toxicity goals, given the flux of impact of groundwater during low flow stream conditions and develop those very specifically.
zsmith: We then determine that in situ treatment and stabilization was the favorable approach and we performed a treat ability study.
zsmith: Here we're really looking at altering the conditions of the subsurface in order to form a stable precipitates that will immobilize the metals.
zsmith: And we tested, a number of amendments to do that, as you can see here, this is a large quantity of data.
zsmith: Of course, the testing included both the vedas and saturated zone included controls Monday multiple amendments and mixtures different concentrations.
zsmith: And it was really performed in two phases, where we looked at an initial phase to identify likely candidates to be able to to provide the stabilization.
zsmith: And then a second phase, in order to refine the dosing and also to incorporate some geotechnical testing to see what effects on unconfined impressive strength and hydraulic conductivity we would have with our amendments.
zsmith: Alright, so let's quickly review the remediation area we started with this large area of degraded film material.
zsmith: We develop the high resolution understanding of concentrations leaching potential and hydro and geotechnical parameters.
zsmith: We developed site specific cleanup objectives based on groundwater discharge into surface water during low flow conditions, and then we performed extensive testing of amendments and doses that would allow us to stabilize metals and soil.
zsmith: So we used all of that to develop an optimized for mediation approach and, as you can see here this really involves.
zsmith: Essentially surgically injecting various amendments into various portions of our three dimensional understanding of the site in order to stabilize metals and soil and reduce the flux of metals into groundwater, this is a depiction of the design that we came up with.
zsmith: And we're currently in the process of finalizing that design or going through permitting in the spring of this year will install additional wells, including the.
zsmith: Transit the transact of down gradient wells for compliance monitoring and mass blocks evaluation, the first phases, the pilot scale implementation are scheduled to occur in the spring and summer of this year, expanded, this is needed in 2022 and achieve hopefully compliance in 2023.
zsmith: And conclusions, hopefully um i've a chief the objectives that I set out to I know i'm running short on time here.
zsmith: But I think you know, a CSM can evolve through time lead to identification of new issues and solutions, a more detailed CSM really can allow you to have more effective remediation reduce costs and improve sustainability and complex projects often require multiple integrated technologies.
zsmith: I do want to acknowledge real quickly the numerous woodard and turn staff that contributed to really excellent work on this project through the years.
zsmith: The laboratory work for that treat ability study that I showed you was provided by proxy Captain now ivanek and we had support from client representatives regulators and other stakeholders for this project, so I want to acknowledge that as well.
zsmith: questions.
Mike Apfelbaum: Thanks zach it looks like we got time for maybe one quick question, then, but he's.
wants to weigh in.
Mike Apfelbaum: I had one question with regard to differentiation of the individual remedial amendments that were selected for each of the areas and looks like it came up with a lot of different.
Mike Apfelbaum: combinations there, here we speak to how that was what you know how you would treat the results for the readability work translated to you know that that break down to those different amendments of those different phases.
zsmith: So you mean how we determine which amendments to us.
Mike Apfelbaum: Yes, within which each area looks like there was a lot of decisions that went into that.
zsmith: Oh right yeah it so there were a lot of decisions they really had to do with looking at both the concentrations and also, particularly the pH.
zsmith: That soil pH I didn't have time to go into it, but that really presents a lot of challenges for using an institute chemical reduction technology to stabilize metals and there was this portion of the phil that had just very, very low pH and was difficult to treat so.
zsmith: there needed to be some special consideration in order to accommodate.
Mike Apfelbaum: Great.
Mike Apfelbaum: Well, Nick I will turn it over to you to introduce.
Mike Apfelbaum: The final speaker so we can keep on schedule here.
one.
Nick Hastings: hey thanks zach and.
Nick Hastings: or last platform speaker before we move on to posters is Janet Barclay from the usgs right here in sunny Connecticut.
Nick Hastings: And she'll be presenting simulating groundwater flow and nitrogen transport in coastal watersheds on the North shore of long island sound which if I look around my window right there, I can see.
Janet Barclay: I can get a nice view out your window.
Nick Hastings: I live in Madison just so you can put it on the map very.
Janet Barclay: Nice Nice.
Janet Barclay: So yeah my name is Janet Barclay and I am hydrologists with the US geological survey in the New England water science.
Janet Barclay: Center and i'm going to be presenting some work but john millennia, and I have been doing on simulating groundwater flow and nitrogen transport on the North shore of long island sound.
Janet Barclay: Long island sound is a coastal estuary that's located between long island New York and Connecticut.
Janet Barclay: And, as with many coastal estuaries elevated nitrogen has been a pervasive issue in the sound and it's been the focus of extensive management activities really over decades, some of the ecological effects of elevated nitrogen include fish kills algal blooms and frequent hypoxia.
Janet Barclay: The nitrogen in long island sound comes from a number of different pathways and is transported or number of different sources and it's transported along multiple pathways both surface pathways and subsurface pathways.
Janet Barclay: And compared to the surface pathways the groundwater pathways are relatively understudied.
Janet Barclay: But although there understudied the available data suggests that groundwater transport of nitrogen in this area is important.
Janet Barclay: In the Naga took river, where the nitrogen inputs are dominated by point sources which discharged directly to river the River bypassing the groundwater total nitrogen loads decreased from 1995 to 2016.
Janet Barclay: In contrast, in the norwalk river, where the nitrogen inputs are dominated by non point sources so once that typically travel through the shallow groundwater, we see an increase in total nitrogen loads.
Janet Barclay: during that same period in Connecticut median nitrogen concentrations in better than groundwater were much higher than measured in surface water again suggesting that groundwater may be an important pathway for nitrogen transport.
Janet Barclay: But despite this managers often lack tools for understanding the role of groundwater and transporting nitrogen.
Janet Barclay: And so, this project was attempting to address that gap through a collaboration between the US geological survey the Connecticut department of energy and environmental protection and the US EPA is long island sound study.
Janet Barclay: The objective of the project was to provide actionable information about groundwater flow and nitrogen transport on the North shore of long island sound.
Janet Barclay: To do that, within a two year project timeframe and to do it in a way that informs future studies in the area.
Janet Barclay: we've wrapped up the first phase of that project and we received funding for a second two year phase where we're eternally refining the work from the first phase, based on what we learned.
Janet Barclay: The city area for the project extends from narragansett Bay there on the east boundary to the east river in New York City on the southwest the southern boundary is one kilometer off the coasts into long island sound and the northern boundary is set at watershed divides.
Janet Barclay: In total, the study area covers just over 9000 square kilometers.
Janet Barclay: Our basic approach has been to use the traditional groundwater tool MOD flow groundwater model, coupled with post processing using MOD path.
Janet Barclay: But to develop it internally and using automated scripting tools and this allowed us to get the model developed quickly and then to refine it as needed.
Janet Barclay: And so we started with a simple steady state groundwater model, the spatial resolution was course about 300 meters.
Janet Barclay: The inputs came from national data sets and the geology was simplified into three groups of course settlements find settlements and bedrock.
Janet Barclay: We created the model, using a series of Jupiter notebooks that allowed us to get the model up and running, within a matter of days, and then to identify the areas where we needed to focus our refinement efforts.
Janet Barclay: Because coastal Connecticut is densely populated and has extensive areas with private wells and septic system, one area where we needed to do some refining work was the water use data.
Janet Barclay: And so, in Connecticut detailed information regarding water withdrawals, in particular for water supply wells and private wealth is not readily available.
Janet Barclay: Annual withdrawal rates from had previously been compiled for larger water supply wells, and then we had to estimate the withdrawal rates and the locations for the remaining water supply wells using a combination of service area maps population served and some per capita use estimates.
Janet Barclay: We then estimated the both the locations and the withdrawal rates for domestic wells using water supply service area maps population density and estimated use rates and the assumption that wells were only used in areas without public water supply.
Janet Barclay: Because one of the motivations for this work is to simulate nitrogen loading we needed to estimate septic return flows, and so we did this, similarly to estimating the domestic well withdrawals using and except that we use to your service maps.
Janet Barclay: After developing the initial model we used a second set of Python scripts to prepare the model for calibration using past plus plus which is common model calibration software.
Janet Barclay: And so, in preparation for that we adjusted the recharge estimates using base flow at gauges within the study area that had minimal effects from withdrawals, and then we also refined the geology.
Janet Barclay: and increasing the number of classes of unconsolidated settlements and the number of classes of bedrock that are represented.
Janet Barclay: Those Python scripts that we were using automatically retrieved the mean water levels from wells and mean baseload from the gauges that fit our.
Janet Barclay: Inclusion criteria and then generated the input files for past, and so, because the model creation and the calibration preparation we're all done with scripts we can easily adjust our conceptualization of ground water in this area and then.
Janet Barclay: We run the scripts and get a new calibrated version, the model relatively quickly.
Janet Barclay: Representative observations for model calibration when we're looking at this regional kind of skill can be somewhat limited this figure shows the well.
Janet Barclay: that are available to us as black circles and the stream gauges as black triangles with their associated watersheds in grey that we had available to us for water for calibration.
Janet Barclay: And although these observations are relatively well distributed spatially across the study area there's many gaps that exist between that.
Janet Barclay: And so to address this, we used a modification of a metric developed by Star and bell it's based on the observation that in humid areas like our study say the water table is typically above the bottom of perennial streams and below the land surface and other areas.
Janet Barclay: And although this metric only gives us one directional errors, where the water table is too high and terrestrial cells are too low and river cells.
Janet Barclay: It does provide a measure of model performance in every cell and this greatly enhances the spatial coverage of the calibration data.
Janet Barclay: And so, this figure shows the locations of those observations with red indicating areas where we expect the water table to be below the land surface and blue indicating areas where we expect it to be above the bottom of a stream or river.
Janet Barclay: What important consideration in any modeling project is the resolution higher resolution models may produce more precise predictions.
Janet Barclay: But they will most certainly required greater computational resources and longer run times.
Janet Barclay: And our initial model we use the course spatial resolution to keep the runtime relatively short.
Janet Barclay: This was particularly important for the calibration when we were running the model many times and so with the course resolution I could run that calibration in parallel on my laptop started at the end of the day, and it would be done when I started work, the next morning.
Janet Barclay: But the spatial resolution also affects the model predictions, particularly the mapping of areas of groundwater discharge an estimation of the groundwater troubled times.
Janet Barclay: So, to understand the effects of grid resolution on our model predictions we developed three inset models of differing special resolutions for one sub watershed within the study area.
Janet Barclay: These maps show simulated areas of groundwater discharge for a 300 meter hundred and 50 meter and 75 meter resolution models.
Janet Barclay: you'll see that the general pattern of discharge is the same, but because the grid cells are larger with the coarser model, a greater fraction of the model area has groundwater discharge.
Janet Barclay: And this has substantial implications for calculated groundwater troubled times, which are based on tracking hypothetical particles of water, through the subsurface when those particles start in areas of groundwater discharge they discharge immediately with a travel time of zero.
Janet Barclay: And so we're looking here at the cumulative distribution of travel times for the three models, with different resolution, and if we zoom in on these shorter travel times here.
Janet Barclay: Here we start to see that those patterns in the area extent to brand were to discharge reflect in the percent of particles that discharge it with the travel time of zero.
Janet Barclay: And in the media and travel times and so to balance the retired required computational resources and the model predictions for the broader study.
Janet Barclay: We chose to calibrate the course or 300 meter model and then apply those calibrated parameters to the 150 meter model to use for our predictions.
Janet Barclay: And so, too, we wanted to compare the fit for those two and so here we're looking at the simulated well water levels on the y axis and the observed well water levels on the X axis.
Janet Barclay: We have the calibrated course model on the left is the 300 meter model and the final resolution hundred and 50 meter model on the right.
Janet Barclay: And you can see that those two models have nearly identical fit the observed data and so going forward we are confident that we could calibrate the course model and then use those calibrated parameters in the final resolution model for the predictions.
Janet Barclay: Once we had an initial groundwater flow model we're able to do a demonstration analysis of nitrogen transport within one sub basin.
Janet Barclay: The focus area for this was the niantic river watershed which is located towards the eastern and of Connecticut.
Janet Barclay: within an attic river estuary nitrogen levels are elevated but eel grass beds are present, and so this combination suggests that this estuary could respond well to nitrogen management.
Janet Barclay: In addition, some prior work in the watershed measured based flow nitrogen loads at a number of places throughout the watershed which we were able to use for evaluation of the model.
Janet Barclay: So the nitrogen model simulates effective transport of nitrogen you and we do that, using broad path so we estimated the nitrogen inputs using land cover.
Janet Barclay: Based on work by Jamie badri at all, and then we calculated the final nitrogen load using those inputs and zone based attenuation factors, also from badri at all the groundwater flow model connects the input location to the discharge location and provides the travel times.
Janet Barclay: And so, using the groundwater flow and nitrogen transport models we've been able to provide actionable information within.
Janet Barclay: The two year project time frame, some of the some of the outputs we've provided include things like mean groundwater travel times aggregated at the puc 12 watershed level.
Janet Barclay: The importance of septic return flows again at the at that watershed level.
Janet Barclay: The relative importance of groundwater discharge to coastal waters versus inland waters, and this is really important, because.
Janet Barclay: When we start to think about nitrogen transport because nitrogen that's discharging to England waters has the potential to be removed through industrial processes like biological uptake and D notification prior to reaching those more sensitive coastal waters.
Janet Barclay: As well as being able to provide maps of nitrogen input by travel time and this kind of information can guard guide management initiatives, for example, highlighting areas that have greater septic density and longer groundwater troubled times.
Janet Barclay: As we're entering the phase two of this project we're actually using the things we've learned during the first phase to inform how we focus in on the second phase, and where that's true for both the groundwater model and the nitrogen model.
Janet Barclay: One thing that we learned from the model is that the groundwater travel times in this region are relatively short.
Janet Barclay: The model wide median is just under two years and about 38% of the groundwater is stimulated to discharge within one year.
Janet Barclay: For comparison on long island just across the sound to the south, so extensive modeling studies have shown that the most groundwater discharges within five to 10 years.
Janet Barclay: More than 25% is from aquifers with troubled times of more than 150 years these relatively short troubled times suggest that decades long nitrogen legacies are not widespread here, which is in contrast to some of what we see down in the Chesapeake bay and in the Mississippi watershed.
Janet Barclay: But also seasonal transport dynamics might be important, and so one of the things we're looking into in the next iteration is whether we need to stimulate seasonal flow and transport.
Janet Barclay: The approach to this project has been to start simple and add complexity as needed.
Janet Barclay: In phase one the representation of groundwater, surface water exchange was relatively simple groundwater could discharge from the aquifer to the river.
Janet Barclay: But not flow in the reverse direction and at a regional scale, this is a in the northeastern us this is a relatively reasonable.
Janet Barclay: assumption, but it does obscure more complex exchange processes, and so what we're looking at here is a map of groundwater discharge two streams across the model domain with darker blue indicating greater discharge the black areas indicate areas of no exchange.
Janet Barclay: Preliminary results with a more complex models suggest that some of those no exchange areas.
Janet Barclay: Maybe areas of losing reaches where water flows from the stream into the aquifer those are shown in shades of red and so again in phase two will be working to implement those more complex exchange processes.
Janet Barclay: will also going to be working to reduce the grid resolution as much as this computationally feasible for the reasons I mentioned earlier.
Janet Barclay: Nitrogen loading and attenuation are complex and spatially heterogeneous, and so we began with a simple demonstration bottle and a limited spatial scope in Phase one.
Janet Barclay: And phase two will be revising the input and loading factors and attenuation factors based on more extensive review of literature and existing data.
Janet Barclay: will also be extending the nitrogen bottle from just the niantic watershed to throughout the to the entire groundwater model domain.
Janet Barclay: And then finally we'll be stimulating the effects of different nitrogen management scenarios, to see what might be some of the best options for mitigating broadwater nitrogen.
Janet Barclay: And so, in conclusion, by developing this model in collaboration with our management partners using scripts and an iterative approach and especially distributed performance metric.
Janet Barclay: has allowed us to quickly generate the initial model results and then to strategically target the refinement efforts as we start this next phase so with that, like to thank you for joining in and i'd be happy to answer any questions.
Nick Hastings: Thank you Janet excuse me it's very cool i'm I want to open the floor up for questions, but I have some to.
Nick Hastings: not seen anything in the chat as of yet, but I will open this up to see if folks are raising their hand, so the the mapping that you showed the mosaic of different mapping.
Nick Hastings: interested in what the intended audience or who you are.
Nick Hastings: Helping with those management decisions around say septic the concurrence of.
Nick Hastings: Small residents time of groundwater and larger density of septic is that a local management or is the state have some sort of.
Nick Hastings: ability to try to you know regulate that or who you're working with.
Janet Barclay: So we've been doing it.
Janet Barclay: yeah so we've been doing that project and collaboration with the Connecticut department of energy and environmental protection, so the state our.
Janet Barclay: State Agency here in Connecticut and they have some role in regulation.
Janet Barclay: And in you know, encouraging different initiatives and studies and things and so so yeah so they've been our primary client and audience for that that work.
Janet Barclay: it's also been done in collaboration with the long island sound study and so they're thinking a little bit more holistically about nitrogen inputs into the sound and different post focuses there.
Nick Hastings: Because I know that some of the certainly the boots on ground septic management is is a local thing, but if the dp is.
Nick Hastings: Providing rules and regulations and guidance there to, then you know, the net change.
Janet Barclay: yeah yeah pervasive.
Nick Hastings: So got some questions in the chatroom Peters asking how you did you date the groundwater.
Janet Barclay: We did not we that's that's one difficulty with these regional scale studies, is that you know we have.
Janet Barclay: Groundwater age dating and a couple places but it's difficult to it's it's not very spatially expensive and it's difficult to kind of take a couple individual points and make sense of How does that what does that mean when you're looking at a regional scale study.
Nick Hastings: And Eric ads could you explain why the model groundwater travel times are so short.
Nick Hastings: And the long island sound, and I assume he meant the Connecticut side and perhaps just for everyone's benefit because I know that it's a very different type of aquifer across the sound, by contrast, why it's so much longer in long island.
Janet Barclay: yeah so I mean that that a lot of it comes down to the the geology you know, on on long island there's meters in years of course settlements and so versus on the the Connecticut side.
Janet Barclay: You know, we have much thinner overburden a lot of glacial till you're ready, we have areas of course or settlements, but.
Janet Barclay: You know the drainage network is the surface water drainage network as much denser on the North side so yeah it just comes down to pretty different geologic setting yeah.
Nick Hastings: Great.
Nick Hastings: Then you've got some thanks for Nice integration of approaches from from Peter um any other folks one asked questions, if not, we will thank Janet and.
Nick Hastings: Everybody can cross their fingers because we're going to do the posters next, which means that hopefully I click the right buttons in the right order.
Nick Hastings: Thanks Janet.
Nick Hastings: And I will start pulling that up and maybe Mike you can.
Mike Apfelbaum: I can do, the first one i'm ready to go with that one yep.
Nick Hastings: You want me to display it.
Mike Apfelbaum: I already have it up.
Nick Hastings: support, then let me.
Nick Hastings: We can switch and you can show them all, because once you're sharing your screen it's just a question of clicking the links, as you go.
Mike Apfelbaum: Everybody you see that.
Nick Hastings: not yet you have to share the screen.
Mike Apfelbaum: There we go it's coming.
Nick Hastings: There you go and you have the video.
Mike Apfelbaum: I have the video ready to go.
Mike Apfelbaum: Okay, all right here we go.
Mike Apfelbaum: i'll just read the title real quick just anybody can see it.
Mike Apfelbaum: In it's a presentation by our poster presentation by Jacob wacker and it is ground penetrating radar instead of into logical analysis of an anthropogenic Lee very disturbing bed South central Pennsylvania.
Mike Apfelbaum: implications for ground water flow paths any spring fed plane in Jacob is from shippensburg university, so our planet.
original goal of our study was to identify.
Nick Hastings: Share sound.
Nick Hastings: let's give it a shot.
Nick Hastings: Hello everyone the original goal of our study was to identify and confirm the location of the buried stream channel.
Mike Apfelbaum: And that's one point and we did this by using ground penetrating radar and comparative settlement hall logic analyses This project was done for a Scientology class during the fall 2020 semester.
So we had to research questions one was where's the location of the berry stream channel of old bird run and to Kendall location of the buried stream be confirmed through sentiments illogical analyses of the stream bed sediments from both the old and restored stretches of stream.
Mike Apfelbaum: The study area focused on the restored and buried stretches of bird run and the township park east of shippensburg University, which is situated in Cumberland county South central Pennsylvania.
Mike Apfelbaum: Methods consisted of four phases phase one we collected and characterize stream channel sediments from the restore channel.
Mike Apfelbaum: And phase two, we ran mala X three mg PR at 250 megahertz across several translates over potential buried channel locations.
Mike Apfelbaum: During phase three we located and Doug test pits in order to recover subsurface sediments to compare with known string deposits and during Phase four we said analyzed and compared sentiment grain size distributions to confirm buried channel location.
OK so moving on to the results section, we were able to produce a size frequency curve for three to seven samples collected.
And so here, you can see the similarities in each of the curves we have a little bit low of a peek here at the file sizes negative two for the old bird run sandpoint a little.
peek here at file size of one for the old bargain sample, and so this piece here may be attributed to the settling of the final assignments when the old channels back, though.
So besides the similarities, that the curves another strong correlation between the samples was the similarities of their composition, as you can see here, these are composed of mostly sand stones and limestone.
And their degree of sorting evidenced by the frequency curve here was also very similar as well, along with their their grounding characteristics so moving down to the gdpr transact.
We were able to identify three distinct stream channels.
To have which became a particular focus the middle channel here.
Is picture down below and is where we also recovered the segments for the old bird run sample up here for comparison between these samples.
And so it's important to know that there is actually groundwater still flowing through the stream channel which may be attributed to a variety of reasons.
This third stream channel over here on the right.
We handle longer down within that area and we're also able to recover some sandy public segments also characteristic of the.
stream channel on the left hand side so for this investigation were able to successfully compare the stream segments, to those of the very truth shall segments.
That showed a strong unit total correlation of sandy find ground with a mode Center that negative two five.
And so the similarities can likely be attributed to similarities in flow velocity which is likely, the case of nearly identical varying size characteristics.
So current velocities window, the way the finer segments, such as Celts and plays and so visual comparison of these green assemblages show similar degrees of rounding sorting in composition.
Now the presence of flowing groundwater nodes within the excavated channel.
Even after burial can show that there is a another source of groundwater located somewhere within the floodplain or it's likely to be coming from the still flowing stream itself that opens up the door for.
Future investigation within this area.
So thank you for listening to these presentation, I hope you enjoyed it.
Nick Hastings: Alright, so I believe.
Nick Hastings: Jacob, you might be on the line, so people have questions I actually probably should put it back up that's kind of a good thing to have up if you're going to have questions, so let me re share my screen the meantime folks folks want to pose questions or put them in the chat.
get it back up.
Nick Hastings: Chris now I don't have my other screen up so.
Nick Hastings: Mike if you want to run any q&a.
Mike Apfelbaum: Well, I can't I guess my audios I have on my desktop that's why I was running them and that's what I think my challenge was.
Mike Apfelbaum: For some reason you're going through the GSA contracts.
Mike Apfelbaum: I can't get into that.
Nick Hastings: I see yeah that's that seems to be the smoothest.
Nick Hastings: The other thing they just for future reference.
Nick Hastings: You have to share the sound when you share the screen there's a button, but the button.
Nick Hastings: When you hit share screen before you share your screen you hit the share sound.
Nick Hastings: Alright, are there are there are no questions, in which case we'll move on to the next one.
Mike Apfelbaum: There was one question there at the end there, Nick I don't want to pause for a second.
But.
Mike Apfelbaum: It was regarding how steep was the area we're working on.
Mike Apfelbaum: General.
Jacob Wacker: Okay yeah I can answer that question.
Jacob Wacker: So we're actually working down in the valley between two mountains, so an area that we were working it was more or less in a floodplain so it was relatively flat.
Jacob Wacker: And alive those sand stones likely came.
Jacob Wacker: From the mountains themselves as they were whether the way.
Mike Apfelbaum: Okay, great.
Nick Hastings: All right, I can move over to the other poster.
Nick Hastings: And i'm sorry I should.
Nick Hastings: introduce the next a poster is by brandon day from susquehanna university and it's on aquifer heterogeneity by means of er T and boring logs a case study in sere school Hannah university.
Nick Hastings: guess study and cirie.
Okay.
hello, my name is brandon day i'm a senior earth and environmental sciences major a Cisco handy university for this project, I worked alongside Dr all men, the show.
And our goal, this project was to identify aqua for huddle geniality and underground flow patterns by the means of the RT inborn lungs.
Are study took place at this year so school, university this year is the Center for environmental education and research.
On the specific site that we worked on that this year was an old form pasture field where we had a stream bed on the North and West side of us and the railroad bed on the South side of us.
Nick Hastings: For our experiment to measure the receptivity we use the superstition are a resistive any meter we use a dipole dipole right that we downloaded into the superseding the using the agi admin software that out in the field we use 56 electrodes that were spaced half a meter or.
Once we had everything set up, we did our 11 year to surveys, with the dipole dipole rei each survey was two meters apart.
And then, once we had all our party surveys completed going back to the lab and we use the earth imager 2d and 3D software to analyze our data.
But the 2d we get our 11 single profiles to see on the right side of the poster and then with the 3D we combined all the 2d RT.
rizzotti profiles into a single block diagram seen on the bottom right of your poster here the 1130 profiles do show that a flow occurs in the middle of the site for the stream East of the site.
Both the 2d and 3D year T findings demonstrated that the site is heterogeneous and it's geological composition.
On a 3D also shows that the Center of the diagram has a continuous flow resistive area extending in the north, south direction.
Throughout the survey, as you can see the flow is diagonal on our site and it comes from where the stream bed, and the railroad bed cross each other on the 3D ERC profile also does show a preferential flow on the middle the diagram.
Also on the results for the 2d profile, it shows a similarity in the resistive the values indicating, so there is a same type underground material I mentioned before the geologic composition.
And then the boring logs we use which we have three wells in our site, we took the more logs of well one in well for which is well one is on the Northwest side of our site and.
Well, for us, on the southeast side of our site and well one is in the more high resistance zones where your offer is going to be about 46 meters underground and well for.
boring long we have water that's closer to service one to two three meters below the surface and I guess, we want to give a better idea of from one high resistance of the sound to a low resistance on the difference in the geological composition.
and looking at that and did support the theory that we have a heterogeneous makeup at our site and that the underground flow was diagonal across and, overall, the experiment was a success, and I thank you for tuning in we're good day.
Nick Hastings: Okay Mike and i'm going to ask you to facilitate I think brandon wasn't logged on but maybe he did during the timeframe, since i've looked at the participant list.
Mike Apfelbaum: yeah i'm just skimmed through it right now, they don't see his name on Brenda True, there were speak up.
Brandon Day: yeah.
Nick Hastings: i'm here you guys perfect great.
Mike Apfelbaum: What we're talking about yeah good glad you joined us.
Mike Apfelbaum: Any questions for brandon.
Mike Apfelbaum: I had one just in general regarding just the maybe I missed this earlier, but what was, what do you attribute the distance the differences in the resistive of the values at your site where there's associated with your mind.
Brandon Day: Well, mainly.
Brandon Day: big thing was the spacing of the electrode runs we did the two meters spacing we kind of went back and forth on that, if we were going to do a meter or even like larger than two meters, we decided to do the two meters because we had to do to data runs on that.
Brandon Day: Because the first time they really didn't get a good reading so basically it's all in the spacing I would go with.
Mike Apfelbaum: Well there's some that showed up here in the chat box regarding some of your tea.
Mike Apfelbaum: And this is just from a food with regard to the year to you're getting bulk receptivity you may want to change it to the reasons to be a poor water to compare it with the monitoring wealthy if exists.
Brandon Day: yeah we did kind of look at the depth of the water and those wells and compared it to the.
Brandon Day: Findings because we were looking at that stream that too, because the stream, that is not a constant longest or him the water table does dip underneath that so it's again it's a losing streak in that aspect of where the groundwater is located.
Mike Apfelbaum: In another question regarding what was the depth of the sacrificial materials were def to bedrock at your site.
Brandon Day: Believe majority of it was 26 and a meter mark.
Mike Apfelbaum: said to just a superficial thickness you ever.
Brandon Day: Believe on the.
Brandon Day: monitor wells.
Brandon Day: yeah I think it's about six meters deep six meters.
Nick Hastings: Right.
Nick Hastings: Thank you brandon Thank you.
Nick Hastings: And next up, as you can see, before I click it we have in Becker.
Nick Hastings: Who is going to have a recording of his sonar imagery of shoreline to for deposits and beth symmetric mapping at green lake state New York.
Mike Apfelbaum: hi i'm aiden Becker and i'd like to present to foot deposition and bath the matric mapping of green lake state Park, which is located in fayetteville New York.
So during the course of our research, we were hoping to create a high quality beth a metric map of these both narrow deep marrow metric lakes incorporated within this study area.
Which hasn't been done in a very long time, using modern techniques, we have presented here and updated but symmetry map as a result of our research in the top left corner.
And we found an updated Max depth of green lake to be about 175 feet or 53.3 meters and Max depth of round like to be about 159 feet or 48.6 meters.
Another focus of our research concern the two for deposits that can be found around both of these lakes.
We were wondering if we were able to capture the essence of their geometries by using sonar imagery that was also being used to document the symmetry of the lake itself we soon realized that we were able to notice, much more than the two foot that were already known to be in the lake.
We found an additional 14 to fill localities between both lakes three of these localities were even greater than 10 meters wide, whereas we also found 11 that were smaller and less prominent.
Among all the data collected, we also found extensive regions of what a debris that we found to be notable.
on the map in the middle, we provide a stitch mosaic of the perimeter of both of these leaks were green lake is on the right and around lake is on the left and to fill localities are also mapped.
Blue circles represent to further that were known to exist before the research which is about for.
The right diamonds, you see before you represent to further that were discovered through our data collection and we also identified on the map that regions of what a debris that we found to be notable these are located by yellow markers.
We provide a few examples of some sonar tufa imagery as well that was collected, corresponding to locations on the map.
And many of these figures, we also find what a debris that was interesting onto to for deposits, which also seem to be a common occurrence throughout the data collection.
Lastly, we were curious whether there was any correlation between terrestrial vegetation, as well as these two for localities since some tree types are known to prefer specific soil properties.
To investigate this rj guess was used with remote sensing techniques to trace the specific regions of the alternating tree variety surrounding the lakes.
This correspondence, we found between the tree type in tupelo counties was found to be imperfect.
Though for you, through future work, it could involve even more accurate vegetation mapping through surveying techniques, for example.
I would like to personally thank the green lake state park staff for their continued support, as well as soon as we go for their funding, which made the entire project and research possible.
Mike Apfelbaum: Great Thank you.
Mike Apfelbaum: Are you on.
Aidan Becker: Yes, I am.
Mike Apfelbaum: great work.
Mike Apfelbaum: Any questions.
Mike Apfelbaum: Any questions freedom.
Nick Hastings: Here we go find the button to get back out to the default poster.
Mike Apfelbaum: Just one comment your presentation that was pretty pretty useful and thoughtful to do the zoom lens that was very helpful.
Aidan Becker: yeah the text was a little small, so I thought I would zoom in closer.
Aidan Becker: He didn't he made it very easy to follow network.
Mike Apfelbaum: Just regard to the the images so where what are these images of the two foot.
Aidan Becker: So the two foot.
Aidan Becker: are found on the sides of the lake shores So what we are seeing the blank spots i'm going to look at picture l here on the bottom left, so the blank spots.
Aidan Becker: to the top of the image is open, water and to the bottom of the figure is the shoreline, and so the two foot is protruding out into the water.
Mike Apfelbaum: Any questions for him.
Eric Moore: yeah I do have a question I don't know what to finish, could you describe what, to whom.
Aidan Becker: To fuzz are pretty much formations of Sino bacterial microbial life, their structures.
Aidan Becker: I don't really know much about them i'm not really into I didn't really study the G the biology of it but there's a good article by.
Aidan Becker: Laura m demonic it's titled microbes microbiota Lee influenced Look how much the custodian carbonates that goes into more depth about it, if you wish to.
Aidan Becker: look into that more they're mainly.
Aidan Becker: As they're mainly influence because of the gypsum bearing Vernon shale that runs under the lakes and the groundwater from that shale protrudes into the lakes and so it introduces a lot of calcium into the legs.
good description.
yeah.
Nick Hastings: Right all right, well, it looks like.
Nick Hastings: A classmate of yours is next right BAT cleanup.
Nicole Insolia: You were on our projects together so we're both co authors on each other's research.
Nick Hastings: saw that and it's it's not coincidence that you guys get to be back to back so.
Nick Hastings: good collaboration we like that.
Aidan Becker: Yes, alright.
Nick Hastings: So we'll we'll end with your other collaboration, which is mapping of submerged shoreline set genius pond so we'll play the video here.
Nick Hastings: hello, my name is Nicola and Sonia I am from the Department of atmospheric and geological sciences at the State University of New York college at oswego today i'm going to talk about mapping of submerge shorelines at genius ponds.
genius ponds is a unique wetland system or there are many rare endemic species, the stability of water levels is essential for maintaining this important habitat and this research we investigated past shorelines in lowery pond using a mixture of aerial imagery and sonar mapping.
aerial imagery provides a record from 1938 to present and so on our technology was used to detect submerged shoreline features genius pond is located in the finger Lakes Region and it is nested within glacial deposits, as seen in figures, one day, and one be.
In the drone imagery as seen in figure one see you can see some areas that have been more recently submerged.
Our methods for this research, including prior imagery field observations drone imagery with symmetry and sonar mapping.
And now let's look at the results of our mapping figure two is a mosaic of multiple sonar tracks that we use to identify and map submerged shoreline features in yellow is the 2019 pond perimeter and then read or the map shoreline features.
know some of the shoreline features are closer to the modern for one and others are in deeper water.
The blue stars indicate the locations of some example imagery that you can see, to the right of figure to.
The example images a through G in Figure three show a range of shoreline features.
Some show the highest modern shoreline some show lower shorelines and others primarily show lower elevation shorelines in figure for we compare the shorelines, as indicated by aerial imagery with the shorelines we detected using sonar.
Here the Marsh parameters are outlined in green and the pond perimeters in blue, as you can see some of the map shoreline features correlate with those from the aerial imagery.
This validates our interpretation of shoreline features and helps to enrich our understanding of water level changes over approximately the last 100 years.
The shoreline features map for the interior of the pond are deeper and older the combined results have indicated water levels have generally been increasing.
One place where this is especially evidence is in the peninsula, or the Center of the pond which eventually becomes an island and then becomes emerged.
In some cases the rising water levels have eroded shoreline materials and the information for guided by this study.
yields important constraints on pond and wetland extends Accenture essential for the feature management of this site.
We thank the Department of Transportation for funding this research and the New York department of environmental conservation for onsite collaboration, thank you for listening.
Nick Hastings: Thanks Nicole.
Nick Hastings: folks have questions obviously you have two co authors on to answer.
Nicole Insolia: happy to elaborate on any questions that anyone has.
Nick Hastings: I mean, can you give me some example of the of the shoreline features that you're you're trying to map.
Nicole Insolia: Sure, so if so i'm figure to this is the entire punch represented in sonar imagery where a boat a boat was driven around the pond with a.
Nicole Insolia: With a sonar bouncing sonar waves and then bouncing back is the reflected images that can be seen in Figure three and similarly.
Nicole Insolia: Like in aiden's poster the very top of the images is the water, so the interior of the pond and in these images the light blue lines are.
Nicole Insolia: That are traced or the modern shoreline and anything that is a deeper shade of blue.
Nicole Insolia: Is a shoreline we mapped using sonar, that is, has not been previously identified use an aerial imagery and, specifically, some of the ones that are like very navy blue or almost black lines are submerged shorelines that were previously once above water up to over 100 years ago.
Nick Hastings: And you're differentiating those based on the symmetry.
Nicole Insolia: Not i'm the symmetry is in the lower left hand corner, we differentiated them.
Nicole Insolia: Based on how how far away, they were from the modern shoreline.
Nicole Insolia: Because there were based on prior Amor aerial imagery there were.
Nicole Insolia: Already.
Nicole Insolia: defined shorelines that they thought were submerged in prior research and these lines were detected by overlaying sonar on top of previous aerial imagery.
Nick Hastings: I see oh interesting great.
Nicole Insolia: And on the right hand side actually all those green lines and blue lines are lines that were traced from 1938 so every single year, the pond perimeter was outlined to illustrate how.
Nicole Insolia: Every year the prawn perimeter changed as a result of culverts that were constructed um when the interstate I 90 and state route were built in New York.
Nick Hastings: Good event horizon to to monitor the effect of.
Nicole Insolia: terrific Thank you.
Nick Hastings: Other folks have questions.
Nick Hastings: If not, I think that brings us to.
Nick Hastings: Our.
Nick Hastings: Conclusion and boy i'll tell you when when I looked at the schedule and I thought okay 8am or really 7am.
Nick Hastings: till noon on Sunday morning, you know our people really going to stick it out well kudos to everybody on the line here you've done well.
Nick Hastings: Some really great talks and appreciate all of you sticking around to support one another as well, who are giving talks earlier.
Nick Hastings: And with that, I wish you a good conference, make sure to check out what's going on this afternoon and tomorrow and there's a lot of interesting sessions coming up.
Nick Hastings: If you need hints on if you're interested in this type of topic look at the bottom of the page there's some similar.
Nick Hastings: sessions, that you can link to if you haven't built out your own schedule already and I think our tech support and my co moderator Mike and with that, I wish you all a pleasant rest of the day.
Mike Apfelbaum: sounds great Thank you.
Mike Apfelbaum: Thanks.
Mike Apfelbaum: Thanks thanks everybody appreciate it great great information. 1359