Hello and welcome everyone. My name is Dane Menke. I am the digital marketing manager here at Regenesis and LandScience. Before we get started, I have just a few administrative items to cover. Since we’re trying to keep this under an hour, today’s presentation will be conducted with the audience audio settings on mute. This will minimize unwanted background noise from the large number of participants joining us today.

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In order to continue to sponsor events that are of value and worthy of your time, we will be sending out a brief survey following the webinar to get your feedback. Today’s webinar will discuss a site in which a combined in-situ biogeochemical reduction solution rapidly mitigated a threat to a nearby river and saved the client $380 ,000.

With that, I’d like to introduce our presenters for today.

We’re pleased to have with us Scott Scott Connors, senior geologist at Wilcox Environmental Engineering. Scott Connors has over 20 years of experience in the environmental consulting industry as a geologist. At Wilcox Environmental Engineering, he’s involved in all phases of site investigation and remediation, including proposal, bid acquisition, permitting, monitoring, installation, analysis and reporting.

He is responsible for managing large and complex projects from the point of initial consultation and preparing client proposals to the oversight of field work ranging for permits monitoring progress and providing analysis and reporting upon completion to clients attorneys insurers regulatory officials and other various stakeholders.

We’re also pleased to have with us today Brett Hicks central region manager at Regenesis. Brett Hicks has 15 years of experience in the environmental industry. In his current role at Regenesis he leads a team of technical remediation experts across the Great Lakes, Ohio Valley and Southeastern regions of the United States, delivering solutions for sites contaminated with PFAS, chlorinated solvents and petroleum hydrocarbons.

Brett’s team assists environmental engineering and consulting firms as well as responsible parties in achieving their site goals using cutting edge colloidal technologies. He has extensive experience in Institute chemical oxidation, bioremediation, chemical reduction and carbon sorption.

We’re also pleased to have with us today Todd Harrington, Director of Product Management at Regenesis. Todd Harrington is dedicated to driving product innovation that is beneficial to remediation practitioners and the environment and providing industry-leading support to Regenesis clients. He has over 25 years of environmental remediation experience, primarily focused on in-situ remediation.

He has been involved with thousands of contaminated site remediation projects during his tenure Regenesis and has expertise with enhanced bioremediation, chemical oxidation, chemical reduction, and carbon sorption. All right, that concludes our introduction.

So now I will hand things over to Scott Connors to get us started.

Well, hello. Thanks, Dan. I appreciate that. Hi, everyone. Like I said, my name is Scott Connors. I work at Willcox Environmental Engineering here in Indiana and got a pretty cool little project to discuss with everyone today. It was brought to us about four years or so ago. It’s in downtown Indianapolis in what is commonly referred to as the 0153 groundwater contaminant plume. It’s a large number of co-mingled chlorinated solvent sites, dry cleaners, machine shops, you name it. There’s a lot of it so downtown Indianapolis is kind of riddled with a lot of stuff and this was one of the ones that the stakeholders brought us to get a fresh perspective on.

The previous consultant just wasn’t moving along as quickly as they wanted to and they wanted to get some fresh eyes on it. So they brought it to us and asked us to take a look and see what we would do to fix the problem. So we took a look at the site, all the data that existed, and it was a challenge from the very get-go just because of the depth and the length of the dissolved plume. It was primarily TCE and its breakdown or daughter products in the groundwater and it was flowing generally south towards the White River so we have a lot of potential receptors on this one.

The chance for a vapor intrusion along a good number of businesses that the groundwater is flowing beneath and also the ecological portion where it was heading towards the river. So again when we first got the project we kind of stepped back and looked at everything and tried to figure out what our data gaps were. The first portion was the regulatory authority had concerns about the basal portion of the groundwater area, the stratigraphy of the site, and the glacial outwash that we’re in. They weren’t convinced that we had an impermeable aquitard at the base.

So our first portion, we went out there and did some additional investigation with a geoprobe from the area near the river and then all the way up the transector of the spine of the groundwater plume to verify the depth of the aquitard and we encountered it generally between 30 and 38 feet below grade and we found out that it was ubiquitous across the project area. So we knew that the quality of the solvents, again primarily TCE, even if there was any residual free product that it wasn’t going any deeper than that 35, 38 foot zone. So that was our first gap that we had to fill was knowing the vertical extent of the problem.

The existing monitoring well network was fairly well established. We put in a couple of additional wells so we could have longer screens just so we could sample at multiple depths and determine the exact thickness of the dissolved plume. So we went out there, continued groundwater monitoring the site. We switched over to using passive diffusion bags or PDBs to collect our samples. It seemed to be a little bit better, and we could, again, sample at multiple depths. And for a fairly inexpensive groundwater sampling, low flow tends to generate a lot of purge water, so we were trying to minimize costs for our client by switching the sampling technique.

The regulatory authority was all on board and fully in favor. And to verify that we had good correlation from one sampling technique to the next, we did split sampling. We put the PDBs in the well, retreated them about two weeks later, and then sampled those and then also did low-flow sampling so we could verify. We were on the same order of magnitude, so we were very comfortable with the data that we were getting. So we kind of had an idea of the extent of the problem at this point.

And then when we spoke with the stakeholders about their goals for the site, And they said, we want this project done. We want to get closure. It’s been going on for far too long. We want to see an end to the site to get the no further action from the regulators. So that’s what we set out to do.

We started looking at the problem, again, groundwater plume in sand and gravel aquifer in, you know, river outwash, glacial outwash above a nice till plane. While a lot of different remedies would work, they were cost prohibitive. For instance, typical old multi-phase extraction, is it possible? Yeah, but you’d be pumping millions upon millions of gallons of water and probably not getting a very good capture zone. So we were able to rule out a good number of technologies from the jump.

The other issue was the source area. While the business was no longer in operation, so we didn’t have any additional releases, we did still have a continuing source feeding the groundwater. That was in the upper area just beneath the former operations at the factory. So we had absorbed chlorinated solvents, still stuck to the silty clay soil that was a continual source to the groundwater.

So we had basically two issues to treat. The first one, the source area, you cut the head off the snake and eventually the body is going to die. So, we had to, you know, also kind of bisect the body with another technology. So, we looked at its site, kind of, you know, what will work, and then we looked at the cost after the fact, because the marching orders were solved the problem. So, we teamed up with Regenesis to look at the long cigar-shaped groundwater plume that was, you know, had already left the property. We had another teaming partner, TRS, to help us design a thermal remedy for the source.

Based on the silty clay stratigraphy beneath the site, we knew injections wouldn’t work, it was too tight, we wouldn’t get the lateral dispersion and the contact that we wanted so we could take care of the source. So it was a nice opportunity to showcase our ability to do a combined remedy. So we did thermal at the source And we decided upon injections down gradient along towards the river.

So after looking at it and what would work, got a hold of my good friend Brett at Regenesis and said, all right, buddy, let’s have a talk as we had a project to work on together again, which actually kind of made him kind of happy. So we sat down one afternoon over tacos, looked at the site and said, OK, this is what I need from Regenesis. What do you need from me to help you? So, there was a couple of different things that we started to do, because we didn’t know the full thickness of the dissolved plume, so Brett mentioned to me these cool things he had, or that Regenesis had, called flux tracers. So we deployed those in some of our newly installed monitoring wells.

I’ll let Brett talk about that in a little bit. He’s a lot more knowledgeable on their inner workings than I am, but we did use the flux tracers, so we could really get a good handle on the thickness of the groundwater plume. Not just by using PDBs at a couple different depths. We wanted to know exactly where the contaminants were traveling. And we also needed to determine the groundwater velocity or the flow velocity through the site area, because it would have potentially had an effect on our ability to thermally the source.

If the water is moving too fast you’re not going to get the heat that you need to treat the source and it would essentially either fail or we’d have to engineer an extremely expensive system on the up gradient side of the thermal area so we could slow the groundwater flow. Turns out that with flux tracer data we didn’t need to do any additional work in the source for the groundwater because the flow velocity was much slower than we had originally estimated. So that was good news. So the flux tracer data was wonderful.

We convinced the stakeholders that even though it’s suspending a little bit of more money, it’s going to get us some good quality data. And on the grand scheme of this project, what we had an idea the price was going to be, this was a drop in the bucket. So it was either going to be a little bit of money wasted, which we didn’t want to do, or it could be a little bit of money that ends up saving thousands, which it turns out it did.

The data we got from the flux tracers and the additional groundwater data that we had allowed us to reduce the amount of injectables that we needed to purchase from Regenesis and subsequently put in the ground. So less material and less time onsite ended up saving about $380 ,000 off the price of the remediation for the site from what we initially estimated.

So we spent about 35 or 40 grand for the new well install and all the flux tracer data, and we saved 380 and made our stakeholders extremely happy. So we came up with this plan with, again, the thermal and then the injectables with root genesis, had a nice long meeting with the state regulators, said, this is our plan. We don’t see anything else that’s going to work get rid of this problem quickly. They loved the idea. We went down and toured the site and everything went well. They brought out their risk assessors, their chemists, their geologists, the project manager himself, and just had a great plan.

So we had stakeholder buy-in from our client, the client’s council, the regulators there were no objections to the plan then we presented the price to the client they said that’s a lot but you know what if that’s all its going to do it so we quickly got the stakeholders to commit to the price tag and authorized our proposal so we again we sat down with pencil to paper may come up with the plan and next thing you know we’re out there with Regenesis and we’re injecting we I want to say it was end of October a couple years back and we ended up middle of January and got to give a shout out to the guys at Regenesis and their contractors.

Our last day was our worst weather day in Indiana. We had about eight inches of snow and the guys said, nope, we’re going to finish this job today. Which was wonderful. I like seeing that kind of attitude from our field crew. So, again, hats off to those guys that did a real great job and finished the job incident-free. I think we ended up putting in around maybe four, 450 injectant locations. So it was a lot of work and all done safely by a fantastic crew.

The other thing we needed to make sure was that we were going to get the contact that we wanted to get with the injectables that we put in there. So another thing that I think Brad will talk about in a little bit is some of the design verification sampling that we do. You know, if you’re putting the injectables, is it going where you want it to go?

You know, are you getting the lateral dispersion that you want? Brother talked about that, but we were able to prove, we got a shadow of a doubt that we were hitting our target zone perfectly across the board.

And then after the injectables were completed, about a week later was when we turned the thermal system on. So we went right from one remediation technology into the next, which was, again, perfect. This was a very well thought out, well planned project. And we went out, I think it was about 30 days, post injection, which kind of matched up perfectly with the first quarter sampling event. So while we were still treating the source, we were able to do our typical sampling.

We were hoping to get a 30 day sample so we could check to see how quickly the injectants were working. And it was like night and day. Some of the graphics you’ll be seeing here shows the plume at the beginning of the project prior to injectant and then the first quarter post. It’s incredible results. We ended up putting one, two, three, four, five, I think it was six injectant lines perpendicular to the groundwater flow and the samples that came back for the first quarter. For some of them, we went from very high concentrations in the low hundreds parts per billion of TCE to non-detect within one quarter. It was absolutely just incredible.

So we continued to monitor the site. Another one of these maps you’ll be seeing here shows the comparison of the first quarter prior to injection and then the most recent three quarters of sampling. The saying, you know, a picture is worth a thousand words, you take a look at this and you look at how bad the problem was and now you can see how little residual TCE we have.

Now, it’s still out there, it’s not all gone yet, but as the groundwater flows through the barriers that we installed, it’s treating it. So while we still have a little bit near the source, which one would expect, it’s cleaning up exactly how we wanted it to. So, the work we’ve come to expect from Regenesis, we continue to get and they continue to deliver. I think that’s a good little summary of the sites.

I think Brett’s going to expand a little more specifically on the, like I said, the technologies that we use, the flux tracers, how they worked, and the suite of different injectants that we use at the site, because it varied across the site based on the geochemistry and what our goals were.

So I’ll turn the webinar over to Brett now so he can expand a little bit on Regenesis and their work. Thank you. Thank you very much, Scott. I appreciate it. So with that, I’m going to get into a little more detail of the site specifics and some of the technologies utilized here. So thanks Scott for giving a good introduction here.

So just getting into a little bit more background about the site itself. It was a former chemical manufacturing facility that conducted photo engraving processes from the 1950s all the way up through 2004. So a long tenure there on the site, but unfortunately with a lot of the site practices, as we know, can generate some pretty long plumes. And in this case, we generated about a 1 ,500 foot long chlorinated solvent plume headed towards a large surface water body that was flowing through multiple shallow and deep zones within this aquifer.

So there were a lot of challenges presented on the project. And so circling back to Scott’s comment when him and I first sat down to discuss this site over tacos, there was a lot of things that jumped out as we went through this project, but I wanted to highlight a few of the concepts that Scott highlighted as key components of a remedial solution that he was looking for.

We needed a flexible approach from a logistic standpoint. It was a very challenging site in an urban setting, as you saw from the figure earlier. We had a lot of offsite properties, a lot of municipal roadways that we had to work with. We needed to immediately halt the migration of this plume as it was migrating towards the surface water body. So that was a key component there.

We wanted to minimize daughter product formation. We were primarily dealing with TCE, so we wanted to mitigate that in the best way, most efficient way possible without generating daughters, at least the least amount possible. Then ultimately, you know, it needs to be cost-effective. We hear that a lot, and in this case, it was a very large plume, so nobody expected this thing to be a bargain price, but we still needed to be as cost-effective as possible with ultimately achieving our goals.

And the last one was kind of the most important, as Scott highlighted, was rapid treatment. Both the end users and the site property owner was ready for this to be done. This had been going on for quite some time. They were ready to wrap this up. So those are the key ideals solutions that we’re trying to work some, this proposal. And so we’ll get into a little bit of how we got it done.

So the challenge kind of talked about that a little bit. We had a good understanding of kind of how big this thing was, some of the plume features, but we really didn’t have a good understanding of the granularity of it and the inner workings of this plume. So we wanted to really focus in on those migration pathways where this plume is being distributed throughout that zone. And as I mentioned earlier, we also were challenged with the multiple roadways buildings and where we were actually able to even access to install our permeable reactive barriers to cut off this plume. So those are the primary challenges we were facing.

It all starts kind of with the in-situ process here, I want to step-wise through this, but It starts with the design verification testing. So the remedial planning started when Scott and I were discussing it at the very beginning, and that’s just kind of very conceptual. Then when we get into the design verification, we have to verify actually, you know, what are the assumptions that we made? Are they accurate in the field itself? And all this work is done working very closely with the consultant and Scott in this case, because nobody knows the site as well as they do.

So all of this process that you’re seeing here is something that we do working very closely in conjunction with the consultant.

So what is DVT? I want to highlight kind of what that is and what that process looks like for us. So DVT is a process of data collection and analysis, verifying our assumptions in the field, localized high density sample collection, and in this case, primarily trying to identify the contaminant transport zones, the flux zones, where’s that mass moving?

And it’s primarily necessary because if we think about site investigation data, which is really what the site has conducted so far. A lot of that data, you know, it has different roles than what we’re looking for from a remediation design perspective. Site investigation, we’re typically looking for nature and extent.

How bad is it and where’s it going? Who’s it affecting? Which is all very important for us as well, but we also wanna know what’s going on in the interior workings of this thing. And that’s what we really focus on with our design verification. And that’s really just trying to ensure the most accurate and efficient placement of our reagents and making sure they get to where they need to go and ultimately trying to have the most successful project that we can.

For this particular talk I’m going to focus mainly on the the flux tracer and the mass flux vertical profiling tool that we utilize because it was a big player of this remedial program. But first let’s take a look at you know what is mass flux right. So flux is proportional to flow and it really doesn’t matter what it is that we’re looking at, right? It could be the amount of light passing through a given area, through a window, right? So, traffic moving through an intersection. That’s all flux, right?

But from our perspective, you know, we’re concerned with the amount of groundwater and contaminants moving through a given area. That’s what we’re primarily focused on when we’re looking at flux and in this case mass flux. So as mass flux as we’re looking at it from a remedial scale, we’ll take a look at this particular site here. We can see the groundwater here is our groundwater plume is moving through our source zone. We have contamination. What we see here is varying amounts of contaminants are being picked up as that groundwater is moving through there and flowing along with groundwater.

So that heterogeneity in the subsurface and the aquifer is actually allowing for heterogeneous flow of groundwater. So we have less contaminants moving through some areas and more contaminants moving through others. And what we get here, we have a picture showing those varying contaminant concentrations layered on top of each other. So if we look at just individual well samples, we’re not getting a clear picture of what that actually is going to be across our site. We’re just getting a general average, right?

So it’s kind of giving us a complete picture of our conceptual site model of the area that we’re trying to remediate.

So why is that important? So why is measuring mass flux important? It’s extremely important because, as a lot of folks will realize, 80% of our mass is flowing through only 20% of our aquifer. Identifying the mass that moves is really crucial to fully understanding and being able to remediate our mass and delineating those vertical zones that are ultimately controlling the size and shape of our plume.

Permeable reactive barriers, which is the tool we utilize in this particular instance, are extremely sensitive to contaminant mass flux in relation to both short- and long-term performance. Without fully understanding the mass flux and where it’s moving, we run the risk of underdosing or not dosing our PRBs accordingly and jeopardizing the performance of our PRBs time.

Getting into the design verification program that we implemented specifically for this particular project, our primary objective was to identify those flow channels throughout our treatment zone, and we did this in a few different ways. First, as Scott mentioned earlier, we collected a baseline groundwater geochemistry round by installing some temporary piezometers and new monitoring wells to establish a baseline.

We also collected soil cores to confirm our lithology. As it changed from the source site toward the river, we noticed some undulation in the aqua target that Scott mentioned, so we needed to identify those fluctuations to target the intended interval.

Lastly, we utilized flux tracer devices. These are stainless steel canisters pre-assembled with granular activated carbon and deployed into existing monitoring wells to help us understand the Darcy velocity and mass flux flowing through our treatment zone. We installed five 15-foot devices throughout the center of the plume, one in each barrier location from an earlier figure, with one passive flux meter per barrier.

The results of these devices were significant. They allowed us to identify the mass flux zones and confirmed assumptions about groundwater velocity. Originally, estimates suggested a velocity of 1200 feet per year, but our flux tracer devices revealed a more accurate velocity of 300 feet per year, allowing us to dose the PRBs accordingly. This also optimized our vertical dosing, helping us concentrate reagents in zones with higher contamination and saving resources in areas with lower contamination.

Additionally, horizontal delineation reduced the overall barrier length by 44%, saving approximately $380,000 for the client. Convincing clients to invest upfront for savings on the back end is always beneficial.

Following our design verification, we moved to a full-scale approach with a two-tiered remedy: an on-site component near the source, using a slow-release electron donor and soluble ferrous iron, and an off-site component with colloidal activated carbon and sulfidated micro ZVI for the four barriers.

As we moved into field operations, our conceptual model continued to evolve. We utilized pre-injection soil cores and temporary piezometers in each injection zone to monitor distribution during injection. This allowed for real-time groundwater sampling and adjustments as necessary. Post-injection, we conducted a confirmation core to check for the desired vertical and horizontal distribution in our target interval.

This process, conducted in late 2022 and early 2023, involved a two-tiered approach with on-site ERD and off-site colloidal activated carbon. The work spanned 56 days, including winter in Indianapolis, as Scott mentioned earlier. We were pretty fortunate with the weather in this particular application outside of a couple snow storms, but overall we were pretty fortunate with some pretty decent weather in the winter.

But we applied about 110,000 gallons across the site in those 56 days. And a highlight here on this table here below is just to show the undulation and the difference of our treatment intervals through the four PRBs as we moved from the site down to the river. So there was a lot of changes throughout that zone that was very important for us to be able to confirm throughout the program of each PRB location to make sure that we were hitting our target interval and placing that remedial fluid where it needed to go.

So getting into the results Scott briefly touched on some of these. I mean they’re really looking really good and pretty impressive overall. And three months post application, you know, we went out and collected our first round. We saw immediate dose response, 80 to 100% reduction in total VOCs throughout our target interval along that plume. Then as we start to work through, you know, this has been sustained for three quarters and counting at this point.

So we’re continuing to see the degradation occur, and this plume is really shrinking up and the overall threat to the White River has been mitigated overall. So this is a combination slide of all four before and after photos, so I think they kind of speak for themselves. The results are really impressive. The client’s happy, regulatory body’s happy, all good things there.

So in summary, I want to go back and take a look at the original goals that Scott and I outlined at the very beginning and, you know, how we can check the boxes for all of these and developing a flexible approach utilizing our PRVs that allowed us the flexibility to minimize our disruption to a very busy area of Indianapolis.

The results show we’ve been able to halt that plume migration to the river. It’s no longer a threat to that river. We minimized the outer product formation. We not only eliminated that TC, but we did not see any outer product creep. All good things cost-effective. We ultimately saved the client $380,000 in the long run. So it Yeah, everything’s looking really good with the rapid seizure of that plume. Regulatory body’s happy, and we’re headed towards the monitoring phase of this program. So hopefully we’ll be updating everybody soon with a closed site and onto the next one.

And with that, I will turn this over to Mr. Harrington to wrap us up and get into the colloidal technologies a bit. Thank you.

All right. Thank you, Brad, for that great information and case study. I want to give a very abbreviated overview at this part of the presentation of the technologies used and some of the highlights before we get into the Q &A.

And what I want to talk about first is PlumeStop, which is kind of the workhorse for the barriers that we talked about. It’s a colloidal activated carbon. It’s very small, one to two microns in diameter. It does give a view of something like an ink, as shown in the jar on the right, but what’s and what was used very effectively on the sites that we talked about is that it’s small enough to move through the pore space of an aquifer and even encode that aquifer, so it gives a nice even coating.

The comparison shown in this, you know, we’ve used this before, but this set of images is the plume stop moving through under gravity flow under low pressure in a sand column compared to pattern-activated carbon on the right. So this is excellent for creating a system. Now once in place in the subsurface, it does absorb out contaminants. You know, that reduces the contaminant concentrations very quickly, it minimizes downgrading and flux, and in of itself can have a multi-year lifespan.

But over time, what you really want to do is you do want to destroy the contaminants that are adsorbed to it to extend the lifespan even farther and prevent breakthrough. And the first way that we’ve done that in the past. It wasn’t the primary method we used on this case study, but we do use enhanced reductive dechlorination with electron donors.

Now, I’ll talk about an electron donor we did use in the source area in a bit called 3DME, but in the barriers themselves, we can regenerate. First, we’ve done it through biodegradation, and when that happens, the destruction of, say, PC or TCE, freeze absorption sites, where those new incoming contaminants consorb over time. Now, the same thing can be done using a non-biological approach, say using the iron product that we talked about, the S-micro ZVI, through chemical reduction via beta elimination.

So this is a commonly used graphic, and I’m gonna put it up here just for the benefit of our viewers who may not be as familiar with either biologic dechlorination or abiotic dechlorination. On the top row, that is the classic sequence of the reductive dechlorination process as PCE moves all the way to, say, innocuous ethene. And this is typically done by adding an electron donor and or adding also for stimulation, a microbial consortium. We have one called BDI that I’ll highlight in a minute.

So that is the biodegradation pathway. You can also go through beta elimination, which is the use of our iron product. Now, what that did in the barriers is it sidestepped a daughter product formation. The top row dechlorination through biodegradation can be prone to the buildup of daughter products, which could break through a barrier, whereas an S-microZVI is extremely fast at degrading PC and TCE and sidestepping that daughter product formation.

So the product that was used more in the source area It wasn’t the main highlight of our talk today, but I just wanted to mention that it’s an excellent product that’s been out for a number of years. It can be used with the Plum Stop or the ZVI. It’s a three- to four-year lifespan, three-stage electron donor comprised of lactate, polylactate esters, and free fatty acids. It’s an excellent distribution, and we’ve used it very successfully.

We often pair this with a bacterial culture called Biodichloroenoculum Plus. Again, this has been out for a while. The use of such a culture has been ongoing for a couple decades. We find it very effective as well to go ahead and add this anytime we add electron donors. And that’s what was done on the upper source area and some of the initial parts of the barriers that we had in this case study. But it’s relatively inexpensive. We don’t put a lot in and it’s a really good safety factor.

But the heavy lifting for destruction of what we talked about today was S-micro ZVI. The challenge with the ZVI is that when you just add iron, it rusts, and when it rusts, it passivates, and you have a decreased persistence and less treatment of the contaminants. Our answer has been to sulfidate the surface, and what does that mean? That means to add an iron-sulfide outer layer.

I’m not going to get into the specifics of how it’s done, but suffice it to say that once you add a layer, it’s a protective layer that prevents the iron from rusting. It minimizes the reaction rate with water and maximizes the amount of electron transfer rates that can be used for dechlorination of the contaminants. So it has much greater longevity and reactivity. In fact, in a lab study that we did, we can see that 150 micromoles of TCE on the vertical axis is completely destroyed in about 15 days, whereas the same type of iron in the same situation barely destroyed the TEC at all.

And so what we’re finding is that S-MicroZVI is about 30 to 50 times more reactive than bare iron and still has a four-plus year longevity.

All right. I’m going to just show a couple slides here that show the synergy of these products, you know, that show how important it is to put them together. So just making the case, as I’ve done in the previous slides, that with sorption only, what we’re looking at is actually the model output of plume force, which is a model that we have internally that we use to model dose rates and performance, et cetera. And we can explore synergies of our products.

This is a centerline output for this model that shows concentrations on the vertical axis in micrograms per liter horizontally, its distance in feet and the gray bar is a barrier. This could be like the barriers that we talked about in the case study today. As you can see, let’s say we run this for seven years at 200 feet a year. We have a solvent plume going from left to right through that barrier and out of it that it’s insufficient in and of itself through sorption only to stop contaminants from making it through over the long run.

So that’s why, because it doesn’t effectively absorb everything over time, we added the S-microZVI to our barriers or to the case study that we did.

And what you can see right here is that because the S-microZVI has 30 times the reaction weight of normal iron, you can see the PCE in blue and the TCE in orange drop quickly in concentration. In fact, no breakthrough whatsoever. And really, because it’s sidestepping the generation of monochloride and DCE, you’re also not seeing any of those products appear in that barrier, and it’s completely effective on its own there.

Now, one thing we have the option to do with, say, 3DME is there could be situations where we have a lot of biotin chloride coming in, we have a lot of DCR already coming in, and that would be a situation where we would add electron donor and even the biotin chloride inoculum to really give sort of the state-of-the-art most highest performance that we can get.

And you see in this barrier here, there’s absolutely no concern of breakthrough by any of the parent or daughter products, superior performance of the bona chloride. So just a snapshot of what we can do putting things together.