PetroFix Webinar

Dane: Hello and welcome everyone. My name is Dane Menke, I am the digital marketing manager here at REGENESIS and Land Science. Before we get started today, 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. If the webinar or audio quality degrades, please try refreshing your browser. If that does not fix the issue, please disconnect and repeat the original login steps to rejoin the webcast. If you have a question, we encourage you to ask it using the question feature located on the webinar panel. We’ll collect your questions and do our best to answer them at the end of the presentation. If we don’t address your question within the time permitting, we’ll make an effort to follow up with you after the webinar.

We are recording this webinar and a link to the recording will be emailed to you once it is available. 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 presentation will discuss validating the role of PetroFix technology for the remediation practitioner’s toolbox.

With that, I’d like to introduce our presenters for today. We are pleased to have with us Jack Sheldon, senior remediation specialist with Antea Group. Jack has over 39 years of experience in the fields of environmental microbiology and remediation. He has a B.S. in bacteriology and public health and an M.S. in environmental and industrial microbiology from Wagner College in Staten Island, New York. His current role, he advises on remediation technology selection, performance, and optimization across the U.S. and abroad. His key technology areas are bio-remediation and chemical oxidation. Jack has authored numerous papers and posters and coauthored two best-selling books on bio-remediation.

We’re also pleased to have with us today, Todd Herrington, global PetroFix product manager for REGENESIS. Todd directs the expansion of the new hydrocarbon treatment line in the global marketplace and provide industry-leading support to REGENESIS customers. He has over 24 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 at 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 Jack Sheldon to get us started.

Jack: Thank you very much, Dane. And thank you to all of you for joining us here today for this exciting webinar. I would say that what I’m going to do is give you the consultant’s perspective on taking a new technology and putting it through the paces to determine whether or not it’s suitable to put in our practitioner’s toolbox. In other words, does it become one of our regular technologies to use from site to site? So, once I’m done with my portion of the presentation, I’m gonna pass it along to Todd, and he’s gonna expand on a couple of the points that I make. So we’ll look forward to that as well.

So let’s start out with the fact that carbon sorption products, injectable ones I’m talking about now, are part of people’s toolboxes at this stage of the game. These products have been around for more than a decade. There are several different products that are in the marketplace. They can be a variety of different size carbon particles from as small as one to two microns to up to 70 microns or so. All of these products are characterized by the fact that they bind to aquifer solids and they attempt to establish a biodegradation site. And then lastly, for them to work in an optimal fashion, regeneration has to occur so those carbon sites, again, become available to sorb contaminants and to create a degradation environment. Now, some products like REGENESIS PlumeStop are celebrating their seventh anniversary in the marketplace. PetroFix is a little bit newer to the game. And there are also some other products that have emerged on the market within the last couple of years. So the market is pretty dynamic and this is a well-established technology now.

And I think people understand the carbon aspect of it quite well, in that different groundwater constituents sorb to carbon preferentially. And I think people understand that. And they understand the whole concept of regeneration of carbon. I think the biodegradation piece can be a little bit of a question mark for certain people, but I can tell you as a microbiologist and looking at a lot of third-party information, that the whole biodegradation site and degradation game on the carbon particle is one that really occurs. And most people think that, you know, microbes sit in the groundwater and are just kind of floating around. And yeah, that’s true. There are microbes that are doing that, but the vast majority of the microbial population resides on the soil particles or when you put carbon in the subsurface, sits on the carbon particles or within the pores of the soil or the carbon.

So there are these natural degradation sites that are established. It’s a little bit hard for some people to accept, but in reality, microbes love to attach. And as a result of that, they form these thin biofilm, whether it’s on soil or it’s on carbon particles and they’re perfect bio-reactor sites for degradation to take place. These biofilms are actually layers of various microbial communities that interact with one another and you can have very diverse microbial populations within those biofilms. And nutrients come in and out and contaminants come in and out, and they become a very dynamic site. So that’s very, very real when one in place is carbon in the subsurface.

So the rest of my agenda here is, well, why PetroFix? Well, first from Antea Group’s perspective, but also probably from yours as well. I’m then gonna talk about the often forgotten electron acceptors. You know, we spend so much time talking about the carbon itself. Let’s not forget about the electron acceptors that come along for the ride. And then lastly, we’re gonna delve into four case studies that I’ve selected, very briefly and not so data-focused, but more characteristic-focused.

The Antea Group has over two dozen PetroFix site projects currently. And I selected four of those that I think are a little bit different and will make for some good discussion here today. So, why PetroFix? Well from our perspective, I think it is a product that is well-suited to low to moderate mass scenarios. That doesn’t mean we haven’t cheated it a little bit in some cases and kind of pushed it into a little higher mass scenario and have had good results. But you’ll notice what you don’t see on here is LNAPL. And if you are actually considering PetroFix for an LNAPL site, then I think that’s a conversation you have to have REGENESIS before you push forward on that. In our broad array of projects right now, we do not have a single project that utilizes a PetroFix with LNAPL.

Also from our perspective, it’s easy to apply PetroFix in grids, in barriers, in excavations, and… They always hesitate to use the word easy because even the most simple things in our industry can be challenging. And when I say easy, I mean, just in terms of it’s ability of the PetroFix to get into the subsurface and to stay there and to minimize or eliminate daylighting, I think that’s a really valuable characteristic. Probably the most important one is that PetroFix is applied on tight spacing. And let’s face it, those of you that are consultants out there like myself, we like to cheat the radius of influence quite often if we feel we need a seven or eight-foot radius of influence, well, don’t we all have a tendency to wanna push it to 10, to maybe eliminate a few injection locations, maybe just cheat it ever so slightly? Well, the nature of PetroFix is such that it drops out a solution very, very quickly within close proximity to the injection points so that tight spacing becomes a tremendous asset with this technology in terms of creating more complete distribution and avoiding gaps in between injection points. I think that’s critical to success on any given project.

So again, why is this product useful for Antea Group? Well, we love the concept of it providing a subsurface filter, you know, the ability to stop a plume in its tracks and be able to allow degradation to do its job. Also, we love the fact that it’s injected under low pressure. You know, as I said earlier, carbon products, some of them are slurries, some are liquids, some have to be injected under high fracture pressures. Well, this is one of those that’s injected under low pressure and low flow. So it goes into the sub-surface easily. And the fact that it’s infrastructure safe, and we work around a lot of utilities, a lot of other types of infrastructure where harsh chemicals just won’t do the job. So we need something that’s more benign and PetroFix fits that bill. Then the concept of managing back diffusion and just, you know, the movement of contaminants in and out of the soil matrix. To have something in place like PetroFix to be able to manage that condition becomes really valuable on a site, prevents rebound from occurring, and really will help drive a site to closure.

And we like the fact, you can get fast results with PetroFix. It’s not uncommon for us to see rather immediate results. And when I say immediate, within 30 days of injection or 60 days of injection, and then to ride that out a little bit longer until we actually reach our desired endpoint. So that’s a nice attribute of this technology as well. And of course, the electron acceptor package is one that I think is really useful for many, many sites. The fact that REGENESIS has incorporated nitrate and sulfate together, that is a powerful electron acceptor package. You know, we’re all conditioned to think petroleum and oxygen, and that’s well-suited to many sites. But that electron acceptor package that uses both nitrate and sulfate, that can really be a strong electron acceptor or a component and really drive degradation.

So how about the electron acceptors? Well, let’s get into that for a minute. My firm, Antea Group, has pioneered the use of sulfate for many, many years. One of my former colleagues, in fact, was one of the original patent holders on the injection of magnesium sulfate or Epsom salt for petroleum hydrocarbons. And we were very successful with that technology and being able to apply it across the country. Now, nitrate and sulfate are naturally present in the subsurface at many sites. They’re also very soluble. So when you add them, you can add them in relatively high concentrations. Most sites abound with sulfate-reducing bacteria. It’s very rare that I test the microbial profile on a site and don’t find robust populations of sulfate-reducing bacteria.

Now, nitrate or denitrifiers maybe not quite as abundant on sites, but the interesting thing about nitrate as a chemical is that both aerobic and anaerobic bacteria can utilize it. So once it goes in the ground, it can be readily utilized. Also some of the more recent literature suggests that sulfate-reducing bacteria use nitrates when their environment becomes stressed. So actually the nitrate, not only is it a powerful electron acceptor but it can also be used by the sulfate-reducing bacteria as protection so that they can maintain their population, and also be available to create degradation. And the use of nitrate and sulfate has been proven at hundreds of sites. Mostly sulfate, it’s a little bit harder to get nitrate approved in some scenarios, but certainly been used in Canada. We’ve had been able to get nitrate approved in various states at various times across the years. So the combination of the two again is quite powerful.

So just looking at a little bit of chemistry up there, this is toluene that we’re degrading here in both these cases, just to give you a glimpse of what sulfate reduction looks like from a chemical standpoint as well as nitrate reduction. A couple of things with sulfate to consider. In theory, from a stoichiometric standpoint, you produce hydrogen sulfide as part of the sulfate reduction. Well, in fact, we found that even with very low iron concentrations, you can tie up that hydrogen sulfide as iron sulfide never see the hydrogen sulfide. So that’s something that’s important to keep in mind with that particular degradation mechanism. As I mentioned earlier, magnesium sulfate has been used commonly as has calcium sulfate. So those are two forms that you’ll commonly see injected into the subsurface.

Then if we look at nitrate reduction or denitrification, one of the big concerns there has been the formation of nitrate. And that does happen from time to time, but that can be managed with the dosage of the sulfate and the nitrate that you put into the subsurface. So all those things can be combatted once you know what sort of condition that you’re working under. I never give a webinar or a talk without mentioning molecular biological tools. And I think they’re highly relevant when we’re looking at a PetroFix site as well. Whenever budget allows and whenever a scope of work allows, you should incorporate microbial profiling into your game plan for the site. You can learn so much from the microbial profiling, whether it’s at the microbial population level or the gene function level, or even digging deeper and establishing that degradation is occurring. And there are many, many tools that you can utilize. And there are even some newer ones that are coming along, which include biosurfactant detection. Yes, in fact, microbes do create surfactants that they actually use to degrade constituents off of soil or off of carbon particles. So those types of tools are evolving and they’re available to you in the marketplace.

So let’s jump into our case studies now from one to four here. And they’re each, as I said earlier, a different type of site. So here’s site number one. This is a PetroFix application in an excavation. If you look on the slide here, you’ll see the field staff. They’re preparing to inject a bit more of the PetroFix and you can actually see the field staff painting the walls of the excavation. This is at a former convenience store site. You can see a water truck in the background and some of the basic mixing setup and application technology that’s being used at the site. So why might you ask, are we treating this excavation all the way to the surface? Well, throughout the history of this particular site, there has been contamination at the surface. And in this case, we did dig a little bit into the water table. So we decided that we would coat all the way from surface down into the water table and even the base of the excavation as part of this project.

So how about a few more details on this site? This site at about a 2000-square-foot excavation area, we pulled out roughly 1300 cubic yards of soil. This is Iowa so soils tend to be very silty or very clay. In this case, it was clay soil. Water would infiltrate at the base of the excavation very slowly and at the base of the walls very, very slowly. So we did not have a major scenario where water was rushing into the excavation. We did have benzene at a maximum concentration of a little over 16 milligrams per liter, but generally on average in the excavation area and just outside of it, the average concentration was about a little over a milligram per liter in groundwater. We had to pull out all the wells on this site and re-install the wells in the excavation and just outside. It was not a very large site. In fact, the excavation almost went to the property boundary with just a little bit of room to spare. So the site was quite small. And in this case, we had a target concentration of 290 micrograms per liter of benzene, which was determined on a risk basis.

So as far as the application went, we had originally intended to use RCA pellets and have oxygen generated within the excavation. That has more or less been a best practice for us for years and years, and we decided to still continue with that. So we put in 1100 pounds of RCA pellets to generate a little bit of dissolved oxygen within the excavation, but we added 3,600 pounds of PetroFix and we sprayed that again onto the walls and the floor of the excavation. And that’s quite an interesting little process.

So how did we do? Well, we hit that 290 micrograms per liter benzine concentration within 19 months, had two wells installed within the excavation and three wells installed just outside the excavation. Wells were very, very close to the excavation. I think it would be unrealistic to expect any sort of dramatic movement or effects from the amendment very far out of the excavation footprint, but we did see within a couple of months after application, some of the nitrate and the sulfate arriving at the closest wells, not only the ones in the excavation but just outside, which were just a few feet up to seven feet away. And we did start to see that occurring. And then we also saw the concentrations of microbes as measured through quaternary petroleum molecular biological tools increasing by two orders of magnitude. So I think that’s a pretty positive result and in this case, closure was achieved.

So some highlights. So water seeped into the excavation shortly after application. I think that’s a good thing that helps mix up conditions a little bit, helps wet that PetroFix amendment. And we tried a variety of different types of nozzles. We went to the hardware store, tried some different ones. We even tried to take a drum of the PetroFix and have the excavator just kind of wave it across the bottom of the excavation and paint it using the excavator. You know, I don’t think those methods wound up as best practices overall since we were experimenting a little bit, but since that time that this project was completed, REGENESIS has developed techniques to better spray-apply the PetroFix technology. And that’s really exciting and it’s evolved very nicely. So again, the excavator was used in that capacity to help distribute the PetroFix. And as I mentioned, we did observe actual impact from the PetroFix just outside the footprint of the excavation, which I think is pretty exciting. And this was the first PetroFix site in Iowa, and it was the first excavation application using PetroFix in the country. So we’re proud of it and the fact that it did achieve our goal, which was closure.

Case study number two. This one is what I would call a stubborn site. Everyone on this call has those, right, that site where you’ve tried four or five different things and there’s one or two wells that are keeping you from closure. You know, no matter how much delineation work you do, or how much you go out with a MIP to try to pinpoint the transmissive zone and get amendment to it, that well or wells just continues to hang on. And such was the case here at this site in the state of Washington. This was a service station site with leaking underground storage tanks and dispensers. This was more of a silty sand scenario, little better permeability. There were some interbedded clay within it. And in this case, the GRO concentration, gasoline range organic, was a little bit over 10 milligrams per liter as a maximum, and almost 3.5 milligrams per liter as an average in the treatment areas. A little bit different contaminant scenario than the prior site I talked about. In this case, the GRO target in the state of Washington was 1000 micrograms per liter.

So getting a little closer look at it, this was just a simple six direct push point grid. Four hundred pounds of PetroFix were applied, a little over 1300 gallons of injectate. The area was small as you saw in the original photo, just 400 square feet. We had about a 10-foot vertical interval that we injected in. And so the process was very straightforward and very basic, but this one well at MW-4 was keeping this site from being closed. And this station was still active. So we had to work around a lot of the logistics out at the site. Well, I’m happy to say on this one too, within 18 months, we were able to reach a closure for it. And this site had been in remediation for greater than nine years. So many of these service station sites have had countless rounds of remediation with multiple remediation technologies. And yet, it took a very basic injection of PetroFix to get it over the hump into the home stretch and achieve the regulatory goal.

It’s also interesting. I can’t tell you too many sites I’ve ever done historically, and I’ve been at this for almost four decades, where there isn’t some level of daylighting that occurs on the site. It might only be a half-gallon or a gallon, but in this particular site, there was no daylighting whatsoever. And you don’t have to clean up a little black ink-like material from the surface, that’s all the better. And that proved to be a very important point on the site. Washington is a very stringent state. It’s amongst the most difficult regulatory environments that I work in. And we were in fact able to get the nutrient package approved here. And I think REGENESIS has the ability to provide the nutrients as just nitrate or just sulfate, but preferentially, if you can apply that nutrient package together, as I pointed out earlier, nitrate and sulfate is a powerful combination, will help get you to the finish line.

So now we’re onto our third case study in the mix here, which is a former manufacturing site in North Carolina, which had a fleet of vehicles. So they would fuel up at a dispenser area on the site. Again, this is an active manufacturing site. This is more of a sandy-loam material. So again, a little bit of a different injection scenario. This was another site where we applied a grid of PetroFix. So we had on average, a benzene concentration of 20 micrograms per liter, total xylenes of 669 micrograms per liter, and naphthalene at 140 micrograms per liter. So a little bit of a different contaminant mix here. And the targets were 1 and 506 micrograms per liter respectively. So we have to get down to some pretty low numbers, particularly with the naphthalene and the benzene. So that’s very, very challenging and probably out of the reach of most technologies.

So why such stringent levels for this site? Well, there are some water supply wells within relative close proximity to this site, and that was a huge driver in the overall mix. So the ability to apply a technology that not only could provide treatment but also kind of stop the plume dead in its tracks, that was really valuable to us. So again, some more PetroFix application details here. This one was about 1900 square feet, the injection area, a little more shallow than the prior site I showed you, from 5 to 15 feet. So again, a 10-foot injection interval, but a bit more shallow. We used about a six-and-a-half-foot spacing on this one. And I can tell you of the couple dozen-plus sites that we’ve done, that’s been our maximum spacing on any of the sites. Typically, we’re down around four, five, five and a half, maybe six on certain sites, but this one was about as far as we pushed it in terms of spacing. Put in about 4,000 pounds of PetroFix, a little over 16,000 gallons. And this one had 45 injection points. So a little more extensive injection work for this site.

But one of the nice things we were able to do, this particular project manager on this site, he’s a data collection guy and he has collected geochemistry and microbial profiling throughout the years. This site has had a variety of different remediation technologies applied, including sulfate, which we did have good success with at the site, but several other technologies were applied as well, but we just didn’t get to the finish line. So because our project manager is a data collection guy, he built into the monitoring plan a collection of soil cores. So you can see on the right, the distribution of the PetroFix across the injection area. And I think that’s a really beautiful core in terms of from black, from top to bottom, to be able to show that we have really good distribution out here at the site. And that’s what makes the success. You had a very checkered or modeled distribution, I would say that the chances of success are quite questionable. But in this case, when you get such distribution like that, which is relatively uniform, you’ve got a real likelihood that you’re gonna see results.

This one, I do have a little graph for, and this is characteristic of a lot of our PetroFix sites where the black arrow to the left in the graph is the point at which the PetroFix was injected. And you can see what happens. The bottom falls out. In this case, after about 30 days post-injection. And you can see the concentrations of BTEX and naphthalene just plummet at two wells within the injection grid. And then you kind of teeter around for a while through a series of injection events. And this is not one I’m gonna tell you that we’ve achieved closure yet, but the good news here is that we’re making progress. We’re monitoring the geochemistry so we can see the breakthroughs of nitrate and sulfate. We’re also seeing the microbial profiles and how they’re changing. And this is one that I hope to be able to report in the coming months that we’ll get to the finish line on as well. But this is very characteristic of what a graph looks like from PetroFix site to site. Now, that first lag period might be 30, might be 60 days. It might even be 90 days for some sites, but the bottom line is you get the bottom dropout and then you get this nice little gradual march to your endpoint.

So a couple more performance highlights here. Again, my project manager here, he’s a data collection junkie and he’s tracked the microbes for years. So I think we’re gonna be able to learn something interesting from that. This site has been remediated since 1985. And wouldn’t that be a luxury for our client to see this thing close? That’s a long time for remediation and there’s lots of sites out there that are in that boat. So, perhaps PetroFix is the answer for several of those. This is another site where we had minimal daylighting, not no daylighting, but minimal daylighting. Gallons, not you know, tens of gallons or hundreds of gallons, anything like that, but a little bit of daylighting at the site, but nothing major that we had to deal with. One unique aspect of this site was that because the site is located in an area that has some high profile PFAS sites, we were required to analyze the hydrant water we used to make up our injectate to make up the PetroFix solution. And they only had us analyze for a couple of PFAS constituents, PFOA and PFOs, PFOA, PFOS. And fortunately, they were not present in that hydrant water. So that was a good outcome. That is the only site that I can say I’ve been asked to analyze for PFAS for my injectate to date, but that may change in the future. And this was in fact, the first PetroFix site in North Carolina.

So the last site is a real simple one, a relatively straightforward one. So what happens when you put PetroFix into a barrier with very low BTEX concentrations? And this is a site in West Virginia. If you look in the background there at the basketball hoop, this looks like a residence, and that’s exactly what it is. It’s a small residence that used to be a former gas station. And in fact, we have a very simple task out there, and that is to create a barrier outside of one well that has 45 micrograms per liter of benzene in it, and keep that benzene from migrating offsite. So pretty straightforward. This is a little bit more of a silty clay matrix. We had a little more daylighting on this site, but not terrible in any stretch of the imagination. And the job here was again to prevent the migration of benzene off the site.

So this took about one year to meet the goal. We got a little bit of the PetroFix that actually found its way temporarily into the well. I said no daylight in here. I think in actuality, it probably better said as minimal daylighting. We did achieve a closure on it. And this is another one of those sites that for over 10 years had been remediated using a variety of technologies, including Hisco and bio-remediation, but just not enough to get it to that home stretch. So, happy to say, this was the first PetroFix barrier in the state of West Virginia. It did its job. And I think we’re very eager to see what PetroFix will do in the future for the other sites that we’re looking at. And we currently have sites with hundreds of injection points and we have more of these smaller sites and they really run the gamut from individual groundwater constituents like benzene to more complex mixtures of different constituents within the groundwater. So we’re eager to see where PetroFix takes us as time goes on, but without question, it’s been established as a real tool within our remediation toolbox. So with that, as we transition to Todd, I’ll just leave my contact information up for a bit, and I’ll look forward to joining you for the Q&A session in just a little bit. Todd, all yours.

Todd: Jack, that was great. Thank you very much. I was excited to hear you run through that, as hopefully our clients were. It’s been great working with you and glad you were able to join us today. I’m gonna talk probably around 12-13 minutes hopefully, to wrap up. What I wanted to do was spend some time just highlighting and emphasizing maybe some key points, some questions that I was imagining that people might have on the back end of Jack’s talk. And then certainly, we’ll have a healthy amount of time for some Q&A you know, for this webinar. All right. So, Jack did a great job really already emphasizing the points that I had put together here. Some of the really the key benefits of PetroFix that I think are gonna help, you know, be attractive to most consultants. And really modifying the aquifer so that you’re using this product to turn it into a purifying filter that’s evenly distributed so you can get those fast and persistent results so you can treat back diffusion.

And this cartoon on the upper right, is really what you want your subsurface to look like where you’ve got PetroFix material distributed in the aquifer itself. And if you take a core and pull that out, like Jack showed on at least one of the sites, a core of uniform black there, you know, that’s where the magic happens. And the ability to last long-term for back diffusion is truly something that does perform over time. And so I would say in addition to Antea, we’ve just been seeing positive results were wide, you know, it has been applied in 39 states right now, 365 sites. I like to point that out, not really just bragging about it, but really just also saying that you know, you may be thinking this through in one of your states and, you know, wondering if it’s been applied there, how easy is it to get it through the UIC process. Anything like that. We can help with that, or more than likely, it’s already been approved. I guess the gears have been greased already, so it may not be too difficult for you.

However, Jack’s right. We’re seeing these fast results across the site. When you get good distribution, it could be as much as one or two orders of magnitude within the first quarter or two often to non-detect. I do wanna emphasize though that one thing that happens from my side being a product vendor, you know, I think people look to us as helping with a good design, having a good product, sometimes the application itself, and getting this through a coating in the upper right, you know, getting your aquifer looking that way, if you can do that, the results are gonna come in. And so there’s best practices for that. And I did wanna highlight just because it happened recently, about three weeks ago, we did a webinar on best practices for PetroFix. And some of those best practices we’ve learned together with Antea, to put those together because we’ve done so much work with them.

So I just wanted to point people, you can find that on our website. Because Jack was, you know, mentioning the electron acceptors, I wanted to just let people know that yes, PetroFix does ship with electron acceptors. I was more interested in the second point. It ships in totes and drums, but with each shipment, there is a… For each drum, there is 20 pounds of electron acceptor, roughly 50-50% sodium nitrate and ammonium sulfate that are applied in there, or for a tote, you’re gonna get five of those. Now there’s also some calcium sulfate dihydrate that’s mixed right in. And so we have a combination of slow and fast release electron acceptors. Now, this is a really good amount to start with. When you get companies like Antea with their expertise, you know, certainly, they can vary this themselves outside of this, but generally, this is a really good starting point for most people.

And so, what I wanted to show here is just to recap for those of you who may not be that familiar with PetroFix, say, you’re jumping on this webinar today, and it’s a little bit new to you. The main reduction that we’re jetting when we inject the PetroFix and get that coating is that we are taking a particle that’s the size of a red blood cell. The PetroFix is a coconut carbon that’s milled down to such a small size and it’s been modified with a polymer chemistry, a dispersant chemistry that allows it to transport through the subsurface. Jack did mention, he said it doesn’t go that far. What it does is it does go where you need it to go under pressure but then it will start to adhere to the soil. And you can see in this picture on the upper right that the PetroFix particles themselves are on a sand particle.

And the reason I like to show this image is… One question that I get is, does PetroFix maybe clog an aquifer or not? And there’s plenty of open-pore space for water to go through and for contaminants to impact and adhere. I should say adsorb to that PetroFix particle. And certainly, I had this graphic out of timing a little bit, but we’re adding the nitrate and sulfate there package so we can get that stimulated anaerobic biodegradation, which then regenerates the carbon sorption sites in a repeating cycle. So technically, you could actually go out in a site that has maybe experienced additional contamination, or if there’s long-term performance that you wanna guarantee, you could go out and just reapply, simple, inexpensive, electron acceptors to keep that regeneration cycle.

So, I wanted to just touch base really quick. You know, what does PetroFix really go after? It is designed specifically for hydrocarbon sites. So the usual suspects BTEX, MTBE, PAHs, things of that nature, as Jack did a great job saying, not really designed for LNAPL. It is not designed for that level of concentration, nor would we be able to target effectively for those high levels. There are some other contaminants that come up that I thought I’d throw on today’s webinar that actually, a couple of these questions came up on the last webinar and they come through every once in a while. So if there’s MTBE there, sometimes people question, can we also treat TBA? I would say that’s a mixed bag with PetroFix. TBA doesn’t absorb very well. It takes a lot of carbon to get a meaningful reduction and you usually need to pair it with something like oxygen to get meaningful biodegradation. So it’s a mixed bag with TBA. We could look at it, but the answer may be no, versus yes.

I would say isopropyl benzene comes up or cumene. Yes, we can definitely treat that. And I also get asked about creosote. When people ask me about creosote or heavy fuels, the way I look at this is that if there are components in that heavy fuel that can dissolve in the case of creosote, we’re talking probably C12 to C28 or C30, you know, you’re gonna have a lot of multi-ring aromatics in there that can go into the groundwater themselves. And certainly, PetroFix is quite effective at adsorbing those, you know, generally quite hydrophobic contaminants and stimulating their biodiver… Excuse me, biodegradation as well.

So moving into some other highlights, you know, Jack covered the three main application approaches that we see 95-plus percent of the time. You know, if you have to go after a source or a plume, whether it’s, you know, it’s treating a well that’s at the back end of a large mechanical system where it’s not performing or whether it’s a very large grid, 20,000 square feet, that, you know, we see the gambit and also excavation of the barriers. In this case, these cartoons are showing direct push, but, you know, PetroFix is very flexible as a technology because it’s non-haz, it’s non-corrosive and it injects like you’re injecting a diluted ink. And so, you know, with direct push that’s probably the most commonly applied approach that you would be considering or we would consider with you. And probably the max step you can go with that is maybe 80 feet. I would say practically, it’s under 50 feet is the working depth range for direct push on most sites.

If you needed to go deeper, you could use injection wells. And that is a question that I would imagine somebody might be thinking here today, is that… You can use injection wells. I would say we would prefer to defer to direct push if you can reach it with a rig, but anything where say it’s in bedrock or deep, you can use wells. And we do actually have application guidelines available to you for that. So we’ve seen some very effective well applications or open borehole applications in the bedrock, by the way. So using packer systems. Certainly spraying the excavations. And one unique sort of innovative application where we actually have a couple of case studies on are tank-based and flooding or excavation flooding, where you’re not able to direct push because of concerns of puncturing a line in the infrastructure, but it’s known that contamination is around and below those tanks from former releases. That is possible. And we’re actually seeing people who have done that.

So, you know, the sky’s the limit. And I would just say the… You know, if you have any questions, just feel free to reach out to us. I wanted to cover something. This is a slide I put in. And the question comes up is where is PetroFix applicable in terms of concentration range, low, medium, or high? I think Jack was really right on earlier saying it’s really effective for low and medium ranges, but maybe we cheat and go to high ranges. You know, I would say that you know, PetroFix has a broad range that we can put in, in terms of pounds per cubic yard. We don’t really have a rule of thumb that we use. But certainly, when we’re looking at a curve, and this is a curve we’ve used for a number of years and I dusted it off, I thought I’d bring it out today where if you look at the general efficiency versus concentration of a technology, the bio-remediation technologies on their own are really good for the low PPV range, but they might start to fall down when you get into, you know, high soil contamination or LNAPL ranges, where you might find that this goal is something that people tend to start looking at. And then certainly, if you’ve got free phase contamination, it’s certainly common to go out and do some sort of a phase extraction system or excavation to get rid of that.

There are overlaps on that curve. But I would say that PetroFix from low to high, it has been encroaching and really has been technically feasible even into some of these mid ranges where you can do or considering chemical oxidation. Now, PetroFix is not gonna treat up heavy salt contamination. It’s not going to treat up free phase. However, if you need to control flux at higher levels, we’ve had clients being able to put in very effective grids or barriers to completely stop that flux over the long term at rates where that flux coming out of, say back to these other types of soils, it’s not exceeding the capacity to absorb or be regenerated.

So one of the things also is that the software that you can use online has what I call a design rail. It will notify you if we think that the concentrations you entered are too high for PetroFix, and we’ll give you a warning to give us a call. And we’d be happy to walk you through that with you. Just a couple of slides left. I want to make a point on carbon. This is something that always comes up when I talk about PetroFix and how does it really compare to other carbon forms? Again, Jack mentioned some of this earlier and really it comes down to size and the ability to inject. So these are images of different forms of activated carbon. The one that we’re really looking at is a powdered activated carbon, which commonly can go down to about 30 micrometers in size. But even at that size, when you put it with water, it needs to be high pressure fracked, usually requiring a couple of hundred PSI versus…

PetroFix, we’re seeing really commonly being below 80 PSI. And so that really helps with control distribution. It helps with minimizing surfacing at the site. These are all things that we’re gonna wanna see being able to get into the flux zones. You can get the PetroFix with this size of carbon, even down injecting and moving through silts that have a porthole diameter of about three to eight micrometers. And this has more ramifications. You know, it’s true that when you frack, there are gaps that are formed and those fracks don’t always go where you think they’re going to go. And when that happens, you know, contaminants can go by, or you might miss hitting that zone, that contaminated flux zone you are going after. It can also be problematic near infrastructure or former excavations where things might go in there. And so you have to be careful about that with say larger forms of carbon in terms of, you know, are you able to effectively cover the entire flux zone? Are the results accurate or do we have to replace the wells? These are considerations that come up frequently for those forms of carbon where this material does overcome that. And the main point I wanna make on this is that PetroFix does go into wells. Would you wanna see it go into wells? It shows us those flexing through the zones we’re adding it to. You can actually remove it from wells with the clearwater flush and the wells are not impacted and they can be rehabilitated. So an important point for you to consider.

All the information you might need to get started would be on our website. Normally, I don’t like to point people to the website and or other technologies, but for this, for PetroFix I do because that’s where our software is. There’s something that’s unique with PetroFix. We are allowing people to do online designs on their own. And I got to say that Antea’s been killing it on there. They’re our number one power user, have many, many designs on there. We’ve been able to interact with them in a lot of great ways talking about sites, design reviews, just back and forth working through putting packages together that they can be successful on.

So instructional videos, other educational content, please do check it out. PetroFix is fully supported. Just because we have online software, doesn’t mean it’s sort of a “go get ’em tiger, leave us alone mentality.” We realize that this can be complicated. We realize that as you get into it, you may not be comfortable with everything and just know that we’re happy to have you reach out for us for online design reviews or general Q&A, offline design support, and even application build support. So Tyler Harris, who is one of our new PetroFix design specialists, or myself, would be happy to help. So hopefully those points that I went through were just a good primer. I know they didn’t cover everything, but hopefully, there are enough to just you know, keep your interest and kind of point you in the right direction on this. And so what I wanna do at this point is why don’t we turn it over some Q&A and thank you for your time on that.

Dane: All right. Thank you very much, Todd. That concludes the formal section of this presentation. So at this point, we’d like to shift into the Q&A portion as Todd mentioned. Before we do this, just a couple of quick reminders. First, you will receive a follow-up email with a brief survey. We really appreciate your feedback. So please take a minute to let us know how we did. Also, right after the webinar, you will receive a link to the recording as soon as it is available. All right. So let’s circle back to the questions here. The first question is a question for Todd. And Todd, the question is if PetroFix is in a well, can you elaborate more on when the monitoring well can be used for sampling?

Todd: That’s a really good question. And I suspected that will come up. So PetroFix as a suspended carbon, it does take time to fully attach to soil. Okay? So it’s not instantaneous… Well, it is instantaneous, but for all of it to fully adhere, it’s not instantaneous. It takes a few weeks to a few months. So what might happen is after you inject it, and let’s say you’re narrow well, let’s say you’re within the theoretical ROI of that well, you could see black water, you know, in that well. Now, a couple of things. I would say that in terms of, you know, PetroFix in a well, you know, one way to look at that is that we wanna see it there because we know that we’re in flux zones. But you can and we often do it when we do our own, when we turnkey PetroFix applications for people, we’ll typically do a clearwater flush at the end of the injection event and push that PetroFix out completely out of the wells and the wall pack into the formation.

Now you’ll still have the coating where it originally coated, but any suspended PetroFix that’s still sitting there gets pushed out into the formation. It’s optional. You don’t have to do it. A lot of people just wait for the PetroFix to fully attach. And that usually takes a few weeks to a few months. We do actually send field test kits out that go out with each shipment that they’re taped to the top of a drum or tote and you can measure that. You do wanna see PetroFix go below a hundred milligrams per liter, which has been verified actually from an outside laboratory to be a treatment range where you can safely sample PetroFix and get reliable results that way. A hundred milligrams per liter is dark. And actually, you can still, if you put it into a 40 mil voa and see through that voa, that’s about a hundred milligrams per liter. But hopefully, that answers the question… Actually, hopefully, that answered the question.

Dane: All right. Thank you, Todd. So here’s another question. This one is for Jack. And Jack, the question is what sites would you avoid with PetroFix?

Jack: I think as Todd just pointed out a moment ago, you know, chlorinated sites, that’s not within the spectrum for PetroFix. I’d stay out of the LNAPAL scenario, obviously. I think that point has been made a couple of times. I think with any technology, with any product that’s out there, you always have to put it in its best light, right? I guess there’s always that concept of pushing the envelope, but that has to be done through careful planning and consideration. I don’t think you’d just go out and do that on your own. So that requires a lot of conversation, but I would say the LNAPAL scenario, chlorinated solvents, you know, that doesn’t seem to work for me. Perhaps some PAAH scenarios, where there’s not a lot of soluble constituents or more volatile constituents, I might be inclined to maybe think twice about that in PetroFix, I guess from my perspective.

Dane: Okay. Thank you, Jack. So let’s see. Here’s another question. This one is for Todd, and it is how long can you store PetroFix?

Todd: Yeah. Interesting, good question. This actually comes up. We do have some people that wanna look at this for say, spill response, things like that, or get stock. I’ve had people ask that who are shipping to Alaska, things like that. So PetroFix is stable for probably around six months. Now we do have recommended guidelines for storage. Don’t allow the material to freeze and try to store it below 95 degrees Fahrenheit. And if you can meet those criteria for that storage, you should be good to go for at least six months.

Dane: All right. Thank you, Todd. So here’s another question. This one is for Jack. Jack, the question is, have you had any regulatory resistance to the nitrate sulfate electron acceptor package for PetroFix?

Jack: Thanks for that question, Dane. Well, the short answer is no with the current package. I can tell you, we fought the sulfate war for years, probably 15 years ago. And you know, perhaps there are even a couple of states to this day that are reluctant to have sulfate injected or put so many restrictions on the ability to inject sulfate that you know, it’s not worthwhile pursuing it as an option on projects. So, I think if you have an ability to explain what’s being done very carefully and the science behind it and the benefits of it, and then have a good solid monitoring plan to really manage the risk associated with the site, that goes a long way to gaining that acceptance. Like I said, we haven’t had nitrate approved in certain states. I know there’s certain other ones that would never even entertain the discussion, but we’ve been able to to get nitrate approved and it had perfectly fine results with it without any significant migration. So it really becomes kind of an education and a risk management process.

Dane: Okay. Thank you, Jack. So let’s see. Here’s another question. This one is for Jack. Jack, the question is, do you do microbial testing on all of your PetroFix sites?

Jack: I’d love to say yes, Dane, to that question, but the honest answer is for certain sites budget can be an issue, but as often as we can, we place a lot of value in being able to do microbial profiling at sites. I consider it essential as far as developing a conceptual site model for any given site. And the more often we do it, the more we appreciate how beneficial it can be, that it really does provide a critical element to understanding a site and be able to manage the site. So in a perfect world, I do it at every single site, PetroFix or anything else, but the reality suggests that sometimes budget catches us. And that’s not something we can make investment in, but ideally, you should do it as often as possible.

Dane: Okay. Thank you, Jack. So here’s another question. This one is for Todd. Todd, the question is, many projects don’t have groundwater issues, but we have unsaturated phase contamination. Does REGENESIS see the use of PetroFix in preventing migration or treating contamination in vadose zones?

Todd: Yeah. Good question. So two things on that. So Jack showed his excavation case study where they applied… They spray-applied PetroFix up and down the vadose zone in an excavation for contamination was there and also as protection as groundwater went up and down. So that’s a really good example that you can… If you can easily apply it and get contact with the PetroFix where the contaminations is at. I do get asked about vadose zone, you know, it comes up, it’s fairly common on that. And generally, the way I like to look at this is that when we inject this material, if we were to inject it into say a sand aquifer, let’s just say, and so it’s percolating downward pretty quickly, there is a resonance time that we need in that aquifer to allow a full attachment of the PetroFix.

And, you know, as I see it, if we were to inject in say sand and it percolates quickly, you’re gonna get an initial partial coating of PetroFix and the rest of the material is gonna go down. And so it’s a challenge to overcome. And then when you get into even more complex environments, it can be really challenging if you don’t have water as a medium to put PetroFix in the vadose zone. And so that’s kind of a double whammy. So I’m a little bearish, I would say, on vadose applications. I don’t usually recommend them. I, I wouldn’t say that we always say now, but it has to be a very specific situation where we know we can get the contact and residence time to get a good outcome.

Dane: All right. Thanks, Todd. So we have another question here. This one is for Jack. And Jack, the question is, have you tried to work outside the parameters of the PetroFix design assistance software and increase the spacing of the points?

Jack: Yeah, I would say to a project now Dane, that we have not. We have chosen to play by the rules. In this particular scenario, I think a lot of the sites that we’re applying PetroFix to right now are sites that have gone through years and years and years of remediation. And we’re really focused on getting an outcome, a desired outcome that gets closure. So we’re trying to stack the deck and really, again, play by the rules, do everything we can to push those sites over the hump. And in many of these cases, like I said, we’re over two dozen sites now with PetroFix. We’re to that last well or two. And if we can get concentrations below standards for those wells, were done. And our client’s a happy camper after 20 years or more. So, yeah, we’re trying to play by the rules and work within the parameters of the design software. And I think that’s paying off. I think we’re up to eight or nine closures now in the sites that we’ve done. So I think that’s a nice track record.

Dane: All right. That’s that’s great. Thank you, Jack. So here’s another question and this one is for Todd, and it is can PetroFix change the flow direction of an aquifer?

Todd: No. We don’t expect to see that. The technology is designed to coat and take up a very small percentage of the pore space. It doesn’t have a particle size that tends to occlude the transmission zone. So, you know, we haven’t seen that at all, actually for PlumeStop or PetroFix. That does come into play with one of the techniques that we employ such as barriers. Like we don’t want to be diverting water around a barrier. We want it to flow through. So because we’re not occluding or clogging aquifer, we’re able to do very effective raise and I guess barriers. In fact, I don’t remember the largest one, but it might’ve been as high as 800 feet that we’ve done for PetroFix barrier. I think that was in Europe. So, no. It shouldn’t be a problem. It’s not gonna be a problem.

Dane: All right. Thank you very much, Todd. So that is going to be the end of our chat questions. If we did not get to your question, someone will make an effort to follow up with you. If you would like to learn more about Antea Group, you can visit anteagroup.com. If you’d like to learn more about remediation solutions from REGENESIS, please visit regenesis.com. Thanks again very much to Jack Sheldon and Todd Herrington, and thanks to everyone who could join us, have a great day.