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, 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 will collect your questions and do our best to answer them at the end of the presentation. If we do not address your question, 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 webinar will provide an overview of AquaFix, the first ever solid micron scale electron donor to treat chlorinated solvents.

With that, I’d like to introduce our presenter for today. We’re pleased to have with us Dr. Paul Erickson. Dr. Erickson is the Director of Research and Development with Regenesis, overseeing the commercialization of new environmental solutions to address complex remediation challenges. In his time with Regenesis, Dr. Erickson led the development of a number of remediation products and technologies, including PetroFix, FluxTracer, and AquiFix. Dr. Erickson earned a BS degree in chemistry from Florida State University, a master’s in chemistry from the University of Minnesota, and a PhD in environmental chemistry from ETH Zurich. He’s an author on over 20 peer-reviewed scientific publications, mainly in the area of environmental chemistry.

All right. That concludes our introduction. So now I will hand things over to Paul Erickson to get us started.

Thank you, Dane. And hello, everyone. It’s a pleasure to be with you today to give you an update and an introduction into the product that we’ve been working on for quite some time, Aquifix. And as Dane mentioned, this is the first solid colloidal electron donor available. And so happy to be here, and let’s get into the presentation.

So first, a quick overview. So given that this is a new electron donor, what I’d like to do is start by giving a quick overview of the concepts of enhanced reductive dichlorination, kind of walk through the necessary nuts and bolts of how that works. And then I’ll spend a little bit of time just as a setup talking about plume stop and how we couple that with enhanced reductive de-coronation, why that’s something that we wanna do and the developments that we’ve undertaken to improve that process. And with that, we’ll get into the specifics about Aquifix, what it is, what’s unique about it and how we see it being used. And then after talking a little bit about some of the lab data, proof of concept work that we’ve done in the course of developing the new product, we’ll get into a field demonstration that was ongoing for a number of years that really help set the stage for using the product moving forward. And after that, I’d be happy to take some questions and get some answers.

So let’s jump in. So enhanced reductive dichlorination, or really just reductive dichlorination, is the process by which halogenated contaminants, oftentimes we see PCETC, these chlorinated ethines, as the poster child compounds for this process. And when we say enhanced, we’re adding something, we’re doing something to speed up or enhance this process. But at the core, whether it’s something that we’re enhancing or just naturally happening, it’s driven by the presence of microbes that are able to facilitate this dichlorination reaction. So there’s microorganisms that respire onto these halogenated substances, and what they need is a hydrogen source. So they’re using, they need some food. In this case, they use hydrogen and that’s produced by fermenters that are present. And really there’s any number of carbon sources, fermentable carbon sources that are capable of producing this hydrogen. And once it’s around and you’ve got the right microorganisms present in order for this to happen, then they’ll take this hydrogen and just sequentially knock off chlorine. They’ll sequentially knock off a chlorine and add hydrogen, and listed here, you can see that there are a number of species that are capable of undertaking this first step, you know, these early steps of the higher chlorinated contaminants. But the slowdown, the bottleneck can often happen where you get down to cis-DCE and beyond. And that’s, we know that dihalicocoides is one of the few, if not the only, that we know of group of organisms that’s capable of doing this.

There are other pathways, co-metabolic pathways that can bring these contaminants on through, but no matter what, you’re oftentimes trying to get your heavier halogenated compounds down to ethene, which then is easily degraded and not really of concern. So that’s the concept of enhanced reductive dichlorination that we’re going to be talking a lot about today. Hand in hand with that is the idea that we can use injectable carbon sources, injectable activated carbons to enhance the remediation process. So here at Regenesis, we have a technology known as Plume Stop. And Plume Stop is a colloidal activated carbon that is injected into the subsurface. This gives you a platform on which your contaminants that are moving in with groundwater can adsorb out of solution. And what’s nice about Plume Stop is you get this rapid absorption of your contaminants. So you get immediate reductions in your groundwater concentrations within an area that you’ve treated with plume stop. And then as more mass continues to flux in, this is managed within the same area. And so you get rapid drop in concentrations, flux management.

When it’s coupled with biodegradation, which we’re gonna talk about today, you don’t often see, or you see very minimal daughter products start to show up in the dissolve phase. So you see minimal, in some cases, no CVOC daughter products that are being formed within this area of treatment. And as mentioned earlier, what we’re trying to achieve here is biodegradation of these contaminants with the sorptive barrier, where you’re sort of slowing everything down. You can do this within a smaller footprint when you use an activated carbon-based amendment like Plum Stop to help out your treatment scenario. And really what this does is if you can couple bioremediation, biodegradation of your CVOCs with Plum Stop in this smaller footprint, then you’ve got a long-term efficient system to treat your chlorinated solvents. And so this wheel you see here kind of outlines the process that with activated carbon with PlumeStop, you get contaminant absorption. You can support biofilm growth and just robust bioprocesses that are happening within this area. Your degradation then helps keep the absorption sites free. And then that allows for more contaminants to come in, flux in, to be remediated. And so this is the concept that we’re trying to go after when we’re remediating chlorinated solvents with Plum Stop and using biodegradation as a part of that process. And so there’s a number of amendments, these hydrogen sources.

So remember we said we need something, some fermentable carbon source, not activated carbon, but some fermentable carbon source to generate the hydrogen that’s gonna support these microbes. And so I’ve got listed here a table that kind of walks through the different options that are on the market or available to practitioners. And generally, they’re separated in terms of longevity is one way to think about it. So going from water-soluble type materials down to solids that do have quite a lot of longevity. But let’s look at the different categories we’ve got here. So in addition to the longevity, you’ve got application method, how easy something is to distribute, And then important to the concept that we’re outlining today is the compatibility with an activated carbon based treatment. And so what you see is that for soluble amendments, you’ve got ease of application is quite good. The distribution, given that they’re water soluble, is also favorable, but they don’t last very long. So when you’re using something like a lactate or a molasses, you have to come back and reapply on a regular basis. You know, given the water solubility, they are compatible with activated carbon. There’s not really a competition for sorption sites, which is the concern in terms of compatibility with something like Plum Stop. But you’re going to have to come back and reapply, you know, for perhaps every three months with options like this.

You know, emulsified oils, EVOs, they do have, they share the properties of being fairly easy to apply and fairly good distribution as well. The persistence is also better, but the issue is that with these types of amendments, EVOs, you’ll get blinding of your activated carbon. And so what that does is you’re blocking the sorption sites for an amendment like Plum Stop, and then that causes problems with this flux management that a product like Plum Stop is able to give you. Solids, again, great longevity for something like this. You really can get long-term barriers built, but they suffer from being difficult to apply. So they are oftentimes fractured in for a lot of these types of materials. The distribution, just given that they’re not in a form that easily moves through porous media, is not that great. And in theory, someone could use something like this up gradient of an activated carbon barrier. But the issue with that is that now you have more complex projects when you try to implement these. So in order to try and streamline this process, we’ve developed this material Aquifix, which is it is itself a colloidal solid.

So the long-term component of the donor is something that is in a very small form. I’ll touch a little bit more on what it looks like. But you can apply this material under low pressure and its distribution is very similar to plume stop. So what that means is that it can be co-injected. So this material is something that can just be mixed right in on site and applied with plume stop. And the target was to make it compatible with activated carbon. So that also ticks that box as well. So Aquafix is the name of this material, name of this product that we’ve developed. And as I mentioned before, it’s a solid colloidal substance. So the particle size on the long-term releasing component of it are quite small. They’re on the half micron scale and it’s an organic substance, fermentable organic carbon. And along with the small colloidal organic substrate, there’s also blended in fast release components that will help perform that ERD necessity, which is to drop your oxidation reduction potential within the area down to where you need it to be and prime the site, the conditions for strong bioremediation along in the formula is also some micronutrients.

So there’s components that contain things like B12, things that we know through experience that are important to make sure you have on your site for good robust bioremediation to occur. And again, the solid component that’s present in the product is capable of releasing TOC for in excess of 10 years. And we’ll get into some of the data that we’ve collected from the lab and the field to help tell us about the validity of this claim. So really, the key innovation is that we set out to develop a new electron donor that is compatible with Plum Stop in terms of not interfering with absorption, but also the longevity of a product like Plum Stop. And so that’s what we’re going to talk about today and get into the real data that we’ve collected on this material. So first, I’ll outline just what I’d like to call proof of concept studies that we’ve done in the lab, just to demonstrate in a bottle that this material works and how did we assess performance and longevity will be the next set of data that we look at.

But first, just a simple microcosm study that we did. And so if you take the products and you put it into, just close microcosm bottles, will it dechlorinate or can it support dichlorination by culture? And so we dosed in our Aquafix along with a spike of our BDI +, so we bio-augmented these cultures, these samples as well, with dehalococcoides containing a culture. And then at different time points, we spiked in TCE. So basically, can you get dechlorination? And then does that process continue if you continue to add contaminants with time? So a quick look at the data. And so what you see is that we do get dechlorination. So the purple line that continues to go up, that’s just our abiotic control. So a set of bottles that got continued spikes of TCE. But evident early on here in the early data points is that our TCE, which is in green, we get dechlorination. And you can see that you do see some daughter products forms, and with time, the bottles sort of acclimate. And eventually, you’ve got a system that’s quite capable of dechlorinating and active at the three-month time point.

For a product like this that’s got quite a lot of longevity, these short-term microcosm studies can only tell you so much. But what they can tell you is that you’re really supporting and you’re seeing the behavior that we looked at before and that really one expect is that starting from something like TCE, you get this turnover through your daughter product chain onto cis-DCE. Finally, you get some vinyl chloride, and then with time, all of this is removed, and you’ve gotten full dechlorination going through that pathway that we looked at at the very beginning that’s sort of that classic expectation for bioremediation of chlorinated solvents. So speaking about the longevity, we have it in that this material can last for quite some time. That comes from what the material is, and then also some performance data that we have from the lab. And that’s what this dataset will kind of walk you through. So what we did is we put into just thousand milliliter jars that were filled with 900 milliliters of solution. We added to those 20 grams of our organic substrate in each of the cases you can see here. And they were also spiked with BDI. Really, this was just to a culture of bacteria that would then be, you know, BDI has D. helicochoides, but there’s also present in the consortium, bacteria that are capable of fermenting organic substrates as well.

You know, it’s not a single species, but rather a consortium. And so to this mixture, we would remove every two weeks, 10% of the volume for analysis, but also to sort of simulate a flushing of the system, one that one might expect in the groundwater. and then the samples that were removed were taken for TOC analysis. And really what we’re trying to observe or demonstrate is the longevity of TOC in the different cases. And so what we see here is that for something like a sodium lactate, all of your organic carbon is found in the aqueous phase right out of the gate. And so what you see is the steady decline, this rapid decline in in aqueous phase TOC as we get this flushing, as you get utilization of that carbon, and then if you look at this oil lactate, which is kind of a generic form of many of the products that are on the market today, so your oil lactate, EBO-type mixtures.

As mentioned before, the longevity is pretty good, but then now you also have this orange line that’s skirting along the bottom, and that’s the solid component that’s in AquiFix. And so one point I forgot to mention is that early points in this analysis, in the early we also were collecting for all of these data points or all these trials of volatile fatty acids just to assess Are you seeing the acetate that you expect? Are you getting some pyruvate? These are the kind of indicators that the conditions are primed for enhanced reductive decombrination. But let’s zoom in down to that orange line And what you can see is that deep below what you were seeing for these other materials is you have this slow steady? contribution of TOC, you know, we are seeing aqueous TOC being formed from the aquifix solid at very low levels that would then be able to be sustained for quite some time. And so if you look down at the bottles in all of the cases, which this is a photo of one of the actual bottles from the lab study, you could kind of jostle the bottle and see little air bubbles, presumably CO2 and methane bubbles coming up from the mixture of the soils and the amendments themselves. And so, really, this was good evidence that there’s strong bio.

We’re seeing TOC being generated from this and other materials. But really, the longevity that we’re after, as long as the dosing is right, that we should have TOC release from a material like this for a significant period of time. And that was the objective. So with that, I’ll transition over to the field site. So after we had a product in mind that we could commercialize and bring to the production scale, we brought it to the field for some initial testing. And so at this point, we’re fortunate enough to already have two full years of data on the performance of this site. And so the location that we chose to work with Aquifix from the beginning was a chemical manufacturing and distribution facility in Michigan and history of manufacturing and distribution of chlorinated solvents as well as hydrocarbons. And so it’s quite a large plume coming off of the site, high concentrations of both CVOCs. There’s also 111 TCA present on the site as well. And of note is that it’s co-mingled with L-NAPL in some portions of it. And so there are areas that already have high concentrations of cyst ECE and other daughter products present.

There’s also quite interesting geology in this area. So the plume takes this abrupt turn to the south, and that’s largely due to an esker. And what that is kind of as glaciers retreated, it left this gravel, sandy trench that’s got quite high permeability and really responsible for this area where you can get quite high mass flux and groundwater velocity moving through the area. And so for this study, we picked two different areas, two treatment areas shown here that we’ll talk about today. And so the objectives of this campaign, this initial beta campaign for using Aquifix, were kind of twofold. One was to demonstrate Aquifix’s ability to maintain favorable ERD conditions. So with such a slow release profile, we need to make sure that we’ve got the dose dialed in right so that we get enough release to keep the ERD conditions where we need them to be and keep those under favorable conditions. And then also, you know, equally important is that we can demonstrate the compatibility with plume stop, that we can get this adsorption of our contaminants, support bio, and identify that that’s a process that’s going on in these locations.

And so what we did is, for these two different areas, we decided to apply one area that had AquiFix by itself, and then one where we used AquiFix together with plume stop and treat them separately. So kind of two different areas that we can ask two different questions and as best as possible control variables from site to site. So the criteria that we used to evaluate the performance on this site was listed here. So our classic performance metrics, so the CVOCs, are we reducing the concentrations of the contaminants of concern that we’re after? Also important for bio and ERD performance are dissolved gases. So we collected methane as well as ethane ethene data. And again, this helps us understand, are we getting complete mineralization in the form of ethene? So remember back to our first slide that the final product of our CBOC degradation is formation of ethene, we’d like to see that. And then bio, ethene is gonna be produced biogenically as well as methane. And are we getting release of the donor to the rate that we need it to?

So following TOC was an important parameter for both of these treatment areas. And then just to gather data on, is this product supporting bio the way that we expect it to, we did quite a lot of sampling for microbial populations, so via QPCR. So are the right microbes present? And are they present in the appropriate numbers that one would need to expect strong bioremediation on our site? So I’ll walk through now the two different areas a little bit more in depth here. And so the first is the area that we did just aqua-fixed by itself. And so, you know, in both cases, we made kind of these permeable reactive barriers just up gradient of the monitoring wells that we were working on. And so we know that there’s kind of a continuous feed of contaminants as the groundwater moves kind of from the northwest to the southeast. And so barriers were roughly 20 feet long, and we injected over about a 10-foot interval. And you can see here the product amendments that were chosen. And so again, this area was just Aquifix by itself.

As you’ll see in the data, the Aquifix alone was, this area was chosen because it was still toxic. So there wasn’t really much influence from prior remedial actions that have been done or the commingled hydrocarbons that were present. So what we had was really just straight parents in this case. And this is an excellent test case to see, are we able to establish and maintain good ERD conditions with AquiFix. So that was really the primary goal of understanding that in this location. Aquifix during the work. And so what you can see here is we’re set up already with temporary wells on this PZ1 and 2 as we pump into injection point two. So again, given that this is an R &D project, we’re fortunate enough to have the time to slow down and do a little bit deeper dive on the data that we’re collecting and trying to understand really what’s going on in the field when we’re doing these applications.

So the area that we did a combo, a Aquifix Plume Stop application was a little bit north of this area. And in this case, there was quite a bit of daughter products already present. And you’ll see that when we get to the results. But again, same amount of Aquifix, but this time we applied Plume Stop and a very similar configuration is the area that just had Aquifix alone. All right, so let’s get into the data. So what you can see here, this is the well that we just did Aquifix by itself, so it’s SPMW-12. And as I mentioned before, this area was a good choice for doing ERD, just Aquifix alone, because it had only parents’ product present in the beginning. So there was TCE, I think you’ll see in a graph just after this one, a little bit of PCE as well. But what we saw was that really after the third month, we had kicked off biodegradation, so ERD was starting to take hold because we could see that all of our parent had been converted onto cyst ECE, and that with time, we saw this classic behavior that we’ve seen now a couple of times in this presentation where your parents get transformed into daughters, in this case, cysts, you start to see vinyl, and then that end product that we want to see, ethane, starts to show up as we go on with time.

And so looking over the two-year period that this study was going on, you know, we’ve nearly eliminated all the contamination using AquaFix by itself. And so that’s what we’re hoping to see. And the question about, do we get enough TOC? Are we getting that TOC profile that we want to see to also support good ERD? you can see that in these black squares here. So pre-application, we had fairly low, this is a log plot for our TOC here on the right. And you can see in the beginning, there was quite low TOC present. After application, that’s the fast release components that we see from AquiFix. And then after about the 12 month mark, we’ve really settled into this slow steady release of TOC that we expect with a material like this. And so this is what we were hoping to see and what we’ve got in the data. So if we look at the chemical data instead of just on a mass basis but we switch for a moment and talk about molar concentrations and molar fractions, this is the same data just plotted in that way. And so what we see again is in the beginning on this SBMW-12 we really only had parents.

So there was TCE and as I mentioned just a little bit of PCE but really by our first monitoring points we had converted pretty much everything into daughter products and then that just has built with time. And so these later time points, we had somewhat of an anomalous big peak in ethene. Not sure why it was so large, a good sign nonetheless, but it’s fallen off and really we’re starting to reach our analytical limits down at this low concentration for ethene. But all signs point to there’s still robust bio. And remember, there’s still mass that’s fluxing into this area from upgrading. And so we’ve really seemed to have established a strong area using AquiFix where we’re getting good turnover of the influxing CVOCs, good bioremediation of them, and onto lower daughter products or end products that we want like ethene. And so that also is evident in this black line, the fact that there’s still mass fluxing in. In the beginning, we had our total molar concentration was sitting here at 10 to the three nanomoles per liter, and that’s roughly the same. And it’s started to drop here, which again is a good sign, but the point being we’ve got good mass balance across the site.

So last point of data for this area is our microbial data we mentioned. And so by collecting the, we’re looking for gene copies of Dehelicochoides as well as the final chloride reductase gene. And both of which you want to see on a site that that’s good evidence that you’ve got which is that final microbe that’s capable of turning over cysts on to vinyl and then ethene. And what you can see is that we’ve got, you know, strong populations all the way at the two-year mark. So the rule of thumb number is 10 to the 4 cells per mil. If you’ve got about 10 to the 4 cells per mil or above, then you know the going wisdom is that that’s a robust enough population of Dehelicocoyotes to support strong bioremediation. And so within this area, SPMW-12, we have all the signs of a positive ERD project at play here. So now we’ll switch to one of the two wells that was present on the PZ-20 at 73. And we’re looking at the deep well. So I won’t talk about the shallow well today.

Performance was also quite good. There was a little bit of differences in performance between the two, but generally they behave the same, you know, 90 plus percent reductions in all CVOCs. but just for clarity today, we’ll focus in on the deep section. And as I mentioned, there had been prior remedial actions as well as just influence from the co-mingled plume, which had some hydrocarbons that were able to push productive dichlorination as well. So before we even started work, there was, in addition to TCE, quite a bit of cis-DCE. And what you can see is after our plume stop application and AquiFix, you, again, you see immediate reductions in your groundwater concentrations, which were quite high for both TCE and your cis-DCE. So you get this rapid drop. And then over the two-year course that we followed the data, we see that our CVOCs never rebound, but rather by that 10–12-month mark, we’re starting to see strong formation of ethene.

So really, this is exactly what one wants to see on a project like this, is that your solvents and daughter products have all been eliminated by your treatment area, and then you’re pouring out the byproduct that you want to see, which is ethane in this case. So on TOC, you can see again that in the first 12 months, you’ve got what’s showing up here is your fast release component. So that’s hanging around, and then it’s exhausted by about 12 months. And then you get this plateau of the slow release that we expect, again, to go on for some time and continue to support the bioprocesses that we’re observing here. So again, switching to a molar basis to look at our data, you know, you could see again, this just better highlights just how much CYS-DCE was present in the first. So only 25% of the contaminants were just our parent, in this case, TCE at the beginning.

But again, after application, we’ve all but eliminated our TCE and our CYS starts to then with time, on a molar basis, get pushed off and replaced by ethene. So we are getting conversion from our starting material, which is our, in this case, cis and TCE, and we’re generating ethene, which is a sign that we’re getting full dichlorination. We’ve got strong bio and good bioremediation happening within this treatment area. Again on the molar basis, we started at 10 to the 5 nanomoles per liter, and we’re approaching that again, and this time really just in the form of ethene. So this is showing you that you’re getting good turnover, you’ve got good mass balance within this plume stop treated area. That’s another good sign that in addition to this adsorption process that you get from plume stop, we’re supporting and stimulating bioremediation to get full destruction of the material, the contaminants as they flux into this treated zone. And, again, as in the case of SPMW-12, we’ve got great populations of our dechlorinating bacteria.

So, the helicocortis, again, is well above that mark that you at least want to see it at the 10 to the 4. So, we’re over an order of magnitude, and plenty of final chloride reductase gene present as well. So, this is everything that we want to see in a project like this. And last bit of data that I’ll share before I wrap up with the conclusions is that microbial Concise is now offering a metabolic, let’s call it a meta-array, is the name of this new procedure that they’re offering. And it’s a metabolomics approach that allows you to go and look well down the, let’s call it the ladder of activity in terms of biological processes. You can, using meta-array, gather information about, are the small molecules, are the day-to-day molecules as we like to call them, that these dechlorinators need and make and just are the fingerprints, if you will, of their presence, are they there? And can you find enough of them to say that you are in a condition that supports high reductive dichlorination potential?

And so just one more time, what we were looking at before was all genomics-based information. So when you’re looking at the DNA, that’s telling you that these microbes, at least their fingerprint of their presence is there. And so that’s a good sign you want to see it. But as you get farther down the chain here of activity, and you get to metabolomics, this is really a sign that not only were these bacteria there, but they’re there very recently, because they’re small molecules which are not very stable, don’t hang around very long. They’re still present in concentrations that you want to see. And so that’s what the data that we just got in from Microbial Insights helps to show us, is that within each of these three areas, the wells that we were sampling, the ones that I talked about today, this SPMW-12, was the one that just got a treatment of Aquafix. And then the rest of the data we talked about was the PZ2073D.

But they’re falling in this category that shows, yes, you’ve got all the signs from a metabolomic standpoint of high potential for reductive dichlorination. So again, just another positive line of evidence that we’re seeing what we wanna see after a treatment like this, we’ve got strong bio, and we’ve got the conditions where we want them and we expect them to stay this way. This data set was collected after two years. So we expect it to continue down the road as well. And so to conclude, to wrap up, what we talked about today was this is our new ERD supporting product, so Aquifix. And it does just that. It’s able to support robust CVOC bioremediation. And given the slow release of this TOC source and compatibility with activated carbon, you’re able to create these long-term sustained TOC releases that are compatible with PlumeStop and allow one to construct a passive system that will operate for a very long period of time.

So really, this is an excellent cutoff system when deployed together with PlumeStop. And the biogeochemical data support that we’re seeing what we want to see, robust bio, and the release profile is consistent with the expectation that we could have performance in these sites for, you know, 10 plus years with a treatment of this type. And so with that, I’d like to, as I wrap up, give some acknowledgments. So the data that I showed for the beta site would not have been possible without Joel Parker and Abigail Arner with Hampton Matthews. So this is one of their sites in Michigan. They were great on getting us onto the site. And then the follow-on collection of data, reliable, just pleasure to work with and really able to help us collect this robust data set. So they were the ones out there collecting the data and working with us to bring this all together. I’d also like to thank Sophia and John here internally at Regenesis. The lab data that you saw all came from Sophia. And on the commercialization side of things, we all work closely together with John on this and really is what was able to bring this product from concept to commercialization.

So with that, I’d like to thank you all for listening and I’d be happy to take some questions.

All right, thank you very much, Paul. That concludes the formal section of our presentation.