1 00:00:00,296 --> 00:00:01,349 FRTR Presenter: The 1st 2 00:00:01,740 --> 00:00:12,123 FRTR Presenter: talk for today is titled source differentiation concept, pfas, source differentiation guide for airports, and our speakers are 3 00:00:12,960 --> 00:00:24,789 FRTR Presenter: Well, Dr. Janet Anderson. Janet has an Abt. Is a Abt certified toxicologist and a vice President principal toxicologist at Gsi Environmental. 4 00:00:24,990 --> 00:00:30,589 FRTR Presenter: she completed graduate work at University of Cincinnati post-grad work at the EPA. 5 00:00:30,690 --> 00:00:32,850 FRTR Presenter: Before coming to the Air Force. 6 00:00:33,110 --> 00:00:45,680 FRTR Presenter: where she spent, I believe, about 5 years, I guess, at afcac she focused on strategies for addressing unregulated chemicals, including pfas 7 00:00:46,248 --> 00:01:01,069 FRTR Presenter: and since joining the consulting sector in 2015, she has specialized in chemical risk management, public policy, analysis, compliance, improving corporate environmental and public health stewardship. 8 00:01:01,560 --> 00:01:15,920 FRTR Presenter: She advises stakeholders on issues related to emerging chemicals, such as Pfos. 1, 4 Dioxane microplastics as well as legacy chemicals, such as metals and pesticides. 9 00:01:16,410 --> 00:01:24,869 FRTR Presenter: And so today she's going to be joined by Zachary Poochez, who is an Air Force planner at Meade and Hunt. 10 00:01:25,270 --> 00:01:40,263 FRTR Presenter: He has combined 22 years of airport management and aviation consulting experience, so he has operated on both sides of the coin, if you will, I think, brings a great deal of practical expertise there. 11 00:01:40,800 --> 00:01:52,247 FRTR Presenter: After earning a degree in aviation science administration from Western Michigan University Zachary became an airport operators. Coordinator at 12 00:01:53,330 --> 00:01:58,120 FRTR Presenter: to to I can't even say it, can I? At at 13 00:01:58,560 --> 00:02:08,849 FRTR Presenter: Tedterboro. Is that right? Tedterboro airport? I'm not sure where that is, he can perhaps tell us. And later, as airport Operations officer at the airport in Lansing, Michigan. 14 00:02:08,890 --> 00:02:11,581 FRTR Presenter: he's a key contributor to 15 00:02:12,340 --> 00:02:13,772 FRTR Presenter: a couple of 16 00:02:14,310 --> 00:02:30,159 FRTR Presenter: recent reports. Acrp, report, 173 use of potential impacts of a triple F contaminated pfas at airports and report 255, which is pfas source differentiation guide for airports. 17 00:02:30,470 --> 00:02:43,989 FRTR Presenter: Since publication. Of these reports he continues to assist airports, nationwide, and strategies to address pfas and transitions to fluorine free phones. And so, without further ado, 18 00:02:44,590 --> 00:02:45,930 FRTR Presenter: Dr. Anderson. 19 00:02:48,600 --> 00:02:51,070 Janet Anderson, GSI: Thanks, Kent. Good morning, everybody. 20 00:02:51,660 --> 00:03:03,719 Janet Anderson, GSI: Thank you all for having me and Zach here today. We're going to talk about our work related to the Acrp or the Airport Cooperative research program project on source differentiation. 21 00:03:04,111 --> 00:03:23,639 Janet Anderson, GSI: Why is this important? And why, you know, did were we funded for that? Well, as really well said by Rep. Earlier. Zach and I both work in the space of really helping our clients make tangible decisions, using the state of the science, but walking them through from the very, very 1st 22 00:03:23,750 --> 00:03:24,840 Janet Anderson, GSI: sort of 23 00:03:24,860 --> 00:03:41,550 Janet Anderson, GSI: panic moment of you have pfas, or you have to identify or investigate pfas all the way through to helping them design effective mitigation strategies and remediation strategies. And so we came together to work on this project. And, Zach, maybe if you go to the next slide, please? 24 00:03:42,160 --> 00:04:00,030 Janet Anderson, GSI: Yeah. So we were funded by the airport cooperative research program and to do this work to issue just basic guidance for report managers and the similarities obviously are a triple F releases and working through conceptually how to go from start to finish. 25 00:04:00,030 --> 00:04:19,789 Janet Anderson, GSI: And what does that mean for site characterization, as Rip said earlier, having good site, characterization, and really understanding the landscape literally and figuratively, of your release locations is just imperative to then future decision making, including doing risk assessments and designing effective, risk-based management. 26 00:04:20,256 --> 00:04:32,869 Janet Anderson, GSI: So if you want more details of the report, this is the citation report 255. It's available on the transportation Research Board, Acrp website. Next slide, Zach. 27 00:04:32,940 --> 00:04:43,749 Janet Anderson, GSI: we would be remiss if we didn't talk about our other team leads on the project. So the Dan Schneider, with Terracon and Matt, really were the 28 00:04:43,750 --> 00:05:04,189 Janet Anderson, GSI: sort of the glue that help the program together, and our project together, and the 4 of us led this work, and then next slide. But we weren't alone. We had a lot of really great support on this, and in fact, some of the future. Your next speaker, Kavita and Patel, was part of our team. We also worked with your friends and use their data. 29 00:05:04,360 --> 00:05:27,270 Janet Anderson, GSI: And so it was a really great collaborative effort between the folks listed here and again. The overall goal of our work was to take this, what can sometimes seem very complicated? And when people think about source identification or forensics jumping to really sophisticated and rapidly evolving great science. 30 00:05:27,320 --> 00:05:33,210 Janet Anderson, GSI: but distilling it down to the decision, making process behind it. What can you do? And when can you do it? 31 00:05:33,575 --> 00:05:39,949 Janet Anderson, GSI: And so, maybe before we jump into the research, Zach, do you wanna next slide? Just give a little bit of background on the Acrp program. 32 00:05:40,380 --> 00:05:58,049 Zachary Puchacz (Mead & Hunt): Yes, absolutely. Good morning, everybody. Thanks for letting us be a part of your session here this morning, and as someone who's done a number of airport cooperative research program reports. I'd be submissive if I didn't at least put a plug for them. So it's an industry peer, an industry peer driven 33 00:05:58,050 --> 00:06:21,790 Zachary Puchacz (Mead & Hunt): approach to research. Maybe some of you in the audience and attending online have participated in a panel or submitted a project or an idea for other transportation Research board projects. But the reason why I wanted to bring it up is that you don't necessarily have to have an aviation background to be a part of it, I know in our project we had a representative academia be on our project panel. So 34 00:06:21,790 --> 00:06:33,339 Zachary Puchacz (Mead & Hunt): if it's something you're interested in pursuing, have some expertise you'd like to contribute. Think about joining this and how this program works is that once a year it takes submissions for research ideas 35 00:06:33,340 --> 00:06:58,059 Zachary Puchacz (Mead & Hunt): from those out there from really anybody can submit an idea, and those ideas are then vetted through a panel within Acrp and the Transportation Research Board, and then usually around the early part of the year. I'll call it maybe late winter spring. There's usually a there's an announcement of the projects and opportunity to bid on those, and I might have my timeline there mixed up, because I think it's actually earlier than that. But anyway, please look into it. 36 00:06:58,060 --> 00:07:06,710 Zachary Puchacz (Mead & Hunt): If you have the website on there. That's how you can find our research report to go to that link and do a quick search for Acrp report 255. You'll be able to find that. 37 00:07:06,910 --> 00:07:09,980 Zachary Puchacz (Mead & Hunt): So, Janet, I will turn it back over to you. 38 00:07:10,130 --> 00:07:11,010 Janet Anderson, GSI: Great. 39 00:07:11,190 --> 00:07:28,949 Janet Anderson, GSI: All right. So, as I said, the research goal was to develop some practical guidance. We really wanted to hand to the world of practitioners, a simplified and decision logic that doesn't just take, you know, high level and and 40 00:07:28,950 --> 00:07:53,529 Janet Anderson, GSI: technical report that requires a consultant to understand, but really trying to target those remedial project managers who are faced with the challenge of When do you hire the high level consultant? When do you bring in the fancy models that we'll hear from our next speaker. How do you walk through this process? What can you do from a start to finish? Kind of evaluation, and what kind of lines of evidence do you need to pull together? 41 00:07:53,760 --> 00:08:00,029 Janet Anderson, GSI: So that was the overall goal of our research? The why, though next slide, Zach, please. 42 00:08:00,450 --> 00:08:14,509 Janet Anderson, GSI: So, as we all know in this room. But I like to simplify things. To start from. Pfas may be an environment for several different reasons. We have the primary manufacturers. That's what I call the feedstock. Those are the the makers of 4 chemicals. In the 1st place. 43 00:08:14,550 --> 00:08:41,450 Janet Anderson, GSI: we also then have their clients, the people that they sell the feedstock to. Those are the secondary manufacturers. Those are the people that make the triple F, or that make the Teplon tape, or that coat the wires, or whatever they do. And then we have the product users, those that use the products that contain the pfas, and then some of those like a may result in environmental release. All of those have waste streams. 44 00:08:41,450 --> 00:08:58,429 Janet Anderson, GSI: and next slide Zach, or next click, and all of them, unfortunately, may also have environmental releases. So all of that together means that we really have the potential for multiple potential sources in any given location. And that means that our conceptual site models can be pretty complicated. 45 00:08:58,783 --> 00:09:13,640 Janet Anderson, GSI: We know that under circular we have to consider background background, right? We know pfas are anthropogenic. So how does that all fit into the story of trying to understand a site that may be impacted by multiple different sources, whether it's 46 00:09:13,980 --> 00:09:21,270 Janet Anderson, GSI: pfas in the rain or actual other sources that contribute significant mass to the environment 47 00:09:21,360 --> 00:09:22,959 Janet Anderson, GSI: next slide, please. 48 00:09:23,440 --> 00:09:31,099 Janet Anderson, GSI: So, Zach, you have all the expertise on our team on actual airport work. So maybe you can talk through the pfas landscape that we had considered. 49 00:09:31,100 --> 00:10:00,970 Zachary Puchacz (Mead & Hunt): Absolutely so. That was one of my roles on this project with me, having an airport operations and being an airport firefighter early in my career of kind of bringing those operational considerations. So for those not familiar with the Pfas situation at the airport, I'm sure you've heard about it in the firefighting film. And that's obviously the most significant source. And a lot of that has to do with the direct pathway it has to the environment. And then the volume of it that's used in an emergency. But what's important for airports to understand is that it's not 50 00:10:00,970 --> 00:10:10,219 Zachary Puchacz (Mead & Hunt): wasn't necessarily only used in emergencies. So prior until a few years ago there was a requirement for airports to actually discharge the phone from the fire trucks 51 00:10:10,220 --> 00:10:31,009 Zachary Puchacz (Mead & Hunt): once a year as a part of their calibration of the phone system. So even that small amount of discharge you have that potential for concern of entering into the groundwater. Some airports had firefighting training facilities on their airport. I know that that's not common for every airport, but some had those. Some may have trained with it, even though they didn't have 52 00:10:31,010 --> 00:10:34,330 Zachary Puchacz (Mead & Hunt): the physical facility, I'll call it. And 53 00:10:34,330 --> 00:10:58,639 Zachary Puchacz (Mead & Hunt): there's those accidental releases. Right? You're doing maintenance. A firefighter accidentally hit the button on the truck. Those types of things happens and occur. But there's also other accidental discharges of foam, and Janet will talk a little bit more about other sources of pfas at an airport, but some hangar releases. I'm sure you may have seen videos on Youtube where you'll see a hangar fully engulfed in foam because a fire alarm switch went off. 54 00:10:58,640 --> 00:11:12,749 Zachary Puchacz (Mead & Hunt): So those are the the primary concerns for pfas at an airport. Janet will talk about some other ones, and why our research report really focused on the types of pfas found in the firefighting foam versus other types of pfas found at an airport. 55 00:11:15,780 --> 00:11:41,369 Janet Anderson, GSI: So I really doubt I have to go into much detail on a triple F at all for this group, but I think the most important thing is that, as everyone probably is well aware, not all class B. Firefighting foams contain pfas, and we have a long history of many decades going back to the late 19 sixties of different formulations of actual F itself. And so all of that sort of complicated alphabet soup, with various 56 00:11:41,550 --> 00:11:49,340 Janet Anderson, GSI: versions of 3 F's. You don't have to distill between which, if we're talking about emergency response, foam itself. 57 00:11:49,340 --> 00:12:14,249 Janet Anderson, GSI: Which type of foam, perhaps? Who was the vendor? When was it purchased. How long has it been there? All of those are really important for understanding how to interpret environmental data. So even in the space, there's opportunities to help using analytical chemistry and some tools to differentiate between the different formulations of foam. Perhaps the different manufacturers, the different 58 00:12:14,250 --> 00:12:17,690 Janet Anderson, GSI: timing, and that can help identify different sources as well. 59 00:12:17,740 --> 00:12:45,900 Janet Anderson, GSI: But, as Zach said, it's not just foam. Next slide, we actually know that there's obviously all sorts of different types of projects, products that may contain pfas, many of which may be found on an airport, or, you know, in an environment such as a waste stream, or have some sort of impact near a Dod facility or an airport. So things like coatings and paints and varnishes. If you have a manufacturer who uses pfas as perhaps a 60 00:12:45,900 --> 00:13:02,150 Janet Anderson, GSI: agent in any of those, and they're somehow potential waste stream contributes to the local hydrogeology of your site lubricants and greases. Those are also ones that may result in an environmental release. But next slide 61 00:13:03,156 --> 00:13:06,419 Janet Anderson, GSI: I do want to say that I think it's important to 62 00:13:06,470 --> 00:13:27,880 Janet Anderson, GSI: sort of bring the temperature down just a little bit and remind ourselves, though, that even though we have this narrative, that pfas are everywhere. And there's all kinds of products that contain pfas when we're talking about environmental investigations and environmental releases. We want to think more carefully and specifically about the pfas of relevance. 63 00:13:27,880 --> 00:13:47,019 Janet Anderson, GSI: Why is that? Well, not all pfas are even water soluble. Not all pfas or products that contain pfas will result in a pretty significant waste stream from just a user product, maybe at the manufacturing side, but not at the use side. And so you have to think about the life cycle, the type of pfas. 64 00:13:47,020 --> 00:14:15,199 Janet Anderson, GSI: I think there's some animation on this, Zach for the next. So we consider in our report the pfas of relevance for an environmental investigation, those pfas that may actually end up in the environment. And those really again, are the ones that are water soluble, that are used in a significant amount, or large enough mass, that you may find it as a release in the environment and so bringing us down just a little bit. It's not. The whole universe of pfas 65 00:14:15,430 --> 00:14:19,819 Janet Anderson, GSI: is a subset. The circle. I don't want to differentiate per se. 66 00:14:20,000 --> 00:14:40,160 Janet Anderson, GSI: Some polymers, you have to think about degradation products, especially at the manufacturing site. So, for example, those side chain fluorinated polymers. Maybe those side chains are breaking into pfas of relevance. So there's some nuance there. That's important. I don't think we can just make sort of a generalized statement. We can't ever make generalized statements with pfas, or else it's incorrect. But 67 00:14:40,160 --> 00:14:51,559 Janet Anderson, GSI: polymers that are perhaps not water soluble, not mobile in the environment, perhaps found at very, very de minimis. Concentrations and products 68 00:14:51,870 --> 00:15:06,659 Janet Anderson, GSI: may be important conversations for other applications. But when we're talking about environmental focus, we're really thinking about those pfas that may be found in the environment at a concentration that we can detect, and that may help us understand different sources. 69 00:15:06,740 --> 00:15:09,019 Janet Anderson, GSI: So next slide. 70 00:15:10,080 --> 00:15:11,090 Janet Anderson, GSI: okay. 71 00:15:11,780 --> 00:15:24,679 Janet Anderson, GSI: so when should we even start this conversation when Zach and I work with a wide range of our different types of clients, and at any kind of given site, we often advise our clients to start thinking about potential pfas. 72 00:15:25,000 --> 00:15:28,179 Janet Anderson, GSI: like early, early early in the process, like day one. 73 00:15:28,350 --> 00:15:55,419 Janet Anderson, GSI: what are the potential source areas? Not only on your site, and that you may have contributed to, but also maybe in your watershed or your local hydrogeology. So we're talking early preliminary assessment, and we are guiding our clients to think about. Who are your neighbors? Where's that groundwater flowing? What might be all the different release locations again on your own site. This gets factored into all the work plan steps. 74 00:15:55,480 --> 00:16:01,810 Janet Anderson, GSI: And so really, the bottom line up front on this question is, think about potential pfas source areas 75 00:16:01,830 --> 00:16:14,680 Janet Anderson, GSI: early and often throughout the entire process of a site investigation. Don't wait until you're just trying to do. Maybe a feasibility study right? You really want to think about it and start collecting that data early on 76 00:16:15,320 --> 00:16:16,430 Janet Anderson, GSI: next slide. 77 00:16:18,660 --> 00:16:25,150 Janet Anderson, GSI: So the bottom line question, Zach, maybe if you wanna start talking about this one just a little bit for us. 78 00:16:25,150 --> 00:16:42,289 Zachary Puchacz (Mead & Hunt): Absolutely thanks, Janet. So when we were strategizing how to compile this report together, obviously having data on pfas and test results was important. And we included over 800,000 points of data that you'll learn about here in just a minute. But 79 00:16:42,390 --> 00:17:07,609 Zachary Puchacz (Mead & Hunt): it was also important for us to document the logical approach to investigating sources of pfas. And you'll see here in just a minute. I laugh that when I help my airport clients on this the initial thought is, well, I gotta go out and do some testing. I gotta go out and get environmental consultant. And we're gonna poke some holes in the ground, and that might not be the best 1st step. There's other a lot of other factors to consider. So when we were compiling 80 00:17:07,880 --> 00:17:34,049 Zachary Puchacz (Mead & Hunt): this report together, what we found is that there's really 3. I'll call it focus area buckets. If you want to look at it that way. A lines of evidence approach that makes the most sense, and it involves data collection doing, sampling. And then also looking at advanced forensics. Those are those technologies that you see about in the news headlines. And again, you know, our understanding and our looking at this is that there's not really that silver bullet. I think that's 81 00:17:34,050 --> 00:18:02,930 Zachary Puchacz (Mead & Hunt): common knowledge almost at this point. But it's letting the airport community know that because I get a lot of calls from my airport clients that say, Well, here's my test results. Isn't there something I can compare this to? And it's not exactly that easy. And so that's what this research report was really focused on is that for airports, looking at pfas from a forensic standpoint. What's the best approach to do that? So I'm going to talk about the one that seems so obvious. But what I think is the most important. And that's doing that data collection at Desktop Review. 82 00:18:02,930 --> 00:18:04,160 Zachary Puchacz (Mead & Hunt): And again. 83 00:18:04,200 --> 00:18:15,069 Zachary Puchacz (Mead & Hunt): it seems so simple. I'll just find some records and we're done, but it's not necessarily the case. It can be a challenge to find information, as I like to joke about way back in the day. 84 00:18:15,070 --> 00:18:44,500 Zachary Puchacz (Mead & Hunt): We didn't. We didn't think a triple F was a bad thing, so it was discharged freely, and I like to make the analogy think of 30 years ago you accidentally spilled some ketchup if we find out in the future. Ketchup was a really bad thing for us. Okay, go back and tell me how many times you spilled ketchup right? There's no records of it. So that's really a challenge that airports face. So in trying to figure out where a triple F may have used. There's a lot of different potential resources that we've documented. Yes, it's talking to your firefighting department and 85 00:18:44,500 --> 00:18:55,979 Zachary Puchacz (Mead & Hunt): those that know the airport operations. But it's also looking at some environmental documentation that might be out there and available. You see that list there, and that goes for on and off airport resources as well. 86 00:18:56,130 --> 00:19:16,049 Zachary Puchacz (Mead & Hunt): and in our Acrp report we help airports by documenting what some of these sources are, and how they could benefit. And again, from an airport perspective. You might know what you did. But what about your neighbors? What about the industrial site that was upstream from the airport? So that was really a focus of that. And then pulling all of this data together. 87 00:19:16,430 --> 00:19:33,389 Zachary Puchacz (Mead & Hunt): we've again I feel that that's 1 of the most important steps an airport can take that I've seen overlooked. It's yeah. I talked to my firefighting guy and we think we had a crash 30 years ago. Well, let's dig into that a little bit deeper, and I've even gone as far as just searching historical newspaper records 88 00:19:33,390 --> 00:20:00,840 Zachary Puchacz (Mead & Hunt): to try to see. Well, we knew there was a hangar fire. There was there foam used? Or is there a National or Ntsb. Accident report that we can go to to collect information? And all of that is important from the airport perspective, but also for off airport sources. As well did that oil refinery a mile upstream, that they have a fire, and so that is something we wanted to document and really emphasize. That seems so simple and logical. But a very important 1st step for airports from looking at pfas forensics. 89 00:20:01,100 --> 00:20:15,330 Zachary Puchacz (Mead & Hunt): Janet's gonna talk about the conventional sampling side of it like I joke about. That's just as important, and something that like I said airports mentioned. Hey? I think I got to do that, but there needs to be a logical approach to that, and Janet will talk about it here right now. 90 00:20:16,270 --> 00:20:31,590 Janet Anderson, GSI: Thanks, Zach. So what I found typically happens is there's usually some sample or some known release area. That triggers. The need for an investigation. We know somebody use a triple F 91 00:20:31,650 --> 00:20:47,230 Janet Anderson, GSI: or pfas have been detected in the environment. And so now you've got so you usually have, just like a little bit of a data point. And as Zack said, that that desktop exercise can really help, then prioritize where and how you're going to collect additional data. 92 00:20:47,350 --> 00:21:03,079 Janet Anderson, GSI: But that additional data collection usually starts with just EPA method 1633, or some sort of standard analyte list. That's 40 70, depending on what you pay for. But some sort of conventional analytical sampling. That's what we're talking about here. 93 00:21:03,080 --> 00:21:23,990 Janet Anderson, GSI: You didn't pay for extra analytes. You're not paying for a total organoflurine assay. You're just collecting your groundwater soil, whatever surface water data using virtual labs and using the standard analyte list we do recommend, though, and to our clients and for purposes of later interpretation and decision making. 94 00:21:23,989 --> 00:21:42,949 Janet Anderson, GSI: Get the full set of pfas data as much as you can. We get asked that quite a lot like, hey? So and so lab offers an extended analyte list. Yeah, do it? You know, it's still conventional sampling. We're not talking about anything fancy. But if you can extend on that analyte list, more information is power. 95 00:21:42,950 --> 00:22:08,870 Janet Anderson, GSI: And really, this is when our hydrogeologists and our geologists and and all of our environmental scientists need to shine because we need to develop that conceptual site model. We need to take information and collect some data that helps us understand groundwater flow that helps us understand interconnectivity between different groundwater aquifers or surface water interface between groundwater and surface water or 96 00:22:09,100 --> 00:22:21,189 Janet Anderson, GSI: soil properties. So many times do I see samples collected where the full range of potential soil information isn't collected. And that's really then creating a data gap that challenges interpreting data, later. 97 00:22:21,190 --> 00:22:45,979 Janet Anderson, GSI: stormwater infrastructure and consideration of like movement of surface water and stormwater sewer water. All of that kind of stuff is really critical as part of that conceptual site model. But this is stuff that you can do in these early stages of investigation. If you just think carefully about the fact that this type of information may help you interpret just standard conventional information. For pfas analytes. In the 1st place. 98 00:22:46,929 --> 00:23:08,489 Janet Anderson, GSI: the last 2 bullets are important. And what makes pfas, forensics and source identification complicated because we do have to think about precursor transformation. So that's the weird and wonderful, not fully fluorinated pfas that then can transform in the environment to the fully fluorinated, like 6 chains or 4 chains or etc. 99 00:23:08,490 --> 00:23:32,419 Janet Anderson, GSI: So we do have to think about that. And there are fate and transport differences amongst different pfas, right? And so again, collecting all this information with this understanding that it's not going to be a simple analysis. But the more data you can collect the more robustly you can start looking for outliers and looking for trends and overlaying information of what we do know. The next slide, please. 100 00:23:34,340 --> 00:23:54,210 Janet Anderson, GSI: So, for example, in our Acrp book, we just a report. We really use that massive data set. Thank you to Europeans for helping us with that data. We also scrubbed publicly available data that we could get from sources and locations all over. 101 00:23:54,210 --> 00:24:03,949 Janet Anderson, GSI: And we are able to look at certain patterns. And so these are things, just this pattern identification that you can do with conventional data. And there's a bunch of ways to do this. 102 00:24:03,950 --> 00:24:28,909 Janet Anderson, GSI: You can do the family trees. You can look at ratios of different specific pfas, you can look at the linear versus branch so that helps understand sort of the Ecf versus fluoro telomere products. You can do principal component analysis. So more of a statistical analysis of like outliers and grouping. And you can just plot them. And just look at frequency of occurrence and detection, and start looking at patterns right? 103 00:24:28,910 --> 00:24:42,000 Janet Anderson, GSI: There's a ton of different, of really great publications that are starting to demonstrate what these patterns might look like again. They have to be very carefully interpreted, based on 104 00:24:42,000 --> 00:25:01,010 Janet Anderson, GSI: fate and transport considerations in your conceptual site model, right? But we found consistently looking at over almost a million data points that we had some really clear patterns of what airports environmental data from an airport. So when a triple F source might look like versus, for example, shown here, a wastewater treatment plant. 105 00:25:01,030 --> 00:25:17,619 Janet Anderson, GSI: So we present plots that look at just basic patterns of what pfas may look like for these different source areas. Again, geospatial information, understanding, paint, transport, understanding, conceptual site model, all those have to be part of it. So it's a line of evidence approach. 106 00:25:17,680 --> 00:25:29,509 Janet Anderson, GSI: But with just some standard analytical data, you can start to glean information about patterns and that can help guide them for future focused efforts. 107 00:25:29,540 --> 00:25:30,630 Janet Anderson, GSI: Next slide. 108 00:25:32,740 --> 00:25:51,060 Janet Anderson, GSI: I think I'm not going to go through these. But these again, are just some examples that we have in our report. So there's a ton of different ways that you can plot these data. You can look at them as cumulative concentration plots, as pie charts, as Median concentration, ratio dot plots, heat maps. 109 00:25:51,330 --> 00:25:56,489 Janet Anderson, GSI: spider plots, all of it all the fun stuff next slide. 110 00:25:58,275 --> 00:26:04,794 Janet Anderson, GSI: and again, complicated data interpretation. So colleagues of mine at Gsi have reported. 111 00:26:05,320 --> 00:26:12,760 Janet Anderson, GSI: issued a a citation here that you can find. But again, keep in mind the precursor transformation component. 112 00:26:12,810 --> 00:26:30,090 Janet Anderson, GSI: Keep in mind. This is where maybe understanding the source of the triple F or the age of the Af. Might be helpful. Keep in mind that there are sort of these family trees, or some some groupings of what might be transforming in the environment to terminal 113 00:26:30,090 --> 00:26:49,809 Janet Anderson, GSI: pfas. So I'm not going to get in the complexity of all of that. But there are sort of condensing similar pfas that environmental precursors transform to. And that's important to consider. And I think the next slide shows that pretty well. So in our data, let me go ahead and hit the animation. 114 00:26:50,200 --> 00:27:10,370 Janet Anderson, GSI: For example, Pfhxa, the 6 chain carboxylic acid shows up in everything right? Why? Well, because it's a terminal transformation project, product of all sorts of different higher chain precursors. So that's not going to be a very good distinguishing pfas. Right? 115 00:27:11,207 --> 00:27:14,280 Janet Anderson, GSI: Next slide. I think I have just a few more. 116 00:27:14,650 --> 00:27:40,240 Janet Anderson, GSI: So I know we keep saying this a little bit over and over, but I think it's just important for people to understand there's no such thing. Yet as a definitive signature using the conventional commercial data. So it's really important to, you know, vocalize. What are our objectives at this stage using the commercial data, it's really to inform whether additional forensic analysis is warranted or needed, or going to be helpful. 117 00:27:40,270 --> 00:27:46,799 Janet Anderson, GSI: 1st of all, second of all, to help maybe guide sampling programs and more detailed site investigation. 118 00:27:46,840 --> 00:28:01,320 Janet Anderson, GSI: So it's critical to carefully look at this information on top of your conceptual site model. Think about your multiple lines of evidence, everything from your desktop review. What do you know to be local in the area? How do you know your groundwater is flowing, etc. 119 00:28:01,350 --> 00:28:13,099 Janet Anderson, GSI: But there's some decision logic, and some rationale that you can build using the commercial data before you pull that trigger to go to the more sophisticated analytical tools and forensic tools that we have available. 120 00:28:13,950 --> 00:28:14,910 Janet Anderson, GSI: And 121 00:28:15,190 --> 00:28:21,319 Janet Anderson, GSI: and to walk us through that, we developed a desktop. And I think, like a tool. And I think Zack's gonna walk through that next. 122 00:28:23,270 --> 00:28:24,290 Janet Anderson, GSI: maybe. 123 00:28:24,450 --> 00:28:40,649 Janet Anderson, GSI: Oh, I guess I have one more slide. Sorry. So again, the results from the conventional data identify data patterns identify, maybe where there might be alternative source areas. And then that helps prioritize next actions. Zach, once you walk us through the tool, yeah. 124 00:28:41,570 --> 00:28:56,029 Zachary Puchacz (Mead & Hunt): Absolutely. Thank you, Janet. So the one neat thing about this Acrp report is, there's an excel spreadsheet tool that's available, and I should note that the report is available online for free. So again, if you do a quick Google search for Acrp 125 00:28:56,030 --> 00:29:19,330 Zachary Puchacz (Mead & Hunt): report 255, you should be able to find us. I want to include a link, but it ended up being about 3 or 4 lines of characters to try to remember. So I think it's easier if you just as I said Google, the report. But there's a excel spreadsheet based tool that's available. And there's 2 parts of the tool. The 1st one is very specific oriented towards airports, and it's really to help airports through that desktop review process I talked about earlier. 126 00:29:19,330 --> 00:29:32,979 Zachary Puchacz (Mead & Hunt): and in aviation we use a lot of checklists to make sure that we are. We have all the right procedures completed. And so that's really what this tool is focused on, and it provides a background. Have you considered checking this off site resource? 127 00:29:32,980 --> 00:29:57,919 Zachary Puchacz (Mead & Hunt): Have you talked to someone on your airport, etc? And if I go to the next slide here. Really, that end result for the airport interest in using this tool is to provide a a score and indicator. It's not really a way of comparing how you've done with other airports, but just a way of making sure you've checked all the boxes to make sure you understand. That you have those that desktop information that you need. 128 00:29:57,920 --> 00:30:17,179 Zachary Puchacz (Mead & Hunt): What's also included in the tool, which I think has a value to those outside of the aviation interest is that we provided there's a lot of disclaimers associated with the second tool. But with those 800,000 data points of Pfast we look at, we looked at those in the I'll call them fingerprints. 129 00:30:17,180 --> 00:30:29,999 Zachary Puchacz (Mead & Hunt): Wanna make sure I use the right word here. It's not definitive, but looked at how those visualizations looked at appeared that Janet talked about earlier, where there's a few summary graphics in the report and try to 130 00:30:30,240 --> 00:30:45,219 Zachary Puchacz (Mead & Hunt): provide. I'll call it a generalization that if you had if you went out and tested for pfas, and you had your results of what was found and the levels to plug those into the spreadsheet tool and compare them with some pie charts from the data that we've developed. 131 00:30:45,220 --> 00:31:09,760 Zachary Puchacz (Mead & Hunt): so you may have to squint your eyes a little bit there. But on the right side of this slide, you'll see that there's some pie charts representing airport, a triple F or industrial or chrome plating. For example, if you squint your eyes down there. There is a few very select general categories that we wanted to provide a point of reference, so that if an airport, or if someone had some pfas results. 132 00:31:10,090 --> 00:31:37,289 Zachary Puchacz (Mead & Hunt): The tool is set up where you plug in the compounds that you found in the values you hit enter, and then it produces a pie chart that you can use to compare with some of our results. And this is where we like to have a lot of disclaimers, because it sounds like, oh, this is that magic bullet. This is how I'm going to know if it's a triple F or somebody else's. This is a good I'll call it initial. Step in that process that if you're seeing some signatures that align with one of our pie charts 133 00:31:37,290 --> 00:32:00,109 Zachary Puchacz (Mead & Hunt): that give you some that gives you some information to make some decisions or the opposite. Let's say you plug information in, and nothing matches any of the pie charts again. That gives you a path to make some decisions and and help go down that forensics path. So again, that's an excel spreadsheet. That's a part of the research report. It's available for free like, I said, Google, Acrp report 255, and you'll have access to this. 134 00:32:01,150 --> 00:32:19,700 Zachary Puchacz (Mead & Hunt): So to finish our 3 lines of evidence approach. The last one is advanced forensics, and it's real easy to read news headlines and get very excited about a new technology that's being worked on in the lab, and they're very exciting. But I think it's important, especially for the airport community to consider 135 00:32:19,996 --> 00:32:45,210 Zachary Puchacz (Mead & Hunt): the technologies that are available to them, and when to use it. Some technologies are still in the I'll call it marketing development type stage, where they're really pushing it. I get a lot of those calls for my airport clients about. Hey? Let us let us try this at your facility. But it's really that. Is it proven? Is there a background to it. I know our partners at Patel. Part of our team have some technologies that are are very beneficial 136 00:32:45,210 --> 00:33:13,309 Zachary Puchacz (Mead & Hunt): out there. Obviously, there's a lot of considerations with using those technologies. Does it make sense? There's some shortcomings in those technologies as well, just like anything else that's out there in the world. And so we wanted to document that in our report, so that when the airport community, when users of this document are thinking about advanced forensics again, we have that as I like to joke in aviation. We like to have a checklist, those checklists of considerations of. Is this appropriate? Does this make sense 137 00:33:13,310 --> 00:33:17,270 Zachary Puchacz (Mead & Hunt): for the particular pfas forensic situation. The airport might be facing 138 00:33:18,740 --> 00:33:29,510 Zachary Puchacz (Mead & Hunt): so to wrap up our conclusion, as I like to tease with my airport clients. Yes, there's this research report out here on forensics. But there's still a lot to be learned 139 00:33:29,510 --> 00:33:52,499 Zachary Puchacz (Mead & Hunt): about forensics for various reasons for transformation of these compounds in the environment, just our our lack of understanding. We know a lot about this, but there's still a lot of research that needs to be done. So we like to emphasize. I do. We have it in our report that there's not a silver bullet when it comes to pfas forensics. There's not that one thing you can do to determine. Is it a triple F, is it mine? Is it from off site? Etc. 140 00:33:52,500 --> 00:34:06,970 Zachary Puchacz (Mead & Hunt): And really that lines of evidence approach? That's where you get the greatest value, is looking at that desktop review, looking at what I would do if I needed to go out and do sampling, and then looking at advanced forensics, does it make sense to have a technology come in to help us do that. 141 00:34:07,190 --> 00:34:08,600 Zachary Puchacz (Mead & Hunt): And again. 142 00:34:08,790 --> 00:34:33,910 Zachary Puchacz (Mead & Hunt): this lines of evidence approach having one who's knowledgeable about pfas is very important as well. So having someone on staff that understands pfas or having an environmental consultant again from my world on the airport side, airports want to immediately hiring that hire that sample company to go out and to do that sampling. But there needs to really be a strategy. There needs to be a well thought out 143 00:34:33,910 --> 00:34:41,799 Zachary Puchacz (Mead & Hunt): concept, site development model to determine all right. How are we going to approach this to make the best decisions we can on tfas forensics? 144 00:34:43,730 --> 00:34:59,849 Zachary Puchacz (Mead & Hunt): So with that. I think that's all that Janet and I had prepared. We are happy to answer questions, and I think we have some time now and then I think we're also planning on hanging around at the end of the day as well. If you think of something after after our time here. 145 00:35:02,190 --> 00:35:05,470 FRTR Presenter: All right. Thank you. So let's give them a round of applause. 146 00:35:09,680 --> 00:35:20,759 FRTR Presenter: All right. I do see questions online. But before I turn to those anyone in the room. So remember our our guests and steering committee members at the table. You have mics in front of you 147 00:35:21,790 --> 00:35:23,320 FRTR Presenter: members of the audience. 148 00:35:24,730 --> 00:35:27,879 FRTR Presenter: All right. Well, I'm going to start with these online questions. 149 00:35:27,920 --> 00:35:50,159 FRTR Presenter: Zach and Janet, you said Tool. And that's the magic word sometimes to people who have problems. So I have a lot of questions asking about the tool you've already answered, how they can get the tool. So I'm going to put that link out there for the online audience for anybody in the room. I'll have a QR. Code here in a minute, so you can come and scan. I found it for you. 150 00:35:50,160 --> 00:36:06,369 FRTR Presenter: But there are a number of people that are asking, is there a Mac version of the tool? Are there mobile versions of the tool? Do they need to install something or get special permissions. How frequently are you updating the tool? So lots of questions about the tool. 151 00:36:07,330 --> 00:36:11,294 Zachary Puchacz (Mead & Hunt): Absolutely, Janet, I can start and you can fill in the blank. So 152 00:36:11,970 --> 00:36:35,600 Zachary Puchacz (Mead & Hunt): when you go to the Acrp report website, as far as the technical questions about the tool. There's some information provided there on how to download it. If you have a Mac, for example. So there is some information there. If you run into any snafus on that and reach out to me, reach out to a member of our team and we can reach out to our contact member at Acrp to help you through those those technical items 153 00:36:35,600 --> 00:36:54,909 Zachary Puchacz (Mead & Hunt): to answer the question about the update of the tool? That's a great question. And I'm going to lean back on the plug I had earlier for Acrp, and with Acrp there have been projects where research has been updated over time, and that's a item that we had thought about on our team as well is 154 00:36:54,910 --> 00:37:13,860 Zachary Puchacz (Mead & Hunt): this is a point in time. But what if things change so our contract. Unfortunately, right? We fulfilled the terms of our contract. But I see that as important, and I would encourage those that see value in that to submit a proposal idea, the Acrp. To have that tool updated on a future effort. 155 00:37:14,170 --> 00:37:17,809 Zachary Puchacz (Mead & Hunt): Janet. I don't know there's anything I I missed there on the technical side of what went into the tool. 156 00:37:18,353 --> 00:37:24,328 Janet Anderson, GSI: No, nothing. It was on the technical side. I think I also wanna just put a plug in for the updating because, 157 00:37:24,770 --> 00:37:47,029 Janet Anderson, GSI: our report goes through a lot of detail of what data we use, those over 800,000 data points. And as everyone knows, any data is only good as, or any model or tool that comes out of data is only as good as the data and most of the data collected to date with, well, a lot of it was collected using a very small subset of pfas, or in 158 00:37:47,330 --> 00:38:10,039 Janet Anderson, GSI: a lot of Dod data and a lot of a data. And so it was heavily, heavily weighted on the side. And we had limited data in some of the other source categories. And so I think, as we get more information on site characterization of different types of release areas that'll be helpful. We also had no geospatial information in the data point. So an aff 159 00:38:10,370 --> 00:38:25,818 Janet Anderson, GSI: sample. But was it source, or was it distal? Or you know, how? How did that work? The assumption is that when you put all of that together, that we had a good mix of a whole bunch of different types of information. You still pick up patterns? 160 00:38:26,180 --> 00:38:42,600 Janet Anderson, GSI: and we did. But I think that's the type of stuff that needs to be updated. Better data, more data that's representative of other types of sources and more complex understanding of those data meaning geospatial or time 161 00:38:42,860 --> 00:38:44,530 Janet Anderson, GSI: differences as well. So. 162 00:38:46,180 --> 00:38:58,180 FRTR Presenter: Alright, and for those who may have highly secure devices, that if they're unable to download things, could they reach out to either of you directly to obtain copies of the tool 163 00:38:58,840 --> 00:38:59,830 FRTR Presenter: absolutely. 164 00:38:59,830 --> 00:39:00,950 Zachary Puchacz (Mead & Hunt): Absolutely. Yes. 165 00:39:01,770 --> 00:39:12,860 FRTR Presenter: All right. Thank you. We have a question that came in earlier. One of the attendees wondered if you could discuss again what soil properties do you feel are important to be collected for a pfas site? 166 00:39:13,760 --> 00:39:34,619 Janet Anderson, GSI: Sure there's a lot of great publications and ongoing work related to that. We have found that obviously the total organo carbon contents important. The Ph, the grain size, all the the real standard stuff is pretty important. But get that exhaustive list. So understand all of that ph 167 00:39:34,630 --> 00:39:51,360 Janet Anderson, GSI: organic carbon content, particulate size, grain, size, type of soil, soil, characterization like, is it, you know, a loomy, sandy clay. What is it? You know? Characterizations of the soil type there, too, all of that is really important. 168 00:39:51,380 --> 00:40:06,110 Janet Anderson, GSI: And that type of information is really helpful and sort of like that principal component analysis type of thing where you can look to see I see something different in my pattern. Let's lay on top of that, some soil characteristics. And does that explain the difference? 169 00:40:06,250 --> 00:40:09,170 Janet Anderson, GSI: If the answer is No, hmm. Maybe there's a different source. 170 00:40:11,490 --> 00:40:17,069 FRTR Presenter: All right. Let me turn back in the room. Any questions from our in person. Audience. I see one in the back. 171 00:40:20,070 --> 00:40:28,300 FRTR Presenter: Hi! Good morning I I had a question about how far along has this guidance document, or any other documents 172 00:40:28,790 --> 00:40:31,989 FRTR Presenter: kind of gotten on sources 173 00:40:32,750 --> 00:40:36,679 FRTR Presenter: really kind of the the concrete outside of hangers 174 00:40:36,800 --> 00:40:40,340 FRTR Presenter: as a potential, you know, source to surface water. 175 00:40:40,716 --> 00:40:43,680 FRTR Presenter: How much research has been done on that so far. 176 00:40:44,850 --> 00:40:59,639 Janet Anderson, GSI: We did not address that in this report we acknowledge that that you know that the concrete that has been impacted may be a continual source. There are separate dod funded sort of Bstcp projects ongoing right now, looking at that 177 00:41:00,150 --> 00:41:12,939 Janet Anderson, GSI: and the next speaker, actually, that talk may have some more information on that. I know that they're tracking that as well. But, Zach, I don't know if you have any additional insight. And you I know you've looked at some of this at some of your site. Specific work. 178 00:41:12,940 --> 00:41:21,740 Zachary Puchacz (Mead & Hunt): Yes, that's a great question. And that's really something that we're facing from the airport construction project side of the world right now that I'm also involved in is 179 00:41:22,140 --> 00:41:42,809 Zachary Puchacz (Mead & Hunt): how much of a concern is that? And concrete's a porous material, right? So in theory, if there's enough of it over time, it can seep through. However, it does have some rigidity to it that can prevent that can be a cap, I guess, or a barrier might be another way of saying it. So I am aware of some concrete 180 00:41:42,810 --> 00:41:59,329 Zachary Puchacz (Mead & Hunt): pfas testing technologies out there that our next presenter maybe could provide more detail on. If you're interested in those reach out to me. I know that I've been following that. It's something that I've been considering. We have done that on some airport projects, but we've done that 181 00:41:59,330 --> 00:42:10,619 Zachary Puchacz (Mead & Hunt): modifying some EPA laboratory methods in order to get results, because there's not really anything out there that we can point to saying. This is how you test for it in concrete. 182 00:42:10,630 --> 00:42:22,129 Zachary Puchacz (Mead & Hunt): So, without spending too much time, feel free to reach out to me, and I can connect you with some resources that I've been following on on about that. But it's it's a really great question, something that airports are thinking about right now. 183 00:42:22,940 --> 00:42:24,929 FRTR Presenter: And we have another question in the room 184 00:42:25,530 --> 00:42:27,003 FRTR Presenter: for the 185 00:42:27,940 --> 00:42:36,749 FRTR Presenter: pie charts that you were showing in your slide is, are you meant to enter groundwater data, surface water data, soil data? Or is it? Does it not matter. 186 00:42:40,100 --> 00:42:54,150 Zachary Puchacz (Mead & Hunt): Janet, we can probably both half answer and not answer that question at the same time, since our our partners at Terracon are really involved with that. So the idea with That is a a little bit of both. And the 187 00:42:54,512 --> 00:43:08,457 Zachary Puchacz (Mead & Hunt): there's some vagueness to what we did, and there was some intentionality with that vagueness, because we wanted to make sure that there wasn't the Aha. So what we were really looking at was groundwater with those water results that you get 188 00:43:09,050 --> 00:43:27,309 Zachary Puchacz (Mead & Hunt): You know, I say, tested for groundwater. But drinking water as well. The surface water. So that's really that was kind of the focus of developing that. And if you're interested in more like, I said, we can reach out to our teaming partners with Terracon, which was really the the brain, the brain trust behind that tool. And Janet. I don't know if I missed anything technically or misspoke. 189 00:43:27,570 --> 00:43:39,920 Janet Anderson, GSI: No, I mean, the the bluff statement is that it's it's a groundwater. Heavy data set water data set. So drinking water groundwater and surface water that's sourced. So those pie charts were generated with that. 190 00:43:41,740 --> 00:43:46,930 FRTR Presenter: Okay, I have a comment and question online, oh, sorry. One more in the room. And then I'll go back online. 191 00:43:50,560 --> 00:44:07,459 FRTR Presenter: you for the presentation. My name is Bobby, who's in Rc. We do lots of analysis for the risk analysis, and brought to my attention the presentation. One of the slides about the uncertainty. It is very important, because when we move forward 192 00:44:07,610 --> 00:44:15,650 FRTR Presenter: in this workshop in order to address the risk, so it's very important also to think about the uncertainties. 193 00:44:15,750 --> 00:44:30,070 FRTR Presenter: So the uncertainty is very complicated question in this case, because you are talking about differentiation of the source you are talking about source model, and so on. So it would be a good idea if you could summarize for us 194 00:44:30,150 --> 00:44:41,420 FRTR Presenter: what are the elements of the uncertainties, and what to look for, and what are the most sensitive parameters when we move forward, try to address the risk 195 00:44:41,500 --> 00:44:59,270 FRTR Presenter: from the different sources, and what kind of risk we are talking about and the potential impacts for the public. We're talking about psychology. But also we need to think about the risk slow factors, according to EPA for the chemical risk. 196 00:44:59,310 --> 00:45:10,230 FRTR Presenter: So if you can elaborate more so, this could help us in our discussion when we move forward. When we talk about the risk analysis in this workshop. Thank you. 197 00:45:11,060 --> 00:45:17,360 Zachary Puchacz (Mead & Hunt): Absolutely. And, Janet, I can start. And you can add in. So from the airport perspective. 198 00:45:17,490 --> 00:45:47,220 Zachary Puchacz (Mead & Hunt): the real challenge with, there's 2 challenges. There's obviously number one is protecting human health, right? So if there's a release of a triple F on site, and somehow that pfas migrates off site and it's in drinking water. That's the number one concern with everybody from an airport specific perspective. Selfishly, it's the who's responsible for the pfas. There are some situations I'm aware about out there where there's a known off off airport pfas release. 199 00:45:47,220 --> 00:45:57,090 Zachary Puchacz (Mead & Hunt): And in the mindset of the Regulators it's well it's coming from the airport, and the finger immediately gets pointed at the airport, and that might be true. But are there other contributors to that? 200 00:45:57,100 --> 00:46:25,400 Zachary Puchacz (Mead & Hunt): Is that from the industrial facility off site? Is that from an oil refinery upstream as well. So that's really the challenge. And now you're starting to dive into risk management and legal, and obviously I'm not a paid lawyer, nor do I play one on TV. So that's a whole nother conversation, but from the airport perspective, as far as pfas forensics. Those are the the 2 big considerations on their mind. In looking at how to approach this. 201 00:46:26,270 --> 00:46:52,690 Janet Anderson, GSI: And I think it's important to recognize that I do feel strongly that, having a good conceptual site model and having really as well as we can identify and say, site, characterization, characteristics, characterization done to help inform the risk assessment. And then all of that together to help inform remedial decisions is critical, right? Certainly there's going to be uncertainty. Certainly there's going to be data gaps. 202 00:46:52,830 --> 00:47:00,050 Janet Anderson, GSI: We can't let the perfect be the enemy of moving forward. But we? Really, from a risk perspective. 203 00:47:00,780 --> 00:47:13,120 Janet Anderson, GSI: You know, the bugs and bunnies and human receptors don't care where the chemical came from. The importance is that there's a complete exposure pathway, and there is a need to mitigate that exposure to protect human health of the environment. 204 00:47:13,270 --> 00:47:30,599 Janet Anderson, GSI: The challenge, then, is defining and maybe prioritizing where the risk is coming from, what the chemical is, and then where this type of investigation is laid on top of a risk assessment, what can meaningfully be done to help mitigate that risk. 205 00:47:30,600 --> 00:47:45,510 Janet Anderson, GSI: If we're focusing our remedial action on just one source. And it's not the only source are we really able to effectively protect human health and the environment. We really need to think holistically and trying again to not get into the 206 00:47:45,510 --> 00:48:08,569 Janet Anderson, GSI: finger pointing. And and that aspect of you know, who's going to pay for it and what's being done. But just from A, we want to protect human health and the environment. Therefore we really need to understand all the potential pathways of exposure and all the potential sources. Where's the greatest mass coming from? Is there still ongoing, you know, releases from a source zone. Is there contributions from an upstream source that even if I 207 00:48:08,650 --> 00:48:13,790 Janet Anderson, GSI: do my best and spend as much resources I can to clean up here, there's still gonna be incoming 208 00:48:13,910 --> 00:48:31,260 Janet Anderson, GSI: contaminants that might be presenting a risk. All of that is part of effective risk management strategies. And so that's where I think even then this discussion of alternatives. And what are those chemistries? It's really about the exposure pathways. And that's where the exposure piece is so critical. 209 00:48:31,310 --> 00:48:43,299 Janet Anderson, GSI: What is that exposure pathway where they complete. And where are the chemicals coming from? What's that transport from the release to the receptor and making sure that we're designing mitigation strategies that really are going to be effective. 210 00:48:44,000 --> 00:49:12,749 Zachary Puchacz (Mead & Hunt): And and, Jen, if I can quickly add back in here, you know, from the alternative standpoint, you know airports. There's 2 factors affecting them financially. Number one is, they're definitely not a money making entity. Maybe your larger airports make some money, but a lot of airports are very constrained on their budget. But the other consideration is that with airports receiving a lot of Federal funding from the Faa, there's restrictions on how they can use that money. And so that's another big issue is that if somebody has an idea for an alternative. 211 00:49:12,750 --> 00:49:34,759 Zachary Puchacz (Mead & Hunt): there was one airport where there was an idea of from from an off airport interest about putting a water treatment plant in the airport airport. No way has the budget to run that. So in looking at alternatives that was really the focus of our research was, what's that logical, I say, cost effective. I don't want to say cheap. But if you have finite resources, what's the best way to approach this.