WEBVTT 00:00:00.000 --> 00:00:00.000 And with that, it is my pleasure to welcome everyone to today's internet seminar. You should be joining us for part one of a two-part webinar series on the framework for investigating asbestos contaminated circle sites. 00:00:00.000 --> 00:00:00.000 My name is Jean Balance coming to you from EPA's Technology Innovation and Field Services Division, where I will be serving as a technical moderator in the background for today's broadcast. 00:00:00.000 --> 00:00:00.000 And we're joined by a series of technical experts who will be helping to answer questions and facilitate conversations during our broadcast. 00:00:00.000 --> 00:00:00.000 But before I officially launch into the presentation content and then we begin our Q&A breaks. 00:00:00.000 --> 00:00:00.000 What I'd like to do is walk through a series of housekeeping items to make sure that everyone understands how to participate in today's broadcast. 00:00:00.000 --> 00:00:00.000 The first important reminder is that there is a unique seminar homepage for our session today. 00:00:00.000 --> 00:00:00.000 That homepage is found at the URL shown in red at the top of the slide. You can access it by the QR code that I have in the lower right on the screen. It's also the same website that you were directed to when signing up. It's the same website that I sent you to. 00:00:00.000 --> 00:00:00.000 Via my confirmation and reminder emails. And it's the same website that I'll send you to if you're looking for copies of the presentation materials, the framework document, and a whole slew of resources that will be highlighted in today's broadcast. 00:00:00.000 --> 00:00:00.000 That website will remain active from today forward. So you're welcome to bookmark it or send it to other colleagues if they'd like to access the very same resources that we'll be discussing on today's broadcast. 00:00:00.000 --> 00:00:00.000 Just a point of note, we do have the website broken down into a series of sections. There's already materials posted under the webinar slides and references area. 00:00:00.000 --> 00:00:00.000 You may find it helpful to slide or scroll up and down or use those plus and minus icons on the right side to collapse and expand sections as needed. 00:00:00.000 --> 00:00:00.000 All right, today we're going to be hosting today's session live through Zoom. You should be able to participate using the free Zoom application or through a web browser of your choice. 00:00:00.000 --> 00:00:00.000 Now, if you have technical difficulties with Zoom and you can't get in on a browser either, there is an optional item. One of the last things you'll see when you check in online for cluwin to simply download the presentation materials and follow along via the optional call-in line. 00:00:00.000 --> 00:00:00.000 Regardless of how you're participating, whether only on the phones or through Zoom, through your preferred audio. 00:00:00.000 --> 00:00:00.000 Please know that we automatically mute all participants, so there's no need to mute yourself or look for a mic icon. We have already taken care of that for you. 00:00:00.000 --> 00:00:00.000 I encourage you to check your local volume settings to ensure that Zoom is coming through loud and clear. If you can, disconnect from local VPNs. That can help improve the quality of the broadcast. But if you continue to experience any issues, please let me know by sending a message to me in the Q&A and I'll work with you to troubleshoot those problems and get you on board for a fully interactive delivery. 00:00:00.000 --> 00:00:00.000 Now, as I noted earlier, for those of you joining in Zoom, there should be a series of icons at the bottom center of your screen. 00:00:00.000 --> 00:00:00.000 The meeting chat has been disabled, meaning that you can't send messages into the chat, but I, as the moderator may periodically send links or references to you through that chat. 00:00:00.000 --> 00:00:00.000 If you have a question, comment, or need to report a technical issue, you'll instead use another icon at the bottom of your screen called the Q&A. So if you haven't used this before, go ahead and click that Q&A button now. 00:00:00.000 --> 00:00:00.000 You'll see a new window open up on your screen. It may pop out on the right. It may be floating in the middle. I encourage you to find a space that's comfortable, put it there and leave it open throughout the broadcast. 00:00:00.000 --> 00:00:00.000 We will pause throughout our session today and take questions from the live audience so that our experts can respond to them. But there is no need to wait for those designated breaks. In fact, I encourage you to type them up as soon as they occur to you. 00:00:00.000 --> 00:00:00.000 If you have any issues, again, you can also report those using the Q&A space throughout our broadcast today. 00:00:00.000 --> 00:00:00.000 We do have live closed captioning available for those of you that need the services. Please look for a CC or caption icon at the bottom of your screen. 00:00:00.000 --> 00:00:00.000 And use those controls locally in Zoom to adjust the size, color, and speed as needed. 00:00:00.000 --> 00:00:00.000 We are recording today's session and the entire series will be archived on the Kluwen website. You'll automatically get an email when the archive is available for on-demand replay. And please stick with me until the very end because I'm going to walk through some important reminders including how you can receive a certificate of participation based on today's session. So visually, I know many of you are already familiar with Zoom, but I've had two people ask me to do this already. So just quickly, if this is brand new to you. 00:00:00.000 --> 00:00:00.000 The controls typically appear on the bottom of Zoom. So audio controls will appear in the lower left. 00:00:00.000 --> 00:00:00.000 With the presentation materials occupying the main portion of your screen. We'll periodically have speaker videos off to the side, but you have additional controls in the upper right and upper center. 00:00:00.000 --> 00:00:00.000 Under a view or presenter screen menu that you can use to adjust the size and scale of content as needed. 00:00:00.000 --> 00:00:00.000 And then the rest of the icons you'll be using are at the bottom center. The CC button to get to that live computer generated closed captioning, and the all important Q&A window that you can use to send in your questions, comments, or to report technical difficulties at any time. 00:00:00.000 --> 00:00:09.000 Now, I think that's the end of the technical reminders that I have. So with that, I'm going to ask the audience to go ahead and send in a quick message to me in the Q&A if you are ready to get started. 00:00:09.000 --> 00:00:34.000 As I'm waiting for some of those messages to come in, I'm going to go ahead and start teeing up the presentation materials so that we can officially launch So looking at all of those messages that you are ready to go with today's part one of the framework for investigating asbestos Contaminated circulates, let me pull up the presentation content and get started with our broadcast today. 00:00:34.000 --> 00:00:40.000 This training was developed by the Asbestos Technical Review Workgroup. Or TRW. 00:00:40.000 --> 00:00:47.000 It aligns with the recent update to the framework for Investigating Asbestos Contaminated comprehensive environmental response. 00:00:47.000 --> 00:00:57.000 Compensation and Liability Act. Or circla sites, which was also developed by the Asbestos TRW. 00:00:57.000 --> 00:01:06.000 The asbestos is comprised of members from regional offices. Office of Land and Emergency Management. 00:01:06.000 --> 00:01:16.000 Or OLIM, Office of Research and Development. Or ORD, and the Agency for Toxic Substance Disease Registry or ATSDR. 00:01:16.000 --> 00:01:22.000 Their mission is to provide technical support for questions concerning the assessment, removal. 00:01:22.000 --> 00:01:27.000 Or remediation of asbestos contamination at circler sites. 00:01:27.000 --> 00:01:33.000 They can answer any questions regarding this presentation or other asbestos related questions. 00:01:33.000 --> 00:01:41.000 For Superfund site assessments. The hotline email address is asbestoshelp at epa.gov. 00:01:41.000 --> 00:01:51.000 Or you can contact your regional or office representative. Contact information for the asbestos TRW co-chairs can be found using this link or QR code. 00:01:51.000 --> 00:01:59.000 Which directs you to the asbestos TRW Technical Assistance website. 00:01:59.000 --> 00:02:07.000 An updated framework for investigating asbestos contaminated surplusites was released in 2021. 00:02:07.000 --> 00:02:16.000 This document updated a 2008 version. The QR code and the hyperlink on this slide will take you to the updated document. 00:02:16.000 --> 00:02:23.000 It provides Superfund regional remedial and removal project managers. On-scene coordinators. 00:02:23.000 --> 00:02:32.000 Site risk assessors, and other site decision makers with information to assist in asbestos risk evaluation at Superfund sites. 00:02:32.000 --> 00:02:44.000 It recommends a site-specific approach to using air measurements of asbestos fibers released during soil and dust disturbing activities. 00:02:44.000 --> 00:02:51.000 This flowchart is a condensed outline of the investigation process described in the updated framework. 00:02:51.000 --> 00:02:59.000 The investigation process outlined in the updated framework follows the traditional remedial investigation or RI process. 00:02:59.000 --> 00:03:09.000 With some deviations due to the unique properties of asbestos. This is a flexible process which allows users to take response action at any point. 00:03:09.000 --> 00:03:12.000 We will circle back to this process near the end of this training. 00:03:12.000 --> 00:03:17.000 Where we will go through each of the steps within this flowchart one by one. 00:03:17.000 --> 00:03:24.000 Before that, we will review the definition of asbestos. An asbestos sampling, and analytical recommendations. 00:03:24.000 --> 00:03:34.000 Asbestos risk assessment recommendations are provided at the end of this presentation. 00:03:34.000 --> 00:03:39.000 What asbestos is depends on the perspective of who is describing it. 00:03:39.000 --> 00:03:44.000 Geologists will describe asbestos based on its mineral type and morphology. 00:03:44.000 --> 00:03:55.000 Commercially, asbestos is used in manufacturing for its beneficial properties. For example, thermal and chemical resistance tensile strength and durability. 00:03:55.000 --> 00:04:00.000 And produces asbestos containing material or ACM. 00:04:00.000 --> 00:04:06.000 The amount of asbestos in a product determines if the material is considered ACM. 00:04:06.000 --> 00:04:17.000 A laboratory analyst will describe asbestos based on what they see and sample under a microscope. For example, fiber dimensions and morphology characteristics. 00:04:17.000 --> 00:04:26.000 Different agencies and organizations that regulate asbestos We'll describe the properties or characteristics of the type of asbestos that they regulate. 00:04:26.000 --> 00:04:36.000 Depending on your audience, you may need to describe asbestos to ensure you are talking about the same thing. 00:04:36.000 --> 00:04:46.000 In geological terms, asbestos is a silicate. Silicates are minerals containing silicon and oxygen In a tetrahedron-shaped ionic group. 00:04:46.000 --> 00:04:55.000 Abbreviated as SIO4. They are also classified by distinct crystalline structures and different cations, such as calcium. 00:04:55.000 --> 00:05:00.000 Ferrous iron, aluminum. Magnesium, etc. 00:05:00.000 --> 00:05:09.000 In mineralogy, the characteristic external shape of an individual crystal or aggregate of crystals is called the crystal habit. 00:05:09.000 --> 00:05:19.000 The habit of formation for asbestos fibers refers to the unusual crystallization habit of a mineral when crystals are thin, hair-like fibers. 00:05:19.000 --> 00:05:26.000 This characteristic habit is called asbesta form. 00:05:26.000 --> 00:05:34.000 There are over 60 known varieties of asbestos. They are usually classified into one of two mineral groups. 00:05:34.000 --> 00:05:39.000 Serpentine or amphibole? Serpentine has a wavy appearance. 00:05:39.000 --> 00:05:48.000 Whereas amphibles appear as straight needle-like fibers. Chrysotile is the only type of asbestos that is serpentine. 00:05:48.000 --> 00:05:56.000 Most asbestos that is used in man-made products is chrysotile. There are several types of amphibole asbestos. 00:05:56.000 --> 00:06:02.000 Including amycite, crocidolite. Anthopholite, actinolite. 00:06:02.000 --> 00:06:08.000 And tremolite. 00:06:08.000 --> 00:06:14.000 Chrysotile is known as white asbestos. It is the most common type of asbestos used around the world. 00:06:14.000 --> 00:06:26.000 With some countries still permitting controlled use. Approximately 93% of asbestos containing materials or ACM, is made up of chrysotile. 00:06:26.000 --> 00:06:34.000 Examples of chrysotile containing ACM include cement pipe and sheets. Roofing, thermal and electrical insulation. 00:06:34.000 --> 00:06:45.000 Flooring, gaskets. Brake pads and shoes, coating and compounds and millboard. 00:06:45.000 --> 00:06:55.000 Crocytolite is known as blue asbestos. It is rarely used in commercial products it is less heat resistant than other asbestos fibers. 00:06:55.000 --> 00:07:00.000 However, it can be found in steam engines. Spray on coatings. 00:07:00.000 --> 00:07:07.000 Pipe insulations, plastics. And submit products. 00:07:07.000 --> 00:07:16.000 Amycite is known as brown asbestos. It is most frequently used in cement sheets and high temperature high heat capacity pipe insulation. 00:07:16.000 --> 00:07:23.000 As it has a high level of heat resistance. 00:07:23.000 --> 00:07:30.000 Anthophyllite is one of the rarest types of asbestos. Its coloring can vary from gray to green. 00:07:30.000 --> 00:07:35.000 Brown and beige. It does not have a long history of commercial use. 00:07:35.000 --> 00:07:39.000 But can be found in cement, insulation. Roofing material, and rubber. 00:07:39.000 --> 00:07:48.000 Due to being relatively inert and stable in the presence of heat or acid. 00:07:48.000 --> 00:07:54.000 Trimolite can be brown, white. Green, gray, or transparent. 00:07:54.000 --> 00:07:59.000 Actinolite can be pale to dark green. Yellowish green and black. 00:07:59.000 --> 00:08:05.000 And appears to be white or transparent. Both are rarely included in commercial products. 00:08:05.000 --> 00:08:10.000 They're usually found in trace amounts when other minerals are being mined. 00:08:10.000 --> 00:08:29.000 But high levels have been identified in vermiculite ore. Mining vermiculite ore with tremolite And actinolite has led to widespread exposures and adverse health effects, as seen at the Libby mine in Montana. 00:08:29.000 --> 00:08:41.000 Libby amphibole asbestos or LAA is comprised of several amphibole minerals which were identified in the Rainy Creek Complex at the Libby, Montana vermiculite mine. 00:08:41.000 --> 00:08:46.000 The amphibole mixture that makes up LAA includes wind chite. 00:08:46.000 --> 00:08:51.000 Richterite, tribalite. Magnesio Rebecite. 00:08:51.000 --> 00:08:56.000 Magnesio arvetzanite. And edonite. 00:08:56.000 --> 00:09:04.000 Epa has developed separate toxological values for assessing risk posed by general asbestos and LAA. 00:09:04.000 --> 00:09:11.000 This is discussed later in the risk assessment recommendations section. 00:09:11.000 --> 00:09:17.000 The general term asbestos was applied to minerals with long flexible fibers. 00:09:17.000 --> 00:09:21.000 High tensile strength. Durability and heat resistance. 00:09:21.000 --> 00:09:33.000 Amphibles are also known for their acid and alkaline resistance. These properties make asbestos appealing for commercial use. 00:09:33.000 --> 00:09:42.000 Commercially, asbestos containing material or ACM, is any material containing greater than 1% asbestos. 00:09:42.000 --> 00:09:47.000 If any of the minerals we just reviewed in the geological perspective section. 00:09:47.000 --> 00:09:51.000 Are chemically altered, such as adding a binder to make a product. 00:09:51.000 --> 00:09:59.000 Then that product is considered ACM. Common types of ACM encountered at surplus sites include pipe insulation. 00:09:59.000 --> 00:10:04.000 Shingles and cement. 00:10:04.000 --> 00:10:13.000 Asbestos is analyzed by microscopy. The analytical method used will determine counting rules for asbestos analysis. 00:10:13.000 --> 00:10:18.000 Counting rules are used by microscopists During asbestos analysis. 00:10:18.000 --> 00:10:22.000 And will be discussed in more detail later in this training. 00:10:22.000 --> 00:10:32.000 For some analytical methods, a microscopist will identify what is seen under a microscope As asbestos by structure type, such as fibers and bundles. 00:10:32.000 --> 00:10:39.000 We'll record the length and width of each structure And we'll also identify the mineral type of each structure. 00:10:39.000 --> 00:10:48.000 The analytical method and or the defined counting rules will dictate what structures are considered asbestos. 00:10:48.000 --> 00:11:03.000 Different structure types, sizes, and mineral types may be excluded. The images on this slide are photographs of asbestos taken through a microscope. 00:11:03.000 --> 00:11:10.000 As you can see in these images. Multiple structures can be seen within the field of view of a microscope. 00:11:10.000 --> 00:11:17.000 During asbestos analysis. There could be mixtures of different particle sizes, structure types, and mineral types. 00:11:17.000 --> 00:11:23.000 The image on the left shows different structure types of tremolite, such as fibers and bundles. 00:11:23.000 --> 00:11:35.000 The image on the right shows an amyte fiber bundle. The brighter straight structure mixed with the curved chrysotile structures. 00:11:35.000 --> 00:11:48.000 Asbestos is a listed circular hazardous substance. Under 40 CFR, Part 302. Asbestos is also addressed by other statutes and regulations. 00:11:48.000 --> 00:11:56.000 Some examples include the Asbestos Hazard Emergency Response Act. Or ahira, which is under the Toxic Substances Control Act. 00:11:56.000 --> 00:12:05.000 Known as TSCA, the asbestos National Emission Standards for Hazardous Air Pollutants Or Nishap under the Clean Air Act. 00:12:05.000 --> 00:12:14.000 Osha General Industry and Construction Standards. In the asbestos maximum contaminant level, or MCL, Under the Clean Water Act. 00:12:14.000 --> 00:12:22.000 Note that different laws have different perspectives or definitions of asbestos. 00:12:22.000 --> 00:12:33.000 When discussing asbestos and the framework. The asbestos TRW states that asbestos is the generic name used for a group of naturally occurring mineral silicate fibers. 00:12:33.000 --> 00:12:42.000 Of the serpentine and amphibole series. Displaying similar physical characteristics Although differing in composition. 00:12:42.000 --> 00:12:52.000 It is a group of highly fibrous silicate minerals that readily separate into long thin strong fibers that have sufficient flexibility to be woven. 00:12:52.000 --> 00:13:06.000 Are heat resistant and chemically inert are electrical insulators and therefore are suitable for uses where incombustible non-conducting or chemically resistant materials are required. 00:13:06.000 --> 00:13:21.000 Description is intended to cover all mineral forms of asbestos that may be subject to circular authority and are associated with health effects in humans. 00:13:21.000 --> 00:13:27.000 Additionally, the framework may be useful For site assessment of other elongate mineral particles. 00:13:27.000 --> 00:13:33.000 Where health effects similar to asbestos such as mesothelioma have been indicated. 00:13:33.000 --> 00:13:39.000 Area night is one example of an elongate mineral particle that has been found on Superfund sites. 00:13:39.000 --> 00:13:46.000 The asbestos types that were just discussed on previous slides are typically magnesium silicates. 00:13:46.000 --> 00:13:50.000 Where Zeolites, like Arianite. Are aluminum silicates. 00:13:50.000 --> 00:13:57.000 Some properties of arionite, such as its chain-like structure. Are similar to the properties of asbestos. 00:13:57.000 --> 00:14:08.000 However, other properties, such as refractive index. Much different. Area night forms brittle, wool-like fibrous masses in the hollows of rock formations. 00:14:08.000 --> 00:14:13.000 For more information on Area Night or other elongate mineral particles. 00:14:13.000 --> 00:14:21.000 Please consult the framework and or the TRW Asbestos Committee. 00:14:21.000 --> 00:14:26.000 All right, ladies and gentlemen, we're going to take our first Q&A break at this time. 00:14:26.000 --> 00:14:32.000 And I'm going to ask some of my panelists to come on camera and I'll remind the live audience, if you have a question or comment. 00:14:32.000 --> 00:14:41.000 Go ahead and click the Q&A button at the bottom of your screen and you can type your message on in. I'm going to start reading through some of the questions that have already come into the Q&A. 00:14:41.000 --> 00:14:52.000 And this very first question, I'm going to take it and I might direct it at Joey because it gets into the structure of the course and what we may cover during this series. 00:14:52.000 --> 00:14:58.000 Is if we're going to discuss risk associated with exposure to asbestos in this class. 00:14:58.000 --> 00:15:04.000 Yeah, absolutely. We will be getting to that a little bit today and more on risk assessment tomorrow. So absolutely. 00:15:04.000 --> 00:15:18.000 Thank you. And so my next question Is asbestos used commercially in the US anymore? I thought it was banned decades ago. 00:15:18.000 --> 00:15:19.000 I can start this off. I know the main industry is the chloral alkali industry. 00:15:19.000 --> 00:15:24.000 Sure. 00:15:24.000 --> 00:15:41.000 So a group of plants for operating facilities Not many left, but around the US that they are the major consumer or user of asbestos. And that's mainly for gasket and the properties that are used. 00:15:41.000 --> 00:15:59.000 The high heat situations for chloralkali plants. But as far as commercially, if anyone else wants to jump in and talk a little bit about asbestos bands or That kind of stuff, feel free. 00:15:59.000 --> 00:16:03.000 Yeah, sure. It hasn't been fully banned in the United States just yet. 00:16:03.000 --> 00:16:20.000 And while we're still talking about it is from its use in building materials that have been around for many years. I think the thought was that it would have been fully removed from those buildings at this point, but that was not the case. 00:16:20.000 --> 00:16:28.000 So we're still dealing with it. At EPA from buildings that are improperly torn down and spread asbestos around. 00:16:28.000 --> 00:16:37.000 And in the case of Libby, we've learned that damaging are moving naturally occurring asbestos. 00:16:37.000 --> 00:16:41.000 In its geologic setting can also be harmful. 00:16:41.000 --> 00:16:54.000 So that's, I guess, sort of the context of why we're still talking about it, even though it's been largely disused in building materials. 00:16:54.000 --> 00:16:55.000 Okay. 00:16:55.000 --> 00:17:09.000 And to add to what Tim has said. Vermiculite or from vermic or from the Libby mine has been or was used extensively for home insulation. 00:17:09.000 --> 00:17:15.000 So there are a number of homes throughout the United States. 00:17:15.000 --> 00:17:19.000 That still have vermiculite attic insulation. 00:17:19.000 --> 00:17:31.000 And if that is encountered. One should contact a qualified asbestos removal firm. 00:17:31.000 --> 00:17:39.000 To address the issue. Of attic insulation. 00:17:39.000 --> 00:17:46.000 Okay. Anyone else want to chime in? 00:17:46.000 --> 00:17:54.000 Okay, I'm going to move on to our next question. And this one is asking because we talked about all the different types of asbestos in the presentation so far. 00:17:54.000 --> 00:18:13.000 So some of the participants are wondering if cleanup varies by the type of asbestos, or is it pretty much the same approach regardless of which form you're dealing with? 00:18:13.000 --> 00:18:14.000 And I may pick, there we go, Joey. It's like, I'll start with you. 00:18:14.000 --> 00:18:22.000 I'm not shy. And I say, I'll start it off. There are commonalities in asbestos cleanups. 00:18:22.000 --> 00:18:29.000 Things like our work practices, our decon techniques. Even our disposal practices. 00:18:29.000 --> 00:18:44.000 Are going to be very, very similar. No matter what the type is. I'll let others join in here, but I believe Sometimes the characterization, so things like sampling and figuring out just where your area of concern is going to maybe depend on the type of asbestos. 00:18:44.000 --> 00:18:57.000 Anyone want to add to differences in cleanup approaches based on asbestos type. 00:18:57.000 --> 00:18:58.000 Well, I think you've encapsulated it there. So thank you joke Appreciate it. 00:18:58.000 --> 00:19:06.000 Yeah. I'm sure there are nuances as well as, and we'll get into it, especially when it comes to analysis as well. 00:19:06.000 --> 00:19:11.000 Depending on what type of asbestos you have. So we will talk about that part as well later. 00:19:11.000 --> 00:19:31.000 Excellent. We have one more question in the queue that I'll take now. And this is in the form of who should I call Does the state get to call EPA or someone else? Who do I call if I think I've encountered asbestos at a site? 00:19:31.000 --> 00:19:39.000 Yeah, I guess that depends on the state that you're in and the asbestos that you're encountering. 00:19:39.000 --> 00:19:53.000 Most states have delegated programs to enforce asbestos regulations like in buildings in particular So in those cases, those states would be your first point of contact. 00:19:53.000 --> 00:20:07.000 If you're at a Superfund site or something like that where the damage has been done and things are spread around or you're encountering naturally occurring asbestos. 00:20:07.000 --> 00:20:20.000 Possibly EPA would be your your line of… contact your first point of contact but in general You know, the states have that. 00:20:20.000 --> 00:20:24.000 Enforcement authority to go after folks. 00:20:24.000 --> 00:20:39.000 In the Superfund program, things are a little bit different in the types of asbestos that we deal with, but I'd say generally speaking, the states Joey, do you have… When would OSCs be called? 00:20:39.000 --> 00:20:42.000 As a first point of contact. 00:20:42.000 --> 00:21:00.000 Yeah, we need to have a release. Of a hazardous substance, which asbestos is. That was one of the slides into the environment, right? So we can't go after stuff that is part of a building structure, stuff that is Not friable. We'll talk about the definition of friable versus friable. 00:21:00.000 --> 00:21:07.000 But just getting back to this general question, if you are stuck You're not getting an answer from a state or maybe from a local counterpart. 00:21:07.000 --> 00:21:22.000 That's what we are here for, the TRW. You can always reach out and email the asbestos TR&W, we can do a little digging or maybe reach to some of our contacts, whether it's on a state level, local level. 00:21:22.000 --> 00:21:27.000 Okay, and then just a quick clarification. So Joey, if a building is being demolished. 00:21:27.000 --> 00:21:34.000 And they're saying it's release or mobilize that asbestos. It is no longer contained in a structure. 00:21:34.000 --> 00:21:35.000 Is that when EPA could or an OSC could be brought on board? 00:21:35.000 --> 00:21:45.000 Yeah. They can be notified. I would probably call the National Response Center, which is the 800 number to report a release. 00:21:45.000 --> 00:21:57.000 You're going to get likely a more on the ground response. I'm not going to say quicker but If you reach to a state program. So if you just look up your state's environmental program. 00:21:57.000 --> 00:22:11.000 And see, you know, I'm sitting here in region three, so I know Pennsylvania's got a a page right for a page for their asbestos programs and for the release and that kind of stuff and as well as enforcement. 00:22:11.000 --> 00:22:24.000 Osc is an on-scene coordinator, so we're the emergency responders, Colin and i that are on this call are both OSCs for quicker time critical responses. 00:22:24.000 --> 00:22:37.000 All right. Well, at this time, I think we have cleared through the question queues. I think we'll carry on with the presentation. But I want to thank our panelists. They will stay with us. We're going to go through another module here and pause again for a Q&A break. 00:22:37.000 --> 00:22:47.000 I will encourage the audience to continue to submit your questions and comments. So if there's a term, an acronym, a link, a reference, anything that you have a question about, feel free to type that into the Q&A at any time. 00:22:47.000 --> 00:22:55.000 And we'll pause again here in just a moment for another Q&A break. 00:22:55.000 --> 00:23:01.000 The asbestos framework emphasizes an empirical approach to site investigation and characterization. 00:23:01.000 --> 00:23:13.000 Specifically, a combination of samples from media such as air and soil, are recommended to characterize exposures for risk assessment and nature and extent of the contamination. 00:23:13.000 --> 00:23:23.000 The framework provides recommendations for sampling asbestos in soil. Settled dust and air. 00:23:23.000 --> 00:23:34.000 The framework recommends incremental sampling methodology. Or ISM to collect soil samples that are as representative of the sampled areas as possible. 00:23:34.000 --> 00:23:45.000 Because of the inherent heterogeneity of asbestos in soil. Collecting 30 to 100 increments per composite is recommended by the asbestos TRW. 00:23:45.000 --> 00:23:56.000 More increments would provide a more reliable estimate. The potential for subsurface presence Upward migration or future land uses. 00:23:56.000 --> 00:24:05.000 Involving soil excavation. Determines if subsurface asbestos should also be considered in addition to surface samples. 00:24:05.000 --> 00:24:13.000 Careful consideration should also be given to whether sample processing steps should be conducted in the field or in the lab. 00:24:13.000 --> 00:24:19.000 Rigorous and well-considered sample processing is an integral part of ISM. 00:24:19.000 --> 00:24:25.000 The asbestos content of soil is usually low compared to bulk asbestos containing materials. 00:24:25.000 --> 00:24:33.000 So the fraction of particles that are asbestos is small An accurate quantification is very difficult. 00:24:33.000 --> 00:24:40.000 Thus, soil results should generally be interpreted semi-quantitatively. During initial phases of a site assessment. 00:24:40.000 --> 00:24:48.000 And cannot therefore be used for risk assessment. Air sample results are required for risk assessment. 00:24:48.000 --> 00:24:58.000 These and other considerations for soil sampling are discussed in more detail In the next section, starting with slide 34. 00:24:58.000 --> 00:25:01.000 So our results do allow for initial findings that a release has occurred. 00:25:01.000 --> 00:25:08.000 And may help to focus future sampling actions. 00:25:08.000 --> 00:25:14.000 Ism is a composite sampling and processing protocol. That reduces data variability. 00:25:14.000 --> 00:25:20.000 And provides a reasonably unbiased estimate of contaminant concentrations in soil. 00:25:20.000 --> 00:25:28.000 The ISM process includes collecting 30 to 100 increments that are then combined, processed. 00:25:28.000 --> 00:25:40.000 And subsampled according to specific protocols. The Interstate Technology and Regulatory Council Where ITRC provides ISM guidance at the website listed on this slide. 00:25:40.000 --> 00:25:47.000 It can also be accessed using this QR code. 00:25:47.000 --> 00:25:56.000 Dust samples may be collected on solid non-porous surfaces. To identify areas where asbestos is present or absent. 00:25:56.000 --> 00:26:05.000 Currently, there is insufficient information to correlate asbestos content in dust with human exposure to be used in risk assessments at circler sites. 00:26:05.000 --> 00:26:10.000 However, dust information may be used to support risk management actions. 00:26:10.000 --> 00:26:16.000 When exterior, high-level sources are present. That result in high indoor dust levels. 00:26:16.000 --> 00:26:24.000 As with soil sampling, air sample results are required for risk assessment, where asbestos is suspected in indoor dust. 00:26:24.000 --> 00:26:30.000 Two sample collection methods are available for Dust. Micro vacuum and wipe sampling. 00:26:30.000 --> 00:26:44.000 The microvacuum approach, shown on this slide. Is the most commonly used to support indoor investigations And, in general, is the recommended method for sampling dust in indoor environments for asbestos. 00:26:44.000 --> 00:26:49.000 A low suction vacuum captures dust and fibers on a filter cassette. 00:26:49.000 --> 00:26:58.000 Astm D5755 is a standard test method for microvacuum sampling An analysis of asbestos and dust. 00:26:58.000 --> 00:27:07.000 It provides a fiber loading per surface area in units of structures per square centimeter. 00:27:07.000 --> 00:27:14.000 Wipe sampling is an alternative method for dust that may be considered on a site-specific basis. 00:27:14.000 --> 00:27:28.000 Astm D6480-19 is the standard test method or wipe sampling of surfaces, an analysis of asbestos, structures by transmission electron microscopy. 00:27:28.000 --> 00:27:32.000 For this method, a known area of a surface is wiped with a cloth material. 00:27:32.000 --> 00:27:45.000 To collect a sample. Dust results from both microvacuum and wipe sampling are typically compared to a screening level of 5,000 total structures per square centimeter. 00:27:45.000 --> 00:27:54.000 This screening benchmark was used at the World Trade Center and Libby, Montana sites. 00:27:54.000 --> 00:28:01.000 Air sampling is used for regulatory compliance. Environmental condition assessment, and human exposure assessment. 00:28:01.000 --> 00:28:06.000 Air sampling should be performed in the breathing zone if used for risk evaluation. 00:28:06.000 --> 00:28:13.000 Activity-based sampling, or ABS, is the recommended sampling method for human health risk assessment. 00:28:13.000 --> 00:28:20.000 Abs should be performed while conducting a dust generating activity Typical for the site, like raking. 00:28:20.000 --> 00:28:30.000 Jogging, and gardening. Passive air samples may not reflect potential exposure of activities that disturb soil. 00:28:30.000 --> 00:28:35.000 Additional information is contained in Appendix E of the 2021 Framework. 00:28:35.000 --> 00:28:47.000 This is an ERT Helpful Hint. For ABS document, which can be accessed either in the framework or at the link on this slide. 00:28:47.000 --> 00:28:55.000 Why activity-based sampling? As shown in this figure, fiber is located in indoor and outdoor environments. 00:28:55.000 --> 00:29:00.000 Such as those entrained in a carpet indoors are mixed with soils outdoors. 00:29:00.000 --> 00:29:09.000 Can be mobilized and released into air when disturbed. We are interested in capturing the fibers in the breathing zone for human health risk assessment. 00:29:09.000 --> 00:29:15.000 Because air concentrations cannot currently be calculated using soil and dust concentrations. 00:29:15.000 --> 00:29:31.000 Air sampling is required for risk assessment The resuspension of particulates, including fibers from human activity during ABS, produces a personal cloud that can be sampled as breathing zone air for risk evaluation. 00:29:31.000 --> 00:29:36.000 Site-specific factors such as nature and the type of asbestos material. 00:29:36.000 --> 00:29:47.000 Soil properties, weather, and the level and type of disturbance all impact what can get into the air. 00:29:47.000 --> 00:30:13.000 In addition, asbestos is not uniformly distributed in soil. Soil concentrations less than 1% have been demonstrated to represent significant risk when disturbed. Using 1% as a screening benchmark is not health As you can see in these photos, soil can hide a lot of asbestos. 00:30:13.000 --> 00:30:20.000 Activity-based outdoor sampling uses an activity that produces a high-end soil disturbance. 00:30:20.000 --> 00:30:36.000 The raking scenario is the recommended high-end outdoor activity. The image shows a sampler raking While wearing the appropriate PPE, For a specified time over an area of concern. 00:30:36.000 --> 00:30:43.000 An area of concern could be broken out into grids. Or decision units depending on the size. 00:30:43.000 --> 00:30:49.000 Personal air samples from the breathing zone are collected during the activity. 00:30:49.000 --> 00:30:55.000 In this photo, the backpack the sampler is wearing contains the sampling equipment. 00:30:55.000 --> 00:31:02.000 Once analyzed, the sample provides a site-specific measure of fiber release from soil. 00:31:02.000 --> 00:31:12.000 The concentration of asbestos in the breathing zone that results from the activity In this case, raking. 00:31:12.000 --> 00:31:20.000 Abs scenarios should be typical high-end activities Representative of current or future use at the site. 00:31:20.000 --> 00:31:29.000 The generic ABS scenario is raking with a leaf rake. Other examples of ABS scenarios include rototilling. 00:31:29.000 --> 00:31:34.000 A child playing in the dirt. Lawn mowing, bicycling, jogging. 00:31:34.000 --> 00:31:39.000 Playing soccer, driving. Atv writing, digging. 00:31:39.000 --> 00:31:47.000 Weed whacking, walking with a stroller. Playing basketball, hiking, motorcycling, and gardening. 00:31:47.000 --> 00:31:54.000 The following slides will show photos of different ABS scenarios that have been used in the past. 00:31:54.000 --> 00:32:02.000 Work with a risk assessor to select an ABS activity that represents high-end exposure for your site. 00:32:02.000 --> 00:32:07.000 For additional information on ABS, Refer to Appendix E of the EPA framework. 00:32:07.000 --> 00:32:19.000 Which is ERT's Helpful Hints for ABS Sampling. An EPA ERT SOP 2084. 00:32:19.000 --> 00:32:26.000 Working slash occupational scenarios include raking. 00:32:26.000 --> 00:32:31.000 Digging. 00:32:31.000 --> 00:32:36.000 Lawn mowing. 00:32:36.000 --> 00:32:41.000 Weed whacking. 00:32:41.000 --> 00:32:47.000 And rototilling. 00:32:47.000 --> 00:32:52.000 Recreational scenarios include walking with a stroller. 00:32:52.000 --> 00:33:02.000 Note that the breathing zone for this scenario is both inside of the stroller and close to the face of the adult pushing the stroller. 00:33:02.000 --> 00:33:16.000 Atv writing, note that it is important to have two vehicles participate in this activity As the dust and particulate exposure is greater for the trailing vehicle. 00:33:16.000 --> 00:33:26.000 Bike riding. Again, multiple bikes are needed to adequately assess exposure to the trailing bikes. 00:33:26.000 --> 00:33:40.000 Hiking, note that two air sampling cassettes or sampling points are placed on one sampler to measure the breathing zone for both an adult and child hiker 00:33:40.000 --> 00:33:46.000 Playing soccer. 00:33:46.000 --> 00:33:57.000 Driving on an unpaved road Again, multiple vehicles should be used to assess exposure for the trailing vehicle. 00:33:57.000 --> 00:34:08.000 Child playing in the dirt with a shovel and bucket. Note that the error sampling cassette or sampling point is lower or closer to the bucket than the adult breathing zone. 00:34:08.000 --> 00:34:14.000 As this scenario is meant to be representative of a child. 00:34:14.000 --> 00:34:19.000 Activity-based indoor sampling scenarios may include the use of fans. 00:34:19.000 --> 00:34:27.000 Leaf blowers, and brooms. Air samples are collected from the breathing zone as well as perimeter air samples. 00:34:27.000 --> 00:34:36.000 Sample results provide a quantitative concentration of fibers in air resulting from dust disturbance. 00:34:36.000 --> 00:34:50.000 Some key points about ABS and air sampling include, one. Measurements made directly from the breathing zone are the most valuable Two, ABS is the most reliable estimate of exposure. 00:34:50.000 --> 00:34:59.000 Three, dust measurements and or solid media data For example, soil or soil ACM, etc. 00:34:59.000 --> 00:35:03.000 Cannot currently be converted to air concentration data for risk assessment. 00:35:03.000 --> 00:35:08.000 Dust sample results may be used to support risk management decisions. 00:35:08.000 --> 00:35:22.000 See slide 24. And four, measurements from stationary air monitors may not provide reliable estimates of human inhalation exposure. 00:35:22.000 --> 00:35:34.000 The link and QR code on this slide are for a video that covers an overview and considerations for ABS sampling. 00:35:34.000 --> 00:35:41.000 All right. At this time, I'm going to go ahead and pull up a video and play that for everyone. 00:35:41.000 --> 00:35:44.000 So bear with me while I call that up and move it over to the screen. 00:35:44.000 --> 00:35:52.000 If… If you encounter any technical difficulties in watching the video here. 00:35:52.000 --> 00:36:11.000 Through Zoom, we do recognize that it sometimes periodically doesn't play back with the best quality. I'm going to place a link to this video directly as well in the chat so you can play it back locally. 00:36:11.000 --> 00:36:34.000 The 2021 Framework for Investigating Asbestos Contaminated Circlisites provides remedial and removal managers, remedial project managers, on-scene coordinators, site assessors, and other decision makers with information to assist in the evaluation of asbestos risks at Circlisites. This video guides site managers 00:36:34.000 --> 00:36:43.000 Through the process of collecting samples, such as soil, dust, and air, and describes activity-based sampling procedures, or ABS. 00:36:43.000 --> 00:36:52.000 Including area selection. Grid market, perimeter and background sampling, various ABS scenarios, and considerations for site cleanup. 00:36:52.000 --> 00:37:15.000 Performing ABS is included in steps four and five. Of the asbestos decision framework for outdoor and indoor environments. As included in the 2021 Framework for investigating asbestos Contaminated circle sites. 00:37:15.000 --> 00:37:27.000 Keep the area selected for ABS sampling relatively level and free of any standing water or excess trip hazards. 00:37:27.000 --> 00:37:38.000 Areas with thick vegetation should be trimmed. Remove plastic sheeting from grids and soil and allow sufficient time for drying. 00:37:38.000 --> 00:38:02.000 Clearly define the grid area with high visibility markings. Mark sampling activities including grid corners with a GPS receiver coupled with an application such as field maps. 00:38:02.000 --> 00:38:16.000 Established decision units for the site using a GIS software. Once decision units are established, determine the sample design to be implemented. Typical sample designs include composite sampling. 00:38:16.000 --> 00:38:25.000 Discrete sampling. And the recommended method of the incremental sampling methodology. 00:38:25.000 --> 00:38:47.000 Following the sample design selected, use a scoop or trowel To collect the required number of surface samples. Label each homogenized sample for delivery to the lab. 00:38:47.000 --> 00:39:00.000 The 2021 framework provides additional details related to soil sample analysis. A common method employed includes polarized light microscopy, or PLM. 00:39:00.000 --> 00:39:17.000 However, sampling at multiple sites has shown that even when soils are non-detected by PLM, with a reporting limit of less than 0.25% concentrations of asbestos in the air via ABS may result in unacceptable health risks. 00:39:17.000 --> 00:39:26.000 Therefore, although soil samples exceeding 0.25% asbestos can be used to make a determination to clean up a grid. 00:39:26.000 --> 00:39:34.000 Abs is recommended to rule out risk concerns in grids with trace or even non-detect results in soil. 00:39:34.000 --> 00:40:04.000 To ensure risk thresholds are not exceeded when the material is disturbed. The following table shows an instance where soil data analyzed by PLM indicated non-detect and trace results. While ABS employed in the same sampling grids identified more substantial results. 00:40:05.000 --> 00:40:10.000 Perform ABS in as dry as possible conditions for the worst case scenario. 00:40:10.000 --> 00:40:16.000 Collect soil moisture readings from at least 10 locations within the ABS grid. 00:40:16.000 --> 00:40:32.000 A soil moisture reading of 10% or less is recommended to capture optimum contaminant release. 00:40:32.000 --> 00:40:48.000 Interior air sampling for asbestos requires a tripod. Sample pump, tubing, a calibration unit, and appropriate sample media For the analytical method, select it. 00:40:48.000 --> 00:40:53.000 Calibrate the sample pumps to the required flow rate for the analytical method selected. 00:40:53.000 --> 00:41:13.000 And place sample media within the breathing zone. Interior samples are typically collected in a representative functional space from within the structure. 00:41:13.000 --> 00:41:26.000 Collect indoor dust samples on solid, non-porous surfaces to determine where asbestos may be present. The preferred method for dust sample collection includes the microvacuum method. 00:41:26.000 --> 00:41:32.000 This method typically requires a sample template, typically 10 centimeters by 10 centimeters. 00:41:32.000 --> 00:41:43.000 A calibrated personal sampling pump and sampling cassettes with a one to two inch piece of tubing are cut to a 45 degree angle to allow micro vacuum sampling. 00:41:43.000 --> 00:41:51.000 Vacuum the area within the template using a consistent back and forth motion, covering the template area for the required duration. 00:41:51.000 --> 00:42:00.000 Dust sampling can also be conducted with the wipe method. This method is similar to the microvac method but requires no specialized equipment. In this method. 00:42:00.000 --> 00:42:09.000 Wipe the template using the laboratory supplied wipe that is folded to allow for a clean section for each direction wiped in the template. 00:42:09.000 --> 00:42:17.000 Note that dust sampling is similar to soil sampling, in that the type of data obtained is not considered suitable for risk assessment. 00:42:17.000 --> 00:42:32.000 To quantitatively evaluate risk. Indoor air samples are necessary. 00:42:32.000 --> 00:42:50.000 Determine data quality objectives and the risk-based levels of concern Prior to conducting ABS sampling. This allows the project team to ensure that the analytical results will be at or below the risk-based level of concern, which is necessary for evaluating risk and making decisions. 00:42:50.000 --> 00:43:05.000 The appropriate sample volume and flow rate should be determined prior to sampling as well. The EPA grid opening calculator can be used to calculate sample volume and flow rate based on a specified risk-based level of concern. 00:43:05.000 --> 00:43:30.000 Additional information concerning data quality objectives, data management, and establishing levels of concern can be found in the 2021 Framework for Investigating Asbestos Contaminated surplus Sites 00:43:30.000 --> 00:43:42.000 Select perimeter and background sampling locations prior to beginning ABS. Base this decision on grid location and current wind conditions. During the ABS activity event. 00:43:42.000 --> 00:43:48.000 Power sources can include generators. Although there are battery-powered options as well. 00:43:48.000 --> 00:43:54.000 Once locations are determined, set up the sample station, install sample media. 00:43:54.000 --> 00:44:13.000 And calibrate the sample pumps. Log sample media and pump calibration data into field application software. 00:44:13.000 --> 00:44:19.000 Collect personal samples for ABS to properly categorize the levels of airborne asbestos exposures. 00:44:19.000 --> 00:44:26.000 Abs sampling requires a backpack modified to hold a low flow and high flow sample pump. 00:44:26.000 --> 00:44:34.000 With sample cassettes attached. Calibrate each sample pump to a predetermined flow rate. To meet analytical sensitivity requirements. 00:44:34.000 --> 00:44:55.000 Before sampling begins. Secure the sample media to the backpack following calibration. The following image is a typical example of a low flow and high flow sample pump within a backpack. 00:44:55.000 --> 00:45:08.000 Place the apparatus containing the sample pumps and sample media on the participant after they equip PPE. 00:45:08.000 --> 00:45:20.000 Remove caps on sample cassettes. Start the sample pumps and have the participant begin ABS sampling activities. 00:45:20.000 --> 00:45:33.000 Here we see the raking scenario. Each ABS scenario lasts approximately one hour. Rotate participants every 15 to 30 minutes to reduce heat exposure. 00:45:33.000 --> 00:45:41.000 It is important to frequently check sample pumps throughout the sampling period to make sure they are not overloaded and are operating as intended. 00:45:41.000 --> 00:45:51.000 Several site-specific ABS scenarios are available. Here we see a walker with stroller. 00:45:51.000 --> 00:46:13.000 Elite and trailing bicycle. An example of a child playing in dirt scenarios. 00:46:13.000 --> 00:46:39.000 Abs sampling may also be used indoors to characterize risk. Examples of indoor ABS activities include Sweeping, vacuuming, or simulating other activities that may disturb indoor dust. 00:46:39.000 --> 00:46:45.000 Once the ABS scenario is complete, remove the sampling apparatus from the participant. 00:46:45.000 --> 00:47:00.000 Turn off both sample pumps and cap each sample cassette. 00:47:00.000 --> 00:47:12.000 Use a wet wipe to decontaminate equipment and record the final flow rates to allow for calculation of the average flow rate during the sample event. 00:47:12.000 --> 00:47:32.000 Collect samples from the perimeter and background locations. Check flow rates and enter data into field application software. 00:47:32.000 --> 00:47:46.000 Asbestos may be released when soil is disturbed during response activities. Project managers should ensure that dust suppression is used Including spraying with water to minimize dust being generated during site activities. 00:47:46.000 --> 00:48:01.000 Abs can also be used for grid clearance to ensure that contamination does not remain at the site after an action is performed. 00:48:01.000 --> 00:48:09.000 All right. So I'm going to change our view here and call the presentation content back up on the screen. 00:48:09.000 --> 00:48:19.000 And then as I do that, let me click forward here and just call my panelists to come back on camera because we are going to jump into our next Q&A break. 00:48:19.000 --> 00:48:29.000 So I will remind the audience, if you have questions or comments, you can use the Q&A to submit those in privately. We're going to start reading through some of these questions that have come in. 00:48:29.000 --> 00:48:40.000 As the panelists come on camera. So the very first set of questions that I have came in earlier at the beginning of this section, getting into the sampling methodology. 00:48:40.000 --> 00:48:45.000 So this first question wanted to know how exactly does one determine the number of composites? 00:48:45.000 --> 00:48:47.000 When you're sampling. 00:48:47.000 --> 00:49:00.000 Yeah, that's a good question. And we have been doing some research Several of us here on the tr To answer that question, and it looks like the answer is more is better. 00:49:00.000 --> 00:49:14.000 Asbestos in soil is very heterogeneous. You can sample collect samples side by side and get wildly different answers. So the more increments that you use to build your sample. 00:49:14.000 --> 00:49:20.000 The more representative we have found that sample is, and more importantly, the more reproducible it is. 00:49:20.000 --> 00:49:37.000 So if you're looking on that scale of 30 to 100, 100, is where i would land, it's a little more labor intensive. The ITRC guidance calls out a minimum of 30 increments to build your samples, but we've found that 00:49:37.000 --> 00:49:52.000 While that minimum is good for things like metals, it's really not well suited to asbestos. So I would go higher and you know would shoot for close to 100 00:49:52.000 --> 00:50:02.000 Okay. All right. Excellent. And a related question. For soils, how many square feet per sample? 00:50:02.000 --> 00:50:13.000 That's… we don't have a good answer to that. That's going to depend on where you think your asbestos is, how it was released. 00:50:13.000 --> 00:50:24.000 How broadly it might have been spread at your setting. So it's going to be site specific. There's not a good general answer to that question. 00:50:24.000 --> 00:50:34.000 If you're using incremental sampling, as we're discussing. Then you would be using what ITRC calls decision units. 00:50:34.000 --> 00:50:42.000 And those would be based on, again, releases suspected data that you have in hand and other things. 00:50:42.000 --> 00:51:07.000 Generally, you know, we're generally you know we would be collecting those hundred increments across that decision unit. So hopefully that answers your question there but You know, we wouldn't we Typically, we've tried to get away from collecting discrete samples in a grid or otherwise at our sites is just being 00:51:07.000 --> 00:51:11.000 Not representative of the underlying soil. 00:51:11.000 --> 00:51:17.000 Okay. 00:51:17.000 --> 00:51:18.000 Mm-hmm. 00:51:18.000 --> 00:51:29.000 And a decision unit could be as small as, say, a backyard garden or it could be as large as a football field It just depends on on who the receptors might be. 00:51:29.000 --> 00:51:35.000 Uh… other site conditions such as that. 00:51:35.000 --> 00:51:36.000 Okay. 00:51:36.000 --> 00:51:46.000 I'm going to chime in for the lab folks. You want to check with the lab on the total volume of the sample that you're going to submit for analysis, though. 00:51:46.000 --> 00:51:53.000 Make sure that you're not sending them You know, several five gallon buckets worth 00:51:53.000 --> 00:52:12.000 That yeah that is a good… point to the, and I think that came up in one of the slides is If you're collecting incremental samples, 100 increments is going to be close to a five kilogram sample. Jed and his lab might not be too excited to receive 00:52:12.000 --> 00:52:25.000 Five kilograms of contaminated dirt. So you may have to do some soil processing to sub sample Before you send that to the lab. So work closely with your lab on who's going to do that soil processing and where 00:52:25.000 --> 00:52:34.000 And… also incremental sampling. You may collect a certain number of increments in the field when they get to the lab. 00:52:34.000 --> 00:52:42.000 We also will spread that out on a sheet and then redo the increments again to adjust the volume so that that's occurring as well. 00:52:42.000 --> 00:52:48.000 Yeah. 00:52:48.000 --> 00:52:59.000 Right. And that's, again, something that you want to discuss with your lab ahead of time. They may not be super excited to have five kilograms of asbestos contaminated soil spread out. 00:52:59.000 --> 00:53:10.000 And a pan in their lap or they may not be equipped to do that. So you may have to do it in the field Which is something that we have done that sub sampling before sending it off to the lab. 00:53:10.000 --> 00:53:21.000 Okay. And I see some additional questions about ISM. I'm going to take one more and then I'm going to move to another grouping of questions that we have. We may come back to some of these later as time permits. 00:53:21.000 --> 00:53:35.000 But there was an observation simply made that ISM can be expensive and labor intensive. So they're just wondering if you can offer some thoughts if it's really necessary when you're doing soil sampling for asbestos. 00:53:35.000 --> 00:53:41.000 Necessary is a loaded… term, right? 00:53:41.000 --> 00:53:49.000 It can be especially labor intensive when you're in PPE to collect these samples. 00:53:49.000 --> 00:53:59.000 But yeah, I will say that the data that you're going to get from those incremental samples is going to be better than collecting discrete samples. 00:53:59.000 --> 00:54:04.000 So… Depending on your site conditions. 00:54:04.000 --> 00:54:19.000 If you've got percent levels in discrete samples, you probably don't need incremental samples to make site decisions, right? You're going to know that you have elevated concentrations and you can take an action. 00:54:19.000 --> 00:54:22.000 And the framework is intended to be dynamic in that way. 00:54:22.000 --> 00:54:30.000 That if you have a clear cause to go forward. Doing ABS may not be necessary. 00:54:30.000 --> 00:54:37.000 If you see if you've lots of asbestos in soil, that may be all that you need to do to take your action. 00:54:37.000 --> 00:54:46.000 So it's going to be site specific. We just recommend it as a TRW to collect ISM because it gives us better data. 00:54:46.000 --> 00:54:53.000 But it may not be necessary. Air quotes in all cases. 00:54:53.000 --> 00:55:00.000 All right, excellent. I'm going to move on to some questions about dust sampling. 00:55:00.000 --> 00:55:08.000 So this first one is asking, would you assume dust is contaminated if it's observed in the vicinity of damaged insulation, so friable material? 00:55:08.000 --> 00:55:22.000 Or has damaged materials commingled with the dust. Or is there an option to sample out the dust via wipe air bulk sampling? 00:55:22.000 --> 00:55:34.000 I would want analysis on that damaged insulation first. Not just a visual viable insulation next to it but It's a problem. 00:55:34.000 --> 00:55:43.000 You guys can add to it, but it's an additional line of evidence having that dust sample To go along with your bulk sampling. 00:55:43.000 --> 00:55:56.000 And that's usually how we use the dust and wipe samples for additional lines of evidence from something either outside making it inside or outside something inside being friable and causing release inside. 00:55:56.000 --> 00:55:57.000 Okay. 00:55:57.000 --> 00:56:10.000 Yeah, I would just also add, I mean, if there's a especially sensitive receptor, a dust sample could be that extra insurance, like Joey mentioned We have a case study tomorrow. 00:56:10.000 --> 00:56:30.000 Involving a… daycare next to a a building that was damaged that contained asbestos and they did some dust sampling in that daycare to help confirm to the parents and to the teachers that the asbestos to not make its way into the building but 00:56:30.000 --> 00:56:36.000 Like Joey said, the bulk sampling is what you really want to get. 00:56:36.000 --> 00:56:47.000 All right, excellent. And a point of clarification. So one attendee wanted to know why can't soil results be used for risk assessment? 00:56:47.000 --> 00:56:52.000 I think we all have a pretty solid response on this one. 00:56:52.000 --> 00:57:05.000 But I just go that the whole reason you just sat through a 10 minute video on activity-based sampling And why we want to disturb the media, including soil. 00:57:05.000 --> 00:57:22.000 Or sediment or anything that that we could disturb is because it's been demonstrated through pilot studies and sampling experiments, if you want to call them that that 1% of acm or greater. 00:57:22.000 --> 00:57:30.000 Guideline for something being considered asbestos, ACM, asbestos containing material is not protective. 00:57:30.000 --> 00:57:36.000 And it requires a disturbance. And we do that through the scenarios. 00:57:36.000 --> 00:57:53.000 So I think the one, I'm sorry if I'm rambling here but The one case study I remember during this 2004 was the mike cook memo epa memo about this but It showed a bunch of samples collected at about 0.25% soil asbestos and soil. 00:57:53.000 --> 00:57:59.000 And upon disturbing and collecting air samples related to that sample population. 00:57:59.000 --> 00:58:10.000 The levels were losing a risk. I jumbled that all around. So feel free to Give me a little correction there, guys. 00:58:10.000 --> 00:58:19.000 I think you've hit it spot on is that the more complicated answers that the soil doesn't give us air concentrations. 00:58:19.000 --> 00:58:26.000 Our toxicity data for risk assessment is based on inhalation. So we need that concentration in air. 00:58:26.000 --> 00:58:33.000 To do that. We don't have a good method for extrapolating soil concentrations to air. 00:58:33.000 --> 00:58:50.000 And as Joey pointed out. In other kinds of asbestos happening, what seems to be okay getting non-detects or very low concentrations of When disturbed have created air concentrations that present an unacceptable risk. 00:58:50.000 --> 00:58:54.000 So that's really the take home. Of the framework. 00:58:54.000 --> 00:58:59.000 Is that we need to, we're doing all these things to understand the concentration in air. 00:58:59.000 --> 00:59:09.000 That people can be exposed to. And we can use our toxicity information that's based on inhalation In order to do the risk assessment. 00:59:09.000 --> 00:59:17.000 Okay. And could you confirm for another participant about those indoor dust measurements? If you can't use those for risk assessment. 00:59:17.000 --> 00:59:25.000 Then are we sampling just to confirm presence or absence? Of asbestos? 00:59:25.000 --> 00:59:37.000 That's part of it. But again, if we are finding very high concentrations in that dust that can give us an indication that we need to take an action. 00:59:37.000 --> 00:59:54.000 And we wouldn't need to do like indoor ABS there to confirm that so It can serve that purpose to show that there's been a release. It can help us to decide to take an action and waive doing the ABS. So there's several reasons for doing it. 00:59:54.000 --> 01:00:03.000 And also puts together as someone earlier talked about lines of evidence of showing that the lease releases occurred or asbestos from outside has baited inside. 01:00:03.000 --> 01:00:08.000 Those types of things. So I think we have covered that fairly. 01:00:08.000 --> 01:00:21.000 Okay. Can you confirm, does the ABS, the activity-based sampling, include multiple scenarios, raking and lawn mowing? 01:00:21.000 --> 01:00:29.000 It can contain or include multiple scenarios depending on the site-specific. 01:00:29.000 --> 01:00:40.000 Conditions and the conditions and potential receptors that you might be you know that might encounter the site. 01:00:40.000 --> 01:01:05.000 You know, you could have a scenario for mowing a yard uh and uh by a resident and if there's a small garden that gardening might be another exposure scenario that one would need to evaluate. 01:01:05.000 --> 01:01:11.000 So you can have multiple ABS scenarios. 01:01:11.000 --> 01:01:20.000 Depending on site conditions and the receptor population that's involved. 01:01:20.000 --> 01:01:32.000 Okay. A quick question on what we might cover later on in the training. Are we going to look at how to sample materials that are suspected of containing asbestos, like insulation, fireproof drywall? 01:01:32.000 --> 01:01:37.000 And then once that's sampled, what your evaluation criteria would be? 01:01:37.000 --> 01:01:48.000 No. And the reason for that is that there's lots of guidance OSHA guidance, EPA guidance, and then niche apps and AHIRA that cover all that. 01:01:48.000 --> 01:01:58.000 Our primary focus here is on… the asbestos the framework for investigating asbestos contaminated Superfund sites. 01:01:58.000 --> 01:02:03.000 Which kind of goes beyond that that general what I call, you know. 01:02:03.000 --> 01:02:09.000 Everyday asbestos investigation. So no, that's the short answer. 01:02:09.000 --> 01:02:10.000 The kneeship. Is what you're looking for. 01:02:10.000 --> 01:02:11.000 Okay. 01:02:11.000 --> 01:02:15.000 The D-shaps, yes. Yep. 01:02:15.000 --> 01:02:40.000 Okay. I'm going to take another question here. How would you go about using ABS to evaluate the risk of a threatened release, such as a deteriorating building with ACM if it was not safe to enter? 01:02:40.000 --> 01:02:41.000 It's not safe to enter. I don't think we're going to enter it. 01:02:41.000 --> 01:02:42.000 Right. 01:02:42.000 --> 01:02:55.000 Well, you can… Right. Not without levels of protection. So you may want to do some bulk sampling ahead of time to check that. And that's one of the methods we'll talk about coming up. 01:02:55.000 --> 01:03:05.000 All right, excellent. I have several questions that are still coming in, which is fabulous. But I think just in the interest of time, we're going to pause here with the Q&A break. 01:03:05.000 --> 01:03:10.000 We're going to carry on with the presentation. However, we do have another Q&A break scheduled later on in the talk. 01:03:10.000 --> 01:03:16.000 So I'm going to go ahead and let my presenters and panelists turn their cameras off. I want to thank them for their time. 01:03:16.000 --> 01:03:26.000 I'll continue to invite you to peruse through the questions that are coming in. We'll carry on with the presentation. The audience is welcome to continue submitting questions for our speakers. 01:03:26.000 --> 01:03:34.000 And then again, we will have another pause here later on in our session. 01:03:34.000 --> 01:03:42.000 Characterization of potential human exposure to asbestos. Generally involves analytical testing using current methodologies. 01:03:42.000 --> 01:03:48.000 That afford accurate identification of fibrous material present in sample media. 01:03:48.000 --> 01:03:54.000 Accurate and precise quantitative results. Reproducibility among multiple testing laboratories. 01:03:54.000 --> 01:04:02.000 Flexibility, consensus acceptance of the method among asbestos professionals. And cost effectiveness. 01:04:02.000 --> 01:04:10.000 The framework provides recommendations for analyzing asbestos in soil. Settled dust and air. 01:04:10.000 --> 01:04:21.000 Analysis of asbestos in aqueous media is not addressed in the framework Because ingestion of asbestos via drinking water has not historically been considered an important exposure route at surplus sites. 01:04:21.000 --> 01:04:27.000 However, the safe drinking water act includes methods for analyzing asbestos and drinking water. 01:04:27.000 --> 01:04:41.000 If it is determined that asbestos in drinking water may be a complete exposure pathway at a site Remember that error analysis is needed for quantitative risk assessment calculations. 01:04:41.000 --> 01:04:51.000 This slide shows the various instruments that can be used for asbestos analysis. 01:04:51.000 --> 01:04:58.000 For bulk asbestos analysis of soil or ACM, A stereo microscope is used for initial analysis. 01:04:58.000 --> 01:05:07.000 Followed by a polarized light microscope, or PLM. The stereo microscope magnification can range from 6 to 50x. 01:05:07.000 --> 01:05:12.000 The PLM is used to identify asbestos based on optical properties. 01:05:12.000 --> 01:05:19.000 The PLM magnification can range from 100 to 400x. 01:05:19.000 --> 01:05:25.000 The phase contrast microscope, or PCM, is used for analyzing air samples. 01:05:25.000 --> 01:05:30.000 The PCM is used to identify fibers based on morphology only. 01:05:30.000 --> 01:05:40.000 It does not consider chemistry or crystalline structure. The PCM magnification is 400x. 01:05:40.000 --> 01:05:58.000 The scanning electron microscope, or SEM, can be used as an optional method to identify asbestos for either bulk samples or air filters. The SEM electron beam scans the surface of the sample and projects the result as an image of the surface on the screen. 01:05:58.000 --> 01:06:06.000 An SEM can be equipped with energy dispersive X-ray analysis or EDS to determine particle chemistry. 01:06:06.000 --> 01:06:10.000 The SEM has a wide range of magnification. 01:06:10.000 --> 01:06:17.000 From 24 to 300,000x. 01:06:17.000 --> 01:06:27.000 The transmission electron microscope, or TEM, is the recommended method for analyzing air samples and can also be used to analyze bulk samples. 01:06:27.000 --> 01:06:34.000 The TEM transmits an electron beam through the sample. Which projects an image on the screen. 01:06:34.000 --> 01:06:45.000 The TEM can be equipped with EDS. And select area electron diffraction or SAE D to determine chemistry and crystalline structure. 01:06:45.000 --> 01:06:50.000 The TEM can be used at low magnification. Approximately 5,000x. 01:06:50.000 --> 01:06:58.000 Or high magnification, approximately 20,000x. 01:06:58.000 --> 01:07:06.000 The framework presents four analytical methods for asbestos and soil. These methods differ in their preparation steps. 01:07:06.000 --> 01:07:14.000 Method selection is a site-specific decision. The EPA method was developed for bulk building materials. 01:07:14.000 --> 01:07:21.000 Or ACM, but is also used to analyze soil samples. The method includes various analytical techniques. 01:07:21.000 --> 01:07:33.000 But stereomicroscopy and PLM are mandatory. It also includes graphometric matrix reduction, such as ashing to remove cellulose such as leaves. 01:07:33.000 --> 01:07:37.000 Roots and paper. And or dilute acid treatment. 01:07:37.000 --> 01:07:41.000 To remove minerals such as calcite. Dolomite and gypsum. 01:07:41.000 --> 01:07:46.000 That could interfere with analysis. If interfering materials are present. 01:07:46.000 --> 01:07:52.000 Graphometric reduction improves detection of asbestos. And improves data quality. 01:07:52.000 --> 01:08:01.000 Carb435 is a state method developed by the California Air Resources Board For analysis of naturally occurring serpentine aggregate. 01:08:01.000 --> 01:08:06.000 It has been used over the years in a modified form by EPA regions. 01:08:06.000 --> 01:08:12.000 The ASTM method 7521 is specifically for soil analysis. 01:08:12.000 --> 01:08:18.000 It incorporates the gravimetric reduction steps from the EPA method by reference. 01:08:18.000 --> 01:08:25.000 It includes sieving based on particle size. With analysis of separate fractions. 01:08:25.000 --> 01:08:30.000 The optional TEM step in this method may be used for the fine fraction. 01:08:30.000 --> 01:08:40.000 The fluidized bed asbestos segregator will be discussed in more detail in upcoming slides. 01:08:40.000 --> 01:08:45.000 Soil results may guide the placement of air sampling locations for risk assessment. 01:08:45.000 --> 01:08:52.000 Please note that the use of the EPA600 method or other bulk building material methods. 01:08:52.000 --> 01:08:59.000 May exclude structures that would be included in an air sample as cleavage fragments. 01:08:59.000 --> 01:09:05.000 Cleavage fragments are formed by breaking larger mineral particles rather than being fibrous. 01:09:05.000 --> 01:09:13.000 The images on this slide show clear distinctions But many samples may be subject to interpretation. 01:09:13.000 --> 01:09:26.000 Laboratory interpretations of geology may vary. Trw assistance is available If this issue arises in your data. 01:09:26.000 --> 01:09:38.000 The fluidized bed asbestos segregator or FBAS, was developed for EPA to help determine low-level concentrations of asbestos and soil and other matrices. 01:09:38.000 --> 01:09:47.000 Such as vermiculite. It has also been successfully used for the determination of other elongated mineral particles such as Arianite. 01:09:47.000 --> 01:10:00.000 Bulk soil samples are processed in an FBAS using air to illustrate asbestos structures from sample soil and deposit them onto filter for analysis by transmission electron microscopy. 01:10:00.000 --> 01:10:06.000 Or TEM. 01:10:06.000 --> 01:10:19.000 This image shows the FBAS apparatus and its components. 01:10:19.000 --> 01:10:29.000 Other test method 42 is the approved EPA method for sampling Sample preparation, and operation of the fluidized bed asbestos segregator. 01:10:29.000 --> 01:10:41.000 Currently, there is limited availability to FBAS equipment. Epa's Region 10 lab and one commercial lab are the only locations where they are available. 01:10:41.000 --> 01:10:51.000 The FBAS has been incorporated into the framework. Additional research is being conducted to help better interpret data from the FBAS. 01:10:51.000 --> 01:10:56.000 It has been used to analyze samples from multiple sites. Including Davidson asbestos. 01:10:56.000 --> 01:11:06.000 Libby, Northridge Estates. Swift Creek, Frank Foundry, and Dort Food Storage. 01:11:06.000 --> 01:11:16.000 Dust samples analyzed using ASTM method 5755 may be used qualitatively or semi-quantitatively. 01:11:16.000 --> 01:11:21.000 To determine the area of contamination. Or confirm if a release has occurred. 01:11:21.000 --> 01:11:28.000 When analyzing settled dust by TEM, The preparation steps may break asbestos structures. 01:11:28.000 --> 01:11:33.000 Especially chrysotile bundles. Into multiple fibers. 01:11:33.000 --> 01:11:40.000 Also, different counting rules are used, which could potentially lead to higher or lower results than error analysis. 01:11:40.000 --> 01:11:47.000 The small area that is sampled for dust means results may not be representative of a larger area. 01:11:47.000 --> 01:11:56.000 Also, while asbestos and settled dust results may appear high. This does not necessarily indicate high exposure in the breathing zone. 01:11:56.000 --> 01:12:03.000 Trw consultation is recommended for indoor dust scenarios. 01:12:03.000 --> 01:12:10.000 Air samples can be collected from stationary or personal monitors worn during ABS activities. 01:12:10.000 --> 01:12:18.000 Niosh 7400. Is the PCM method that can be used to analyze air samples for screening purposes. 01:12:18.000 --> 01:12:23.000 Pcm cannot distinguish asbestos fibers from non-asbestos fibers. 01:12:23.000 --> 01:12:31.000 So the screening result has limited use. Samples are analyzed at 400x magnification in this method. 01:12:31.000 --> 01:12:37.000 Tem can be used to analyze samples at low and high magnifications. 01:12:37.000 --> 01:12:50.000 There are different methods for direct and indirect TEM analysis. Direct methods retain structures in the same relative position during analysis as they were on the original sample filter. 01:12:50.000 --> 01:13:07.000 Whereas indirect methods involve dispersing the particulate matter from the original sample filter into a liquid and capturing the suspended particulates onto intermediate filters that are then prepared for analysis. 01:13:07.000 --> 01:13:13.000 The next two slides present the asbestos TRWs recommended air analysis approach. 01:13:13.000 --> 01:13:20.000 Tem is preferred to PCM for characterization of exposures to inform decisions at circler sites. 01:13:20.000 --> 01:13:32.000 Samples should be collected on 0.8 micrometer mixed cellulose ester or MCE filters. For most CERCLA air sampling applications to avoid filter overload. 01:13:32.000 --> 01:13:37.000 The photos on this slide show a filter and sampling cassettes with filters. 01:13:37.000 --> 01:13:43.000 Iso method 10312 should be used for direct TEM analysis at a low magnification. 01:13:43.000 --> 01:13:49.000 Of at least 5,000x. 01:13:49.000 --> 01:13:54.000 Pcme counting rules with modifications for structure type should be followed. 01:13:54.000 --> 01:14:03.000 Pcme refers to structure seen in a TEM that are considered equivalent to structures that are visible in a PCM. 01:14:03.000 --> 01:14:13.000 When analyzing asbestos samples. Microscopists refer to a set of rules that dictate which visible structures to be counted or considered asbestos. 01:14:13.000 --> 01:14:22.000 Tem methods require that the microscopist classify each primary fibrous structure into one of the four fundamental categories. 01:14:22.000 --> 01:14:26.000 Fibers, bundles. Clusters and matrices. 01:14:26.000 --> 01:14:33.000 The framework recommends that PCME structures counted include only fibers and bundles. 01:14:33.000 --> 01:14:40.000 With a width range between 0.2 micrometers and 3.0 micrometers. 01:14:40.000 --> 01:14:48.000 A length greater than 5 micrometers and an aspect ratio greater than or equal to 3 to 1. 01:14:48.000 --> 01:14:52.000 The aspect ratio is the ratio of the length to the width of a structure. 01:14:52.000 --> 01:15:01.000 The framework provides additional details about what should be counted by the microscopist. 01:15:01.000 --> 01:15:13.000 Alternate approaches for error analysis include ISO method. 13794 for indirect TEM analysis In ISO method 14966. 01:15:13.000 --> 01:15:22.000 For SEM analysis. The indirect TEM method should only be used when filter overload does not allow for direct analysis. 01:15:22.000 --> 01:15:30.000 The use of indirect analytical results should be considered on a side-by-site basis and may be useful for decision making. 01:15:30.000 --> 01:15:35.000 But direct analytical results are preferred for risk assessment where feasible. 01:15:35.000 --> 01:15:41.000 The SEM method may be used as a supplement to TEM for visualization. 01:15:41.000 --> 01:15:49.000 Sem Analysis will provide more detailed information on surface topography and morphology. 01:15:49.000 --> 01:16:00.000 Sensitivity and detection levels for error analysis by TEM are determined by the volume of air collected and the area of the filter counted by the analyst. 01:16:00.000 --> 01:16:07.000 Sensitivity is defined as the concentration corresponding to the detection of one structure in the analysis. 01:16:07.000 --> 01:16:13.000 The sensitivity for a sample is determined by the volume of air drawn through the sample filter. 01:16:13.000 --> 01:16:20.000 The active area of the filter The number of grid openings on a filter analyzed by a microscopist. 01:16:20.000 --> 01:16:36.000 And the area of each grid opening analyzed. The level of detection, or LOD, is equivalent to a reporting level and expresses the uncertainty around the sensitivity level for non-detects. It is the upper bound of the counting error for zero structures 01:16:36.000 --> 01:16:43.000 And can be calculated as 2.99 times the analytical sensitivity or about three structures. 01:16:43.000 --> 01:16:49.000 The LOD should be at or below the level of concern or LOC. 01:16:49.000 --> 01:16:56.000 There may be several practical constraints that limit the sample volume and the number of grid openings analyzed. 01:16:56.000 --> 01:17:01.000 The volume of air collected is given as the product of pump flow rate and collection time. 01:17:01.000 --> 01:17:11.000 Time for collection of air volume may be limited by the amount of time a sampler is able to maintain an ABS activity and full PPE. 01:17:11.000 --> 01:17:18.000 The maximum sampling time for a personal air sample associated with ABS is usually about two to four hours. 01:17:18.000 --> 01:17:23.000 At some sites, much lower flow rates may be needed to avoid overloading a filter. 01:17:23.000 --> 01:17:37.000 Depending on activity and site conditions. The time and cost of analysis is directly related to the number of grid openings analyzed. 01:17:37.000 --> 01:17:40.000 All right. At this point, we're going to switch over to a short video. 01:17:40.000 --> 01:17:44.000 And then we will have our last Q&A break for the day. 01:17:44.000 --> 01:17:48.000 So I'm going to call up the next video 01:17:48.000 --> 01:18:10.000 Analytical laboratory methods for asbestos. The following video provides a brief overview of analytical methods covered in the 2021 Framework for Investigating Asbestos Contaminated surplus sites. This video will cover typical laboratory methods for analyzing soil and air collected at asbestosites. 01:18:10.000 --> 01:18:24.000 Soil analytical methods for site characterization. Epa 600 method. This method is primarily used to analyze bulk building materials. 01:18:24.000 --> 01:18:36.000 While not a soil method, the EPA 600 method may be necessary on surplus sites which may present situations where soil construction debris and building materials may be present. 01:18:36.000 --> 01:18:44.000 The method includes stereoscopics. Examination followed by a polarized light microscopy techniques. 01:18:44.000 --> 01:18:55.000 The gravimetric reduction preparation method may be included in the EPA 600 method to produce a more accurate estimate for samples in the 1% range. 01:18:55.000 --> 01:19:10.000 Limit for this method is typically 1%. The asbestos mineral type is determined by observations of optical properties such as extinction angle Signs of elongation and dispersion staining. 01:19:10.000 --> 01:19:21.000 California Air Resource Board Method 435. This method was developed to determine asbestos content of serpentine aggregate and is commonly used to detect asbestos. 01:19:21.000 --> 01:19:30.000 Soil. Sample preparation may require a disc mill to achieve desired material size. 01:19:30.000 --> 01:19:37.000 Once required material size is achieved, sample is transferred to a container for stereoscope examination. 01:19:37.000 --> 01:19:46.000 Following stereoscope examination, a slide is prepared for a 400 point count analysis by PLM technique. 01:19:46.000 --> 01:19:58.000 Carb435 method has a detection limit of 0.25%. Astm D7521-16. 01:19:58.000 --> 01:20:07.000 The ASTM method for determination of asbestos in soil is based on sieving of soil rather than grinding homogenation. 01:20:07.000 --> 01:20:18.000 Soil is dried prior to sieve. Once dry, soil is placed in sieve to separate out coarse, medium, and fine fractions. 01:20:18.000 --> 01:20:25.000 The option for a wet sieving procedure is available and can improve detection of asbestos structures. 01:20:25.000 --> 01:20:30.000 The three separate fractions are then weighed and examined with a stereoscope. 01:20:30.000 --> 01:20:38.000 Following visual examination, a slide is prepared from the fine fraction for a 400 point count analysis. 01:20:38.000 --> 01:20:46.000 The slide is then analyzed by PLM analysis. The ASTM method has a detection limit of 0.25%. 01:20:46.000 --> 01:20:57.000 With optional TEM analysis, sensitivity can be achieved to 0.1%. Fluidized bed asbestos segregator. 01:20:57.000 --> 01:21:04.000 This method is designed to quantify mineral fibers present in soil or other solid media. 01:21:04.000 --> 01:21:17.000 This method uses a specialized preparation method followed by TEM analysis. Detection limits of approximately 100 times lower than typical soil methods can be achieved. 01:21:17.000 --> 01:21:26.000 This method has limited laboratory availability and should be discussed prior to field activities. 01:21:26.000 --> 01:21:35.000 Air analytical methods for site characterization. Iso 10312. 01:21:35.000 --> 01:21:42.000 The ISO 10312 method is the recommended method for error analysis under the decision framework. 01:21:42.000 --> 01:21:50.000 The method includes a direct transfer analysis by transmission electron microscopy . 01:21:50.000 --> 01:21:55.000 Sample cassettes are prepared for analysis by placing sample filters on slides. 01:21:55.000 --> 01:22:01.000 Slides are transferred to a plasma asher chamber until the filters are completely ashed. 01:22:01.000 --> 01:22:08.000 Slides are then carbon coated in a vacuum chamber. 01:22:08.000 --> 01:22:18.000 Once sufficient carbon coating is achieved, media is placed on TEM specimen grids. 01:22:18.000 --> 01:22:29.000 Tem specimen grids are then analyzed by TEM method. Analytical sensitivity varies and must be specified by the end user. 01:22:29.000 --> 01:22:38.000 Final results for risk assessment calculations only include structures meeting the PCME requirements for length and width. 01:22:38.000 --> 01:22:47.000 Asbestos is identified by a combination of morphology observed by TEM, Chemistry determined by energy dispersive X-ray analysis. 01:22:47.000 --> 01:22:56.000 And crystal structure determined by select area electron diffraction. Iso 13794. 01:22:56.000 --> 01:23:02.000 It is common for field samples collected for ISO 10312 to become overloaded. 01:23:02.000 --> 01:23:07.000 When a filter becomes overloaded, direct analysis is no longer possible. 01:23:07.000 --> 01:23:23.000 Iso 13794 is an indirect method that can be used to analyze overloaded filters The overloaded filter is removed from the cassette and cut into required sections and placed into a beaker. 01:23:23.000 --> 01:23:34.000 The beaker is placed in a plasma asher until the filter is completely ashed. 01:23:34.000 --> 01:23:51.000 During ashing, the filter apparatus is prepared. 01:23:51.000 --> 01:24:03.000 Once filter is ashed, solution is added and the sample is sonicated. 01:24:03.000 --> 01:24:12.000 Following sonication, the sample is filtered. 01:24:12.000 --> 01:24:25.000 Once liquid is filtered, the filter is removed and placed in a dryer. 01:24:25.000 --> 01:24:41.000 Once sufficiently dry, the filter is prepared for TEM analysis following the ISO 10312 methods previously discussed. 01:24:41.000 --> 01:24:54.000 Niosh 7400 method. Phase contrast microscopy, PCM, is typically used for personal air sampling and perimeter monitoring in occupational environments. 01:24:54.000 --> 01:25:04.000 The NIOSH 7400 method may be a useful screening tool, but it is important to note that the PCM analysis only provides results in fibers. 01:25:04.000 --> 01:25:16.000 And does not determine asbestos concentrations. Sepho cassettes are prepared for analysis by removing one quarter section from the filter to mount on slide for analysis. 01:25:16.000 --> 01:25:28.000 After prepping, the slide is examined by PCM analysis The remaining portions of the filter may be archived for future analysis by TEM methods. 01:25:28.000 --> 01:25:44.000 The PCM method may be conducted on site and may be a quick and cost-effective screening tool at surplus sites. Again, fibers are evaluated by morphology only so asbestos is not differentiated from other fibers. 01:25:44.000 --> 01:25:56.000 Astm D5755. This method is used for determination of asbestos in settled dust. 01:25:56.000 --> 01:26:11.000 Sample is first prepared by rinsing the sample cassette and collecting the rinseate in a beaker. 01:26:11.000 --> 01:26:19.000 The rinse solution is then sonicated. 01:26:19.000 --> 01:26:31.000 During sonication, the filter apparatus is prepared. 01:26:31.000 --> 01:26:43.000 Following sonication, the solution is filtered. 01:26:43.000 --> 01:26:56.000 One solution is removed, the filter is collected and dried. 01:26:56.000 --> 01:27:04.000 After filter is sufficiently dry, the filter is prepared for TEM analysis as previously discussed. 01:27:04.000 --> 01:27:23.000 The steps included in this method are also used to analyze asbestos wipes and asbestos in drinking water. 01:27:23.000 --> 01:27:28.000 Okay, we're now going to move into our final Q&A break for the day. 01:27:28.000 --> 01:27:29.000 So I'm going to invite our 01:27:29.000 --> 01:27:37.000 For further information, please reference the asbestos TRW Technical Resource webpage located here. 01:27:37.000 --> 01:27:44.000 Note that as updated guidance is released by the asbestos TRW, It will be posted to this webpage. 01:27:44.000 --> 01:27:49.000 If you have any asbestos questions or would like an asbestos TRW consultation. 01:27:49.000 --> 01:27:59.000 You can send an email to asbestoshelp at epa.gov or contact your regional TRW representative. 01:27:59.000 --> 01:28:05.000 All right, so I'll invite all of my panelists to come on camera and we'll get ready for our final Q&A segment. 01:28:05.000 --> 01:28:11.000 Again, if you are in the audience, this is your chance to type in questions or comments for our presenters. 01:28:11.000 --> 01:28:22.000 What I'm going to do is start with the questions that came in on this most recent module. We had a few people who commented that they appreciated the video and they are looking forward to when that will be publicly available to replay. 01:28:22.000 --> 01:28:31.000 We do have some questions, though. Regarding some of the analysis work that they saw in the video. 01:28:31.000 --> 01:28:37.000 One of the very first questions. They noticed that the lab tech was not wearing a mask. 01:28:37.000 --> 01:28:46.000 And they just wondered what sort of masks or PPE would normally be used when they were testing for asbestos like that in a lab. 01:28:46.000 --> 01:28:58.000 I can probably take this one. So a lot of the work that they're probably doing is done under HEPA filtration hoods, workstations probably the room too. 01:28:58.000 --> 01:29:16.000 So yeah, they're… Typically, you know, in the lab, you're wearing, you know, gloves, lab coat um But most of the work is where the actual asbestos is being handled is usually in a workstation that's got HEPA filtration. 01:29:16.000 --> 01:29:17.000 Okay, we have a question about Oh, go ahead. 01:29:17.000 --> 01:29:33.000 Yeah, I've seen that too, Jed. Sorry, but I also noticed no gloves and a couple of them too. And I know that's also PPE that sometimes It's just critical and understood that you'll be wearing gloves for some of this prep. 01:29:33.000 --> 01:29:34.000 Excellent. 01:29:34.000 --> 01:29:38.000 And safety glasses. 01:29:38.000 --> 01:29:42.000 Okay, how about the approximate weight of the final sample that is analyzed? 01:29:42.000 --> 01:29:49.000 Someone is wondering how much of the five kilogram sample gets sipped. 01:29:49.000 --> 01:29:50.000 Jed. 01:29:50.000 --> 01:29:58.000 Well, there's two questions there. So the five kilogram sample um Not five kilograms, probably. 01:29:58.000 --> 01:30:05.000 Like I said, when we're doing these incremental samplings, you bring it into the lab. 01:30:05.000 --> 01:30:09.000 You spread it out on a sheet and then you incrementally sample it again. 01:30:09.000 --> 01:30:18.000 You know, 30, 100, however many increments was decided on in the in the planning of the project. 01:30:18.000 --> 01:30:22.000 The amount that actually gets analyzed depends on the method that you're using. 01:30:22.000 --> 01:30:30.000 You know, when you're doing a PLM, it's fractions of a gram um That's spread out on a slide. 01:30:30.000 --> 01:30:52.000 When you're talking about amount of of material that's analyzed under a transmission electron microscope. Boy, I don't even know the weight wouldn't matter. That's more of an area in the area of a TEM grid is only about the size of a head of a pin. 01:30:52.000 --> 01:31:05.000 So it's very small. Not very representative. You know, you probably need to need to consider that when you're trying to interpret the data. 01:31:05.000 --> 01:31:13.000 But I think that That answers both of those questions as best I can. 01:31:13.000 --> 01:31:19.000 Yeah, and there's another question, I think, by the same Ask her. 01:31:19.000 --> 01:31:32.000 The same questioner about the questioner about sample volume and taking increments of the composite how to determine the representatives of the final sample and how that gets analyzed. 01:31:32.000 --> 01:31:39.000 You know, one of the things that we can do is take take replicate samples of that sample. 01:31:39.000 --> 01:31:57.000 But incremental sampling is all about maintaining that representativeness five kilograms sounds like a lot of dirt, but when you're looking over a half acre, an acre of soil, that's a pretty small amount And you want to make sure that what you're aiming to do is make sure that that sample is representative 01:31:57.000 --> 01:32:18.000 Of your decision unit, whatever goes under Jed's um onto his slides for microscopy should be representative of that larger sample so there's things that we can do to be systematic and rigorous in how we pick the very small amount that actually gets analyzed. 01:32:18.000 --> 01:32:36.000 But this gets to some of the complexity of addressing soil asbestos and soil in the first place. And it is very complicated But one of the things that you can do to see if that sample that fraction of a gram is representative of the larger samples 01:32:36.000 --> 01:32:46.000 Take replicates of that sample. Incrementally subsample it several times and see if you're getting kind of concordant answers. 01:32:46.000 --> 01:33:02.000 And that would all be covered under the planning, the quality assurance project plan Your frequency of duplicates and replicates You know, that's just part of the QA program. 01:33:02.000 --> 01:33:12.000 Speaking of replicates, do you have a suggestion on the number of replicates that is recommended for each decision unit for ISM? 01:33:12.000 --> 01:33:18.000 Sure. Yeah. What standard is doing three triplicates. 01:33:18.000 --> 01:33:29.000 In one study, we… Did five because we wanted to see if it mattered yeah if we got… more samples, would that give us more power in our statistics? 01:33:29.000 --> 01:33:44.000 We were collecting 100 increment samples in a quarter acres. So we had 500 holes in the ground that might have been more than we needed. I think we replicants is what we typically do. 01:33:44.000 --> 01:33:52.000 Okay. Does EPA require analysis of vermiculite insulation to confirm the presence of asbestos? 01:33:52.000 --> 01:33:57.000 If so, what analytical method is used? 01:33:57.000 --> 01:34:02.000 I know that PLM. Which is for bulk sample analysis would be recommended. 01:34:02.000 --> 01:34:12.000 But getting to the first part of the question. I have seen advice that assume all vermiculite insulation. 01:34:12.000 --> 01:34:19.000 May contain asbestos. But the reality is you won't know without lab analysis. 01:34:19.000 --> 01:34:28.000 So I don't know. I don't think we actually require vermiculate insulation be be sampled. 01:34:28.000 --> 01:34:32.000 Undergo PLM. But that's just one of those. Go ahead, David. 01:34:32.000 --> 01:34:33.000 Good night. 01:34:33.000 --> 01:34:49.000 Oh. There is a program Sponsored by… W.R. Grace to analyze vermiculite from home insulation. 01:34:49.000 --> 01:35:07.000 And that's the zonolite attic insulation trust. And… if you suspect that you have vermiculite in your attic insulation You can contact them. 01:35:07.000 --> 01:35:19.000 They will send you a container and a shipping container. And you can take a sample of that material, put it in the container and send it to them. 01:35:19.000 --> 01:35:26.000 And they will determine whether or not that vermiculite came from from Libya or not. 01:35:26.000 --> 01:35:34.000 And if it did come from Libby, there is some financial help. 01:35:34.000 --> 01:35:47.000 That is offered through the trust. That allows you to pay for part of the removal of the material from your attic. 01:35:47.000 --> 01:35:57.000 And I just wanted to add, there is actually an EPA research method for sampling and analysis of fibrous amphibole and vermiculite attic insulation. 01:35:57.000 --> 01:36:02.000 Epa 600 slash dash 04 slash 004. 01:36:02.000 --> 01:36:28.000 And I'll write that one down in the chat. That is a method that can be used. It's similar to the certainly the steps in the analysis are similar to the EPA 600 method. The bulk uh building material method, but it's got some interesting information on the unique optical properties of the 01:36:28.000 --> 01:36:32.000 Amphibole found in vermiculite. 01:36:32.000 --> 01:36:38.000 Okay. Speaking of vermiculate, someone is asking if it's used in potting soils. 01:36:38.000 --> 01:36:46.000 And they then go on to say, well, wouldn't it be reasonable to suspect that any vermiculite might have asbestos? 01:36:46.000 --> 01:36:53.000 Yes, that's true. And one of the things that we used to pack our samples in was vermiculite way back in the day. 01:36:53.000 --> 01:37:03.000 So that was also a requirement that we could not ship asbestos samples in vermiculite. So yes, that is a potential issue. 01:37:03.000 --> 01:37:12.000 Okay. We have a question about that. Pesky building that is unsafe to go into for sampling purposes. 01:37:12.000 --> 01:37:18.000 If asbestos contamination is suspected inside a building or other area that is unsafe to enter. 01:37:18.000 --> 01:37:29.000 Might remote control vehicles or drones be used for sampling? 01:37:29.000 --> 01:37:39.000 They might. I'm not aware of that ever having occurred. 01:37:39.000 --> 01:37:44.000 It's not something that we've done. It's not to say that it couldn't be. 01:37:44.000 --> 01:37:53.000 Yeah, so UAS for drones, obviously were used quite a bit for wildfire response and uh We're approaching unsafe buildings. 01:37:53.000 --> 01:38:08.000 Mainly just for visual and video reconnaissance to send back to someone that could sit at a comfy desktop and say, oh, that looks like there's some translate there or Or maybe identify some of the hazards before the samples were collected or 01:38:08.000 --> 01:38:13.000 Safety precautions were taken. 01:38:13.000 --> 01:38:29.000 Okay. A question about soils. Why would you suspect asbestos in the soils in the first place? Is this to look for naturally occurring asbestos sites where there was an old building that was demolished? We have an attendee who joined a little bit late. So just to recap if somebody missed this in the beginning. 01:38:29.000 --> 01:38:33.000 Welcome to the Superfund program. All of the above. 01:38:33.000 --> 01:38:36.000 All of the above. 01:38:36.000 --> 01:38:43.000 Mining would be disturbance of naturally occurring buildings that have been knocked over. 01:38:43.000 --> 01:38:55.000 We've had several sites where unscrupulous people have come in to strip the insulation off of pipes to to steal the pipes for recycling. 01:38:55.000 --> 01:39:06.000 Which has resulted in widespread damage and spreading the the uh the asbestos all over the surrounding soils. 01:39:06.000 --> 01:39:15.000 So there's all kinds of ways that that they end up in the soil and it becomes a super fund. 01:39:15.000 --> 01:39:22.000 Issue. 01:39:22.000 --> 01:39:23.000 Yeah. 01:39:23.000 --> 01:39:33.000 Yeah, a big one from Tim's region are botched cleanups, botched B shaft cleanups where someone's trying to undertake it and they only get so far, either run out of money or interest or or resources to do it. 01:39:33.000 --> 01:39:36.000 Stuff is just scattered, right? Scattered in an old building or the property around it or stored out back, whatever it might be. 01:39:36.000 --> 01:39:56.000 Yeah. Yeah, we had a case where we had a case a… criminals they went to jail recruited people at the corner liquor store to come in and remove the asbestos and They weren't trained. 01:39:56.000 --> 01:40:07.000 So they were breaking ocean you know osha violations knee shops violations, just all sorts of laws and regulations and they went to jail. 01:40:07.000 --> 01:40:14.000 But yeah, when it becomes a super fund issue, things have gone wrong. 01:40:14.000 --> 01:40:26.000 Okay. A question about personal exposure monitoring. Should results from that work And when it's collected, should it be collected to provide a NEA during sampling? 01:40:26.000 --> 01:40:33.000 And then be used as a line of evidence that asbestos is or is not a concern at a site. 01:40:33.000 --> 01:40:39.000 We've had a site where a negative exposure assessment, those of you who don't know what NEA is. 01:40:39.000 --> 01:40:47.000 That's an OSHA thing. It can be it has some similarities to ABS. 01:40:47.000 --> 01:40:53.000 You know, it's workers. In protective equipment. 01:40:53.000 --> 01:41:10.000 With personal air monitoring. We've had a site where we've had a site NEA was used just to downgrade the workers stuff but it's it's not a An NEA is not a not an EPA sampling protocol. 01:41:10.000 --> 01:41:32.000 There, we knew that there was asbestos present we had data And, you know, to show that it needed to be removed it was just an occupational health thing and what the workers were. So no, we didn't use it as a line of evidence in that case. Has anybody else encountered 01:41:32.000 --> 01:41:41.000 Nea at your sites? 01:41:41.000 --> 01:41:47.000 Doesn't sound like it. Yeah, so it's not… It's not something that we use. 01:41:47.000 --> 01:42:09.000 Okay. All right, I'm going to go to a question. If you have buried non-fryable material in soil What parameters would you analyze for soil to confirm the presence of asbestos? 01:42:09.000 --> 01:42:15.000 Well, I guess we would be sampling or asbestos, if I'm understanding the question. 01:42:15.000 --> 01:42:22.000 Correctly we would be using our standard, you know, one of the analytical methods that we've talked about. 01:42:22.000 --> 01:42:28.000 Today. To analyze that soil and determine if that's present. 01:42:28.000 --> 01:42:29.000 Yeah. 01:42:29.000 --> 01:42:38.000 Obviously, if it's buried, we can't do anything like ABS. Because it's buried. So we would um you know to collect the samples and analyze them for asbestos. 01:42:38.000 --> 01:42:59.000 To see if they're present. We might look in the soils that we're collecting to see if there's any visible ACM, asbestos containing materials that might lead us to indicate that the subsurface is even contaminated. 01:42:59.000 --> 01:43:00.000 Yes. 01:43:00.000 --> 01:43:06.000 This is kind of like the Northridge Estates or the Mountain Home Air Force Base where the non-fryable stuff got buried. But over time It's going to resurface. 01:43:06.000 --> 01:43:07.000 Yeah. 01:43:07.000 --> 01:43:24.000 It will, you know, through erosion and frost heaving and different things like that, the active moisture on the on the material will eventually affect the stability of it and it'll start to release fibers And then you may find it in the soil. 01:43:24.000 --> 01:43:33.000 But yeah, you're kind of looking at two different things there the the uh the bulk material and then the soil. 01:43:33.000 --> 01:43:36.000 And eventually the one is going to wind up in the other. 01:43:36.000 --> 01:43:53.000 Okay. And speaking of that. Is there any evidence of upward migration of asbestos fibers through soil? They specifically asked about a scenario with ACM capped in place and weather factors like freezing and thawing. 01:43:53.000 --> 01:44:06.000 Yes. And that… example that Chad just talked about in North Ridge Estates is This may be the classic you know they would clean up the surface soil And think they were done in a year later. 01:44:06.000 --> 01:44:10.000 There's more asbestos visible at the surface. So yes, that is a common That is something that can happen. 01:44:10.000 --> 01:44:17.000 Yeah. Yeah, it's called biopperturbation. 01:44:17.000 --> 01:44:26.000 And just, I think a related question, is there data on temporal effects of soil borne air asbestos concentrations? 01:44:26.000 --> 01:44:42.000 With regard to ACM weathering. They wonder, will ABS results be similar now compared to 100 years in the future after weathering? 01:44:42.000 --> 01:44:44.000 We haven't done the 100-year test yet, but yet 01:44:44.000 --> 01:44:53.000 Good question. Yeah, I… we would suspect that over 100 years that those fibers would break up. 01:44:53.000 --> 01:44:57.000 And be probably result in higher. 01:44:57.000 --> 01:45:03.000 Concentrations over time. But yeah, I'm not aware of any studies that have looked at it. 01:45:03.000 --> 01:45:04.000 Temporally. 01:45:04.000 --> 01:45:12.000 Can we repeat the study that showed upward migration? What was the name of the site? 01:45:12.000 --> 01:45:13.000 Northridge Estates. 01:45:13.000 --> 01:45:14.000 Northridge estate? Yeah. 01:45:14.000 --> 01:45:31.000 Northridge Estates, okay. All right. Okay. Let's talk a little bit about wipe and soil samples. This one came in earlier in the session today and one of the participants wondered, should wipe and soil samples be used to assess risk to potential future receptors? 01:45:31.000 --> 01:45:44.000 Whereas air is better for current receptors. They note that wipe and soil analytical results could inform about what has the potential to be mobilized to the air conditions, which are different than current. 01:45:44.000 --> 01:45:45.000 Yeah. 01:45:45.000 --> 01:45:52.000 The only metric that we have for assessing risk is via the inhalation pathway. 01:45:52.000 --> 01:45:59.000 Those are the only toxicity factors that we have are for inhalation exposures only. 01:45:59.000 --> 01:46:04.000 So we are limited to assessing risk. 01:46:04.000 --> 01:46:10.000 To the air pathway. 01:46:10.000 --> 01:46:11.000 Okay. 01:46:11.000 --> 01:46:26.000 Yeah. And again, you would… maybe collect those soil and dust samples to to better understand where the releases have occurred, where you might want to collect air data where you might want to do ABS and things like that. 01:46:26.000 --> 01:46:34.000 It definitely plays a role in your investigation, but the risk assessment is always going to be on the air. 01:46:34.000 --> 01:46:35.000 It helps target, target where you want to do your ABS. 01:46:35.000 --> 01:46:38.000 Okay. 01:46:38.000 --> 01:46:40.000 Yeah. 01:46:40.000 --> 01:46:49.000 Okay. A question about a site that has a remedy that's been implemented and your site is currently in O&M operation and maintenance. 01:46:49.000 --> 01:46:55.000 They wonder how often would you recommend ambient air sampling in ABS? 01:46:55.000 --> 01:47:00.000 I'll speak on this one a little bit. The site I'm currently working on. 01:47:00.000 --> 01:47:05.000 It's part of the rod requires that this be done in addition to soil sampling. 01:47:05.000 --> 01:47:22.000 For other parameters as well. So we've done it three years in a row, but it varies. It all depends if you're If it's dictated in the rod or If you do some visual inspections, I know there's been multiple sites that have had 01:47:22.000 --> 01:47:30.000 Boring animals come up and bring things to the surface. So there's something you may want to look at as you go forward. 01:47:30.000 --> 01:47:38.000 So yeah, as far as recommendation It's just part of your regular O&M inspector cap. If you see something, you might have to do something. 01:47:38.000 --> 01:47:40.000 Okay. 01:47:40.000 --> 01:47:56.000 The other situation that we've have in our region The remedy was conducted under our removal program by time critical removal action by our emergency response group. 01:47:56.000 --> 01:48:16.000 And it was a fill material was from an asbestos plant was used in residential yards And we sampled as many yards as we could. And there was an understanding that there may continue to be asbestos present. So part of the long-term operations and maintenance of the city 01:48:16.000 --> 01:48:27.000 In the state have taken on. Is working with the utilities and landowners If they encounter ACMC, it triggers. 01:48:27.000 --> 01:48:32.000 Some actions that that the property owner will need to take. 01:48:32.000 --> 01:48:38.000 Or the utilities will need to implement to keep their workers safe, keep the residents safe. 01:48:38.000 --> 01:48:44.000 It's going to be site specific and depend on It depends on the remedy. 01:48:44.000 --> 01:48:58.000 If there's anything left, you know, many remedies We'll hopefully have addressed all the material present but you know in in the case cases where you're unsure there's some uncertainty, you can put some measures in place. 01:48:58.000 --> 01:49:06.000 Okay, I know we are coming close to our scheduled end time, so we'll take one or two more questions with the time that we have remaining. 01:49:06.000 --> 01:49:10.000 And then I do have some additional reminders before we close things out today. 01:49:10.000 --> 01:49:18.000 This next one. Gets into just thoughts or considerations for state regulators. 01:49:18.000 --> 01:49:38.000 So they wonder if you have some ideas of some obstacles that our state regulators who are accepting risk-based ABS sampling for site characterization and closure might encounter. 01:49:38.000 --> 01:49:44.000 That's hard to answer from our position as feds. 01:49:44.000 --> 01:49:52.000 I think it would… may maybe just depend on 01:49:52.000 --> 01:50:12.000 The state's asbestos program, they will have a delegated program they have asbestos folks, you know, they have hazardous waste folks who were dealing with circular like projects. I think it's just going to depend on the state and the personnel that they have. 01:50:12.000 --> 01:50:20.000 But, you know. We on the TRW are always available to assist in any way that we can. 01:50:20.000 --> 01:50:34.000 So if a state folks that are on If you're wanting to pursue this or you've somebody hands you the data and you need some assistance interpreting it, you can feel free to reach out. 01:50:34.000 --> 01:50:39.000 To us anytime via the The link here. 01:50:39.000 --> 01:50:40.000 Okay. 01:50:40.000 --> 01:51:01.000 And I would only add cost considerations. Some of the ABS samples, depending on the sensitivity required. If you can't collect enough volume on your sample media you may have to count additional grids in order to meet that sensitivity and that's where you can run into cost overruns in your original budget. 01:51:01.000 --> 01:51:06.000 Okay, excellent. Now, I did see a number of questions that came into the queue earlier. 01:51:06.000 --> 01:51:23.000 I'm sorry, there's a lot of positive feedback that just came in some of the attendees have been very engaged today, so they appreciated your time and expertise but A number of people have asked risk related questions. And I know that the webinar is going to carry on tomorrow and in 01:51:23.000 --> 01:51:31.000 Part two, we'll talk a bit about risk. But I wanted to offer perhaps a sneak peek motivation. This is an ecological risk question. 01:51:31.000 --> 01:51:39.000 They just wonder if there's evidence of bioaccumulation or biomagnification of ACM in wildlife. 01:51:39.000 --> 01:51:58.000 I might be able to take that one. So in general, the exposure and the effects of asbestos through inhalation, it's a long-term chronic kind of thing and kind of thing again in speaking in generalities, many of the wildlife don't live long enough 01:51:58.000 --> 01:52:08.000 To show the impacts. It's still an inhalation aspect. So they'd have to be in an area where they could breathe it in. 01:52:08.000 --> 01:52:14.000 We generally don't see a lot with ecological risk in asbestos. 01:52:14.000 --> 01:52:15.000 All right, excellent. 01:52:15.000 --> 01:52:23.000 We do, however, know. That in the case of the Libya asbestos Superfund site. 01:52:23.000 --> 01:52:33.000 That… mineral fibers have been detected in fish tissue and in animal tissues. 01:52:33.000 --> 01:52:44.000 That. Where either the fish or the uh the land-based animal has come in contact with either soil or water. 01:52:44.000 --> 01:52:50.000 So we do know that mineral fibers do get into the tissues. 01:52:50.000 --> 01:53:00.000 Of ecological receptors. We don't have any ecological benchmarks to assess asbestos. 01:53:00.000 --> 01:53:07.000 Toxicity and… ecological receptors. 01:53:07.000 --> 01:53:17.000 But we do know that we do know that mineral fibers have been detected in ecological critters. 01:53:17.000 --> 01:53:27.000 All right. Well, with that and just a minute or two remaining on our time, I'm going to go ahead and close out This portion of part one in our final Q&A break. 01:53:27.000 --> 01:53:35.000 And I want to thank our panelists for joining us today, as well as the over 200 live attendees who were here for today's broadcast. 01:53:35.000 --> 01:53:44.000 And I want to make sure that everyone comes back tomorrow for part two, the final part in this series on the framework for investigating asbestos contaminated circle sites. 01:53:44.000 --> 01:53:53.000 For those of you that found this to be a very engaging and eye-opening seminar, the fun continues tomorrow at 1 p.m. Eastern, where we'll be joined by the same panel of experts. 01:53:53.000 --> 01:53:59.000 With a few additional guests. So I encourage you to make sure you have it on your calendar. You'll participate. 01:53:59.000 --> 01:54:03.000 Connect following the exact same instructions that you used for today. 01:54:03.000 --> 01:54:10.000 And if you have a colleague that you think could benefit from it, registration is still open. They are certainly welcome to sign up and join us for part two. 01:54:10.000 --> 01:54:16.000 Again, which will take place on Cluwen. I'm going to walk through just a few quick final reminders today before we close things out. 01:54:16.000 --> 01:54:24.000 So hopefully you all are familiar with the cleanup information network or cluwen.org and are visiting that as a hazardous waste site cleanup or characterization professional. 01:54:24.000 --> 01:54:31.000 Make sure you are subscribed for our free monthly newsletter, Tech Direct. I send that out on the first of each month and we'll highlight free sessions like today's. 01:54:31.000 --> 01:54:46.000 Webinar. And I'll also remind everybody, if you joined us late, there is a unique seminar homepage. You can see it in red on the slide. It's also available through the QR code. That website will remain active from today forward. It is where we have posted the presentation materials, copies of the framework, links to the videos. 01:54:46.000 --> 01:54:57.000 I will be adding in some of the additional references that we included in the meeting chat, such as the link to the Northridge Estates and the additional research paper that was put in there on the vermiculate analysis method. 01:54:57.000 --> 01:55:09.000 So make sure you bookmark that and reference it. You can also share that link with others. And for those of you looking for participation or certificates for joining us today, you can get one of those by filling out our short online feedback form. 01:55:09.000 --> 01:55:23.000 So if you go to the seminar homepage, scroll down to this section on feedback and fill it out. Once you submit it, making sure you check the box at the bottom of the form certifying you were here for the entire live delivery. As soon as you submit it, you'll then have access to download or print out a participation certificate. 01:55:23.000 --> 01:55:31.000 If you hosted a viewing party and I saw that there were five of you out there who did, which meant a group of you collected together in a room to watch this together. 01:55:31.000 --> 01:55:39.000 Whoever signed up, simply send the people who joined you the link to that homepage. They can each fill out their own feedback form and get their own certificate, even though they didn't register on their own. 01:55:39.000 --> 01:55:48.000 And please know, I read each and every one of those forms and I really do count on your feedback to help improve and continue to offer free technical sessions. 01:55:48.000 --> 01:55:59.000 Like today's webinar. Today's session was recorded and will be automatically archived on the Clutin webinar. All registrants will get an email from me as soon as part one is available. It usually takes me about a week or so to post that archive. 01:55:59.000 --> 01:56:09.000 And if you happen to be one of the lucky people that have made it this far and are watching the recording from today, you too can share feedback and get your own certificate based on replaying the archived webinar. 01:56:09.000 --> 01:56:18.000 Right about now in the recording above my head in the upper right, there will be a button that will take you to that same feedback form. You can fill it out and get your own certificate based on the replay. 01:56:18.000 --> 01:56:24.000 With that, again, I want to thank our panelists, our organizers, and those of you who joined us for today's live broadcast. 01:56:24.000 --> 01:56:27.000 And I hope to see you all back here tomorrow at 1 p.m. For part two. 01:56:27.000 --> 01:56:30.000 This is the formal conclusion for today's live broadcast. Thank you so very much for joining us. 01:56:30.000 --> 01:56:37.000 Yeah.