 Good afternoon everybody, hope everyone had a nice lunch. This morning we heard a lot about the history of work at Owens Lake in terms of death control development and regulatory history and operations and maintenance. This part of the presentations are talking about key constraints and considering alternative death control measures. So I'm just going to introduce it and then I'm going to hand it off to Phil and Ann to give the rest of the presentation. So we have Ann and Phil. The things I wanted to cover for the district and our key constraints are provisions under the Cleaner Act section 172 and this is specific to no backsliding. And so what this requires is a continued progression for the plan. And the place where we're at now at Owens Lake, we have a plan where we feel that we can reach that attainment designation. We have the provisions in the security judgment, we have the provisions in the SIPP, we have additional back-end contingencies where we can actually make that progress towards attainment. The designation of attainment is basically three clean years in a row where you can't have an exceedance of the next more than once a year on average over that three-year period. So you could have three years if you couldn't have any of the next two, you could have one a year for the three years. We're not there yet and we have some challenges ahead, some little pieces to clean up. But that's a really important part of the key constraints that we can backslide on that progression. We have to maintain the control efficiencies and back-end requirements for the currently controlled areas. And as I think a lot of the presenters have already touched on today, just maintaining the operations, the infrastructure, the required to meet the performance criteria, the performance criteria of back-end, making sure there's quality, if quality misindex is enough, making sure that it's roughness is good enough, doing the maintenance, having reflit orders, these are a lot of work as it is. So another component of this is the development of newer modified test controls. So there's limitations on the testing. As new as modified controls, there's limitations for whether or not you're going to do a shallow flood refinement test, or whether or not you're going to do a back-end test, or whether or not you just want to do some other tests to find out how effective a control measure may work. You can do a pilot study test in a sense of resource area that we've got ideas for. And then once those tests are done, there's other important considerations like the demonstration test, what the success is, what the durability is, what the reliability is, how long it can persist. These are really important key constraints for us. Back sliding. So as Grace mentioned, the requirements of back-end and its emissions reductions, the clean air requires that all best-available control measures and all best-available control technology need off to different sources and PMTN attainment areas need that 99% control efficiency as specified at all times, day and night, winter, summer, hot, cold, wet, dry. And those performance standards have to be met. There are provisions for variances or circumstances that are outside of reasonable control of DWP to the brief breakdowns. But yeah, there are still limitations to the variances. If it can't go for more than a year, that should be approved by the hearing board. We've always had greater success together. The district and the DWP are on the same page requesting for variances. We can, under certain circumstances, require tests or request tests from DWP and we've done that with Diana Water Management. The compliance is a certified evaluation of the performance standards and each and every one of those desk control methodologies at Aung Lake have very strict performance standards. A lot of them we still find challenging to achieve shallow flood weapons requirements for sprinkler areas. We had an overpass a week ago or so and some of the areas that seem to be working very effectively meeting that compliance requirement were at 56%. So you're almost 20% below that required shallow flood requirement just because of the temperature and the soil types and conditions and the ability to distribute that water and the frequency of that SCADA system or sprinkler systems coming on and on. So, those are things that we have to ensure are met. And then one of the other things about the no backsliding and vacuum requirements is that there's specific provisions that the vacuum has to be approved by, that I'll push me to officer myself. And to get my approval it's very tough. They didn't have to call my staff first. So, you know, the, it moves in a chain of command and it has to work to remove the experts in that field and testing in the scientific endeavors that are performed. Then once, if it's workers you might have approval it has to go to the district governing board or legislative office. Or once that gets approved then it would have to go on to the California Air Resources Board for approval. And finally it has to go to the US EPA for approval. And to date EPA has never approved any of all our modified back-ups or amendments to our SIP. They've only approved the 1998 SIP with the shallow flood, gravel and vegetation. And then they approved the 2016 SIP and the provisions of that as well. So, that was I don't want to underestimate the monumental achievement of that 2016 SIP and getting the EPA approval. It was a lot of work a lot of criticism Sacramento, a lot of networking with CARB and DTA and DWP running the termination test for shallow flood periods for the dynamic water management, getting brine in there and tillage from the security judgment, getting that support from our agencies that oversee us that these are actually going to work because they aren't the experts in the field. They're great based in their district and our staff. DWP as well working in these environments all the time that bring that to CARB and EPA. So, yeah, we're confident enough that 99% we support this and then EPA approved it. At that point then of course our SIP was in a regulatory freeze with the new presidential administration. So, there were the 40 regulations that were frozen in January 2017 and our SIP was there for 60 days before the thaw and then the EPA approval went through. So, that's significant. I forgot to mention earlier so I wanted to bring that up. But still is discussing for anti-backsliding provisions in the 2016 SIP as well as the regulatory documents that accompany that. There were really specific provisions that were included for the development of new and modified dust control. And I'm going to try to present this in a way that leads to the PAM. I'm going to be referring to as backum development and the other I'll be referring to as alternative dust control development. And as I go through this hopefully those two paths are clear. And they're not mutually exclusive but starting with best available control measures the efficiencies are required for areas that have already been ordered. And so for the anti-backsliding provisions those areas need to maintain those control efficiencies. And so to do so with consideration of new dust control they need to be held to a high standard. And so for new best available control measures there has to be a demonstration that sufficient PM10 control can be achieved and maintained under all conditions. And it has to include a margin of safety for the different environmental conditions that can occur on the lake. It can't be done in current ordered areas. The backum for a currently approved backum has to be maintained. And so typically when different dust controls are being considered it would be difficult to maintain the performance standard of an existing backum while testing another not to say that it couldn't be done. But it's a limitation on the testing within current ordered areas. There's also some specific provisions about where the best available control measures need to be applied. In general the testing that's been done has been for use across the entire lake. But there are provisions that would address if a dust control were to be limited to specific circumstances. So a backum that was for specific soil types or some other environmental conditions. And similarly to modify or adjust existing backums there are some specific provisions included in the stiffen board order to talk about the duration of the testing and address specific types of testing. So there are some requirements for shallow flood wetness cover refinement field testing as well as for testing the reduced control efficiency of shallow flood and managed vegetation. And so testing of or modifications and adjustments to existing backum the parameters for that is outlined in the regulatory documents. And on the other hand we have what I'm going to refer to as alternative dust control. And that would be dust control that would be developed and utilized outside shown here on the map. So areas outside of currently ordered areas do not need to meet the performance criteria of backum. And so when we talk about alternative dust control it doesn't necessarily mean that dust control couldn't become backum it just potentially means that it hasn't gone through the rigorous testing required for backum consideration. Alternatively it may not be appropriate to become a best available control measure. So it could have a lower control efficiency, less rigorous performance standards. Potentially because of that it would have less disturbance and engineering to implement. And so that could be appropriate for environmentally sensitive areas used as temporary transition areas. There are provisions that allow one type of dust control to another. Some such as moving from brine or tillage to shallow flood. The performance standards can be met continuously. Others require that the performance standards are not met and if they're not met the city is only allowed to transition three square miles at a time. Alternative dust control would also be appropriate for unordered lakebed sources or potentially off lake sources. So this doesn't take into consideration other agencies requirements but from an air quality standpoint the two main constraints would be anti-backslide. Tainment made towards PM10. Tainment as well as the limitations on development of backum. Okay so next and I think we have up Jennifer Wong from wrong one. She's from L.A. Department of Water and Power and then we'll move to questions for the panel for you. I'm with the Capital Development Implementation Group within the Olens Lake Dust Mitigation Program here at DWP. I'm going to be talking to you today about regulatory constraints, obligations and considerations and how that impacts development of future capital projects. Before I jump in just a little bit of background on me. I joined the Olens Lake Group in 2014 and have a team construction of Phase 7A, Phase 910 and I'm currently overseeing the planning of Master Project. Before I came to this group I've been a civil designer, a structural engineer, I've been resident engineer fighting contractors in the field and project manager doing bridge projects in the city of L.A. and I got to tell you no matter what challenges I saw on those projects working on Olens Lake has been truly unique. With all the different stakeholders our goal is always to deliver a project that meets everybody's needs while conserving every last drop of the precious resource we call water. So with that let's jump in. The agenda today I'm going to take you through a consolidated rule book that we consider when we develop our new project. Talk a little bit about property ownership, the Olens Lake Advisory Committee and what exactly is Master Project. In general, to consolidate everything we have several rules that we have to meet. So first off we have to achieve less compliance standards that's why we're at Olens Lake. We have the SIP as our guiding document when we consider new projects we look to the SIP for the different criteria for the back home whether it's brine, shallow flood, tillage, gravel we also consider the transition limits, three square miles at a time the district doesn't want us taking more out because obviously the more areas in construction at any given time the more potential dust emissions we also have to maintain habitat and when we say maintain habitat what does that mean? Before we started doing dust mitigation these ponds that we put in were not there. So slowly over the years we've added water and the birds have taken the liking to Olens Lake and so as a group of stakeholders we've come together and we've noticed that the habitat that was on Olens Lake between 2012 and 2014 is considered the baseline habitat and when we talk about maintaining habitat that's what we're referring to we also need to make sure that any project mitigates impacts to cultural resources. The first 10 projects we had the district would give us an order and we're out there doing work on wherever they told us to because that's where we have to make dust emissions. It doesn't take into account the possibility of tribal artifacts that we may find. We do have an opportunity if we know a site is eligible before construction to get it removed from a project but a lot of times until we start construction we don't know if we have eligible or ineligible archeological sites. So what happens during construction a lot of times is we find these sites and we end up having to design around them during construction. We keep going to stay on schedule so that we meet our dust compliance date requirements for the district and as archaeologists are deciding whether or not a site is eligible or ineligible we're finishing the rest of the project. If a site is deemed eligible we're able to remove it from that phase of construction. If it's deemed ineligible we're required based on SIF and different orders we've had to do some sort of backup within that area. One of the challenges to that is that even if a site is deemed ineligible a lot of times it is still significant to the tribe and so we do end up having to get creative and work out solutions to make sure we're not impacting cultural resources. The state as Phil mentioned owns the majority of the property which means the lake is a public land and we have to make sure we're upholding the public trust value. We'll get into some detail on that in a little bit and obviously mitigate any other impacts to environmental resources. Property ownership just to break it down simply we have this map on the right. The tan area represents California State Land Commission property. The light blue water and power owned property. Then we have the purple and light blue dark blues that represent private property owners. The way that affects us particularly during construction is you get cases like you have here on the left. This is a dust control area we call T21C that we built under the phase 910 project where I know a lot of you've heard of the four corners of America and the four corners of the United States have owned lakes. At the top we have the duck club, privately owned place for duck hunters to go during duck season. During construction we have to keep noise levels down or else we're scaring off the ducks. On the right we have BLM property. BLM is federal land so instead of doing the environmental impact reports under the California Environmental Quality Act, NEPA applies to the National Environmental Protection. On the bottom we have CD Rock Sand which is also known as Crystal Geyser. Crystal Geyser does not allow us to put fertilizer down. So you can see the distinct difference between the California State Land Commission property and the CD Rock Sand property and how well vegetation is doing. California State Land Commission in keeping up public trust value does not like for us to have too many straight roads because that is not natural looking. They require us to make roads and back and boundaries as sinuous as possible. So that's why you see that road kind of looking like a snake. So with all these different stakeholders we do. We form an advisory committee. I think in about 2010 groups representing interest and dust control, water conservation, habitat, cultural resources public access, education, recreation agriculture and business came together and formed the advisory committee. The advisory committee's primary goal is to provide recommendations to DWP on how to implement future capital projects. The number one goal is to manage natural resources through monitoring and adaptive management. That's where the concept of master project came from. We developed this master project framework. The advisory committee was broken up into several subcommittees. There are three groups and then another group that feeds in that I'll talk about. The first subcommittee we should talk about is the Habitat Work Group. The main thing that came out of the Habitat Work Group was the Habitat Suitability Model. Prior to the Habitat Suitability Model it was considered that an acre of shallow flood anywhere on the lake technically has Habitat Value. What the Habitat Suitability Model was it put in quantifiable terms Habitat Value for different guilds. Basically it said that if you for this guild have a certain percentage of islands, percentage of water that's six inches and a target of salinity levels then that Habitat Value is actually much higher than it would have been if you just had an acre of shallow flood. This model has allowed us to take some areas and convert them into non-water users. It allowed us to put in water, allowed us to do tillage. Looking forward towards master project basically the basis of what master project will become. The Habitat Suitability Model feeds into the resource protection protocols. Next we have the Groundwater Working Group. As part of the master project we're considering the use of groundwater below the lake as a source of water to mitigate dust. The Groundwater Working Group has recommended RPPs as well for the master project and is currently putting in the Ideologic Monitoring Management and Mitigation Plan. Also known as the HCCMP. Then we have the Public Access and Recreation Work Group. Their work has been completed. Back in 2014 they put together their recommendations and much of what they recommended was built during the Phase 7A Project. On the right here you see the T30-1 Plaza. It's a beautiful place to go. People go out there to do yoga. I think I've heard of people having weddings and all kinds of things out there. This is basically what the culmination of their recommendations. There's a couple items that were not completed and considered as part of the master project as well. Lastly everybody is also considering public resources protection. As we look toward the master project it's a water conservation project where we're taking all of our existing dust control areas and potentially turning them into more water neutral forms of dust control. But we have an option up front to not go to certain sites that we know have high likelihoods of tribal artifacts. So it's not like an order it's something that we can choose to avoid certain areas. We're doing our best in the planning phase to keep the tribes included. There's also something happening in the background where it's a district nomination where the entire lake is being nominated as a archeological district. That'll come with its own management plan incorporated into any environmental documents in the future of the master project. During construction we lean on our mitigation monitoring and reporting program. If you have to summarize the master project goals we want to mitigate dust emissions in compliance with governing air quality regulations. We want to reduce water use to the greatest extent possible. We want to protect cultural resources. We want to maintain habitat value. We're looking at replacing aging infrastructure and maintaining public trust value. In addition to the recommendations that we got from all of our stakeholders, we have taken a look inwards. We've talked a lot with our operations and maintenance folks our boots on the ground that really know how things work out on the lake to make sure we're addressing their concerns and using their feedback and development We are taking a strong look at aging infrastructure ways to enhance efficiency and flexibility We need to improve pond metering, instrumentation, communication and control systems. The operators even have given us site specific recommendations where they check all of these 160 different dust control areas and said, hey, these are the ones with soil that's the best for tillage. Over here we have sites that want to become brine Let's let them go to brine. It's very salty. We have gotten feedback from them on the latest meter flow data and we want to make sure we're using the right numbers in planning a future project. We have to know what each site uses right now to be able to tell if we're going to save water in the future. And of course, apply lessons learned from previous projects. We also work closely with our own biologists in optimizing habitat value acres by way of that habitat suitability model. Our goal is to maintain lake-wide habitat for all of Guilds. The biologists have told us that we really got to figure out salinity management in a big way For us that does mean some new water in cases where we're creating habitat ponds because salinity management obviously takes a lot of water. If you have the lake, the majority of it, which is salty and you're trying to make it fresh water for birds and other wildlife then you're flushing constantly to get that salt out. The biologists have also told us, hey, in areas where we have good habitat, let's not mess with that. Let's not try to convert that to anything else. Let's leave it alone. They've also mentioned that some Guilds benefit from summer water Right now we don't have summer water requirements or we didn't before dynamic water management, but now by adding some summer water, areas that previously would not have water because the dust season was over during the summer, would now have a little bit of water in the summer. That creates some challenges for us because summer is typically when we do a lot of our operations and maintenance. This table down here on the bottom is probably difficult to see, but this is a list of generic prescriptions that our biologists have put together where on the far left there's the different Guilds are listed and they have basically calculated what depth each Guild like. So what percentage of each site should be by, for example, what percentage should be between 10 and 25 centimeters? What should be over 40 centimeters? They've also told us what the target salinity should be for each Guild. Island proportions, drier proportions A lot of work has gone into this. They've also on a separate worksheet put together custom prescriptions for very specific sites where we know it's going to be a mix and match of different types of back-em. So putting all of that together has been a small feat, but ultimately we put together a computer algorithm and we've had numerous workshops and certainly we've come up with a project and so this takes into account all of the different stakeholder feedback the feedback internally and looking forward we have a construction project on the horizon. We're still running cost benefit analysis on it to make sure it pays for itself over time but basically this isn't where we're at right now. So we have two areas two high habitat areas that are going to be T29-1 and T13-2. This map on the right here shows only the areas that are going to be changing under this master project. We have a lot of projects that have previously been converted under the framework but you can see here it's a little tough to see with the lights on but you can kind of see the different sites that we're proposing to change. Anyway, about wrap it up for me. Thank you guys. Thank you. So if we could get all the speakers from the last two presentations in the morning and these two most recent presentations to come up. I'm going to open it up to questions before I open it up to questions from people in the room. I'm going to ask people on the phone. Do you have any questions for the speakers? Yeah, this is Scott Tyler. Just a couple of quick things for a variety of the speakers. So thank you to all of you. I appreciate the information. A question just sort of an overarching question is what is the water consumption that's currently used? What's the annual amount of water that is evaporated that is Owens River or I should say freshwater that's being supplemented to give us a sense of volumes? So our latest numbers have us at approximately 60,000 acre-feet per year. That's with the implementation of several master project framework projects to date. The year-to-year basis I think we have 45,000 acre-feet in 2015, 75,000 so it does vary even though the average is about 60,000 acre-feet. I think the 2015 number is a little funky because we had several areas that were in construction. We had tillage coming into play while we had phase 7a so the water numbers were pretty low that year. And then just a clarification question from my side on the 3600, this was brought up early on, I think I understand it, but the 3600 foot elevation which is the historic lake level at the time of beginning of desiccation if you will, that's a regulatory number. That doesn't have anything to do necessarily with true lake level, is that correct? That is correct and it has actually now turned the regulatory shoreline we've changed from the historic shoreline which was used in the previous SIP documents. I appreciate it, I think that's useful for all of us. I guess just sort of the last comment is more of a comment, but I appreciate the couple of speakers talking about it and that's the question of salinity at this site. All salts are not created equal from my perspective and I think it's important for all of us to think a little bit about why is this lake producing so much dust if you haven't been out there before compared to the Bonneville salt flats and other places that don't produce dust and it's really the chemistry of the dust or the chemistry of the salt surfaces and the salts that are there that really play a dominant role in how the system behaves and why it's as dusty as it is even though it's a fairly modern pile lake. I think that's just something important and I appreciate it, I think it was Grace who brought that up talking about what the chemistry of the salts are that are fundamentally different than what we might think of as just your salt, just from my perspective. That's all I had, thanks. Okay, Dr. Ben Capram. Yeah, this is a question for Alan Logan. How do you measure the effectiveness of these control measures? For example, tillage. How do you know how effective? Are you talking about in the development of approval for the backup or once it's approved? How do you measure the relative effectiveness of this? How do you know, for example, they talked about 99% effectiveness. What does that mean in terms of, I still the soil and then how do I know it's controlling dust and to what extent? The best available control measures underwent testing before they were approved by the district and then 99% control is the control efficiency. And then the conditions are reduced by 99%. So for tillage specifically, the city of Los Angeles did testing in an area on the lake called T-12 and originally tested it for tillage to be approved as a backup with no backup. The district only approved it as a subset of shallow vacuum flooding provided that the tillage was a backup of shallow flooding. And so it underwent several years of testing during which time the control efficiencies were measured through the dust identification program, PM-10 monitoring from which the parameters that are the performance criteria were developed of the characteristics of the test, which is where we get the roughness criteria and the sand block measurement. So each backup has different testing to develop the performance criteria. When you describe this in detail somewhere describe somewhere this testing procedure for example, how do you know it's a factor? You said it has undergone a lot of testing so describe somewhere? Yes, there are documents that describe the testing that each backup has undergone and then the 2016 SIP and the board order describe the provisions for future testing. So why do you do the induced particle emission test using drone? I mean that was a strange thing. Could you explain what that is? Sure. So the iPad test was a way to induce emissions by downwash of the rotors of the UAV so it's creating basically artificial wind on the surface and there are criteria for which height those emissions are created for maintenance levels and reflood. I just wanted to add something briefly about the iPad. So a lot of the performance criteria for TWB Squared as well are actually reactive tests. So you've already measured PM-10 you've already measured sand flux, the arming isn't working, the roughness isn't working so you have these elements where you aren't achieving backup you aren't achieving emissions controls but it hasn't been windy for a month and so you're under this false impression that it's actually working and it's not. The iPad test is the only test we have actually proactively go out and test the surface to see if it has that durability and control effectiveness of the tillage so it's a valuable tool and it's a unique component to that performance criteria testing. Let's move on to protein. Okay, I think you described the number of monitors and just the quantity, right? So I was just curious how do you decide on the location of the monitors? One question here you, the second is is this continuous? Is it a certain sequence? And maybe I'll finish my question so I save some time on other metric measures, for example, met data, meteorological data, wind speeds, wind directions and even PM-2.5, like I think it's passing you mentioned is the data of a lot of data. Sure, so most of these monitors are continuous. The primary monitors used in the network around Owens Lake is a 1400 tl So we do have filter based monitors in communities primarily Just how do you locate, where do you locate? Sure, the monitoring network locations were selected over time to help identify sources on the lake so they encompassed the regulatory shoreline and then there were monitors placed on the lake to further refine locations and that because installation and monitoring a PM-10 site, especially to EPA criteria is a very expensive and time consuming endeavor, that's why the death identification program was developed which is monitoring a horizontal sand movement so that in combination with the ambient air monitoring all have to go into the identification of source areas for control and all of the PM-10 sites have meteorological monitoring there are several additional sites that are just met data only the primary variables of importance are wind speed and wind direction because that's what drives emissions on Owens Lake but temperature, relative humidity, barometric pressure are also measured at some sites. PM-2.5 in Keeler It's in compliance this much No, but we are unclassified for PM-2.5 designation I have one question for Arash So you mentioned about the baseline, sorry the fertilizer using fertilizer in one site versus the other site Underneath one place, so are you guys like testing while you're using these fertilizers? Is this impacting your groundwater quality or is this actually a part of the discussion and I'm asking you because then if the CDROC sand right, that was the name, if they are depending on the same groundwater basin, that's why they don't want you to use fertilizer the groundwater between all connectives, it doesn't matter if you put it on Right, I think we're the amount of fertilizer that we use for our managed vegetation is minimal. I don't think there's any concern on our part that we're impacting the groundwater supply. That location although that's where you see the CDROC sand property where they're pulling the water from is actually quite a bit of waste So that's their processing facility? The offload probably quite a bit of other materials that they're pulling out of the water and they're doing their own thing over there that's probably far worse than anything we're doing And then I had one other question with Jennifer, you mentioned the tillage and I think you sort of touched on that the maintenance level for the tillage is very very low Right, you put it there and it's great That's as long as it's performing and meeting the backbone criteria that Angela's mentioning about, but should there be an issue where especially dependent on weather conditions, certainly high wind and rain can negatively impact the integrity of the ridges and that's not to say that the area is going to be omitted, just to say that it won't meet the criteria for ridge hypes and so it might melt down and it's also very heavily dependent on soil type as well, because I think, I forget who mentioned, but the tillage areas, there's a range of soils, it could be clay, it could be more sandy so then obviously they're still all held to the same criteria, so there are times when there is some kind of segregation of the ridges and it'll fluff off into the furrows, which the job of the furrows basically is to also help catch any of that sand that's either coming from outside the area or potentially catching that material that's being fluffed off from the ridges so the purpose of us going through the existing furrows to push up and out that same material back onto the ridge hypes and really, we always try to be preemptive in any type of maintenance, certainly we don't want to get a nasty ground from Ann or Bill definitely, we don't want them to have to tell us to do our homework, we should be able to have eyes on the ground and that's what we do, we have eyes on the ground who are monitoring the health and also part of the requirements and monitoring, there's just people out there all the time checking on these areas and then so depending on what they see, I think we've developed a very good relationship with the district in that way, especially with Nick Barbieri who's not here right now, but he's actually kind of the lead on the district side for being in the field, so there's a very good relationship there where we can talk to each other and say, hey, we're noticing that there are some areas that maybe need a little bit of work, what do you think, schedule a field visit out there and then depending on what is being recommended to us by Nick and the guys out in the field who know best, they'll determine what level of maintenance we need to do, so it could be simply as going through the existing first, it could be telling the inner road or if more is needed then we're going to have to go up to the next level, we're just leveling it, retailing or flooding it. I have one more question on this which is you have a lot of different kind of infrastructure there, going down the list, which one of these backends have the least amount of infrastructure, the man-made infrastructure but they have the highest effectiveness, and I know you might not have measures out there, but just on top of your mind trying to figure out like how, well you know, and I required less sort of, which I'm getting at this like then required less amount of repairing after rain events or flood events or something like that that you can quickly sort of maybe bring with you equipment and make it work again rather than. I think, well definitely, the back-end types have the least amount of infrastructure would be our gravel areas because simply we don't have really any infrastructure out there, right? There is some drainage through some of the berm roads and in terms of gravel maintenance we're certainly able to respond and we have, and I think in my picture I had different mechanisms, mechanical mechanisms to be able to basically kind of like do maintenance on that area, but I would also say brine areas because you know the lake naturally and you know when you guys see that map with that big brine tool in the middle a lot of the, I mean the lake will do what it wants to do and a lot of areas naturally want to go towards the briney side. So you know we do have currently existing brine areas. There's other areas that are shallow flood but certainly you know are tending more towards the saline side. So I mean you know we would prefer to let the lake do what it wants to do and that is over time you know become a brine area potentially. Thank you. Greg, then Roya, then Scott, and then we'll cut off questions. I'd be interested in talking about some of the detailed stuff that I said in 10 plus monitoring and other things, but I don't want to take the time in there. I'd rather use kind of to ask a sort of a big picture question which is it's clear that there's no one thing that works every place, right? And it's clear that there's no one thing that works at all time if you think of an inter-annual landscape, a long decade of landscape. I'd actually like to hear from each of you in your opinion what's not working. What's the biggest thing that needs the most that is the most dissatisfactory for you for some reason? So it might be, you know, I'd like to know which is the most dissatisfactory matter. We call them love letters by the way, not nasty. I won't do that next time. So for me it's the things that keep me up at night. And those things are sometimes unknown, but they're the things that you have concerns about. So it's tillage areas that maybe aren't quite meeting the performance criteria that they expect and they're changing or a specific event changes out like a rain event. And so that day it may be tillage. The next day, if you had a fire in a managed veg area there is no veg and so that area becomes completely emissive. So it would change that day. What we've experienced in the past, we had a jet crash in the shallow flood area. And within 15 days that became the largest source on the lake, causing excuses and keelers. And so it was that shallow flood area. You think of gravel, gravel the end all until you have the inundation. And then that inundated sand or that blow sand then becomes a source. And so they all each and every one of them have their own impacts and then kind of vulnerabilities. And so for me it really does change. I'll mention two things. One, I think Jaime touched on it in his presentation in sprinkler shallow flood areas. A lot of times we know the area is soaking wet. But when the satellite flies over it does not hit 75% wet. The operators and maintenance folks go out to the field. They sink into their knees because the ground is so saturated. Yet that area is not considered compliant unless we're hitting our 75% wet targets. I think another item is probably the 95% confidence interval for managed vegetation where we have other measurements. Are there certain areas that are compliant if you take away that 95% compliance interval suddenly are not compliant just based on that strict requirement? Actually I think for me I think well I guess there's two things but a lot already touched on the use of sprinklers, sprinkler shallow flood. You don't necessarily have to have super saturated soil to evade dust. We feel that there's a range of soil moisture that can do the job. But we don't necessarily get credit for that. What we do get credit for is the satellite that goes around every day and what that picks up. I think part of what Influence is, what the witness coverage is is also soil types. I mean we have some like solid soil that for some reason you could go out there, it's wet, there's one area like T184. You have these really salty soils and you think it's going to pass but then it doesn't. And then it's like what the heck is going on here? So trying to understand like why is it not necessarily working out in the field? Like you can be on the ground and you can see it, it's wet but when it shows up on the satellite imagery it doesn't. So what are those factors that are contributing to it? I think it's very important to kind of better understand that and also range of the soil moisture. I think also for tillage, I think it's very important. I think as you guys saw there's a lot of long criteria that will dictate whether or not a tillage area is compliant or not. There is room in the stipulated or I should say in the stipulated judgment for revision to those thresholds for compliance. I think and definitely I don't mean to say I think working with a district there's been plenty of times where it technically failed but we work together and they haven't issued us a reflood order. They let us do what we thought would work best for that area but I do think that there is some room to kind of take a look at those super conservative thresholds and really understand how is tillage working? I think like when we talk about some of the ridge height and ridge spacing and whether or not it's working or not like I think tillage does work even if it doesn't give you that ridge height because I think stuff gets trapped in those furrows and it's not leaving the site. I mean if you're trying to gauge whether or not it's admitted as the regulatory shoreline is it picking up from these tillage areas? I think for me I think that's one of the biggest things that would not let me sleep at night is just thinking about some of the conservative criteria and being able to work together to maybe make some refinements that better match what's actually happening out in the field. To carry on from what Jennifer is saying I think for me providing the alternative perspective there are probably no performance criteria that are too conservative and I understand from the city's perspective that that's frustrating in terms of operation, maintenance, the field staff who's reporting that it's working but it's not meeting a performance criteria but from the regulatory perspective the performance criteria are it's a fine line because we have to have confidence if they'll work. It's still discussed earlier if we have emissions from tillage or sprinklers which are my two primary concerns it's too late. We haven't demonstrated the same thing. In terms of refining back home, developing new back home it's really important that those parameters don't get pushed too far that we're having emissions, having exceedances. So in development of dust control it's important that the testing is done such that there's a margin of safety for the environmental conditions that cause exceedances and most of the time those conditions don't exist and so there aren't emissions and so it can seem that the criteria are too stringent when in fact perhaps they aren't. Okay let's move on to Roya for a quick question and then Scott for a quick question. Sure thanks for the opportunity. So I guess my question is related to some of the things that have been discussed so far but they like to clarify something. If I understand correctly different back homes are in place because different surfaces have different emissivities and each back home basically gets tested before it's sort of at the larger scale but for exceedance situations we're going by PM10 monitors that are along the shoreline right. So my question is during the times that there are exceedances is there a way has the district looked at different ways to sort of decipher that data and try to understand which areas and which back homes are the ones that are not maybe performing to the expectations basically. In terms of analysis of monitored federal exceedances areas that are under control are not currently contributing to those exceedances. That there is an evaluation done to ensure that that doesn't happen but the exceedances tend to be caused or contributed by areas below the regulatory shoreline that are not controlled off lake sources and sometimes regional events that move into the PM10 planning area. Do you have a sense of what the proportion of those different categories are which is most important? That varies annually so different neurological conditions can create different types of exceedances but I'd say as far as the trend we've moved from the majority of exceedances being caused by sources below the regulatory shoreline to now below the regulatory shoreline the magnitude and frequency of those exceedances has significantly declined to less than a dozen a year. But still the standard is one per year. And off lake sources are now higher in magnitude than on lake sources. Quick question from Scott. A quick question and then a comment. For the term durability time and time again yet there's been no hard time scale what's considered to be durable as far as the treatments are concerned. That's one of the things that's in our task statements we have to be able to assess according to durability. Ideas on that from both parties. I think it depends on what perspective you're coming out with the definition of durability means. If you're looking at the operations and maintenance it's probably just a cost to benefit for the amount of time that you can get out of that dust control you put into place. So you put in tillage versus gravel potentially the durability of gravel is significant in that of tillage. However gravel is putting in a place where there are other off lake or contributing sources and it's in a day to withstand and the durability is next to nothing where tillage then can actually absorb some of that inundation and then it lasts longer. And not just in durability isn't like the physical properties of something but the durability is in that dust control being able to effectively control emissions. So like Chanel flooding that's meeting 75% wetness. You meet that 99% control efficiency requirement and it's very very effective. We don't measure any emissions. Very successful however you turn off the valve and within six or seven days you can have emissions. So the durability of that dust control if the infrastructure isn't in place is very minimal. However the long-term durability of it as a dust control method has been very successful because of the availability of water infrastructure that's been put in place. So this is a challenging question to answer. Alright just to add to that most of our projects to date most of the orders that we got had very tight timeframes. Really quick turnaround where we had to put together a design we'll first get a design ground board, put together a design, get it out to bid an award, do construction in about a year and a half on these massive dust control areas. That didn't leave a lot of time for considering what's best for the lake, what the lake wants to do itself. It's whatever we can do let's go do it before we get a fine from the Great Basin. So for years it's hey we're out there while we're in construction in one phase we're already in design for the next phase maybe we'll catch the lessons learned by the phase after that. Now we have about 20 years of doing this we've got a lot of lessons learned we have a chance to take our time with some of our designs Jennifer mentioned it let's look at what the lake wants to be and as we look towards Master Project we are considering that. That big effort from our operators to go out there and say hey this is a great site for tillage. The soils are going to stand up here you know clay you're going to get great clods versus this site over here let's never put a habitat area here because it's so saline so briny and if we ever want to do tillage we couldn't even get equipment in there. Listening to the lake you know as cheesy as that sounds is really kind of what's going to drive our durability moving forward. As phases have progressed we've put in we've shifted materials we're using a lot of like stainless steel HDPE plastics corrosive environment does not help right it's destroying our infrastructure little by little but the operators and maintenance folks really have gained a lot of experience we've gained a lot of experience from our project and we have to incorporate that into whatever we do from now on. Okay so thanks to all of our speakers we're going to need to move on before we move on.