Day 3 - Marine Carbon Dioxide Removal Standing Committee: Meeting 2

All right. Um, everyone, welcome back to the third day of this meeting series for the Nationalmies of Sciences, Engineering, and Medicine's Marine Carbon Dioxide Removal Standing Committee. My name is Kelly Obig. I'm a senior program officer at themies um in Washington DC and I'm serving as a staff lead for this activity. So, please note that this is a public meeting. It's being recorded and the recording will be posted on our website in a few days time. If you are joining us for the first time, um you can find out more information about this project on our project website. Um Safa will put a link to that in the chat. Um and you can also view the recording from our first meeting for additional project details. Um let's see, next slide. So this is the third day of the meeting. Um we've the day one we went over kind of the ocean's role in climate mitigation, the state of monitoring, reporting, and verification. And then we had a series of lightning talks to just give us a snapshot of some recent advances in the field. Um the day two yesterday we talked more about MCDR policy and permitting and also social perceptions of MCDR. Um and then today is really focused on um some recent work in laboratory micosm and field trials for for MCDR. So, we're interested um in how these trials were designed um what are the observation and modeling requirements, community engagement efforts um and efforts made to assess efficacy and environmental impacts. Um we've got five speakers with us here today. Um Aaron Ferer from National Oceanography Center um will be leading us off. Um Aaron, the floor is yours. Oh, actually before I give it to you, Erin, let me just say that um we're going to go ahead and get through the five presentations and um afterwards we'll open it up for uh questions and answers. Um we have plenty of time today. We have a full two hours if we need it. Um so, you know, prepare your questions and we'll use the raise hand function um to ask questions. We do prioritize questions from the committee, but we should have time to get to everyone today. Um, you can also feel free to to add um questions to the chat. Okay, now I think that's all I needed to say. Um, Aaron, welcome. >> Thank you. Um, is my screen showing? Oh, not yet. There it goes. >> Right. Oops. Sorry. Um, yeah, thank you for having me, S. Give me this opportunity to speak. Um, so I'm currently working as a research scientist at the National Oceanography Center. Um but today I'll be talking more uh about the work that I've done at the University of Tasmania um and part of the broader group there. Um yeah so my role in this group is largely focused on looking at the impacts of OA um in terms of um its impacts on coastal phytolankton communities. So through lab based experiments, microcosm experiments and then some involvement in the miscosm experiments conducted by GMR. Um yeah and so at UTAZ we started our experiments back in 20 oh sorry there we go. Um we started our experiments back in 2021 with the microcosm experiment. And the focus of this initial experiment like many of this early work was just to sort of have a look at the influence of a relatively large change in carbonate chemistry on a coastal plankton community. Um we know now that these really big and sustained pertubations of the carbonate system are pretty unlikely to occur in the real world applications. However, this was a really good starting point as it increased the likelihood of us observing the impact um and thus enabled this early work to sort of identify any potential processes um and or phytolanin groups which may be uh significantly impacted by OA. Uh so we did focus on OA related changes in carbonic chemistry alone and this is largely because it was and still is somewhat unclear as to the method of OA that's going to be utilized in the future. Um and this is important as it ensures the findings of this early sort of work are at least somewhat relevant. Um as all these methods are going to sort of result in a change in seawater carbonate chemistry. Uh so this initial experimental design was pretty successful for us. Um it enabled us to identify some key processes which were um impacted by OA. Uh namely for this first experiment was the change in uptake with dissolve silicate uh which you can see here. Um so this led to several reiterations of this same experiment um with relatively minor adaptions. Um so just sort of trying to shift our focus to specific areas of interest and narrow down um areas of interest following prior results. Uh for example, my colleague Joing did some work looking at steel slag and olivine and this largely came out of some work done at Southern Cross where they found that uh steel stag was quite efficient increasing alkalinity and Jaing's work showed that it was also um resulting in relatively minimal environmental impacts. Um and then we also had a master student who used the exact same methods that we used back in 2021 but instead of focusing on the biogeeochemistry she looked more closely at the datm community. based on those dissolved silicate concentrations we saw earlier. Uh and her work was really interesting and had some interesting results in um showing impacted datom species. So through the continued use of this sort of single method with minor changes um to the sampling protocol became a lot easier for us to improve and sharpen the focus of each experiment and the standardization of certain aspects also helped us to sort of streamline the comparison process between these different experiments which can become quite difficult as more research is conducted particularly across institutes using different methods. So during these early stages of OA based research, I think these small scale and like lab-based microcosm experiments uh that were completed at you know a heap of different institutes such as Southern Cross and Woods Hole, UC Santa Barbara as well as some initutes in Germany were really important as they allowed us to sort of quickly advance our understanding as they were much shorter in time compared to some of these larger scale ones. Um however, nevertheless, like this is always we're always going to have limitations to such small scale studies um particularly when they're conducted in a single lab or within a single environment. So to combat this, the ocean alkalinity enhancement pelagic impact into comparison project was conceptualized. Um now this is currently being undertaken by researchers across the globe and the primary goal of this project is to sort of efficiently increase our understanding of the impacts of OA but to do so across broad environmental and geographic gradients. Uh so by leveraging the cost effective and pretty well tested method we developed at UTAZ we're sort of hoping to address some of the issues uh that have been identified in the past when in regards to synthesizing research. Um so previous work uh on ocean acidification really illustrated that although it's really great and insightful to have you know a bunch of different approaches being utilized across research institutes it becomes increasingly difficult uh to efficiently sort of synthesize this data. Um, so we're hoping that by employing researchers across the globe to utilize a single method, we can kind of streamline this process and quickly gather a large amount of information which will be informative for future models, field trials and site selection processes. Uh, another really important aspect of this project I think is that it provides an opportunity for early career researchers to get involved um as well as developing research groups. So we're sort of hoping similar to the OE best practice guides that by providing the um equipment as well as a framework for researchers to follow future work will be enabled by these groups at similar or even hopefully greater standards uh and ultimately speeding up global progress. Uh nevertheless as research into OA and MCR as a whole sort of progresses the need and desire to upscale is undeniable. um particularly as these small scale experiments just are not capable of answering some of the questions that we will encounter as OEE is scaled up and this is really well illustrated by the work being done by the likes of planetary technologies investor who are starting to engage with the markets and working at the economics um as well as Loch Ness project at Woods Hole which has done some really important work on community engagement and acceptance you know working with those local communities and the fishing industry the only real downside of these large scale experiments and even some of the more moderately sized ones is the vast amount of time and resources required to undertake them. Um so often only one or two of these trials can be completed each year. They're generally constrained to a single area where they've got all the equipment. Um and a lot of academic uh institutes aren't even capable of completing such trials. Uh so in this case I think these small scale lab based experiments still have quite an important role to play. However, the design becomes increasingly important as we start to transition towards a greater number of field trials. Uh for this reason now and in the nuage, I think these experiments should really shift their focus away from areas which could be better understood by field trials towards areas where these trials start to fall a bit short. Uh one way that this could be done is to reduce a high throughput experiments. Um so these sorts of experiments have been done for other environmental drivers such as light previously. Um and it makes great sense I think to implement them here. Uh so at UTAZ we employed such a methods. So we looked at single cell cultures grown in really small volumes and we were able to grow five species of datom at 60 or 70 unique carbonate chemistry conditions over a six-month period. Um and this enabled us to create these carbonate chemistry fitness landscapes that you see here where you can sort of easily identify the important tipping points at which there might be a significant change in the fitness of a given species and then this may therefore result in a um undesirable ecological impact. Ideally, as we gather more data from similar experiments, um this information would be incorporated into the ecological models and start to inform us of the limits to which a given system could be safely perturbed based on its community composition. Uh this information would also be really beneficial for informing large scale experiments as we could sort of target those specific points in carbonic chemistry that we're interested in rather than repeating large scale experiments until these points are sort of uncovered. And so yeah, I think research in the field of MCR is progressing extremely rapidly as we all know. And as this happens, I think there's several aspects that are becoming increasingly important. Uh one being the efficient release of data and research into the public domain. Uh as we've heard over the previous days, you know, many research groups already have multiple manuscripts and prep. Um and with the pace and progress alongside the growing interest from private companies and governments, it's really critical that this information is shared as quickly as possible so that decisions can be guided by the latest evidence. Uh in this regard, I think the small scale experiments have a quite an important role to play as they often a lot less time consuming and therefore the data can associated with them can be finalized and distributed much faster than some of these large scale uh field trials. However, as I've said, it's really vital that we recognize the strengths and limitations of experiments conducted at different scales. Um, I think future researchers will need to ensure that studies, particularly the ones at smaller scales, continue to expand our knowledge. Um, targeting the weaknesses of these larger, more timeconuming studies. Um, however, at the same time, we should ideally move away from unrealistic experiments that we've done in the past. these experiments that have used excessively high treatment levels or some of the methods that are sort of becoming less likely to be implemented in the future. While obviously there's some subjectivity here, I think maintaining realism will be really essential for ensuring that future research continues to progress efficiently. Uh so by keeping such things in mind when designing experiments we can hopefully continue to accelerate our understanding of MCDR impacts um as we move towards a greater number of safe and effective trials and then prior to the commencement of any potential fullscale deployments. Thank you. >> Thank you Erin. Thanks for sharing this research with us um joining us and staying on time. Excellent. Um so we are going to hold questions to the end. Um there's questions that I think folks will have for for several of you at once. So um we're going to go ahead and move on to Jamie Palter um with the University of Rhode Island. Welcome Jamie. >> Thanks. And I'm assuming that is H. >> Looks great. >> Great. Okay. Um well, thanks for having me and for standing up this committee that's doing really important work. I think um I want to talk about what I call an opportunistic study for ocean alkalinity enhancement. Um, and I'm really going to be focused on the hyper local observing here, not the planetary thinking which probably framed the first two days of your meeting. Um, and here's a picture of us in our our very local system. And I'm trying to advance. Um, which is, um, at the edge or within this coastal lagoon, which colloquially in Rhode Island we call a salt pond. It's about 40 minutes from where I work at the University of Rhode Island. Um, and it's behind this barrier island system. Um and it's flushed tidily through um this breachway here at its eastern end that's you know engineered to be stabilized. It has a residence time of about 4 to 7 days. And what gave us this opportunity to do our work is that um there's a golf course here um that is at the edge of a semi-encclosed little inbamment um that is cut is kind of a bit isolated from the rest of the salt pond because of this sandbar that you can see from from the image. Um so we used um the fact that the golf course would uh wants to put alkalinity like add alkalinity to its soils to maintain you know beautiful greens um as a as a opportunity to look at how that will change the groundwater which makes its way into the salt pond. And this system has no rivers at all delivering fresh water and yet at low tide it can be 2 kilog gram per kilogram fresher. um than at high tide. So, there's a strong um influence of of the groundwater flux. Um okay. So, I'm going to take you on this 10-minuteish journey um over the last two years of fieldwork where we've been in there, and I'll highlight three lessons along the way that I hope will be thoughtprovoking. So, this is kind of my story line. Um we're going to go from the mines and talk about the material that was spread um through its influence on the golf course soils into the groundwater that we measured. Um and then looking at the chemistry of the salt pond. There are lots of things I'm not able to include here because it was a big group. We took for instance um there's a group at the EPA um that also had clams um juvenile clams deployed at two locations and um sampled them to see their growth rates. We had an airc um flux experiment with helium and sulfur hexafllor fluoride led by David Hoe that I won't be able to show in radium. So um I'll show you a a fraction of what we did but I hope um it describes this opportunity that we had to to study it. Okay. So um in 2024 15 tons of crushed limestone were spread on this 9hole golf course. Here's a picture of Copi Becky Robinson talking to the superintendent of the golf course um when he takes one of 80 of these trips with the hopper to spread the limestone on the golf course. The composition of the material is mostly calcium carbonate um at 90% with a smattering of other minerals making up that last 10%. There's nothing else added to it. It's just straight from the um mine and crushed to 1 to 2 millimeter grains. Um, okay. So, that was spread 15 tons in May 2024. We had hoped he would do another 15 tons in May 2025, but he was worried that it was too much and the grass was going to grow too fast. So, he only put down half um last year or less this past spring. So, um, lesson number one from this work is that the public cares a lot less about spreading alkaline substances on land than in the ocean, even when the connectivity between the two is clear. Will spreads this material with no permits. Um, lots of people saw us doing this work in broad daylight, boers, you know, recreational clamming PE, you know, people doing clamming, golfers, and they just thought it was very cool and had no blowback, no permitting requirements, which allowed us to do two years of field work. Um, our premise was that ocean alkalinity enhancement and enhanced rock weathering both ultimately seek to add dissolved inorganic carbon to the ocean, usually via the weathering of rocks. And although we'll hear also about electrochemical techniques um but the social license is a challenge for direct ocean alkalinity enhancement. Our premise was that we would use um the higher social acceptance for landbased spreading to study the influence in the coastal domain. My question is does that is that a promising technique in the future? you'll see possibly an argument against it in some of the results, but um I still think that that's something to consider that both of these techniques um ultimately add carbon to the ocean. Um okay, so going back to our storyline, so we saw the spreading of the limestone um in May of the last two years and then we're going to look at the golf course soils. Luckily, we got um a group from Yale led by Noah Planovski and his great student Aisha Ahmed um to measure the soils. They taught an oceanographer how to poke holes in soil as well. And we can see that it this seemed to work. The um the pH rose by about 02 units um within 3 months of that first treatment. We haven't yet gone back for the second treatment. Um so that was promising. Uh anecdotally, Will from the golf course told me that he needed to use no fertilizer in 2024 because um it had been such a success uh with the limestone application. So it was kind of a nice side effect. Okay. So now we see the limestone appears to have altered the soils. How about the groundwater? So for this we um pounded wells into the golf course in the north, central and south part of the golf course along that little embainment um sixoot wells and go and sample them every 2 weeks and measure total alkalinity dissolved in organic carbon as well as nutrients and radium um although I'm only going to show the total alkalinity here today. So um for the data that we have so far you can see that TA total alinity increased at the north central and southern sites um of the golf course in April 2024. I mean increased at all sites I guess at the northern one it kind of slowly increased and stayed elevated. But this is a real challenge of attribution right that um we only had a very short baseline before the alkalinity was added which is at this blue line. the TA seems to go up just before the limestone was added and stays elevated um except at this southern site where it drops. I'll note that there's just incredible heterogeneity in the groundwater. These like in the absolute value these y-axes are all different um and also in their temporal trends. So that's um it's it's just variable at all time scales. Um but it is notable that at what we called the control site which was in this forested region on the western side of the pond, the total alkalinity crashed. it did not get elevated or stay elevated. Likewise, um the samples we were a able to get from a deep 80 foot well on the golf course which is used for irrigation but available to us when it's not in use for irrigation also didn't have that corresponding increase. So this seemed to be a shallow process in the soils um of the golf course as expected but pretty ambiguous. Okay. Oops. I wanted to show that but I didn't want the sound. Um this is just a brief video of me at the edge of the golf I took at the edge of the golf course kind of walking up this meter inscarment where um you can see the groundwater just seeping into the um salt pond. Um it's just flowing in rivullets. It had been a rainy week and you'll see as the video goes up you'll see the golf course itself. Um and so it's and and we're right by the well there is like the one of the sixoot wells. So, it's natural to expect that the soils changed, the groundwater changed, although the timing is ambiguous. Shouldn't the chemistry of the salt pond as well? So, that's next what we're going to look at. Um, this was an incredible observing effort by amazing students. I just want to call out Shelby and Fiona who um and Brian, the small boats manager, and and there were many others who were out there weekly getting DIC and TA bottle samples and then also measuring them in the lab. um radium and radon also collected. Um and then we had five s moorings with sensors pco2 measured every three hours, temperature, salinity and in 2025 oxygen and pH measured every 15 minutes although the precision on the pH wasn't great and despite this incredible uh measurement effort the changes in the salt pond are really deeply ambiguous. So I'll show a little bit about that. I'm just going to start by showing the salt pond total alkalinity salinity relationship which is highly linear um and gives us an end member that we can look at the fresh end member which should be the groundwater and hypothetically you know in our bestlaid plans that end member would have changed over time. Um, but as you can see, most of our bottle samples are between 25 grams per kilogram salinity and 31 ve at the very salty range and with plenty of variability, which leads to deep uncertainty in the end member and the it kind of hides any variability in that end member. The other take-home of this is the um groundwater total alkalinity is all over the map and a simple average of our samples e either at the golf course or the control site or averaging both do not yield the end member because we don't know they're fluctuating that the best way to do that is through the end member. So it's it's just very hard to see um how changes in the groundwater are affecting the chemistry of the salt pond. Nevertheless, we move forward. We I now here in this plot have subtracted the expected alkalinity from just a constant linear relationship with salinity um and have what I call the excess total alkalinity as a function of time um at all five sites shown in the golf core uh in the in the salt pond. And what you'll see is that there's just tremendous variability including a huge drop in total alkalinity um right around the time the limestone was laid down. Of course, not driven by that, but very likely through calcification that that pulls total alkalinity out of the water as um shellfish are laying down their shells or other other organisms. Um that's the dominant cycle. Um and it coincides with a warming of the waters to about 15° Celsius in that season. It's tantalizing to notice that site three recovers from that drop. And site three is here right next to the golf course. recovers from that drop fastest um and most dramatically and yet these are just a few measurements. So I'd say really hard to attribute that to to the change in the um soils. So lesson number two I would say there is no such thing as a control site especially in the co coastal environment there everything changes everywhere. Um what can we do about that? I mean, I wish I had longer baselining, even more sampling. And then, um, it would be wonderful if we had measured tracers that are exclusively attributable to the perturbation. So, when we hear from Adam, um, and maybe Will who put rotamine in when they uh, have a discharge, then you can trace that. That's not in nature even though alkalinity is. If we had thought to do it, we could have had isotope tracers of the limestone. We didn't do that. So, hindsight is 2020, but it would have been a wonderful way to to look at that. Okay, I'm I'm trying to wrap up and I'm getting there. I just want to show you a little bit of the sensor data where we had these five places. Um, this is mostly raw. It's a little bit quality controlled. The salinity and the PCCO2 at one site. And it's just to show you what the time series look like off the bat. Just variability at every scale. Um, we can zoom in at a few days just to look at what we're up against. The salinity clearly shows the tidal cycle can be as high as 30 and a half at high tide and as low as 28 and a half at low tide. So showing like 10 to you know the swing between 5% ground fresh groundwater and up to 15%. Um and then uh that's the tidal cycle in salinity. The dominant cycle for pCCO2 is the cycle of photosynthesis and respiration. So nighttime is showed in white and daytime in yellow. So at night time the respiration drives the PCCO2 up and during the daytime it pulls it down. But there are other bumps um at these other frequencies that we think um and can show are at the semidal frequency. So if we do some highp pass filtering and a power density distribution we get that in the black PCO2 and in the red salinity both have a huge spike right at that 12.5 hours um two you know two cycles about per day um that's that semidal frequency. So perhaps there's still hope to harness the statistical power of our high resolution data to pull out some of some more of the carbon cycle controls that we want to understand. Um and so this is the third and final lesson and this is where I'll leave you. It's just that if you're working in the coastal ocean the expect variability at every scale and for lots of different reasons. Um, it would have been wonderful to have sensors that measured multiple carbon sister system parameters. The pH and pCCO2 pair, as everyone on this call probably knows, are a really tough pair. They don't give you much independent information. Um, hopefully the total alkalinity sensors under development now will become available. If we had both of those at high resolution accuracy and with low power needs, I think we could have learned even more. And with that, uh, thanks for the time. >> Excellent. Thank you so much, Jamie. Um, so we will take questions for Jamie at the end. Um, so next we have Will Bert with Planetary. Welcome Will. Sorry, here I am. Uh, just trying to set this all up. Okay. Are we seeing the right thing? I take your mute as there. >> Okay. Uh great. Um thanks Kelly and and thanks so much uh to the committee for the opportunity to speak. Um lots of to lots to share here. I'm going to keep an eye on time and inevitably run out. Um because there's a lot to talk about and it's I apologize in advance. This won't be as scientifically detailed as Jamie because I have to go a bit broader. Um so I'm going to talk about planetaries project uh in Nova Scotia which is not planetaries alone um which will be a key highlight of this talk but um I do think it's a real uh bright spot in terms of the way we've been able to advance um this entire field. Okay. So here's the project in one image. So the power plant that generates power for the entire province is located here. and planetary setup shop on the very edge of the power plant. And essentially what's happening is seawater is being pulled into the plant through one of its cooling loops. It's exiting the plant underground and um coming back above ground underneath this wooden structure which is not super easy to see. It it plummet it then plunges back into the harbor in a waterfall which is why it's so foamy and bubbly here. And there's lots of challenges about those that foam and bubbles, but I won't get into that. Um, but when we start out, we essentially add alkalinity right there at the end of the line and then trace it from there. And one really important point is that this is the entire site. And it's really important to think about the scale of the site relative to other carbon removal strategies in terms of its spatial footprint and also in terms of the energy required to run the site. It's the 15 kilwatt hours per ton is a weird unit that I'm sure no one's thought about, but it's a very relevant unit in terms of um the amount of electricity you need to use to um run a project. So this inherently means that that this is a very scalable type of project and that scalability demonstration is what was a big part of what we what we w why we won one of the X prizes for um carbon removal. So here is what here's a couple of different angles of the site again. So this is essentially what it looks like. It looks a little different today because the tanks have all moved around, but it's essentially a mixing tank sitting on top of a spill berm with a sea container in the middle that drives all the pumps and valves and things like that. Um, here it's sitting in the middle of Halifax Harbor, so it's essentially in downtown Halifax. Uh, I should have mentioned at the beginning in Nova Scotia is on the east coast of Canada. Um, it's got this very small footprint, but the scale of the project's quite big. um which you can see in this data here in that in 2024 throughout the fall and particularly into winter we started continuously dosing for the first time for prolonged periods and the the types of rates that you're seeing in this sort of cumulative tons of alkaline minerals is like 35 tons a day. Um so a lot more than the tonnage put on that golf course. Um, but it's, you know, it eventually equates to about 10,000 tons of removals per year. Uh, and I didn't make this super clear, but essentially this is it. It's seawater in a mixing tank. Add your alkaline minerals, mix it up, and pump it back into the outfall. Oh, I should mention this is also year three of the project, which is which is worth noting. Okay, so um, skipping right to the end here. This is demonstrating OA end to end. And I think that's really important because this has got to be more than just science at its core. We need to prove that this industry can become an industry and the only way it does that at least for now is by generating carbon credits. Um so this dosing time series essentially uh results in a generation of about 624 tons of carbon removal. You only get a number like that by doing all the boat surveys, the ocean modeling, the uncertainty propagation, the MRV, and then that has to be verified by a third party. In this case, that party is 350 solutions and placed on an accredited registry, which in this case is isometric. And that is what generates the revenue to keep our lights on so we can continue the trial. Now, it's not profitable at this stage, but the whole point is to bring it to a place where it can be a viable business. And that's ultimately what we're trying to do. Okay, so let's talk about some science. Here is the monitoring uh in a very quick nutshell. Um starting at this image at the bottom. So this shows the sort of narrow part of Halifax Harbor. There's the uh the outfall there at the top. And um the types of assets we have planetary has a wall-mounted mooring about 5 meters away from the dosing location. We've got insitu or flowth through sensors in the pipe um upstream and downstream of where the alkalinity is added and we go out every two weeks on a boat survey to collect your typical water samples. On top of that, you've got Dalhauszy University putting assets like this moing located in this location. It's actually a second moing located now as of as of a month ago upstream of the dosing site higher into the harbor. and um and they obviously are sampling at the same stations as us and additional stations on top of that. Um I should mention that this image was chosen specifically because this was a these are not typical stations that you see on this map. This was a dedicated survey we did last month with Delhauszy specifically driven at looking at dissolution characteristics in situ. So this is the kind of quick reaction, quick uh ability we have to sort of do surveys and and collaborate on on research questions. So quick snapshots of what these data look like. We've got um really clean data showing pH rising above ambient when you're dosing. So the gray lines um indicate times when we're dosing alkalinity. So you've got this very clear pH increase that drops off again when you stop dosing. you can see in the PCCO2 that you are reducing PCCO2 uh during that dosing period and it's maintained at a lower level when you're consistently dosing and then it recovers um after the fact but I won't go into the details there. This is a very important image because it's showing um flow through total suspended solids. So it's this the reason why these um red lines which is downstream of the addition feel like they're capped at a certain level is because we have a permit that says we can only release a total suspended solids of 40 milligrams per liter. So our operations adjusts if necessary to keep us underneath that permit. And it's that kind of you know ability to maintain within existing permits that allow us to to keep moving forward. And it's it adds that level of safety. The boat sampling I will say planetary the way we've approached this is that planetary focuses on the environmental parameters things like seawater metals seawater suspended solids sediment metals things that we can measure regularly and get results back quickly because that allows us to have adaptive management as it allows us to maintain safe safe operations as best we can. Whereas longer term studies of things like phytolanin biomass, environmental DNA, those take months uh for results to trickle in and become sort of uh assessed. So that work is being done uh that deeper level of research is being done by by Delhausy. We are focusing on things we can do quickly um in order to try and maintain a safe operation. So you see sediment metals here, a snapshot of of water column profiles um taken at various sites across the harbor down below. All of that uh all these graphs and everything and the explanation of the work is shown in these reports that end up on the registry every time we release credits. So I recommend you go on the isometric registry and find out this information. Well, I am really hurting for time. I'm going to go much faster. I wasn't planning to speak about ocean models in any detail just to say they are very helpful for more than just quantification also for understanding safe thresholds in the near field and for planning the various surveys that we do. I've got images at the uh the bottom that show sort of our quantification um arrangement but I don't have time to go into the details. This is very important. This is showing how another reason why credit delivery is such a valuable piece to this. You deliver credits. You are forced to put your math, your homework into a public place. You present on that. You you put it out to the world. You get feedback um from whoever wants to give it to you or you openly solicit it like the carbon to seed network did for our first credit delivery. You build new experiments. You build new processes to try and improve the MRV. And then you and then you do improve MRV. end up with a lower carbon intensity of your of your um project. That's that's not an MRV improvement. That's a performance improvement. We have a different and better approach to modeling. That's an MRV improvement. And then you deliver more credits and the cycle continues. By no means do we think this is perfect, but every time we go through this cycle, we get better and better. Okay, so wrapping up a bit, the success of this trial is is really down to collaboration and transparency across really a bunch of groups, but the three most important are scientific groups. So Delhausy, I meet with Dhazi every week and that's detailed logistical planning, sharing results, sharing data. We also have external collaborations from places all over the world. Our regulatory and government interactions are very important. Lots of different agencies. We have to proactively reach out. We don't often get responses back from these agencies. But it's very important to recognize that this project integrates into existing regulations very well. Uh the provincial government regulates outfall discharges. So that's who we work with. The federal government regulates or enforces the fisheries act. So they come to our site and collect samples whenever they want to make sure we are not being delterious to fish. That is how they enforce the fisheries act and we comply and have a framework around existing environmental quality standards and those are the standards we use to examine environmental thresholds. Okay. And and um this is not my area of the business. Thank goodness uh our VP of community Diana now runs this. But our the most striking thing about this project in the last year has been how it is far beyond a scientific field trial. So now we are moving through her framework of engagement which includes engagement but it it goes to higher levels and the level we are at basically now is this level of collaboration. We are no longer just informing uh community of our work. We have u multiple indigenous uh organizations who are actively collaborating with the project. Um we have uh organizations across the provincial local governments uh city council. We had an event here just last week um with the little snapshot here which really brought that home. The people who were there spanned many scientists as well but really expansive in terms of um the excitement and the momentum that people feel across the city and the province about this work and the and the kind of um uh value it can generate. So, some quotes here at the bottom from uh member 2 nation and from city councilors, but just to say it it really struck home last week uh particularly how much this has expanded beyond science. The last couple things I'll say is that moving to a continuous dosing phase where we are now at these sort of 10 kiloton level, this is where we start to re realistically and robustly assess biological impacts, right? That's that's when you're going to really learn about these things. It's going to be very challenging to do that in a oneweek ore or a one-month experiment, but at this scale where we get measurable impacts um and it's prolonged that there's a lot of opportunity there. And uh this quote by Phil Duna I think is very powerful. Creating the conditions for learning uh safely transparency at a scale that begins to matter. And that means bringing all these different organizations I said before. Bringing them in. Come to Halifax. Come learn about this here. And um happy to answer questions. Sorry for going over time. >> No problem. Thank you so much, Will. That was a great overview. And I know for everyone it's a lot to squeeze into 10 minutes. So thank you. Uh we know we can always dig in deeper afterwards and um you know we will. So um moving right along we have two more um speakers today. We've got Mallalerie Ringham with EB Cardon Carbon next. Welcome Mallerie. >> Great. And you can see my slide. >> Yes. >> Perfect. I'm glad to be here. My name is Mallerie. I'm a chemical oceanographer working for Abcarbon. And similar to Well's talk, I'm going to be kind of giving a broad picture of a project that we've been developing. So I won't be getting too terribly far into data here. Um lot is going to go into this talk. So my email is here and then repeat it at the end as well. Now can I advance my slides is the question. Yes, there we go. So EB's approach to MCDR is electrochemical ocean alkalinity enhancement. So what we're doing is we're processing seawater or brine. We separate salt into acid and base streams and we remove the acid stream. The base stream is recombined with seawater and released through a coastal outfall and that's the alkaline signal that we're working with. There are many similarities between this process and other OEE approaches. But often you'll see in the literature now um that there's a distinction between electrochemical OA and mineral OA. And that's because the base stream that we produce, it's effectively a form of sodium hydroxide that's been used in many laboratory studies and now a handful of field trials. But by stripping acid from seawater, we're not adding something new to seawater like sourcing alkaline minerals and industrial waste and so on and adding that to seawater. We're really producing the alkalinity from what we're starting with. Um the other difference between this and mineral streams is that our alkalinity is aquous. So we don't have to worry about that dissolution step when you're releasing alkalinity into the coastal ocean. And that can do some simplifications when you're talking about modeling where that alkalinity goes. We've been really slow and methodical in our development. Our approach to MCDR is spun out of more than a decade of research by our late chief scientist Matt Isman who worked on direct ocean capture as part of Google X's project Fogghorn before turning to alkalinity enhancement. And much of our work that I'll talk about here is based in private public partnerships that have really allowed us to test and scale our work before we've moved into the commercial development. So these are just a couple photos of some of EB's technological development work. On the left is a benchtop test of a variety of different types of commercially available electrochemical membranes. These are of the type that are already commercially available and used in industries like dissolination. On the right is a series of 200 membranes stacked together. This is in our manufacturing headquarters in South San Francisco. And if you combine those stacks into modules, you end up with shipping containers of electrochemical work. And you can deploy that easily in the field enable to enable you to generate alkalinity on site. In 2023, we deployed a small abcarbon system at PNNL, the Pacific Northwest National Laboratory Campus in Swim, Washington. We ran that system through its paces to generate acid and base from real seawater. And we use that acid and base stream in a variety of experiments, including two case studies where we discharged alkalinity through the existing wastewater treatment facility at PNNL. The write up of those experiments is in the final phase of publication and it should be available imminently for anyone interested in taking a look. These snapshots include part of the team in front of the installed upcarbon system. There's a species impact study in the middle and then on the far right is a photograph of a cage of carbonate sensors, PCCO2, pH and water quality sensors dropped directly onto the outfall at PNOW. Much of this work again is enabled by federal academic private collaborations. In this case, the EOA project is one that was hosted between Upcarbon, PNL, Noah PMEL and the University of Washington. I'm not going to hover on this slide to save time, but I wanted to give a sense of the range of research that's coming out of this work, both current and upcoming. And if anyone wants access to these papers, feel free to shoot me a message. Okay, so the small white circle on the right shows where our demonstration is. It's at the mouth of Squim Bay. Working in this area in Washington state has been hugely valuable for us because as we got to know the area from working at Squim, we were able to talk with a wide variety of groups and that helped us network and land our next project site which is about 30 miles west in Port Angeles, Washington. And I want to point out that Washington state is a really standout area to do MCDR work. We're surrounded by oceanographic experts in both the US and Canada. There's a political will to tackle climate problems with a particular focus on ocean acidification. And that means that many community climate technology. So we can engage with a lot of people that we might not be able to reach in other locations. The renewable energy grid is valuable for CDR development in this area. The coastal ocean is really well understood. There's extensive monitoring here and extensive modeling. There's two regional ocean models that overlap in the sish sea that are both capable of handling carbonate chemistry. And then Washington state is one of the most rigorous locations to work in terms of water quality permitting. And this is really a case for us to stress test our path to permitting these projects. Okay, so this is what our research site, Project Makoma, looks like. If you hear noises in my background, it's because I'm on site and there's a lot happening here today. Um, there's a dark line in the background of this photo. That is the natural EDS hook that makes up the western edge of Port Angeles Harbor. There's a Coast Guard station on the eastern end of that hook. And then you can see this big structure that stands out over the water. This is a pre-existing industrial pier that we've leveraged so that we can walk effectively across our entire signal of what we're putting into the water. Okay, so there's multiple components in this project. Out in the water at the west end of this pier, there's a little red barge. That barge is our infrastructure for our seawater intake and our alkaline diffuser infrastructure. Then on land, you can see that there's a series of containers and holding tanks. The equipment on the far left is associated with an on-site disselination facility. So in the future, we intend to integrate this technology with existing coastal infrastructure in order to scale. And we can do that quite effectively by tapping into someone else's efforts to pump, to filter, to concentrate seawater. But because this is a standalone research pilot, we do it all ourselves. The second cluster of containers in the middle, that's our electrochemical system. And then on the far right, there's an office and some equipment for processing acid on site. So last fall, EPC carbon secured a first-of-akind permit for MCDR under the Clean Water Act. This is a national pollution discharge elimination system permit and that lays out the conditions for a mixing zone where we are allowed to dilute alkalinity from that bargebased outfall system. It sets up a chronic mixing zone that's 207 ft across and effectively by the edge of it, our alkalinity has to be sufficiently diluted so that seawater samples and sensor measurements reflect excellent water quality standards. Under routine operating conditions, we can release alkalinity with a pH up to 9.8. And I want to point out that this is not the only permit for this project. There's many, many, many permits at a variety of levels that include shoreline protections, fish and wildlife, army corps, etc. We were in contact with our regulators which are the Washington State Department of Ecology long before we submitted our permit application. So we began talking with the port, local tribes, coast guard, variety of other folks a year before submitting our permit application. The permit process itself took about nine months and that includes public comment periods. All of that permit documentation including the comments themselves from the public are publicly available. So when we release alkalinity, we lose sight of it very quickly in the mixing zone. And that's the nature of working in an open system. We can't directly measure the carbon dioxide removal that we're leveraging the ocean to do. So quantification of carbon removal necessarily becomes a modeling exercise and that's informed by the alkalinity dosing records at the site on land and near field measurements within our mixing zone. One of the first steps in modeling CDR is to model the dilution of the alkalinity into the ocean. This is certainly eased by having an alkaline product that is aquous going into the ocean. So early in project development, we contracted an engineering firm to conduct really routine standard dilution modeling. This uses the EPA supported visual plumes which has recently been replaced by plumes 2.0 with OI software for chemistry. This is part of the design process, part of the permit application and that's evaluated by the regulators to determine an appropriate mixing zone. The dilution model was validated with a die tracer study. You may be able to see in this photo there is a slight red tinge in the water behind that boat. That's a rotating die. So beyond the dilution model, we are able to use the University of Washington live ocean ROM system to simulate alkaline release. There's a variety of steps involved in this. I am not the primary modeler on this project by any means, but in general, what we're doing is we're running simulations with and without alkalinity and comparing them over time. That effectively calculates the carbonate parameters and how they shift over time in space. And then the difference in air gas exchange between those simulations is the amount of carbon dioxide removal that occurs over time. And then from that gross CDR, we subtract off project emissions and efficiencies and so on. And that gets to the net project CDR which is the thing that is credited at the end of the day. If you're curious about this work um reach out but also look for us at AGU ocean sciences meeting this year. We will have uh presentations on this. Okay. So on the measurement side I always think it's important that we talk about measurements in the context of their purpose and that can really range from fulfilling regulatory requirements, crediting requirements, sanity checking or validating models. Our permit requires the figure on the top which is monitoring seawater temperature, dissolved oxygen, turbidity and pH at multiple locations. This includes within our outfall system and in the ocean which is near, at and beyond the edge of our mixing zone boundary. On top of that, we use higher precision oceanographic sensors to model additional parameters that includes chlorella, pH, pCCO2 at the edge of the mixing zone. We work under the same um protocol that will uh mentioned earlier, the isometric OA for coastal outfalls. We actually started monitoring at this site around the same time we submitted our permit application, so well in advance of any alkaline work. Um and so that's been able to generate a really robust baseline for this site. There's sampling on top of this work. Happy to talk about that as well. There are many studies that we wanted or that members of the local community wanted to see around project makoma as we talked through development. So through that project design period, we co-designed an ecological safety methodology with our regulators, local tribes, and an environmental consultant that became incorporated into our permit documents and requirements. So this methodology describes biological monitoring as well as well as adaptive management procedures at site. It also describes some additional voluntary scientific studies. So on the left there's a quick screen grab from a visual survey of the project area. What we really wanted to understand was the types of marine habitats that we're working near. And then on the right there's a sediment profile imaging survey that includes infal succession redux benthic habitat so on. Last winter a local tribe donated juvenile coo salmon from their hatchery. This was for an XC2 laboratory study and we worked with the tribe and a local toxicology lab to design a study that exposes the salmon to conditions as if they were swimming by the outfall diffuser when alkalinity is being released. Um, I'm about to hit submit on a description of the study for peer review, but the basic lab report is already in the public domain. And then another small study at this site, a local shellfish hatchery donated Mediterranean muscles. These grow in bags from our barge, edge of the mixing zone, east end of the pier in ambient conditions. and we monitor those for survival and growth over time. So, these are just some examples of some of the additional work that's going on. And uh that puts me out of time, so here's my email. Happy to answer questions. >> Thanks so much, Mallerie. Um and yeah, I really appreciate all of you for abiding by the the time limit um because we really really want to get to discussion. Um so, we have one more um one more speaker. He's actually one of our committee members as well. Um, Adam Tbas, he's uh recently back from the Loch Ness field trial. Um, he's with the Woodsole Oceanographic Institute. Um, thank you, Adam. The floor is yours. >> Thanks, Kelly. Um, and great to see uh everything here. Hold on, let me see. Should I flip my slides here? Are you seeing >> view or Yeah, the There we go. should be able to turn that off. Okay, excellent. Uh thanks uh Kelly and the committee for um giving me this opportunity to give an update on Loch Ness and really great to see um everyone else's um foray into the field and music etc as well. Um so this project the Loch Ness project um Loch Ness stands for blocking ocean carbon in the northeast shelf and slope. Um we are a team of 20 who scientists from all five departments here and include colleagues from Rutgers University uh glider manufacturer MRB systems um environmental defense fund and UC Santa Barbara um and there are funding sources uh below. Um I always like to give a positionality statement here in the front of our talks. We are an interdisciplinary team of scientists, engineers and communicators. Um, we're committed to a rigorous, transparent, uh, scientific evaluation of OEE, um, and answering key questions about the effectiveness and the potential environmental impacts of this approach. Um, we're not a company selling CO2 credits or participating in the carbon market. Um, and we don't see this project as a template for deploying alkalinity uh, enhancement at scale. I'm going to go through the next set of slides fairly quickly because um, I've talked about them a lot. Um but I just want to give some sense of what went into in terms of the science um actually giving us the confidence of of doing this field experiment that that happened in August. Um we did a whole series of baseline monitoring um everything from the chemistry um the biology and the physics. Again, like um Washington, this region of um the US coast is very heavily monitored um from everything uh from the physics all the way up through the presence of marine mammals and endangered species. And all of that data, that publicly available data was really really critical um in terms of us being able to understand um where this site was, putting it in context, etc. Um we have a whole suite of biological impact experiments that we've done uh in the lab on ships of opportunity um etc. So that includes everything from phytolankton up through um copapods. Um we did do a series of engineering tests as well to to look at the safety and efficacy of the dispersal of our alkalinity source which um like Mallalerie is sodium hydroxide. Um and this went into our understanding of how to actually practically do the dispersal um in a safe and effective manner. Um and matched that up to shipweight dilution models and other other dilution um uh models that are out there. We also conducted a rotamine tracer test. This happened back in 2023. Here's an image of our plume and on the right is um the track the ship track of us tracking that plume for about 36 hours. All this to say is that um we um put a lot of work into making sure that we had the technologies and the methodologies to track and measure um uh this intervention through time uh in the open ocean on a ship. Um and and indeed we can and and we have confidence from this experiment that that we would be able to see um the alkalinity enhancement and potentially even the carbon dioxide removal as well. We've done a lot of public outreach and engagement um with a whole different set of communities um and agencies and interest groups and um etc. Um we're about to submit a paper on our sort of engagement process um along with our EDF colleagues. So keep an eye out for that. Um the experiment itself occurred this August um in the Gulf of Maine, the Wilkinson Basin area of the Gulf of Maine um approximately at this dot location that's actually two scale the size of the um uh the patch. Uh it involved a dispersal of about 65,000 L um of 50 weight% sodium hydroxide solution. that corresponds to roughly 50 tons of uh liquid alkalinity um and about 200 lers of 20% rotamine water tracer dye as well to kind of label that um that alkalinity and then track it around. Um since then this this um dashed line here indicates the survey area where we expected from our models the patch might move um in that area before fully dispersing. not that it would spread out to that entire circle size. It would sort of get diluted and then um and then uh uh potentially move with currents and tides within this circle. So that was our kind of survey area. Um we did leave for the port of Quincy um uh with the dispersal vessel. Uh this Portsmith site was a was a backup site for us. Our EPA permitting was through the marine protection research and sanctuaries act as described by Will Burns yesterday. Um we went through two rounds of public comment with uh a sort of set of um engagement, feedback and uh resubmission of a permit application um uh ahead of that second public comment period. So we did do a series of sort of um revising our project plan uh responding to concerns and questions and submitting a new project design um for public comment. Um that was that second comment was in 2025. Um and the final permit was issued late April um uh this year. And uh as with others, you know, these permitting discussions uh started well before we submitted a permit application. Um uh and so this is a very long process with with lots of consultation with other agencies and and groups as well. Um EPA project page is uh is here on the QR code if you're interested. Um we tried to measure as many things as humanly possible um on a small 90 foot research vessel. Um and I'm happy to say that we we did u pretty much everything that you can see here. So um rosette cast sampling the vertical structure of the water column plankton toes um uh uh drifting assets. Uh I think uh during the monitoring phase we had 13 independent assets um taking measurements uh during this uh experiment. We had some drone drone imagery um and we also have some satellite imagery as well um of what happened. Uh and the ship was basically constantly transiting through the patch this entire time. Um we had three vessels on site during the dispersal. Um the Mahoney was the dispersal ship. um six crew, four HOIE engineers, three alkalinity handlers um from our our contractors who supplied the alkalinity, four observers, including observers from the EPA, protected species observers, and the we we invited a fishing industry observer as well along on board. The Connecticut, the research vessel had seven uh ships crew and 10 science crew. The Tyogga had two crew, four HOIE science members, um, three media and two observers from Massachusetts Department of Marine Fisheries and the Noah Northeast Fishery Science Center. Um, we also had a shoride team operating the autonomous underwater vehicles, including five glider operators and three operators at the Longrange AUV. Um, so those were our um, autonomous assets in the water, including um, some Lrangeian drifters. Uh, so this is a shot from the dispersal itself. Um from the back you know you're looking over the stern of the Mahoney um during the dispersal you can see that what I'm calling the yellow brick road here um and the Connecticut following in the path um we had real time monitoring of rotamine pH PCCO2 total alkalinity Fe over FM which is a measurement of photosynthetic health and uh oxygen concentration uh uh during the dispersal. This both helped us satisfy permit conditions around uh maintaining pH thresholds but also gives us a really detailed understanding of how the biological community at the phytolanton level was responding to this this elevated pH. Um the Mahoney was also uh uh continuously monitoring pumping rate volume speed and the protected species observers were active this entire time as well. I'm happy to say that there were no protected species observed um during during the dispersal uh itself. um actually during the whole monitoring period. Um okay, so really cool satellites, we caught the patch. So you can see it here um in the satellite image that we took the day after the um dispersal was completed. You can see it here um in the long axis. This is about 4 kilometers across. Um so quite big and it it only grew bigger over time. Um just to give you some sense of how we're approaching the data model under comparison. This is a ROM's uh ocean model simulation of what the rotoine concentration would do um in days since release. Um the detection limit about 0.1 ppb. We were expecting to lose the patch around day four. And sure enough um we actually had to return to port due to weather on day four and the AEVs lost the um the patch signal on on day five. So again, pretty good um agreement between the model and and what we actually saw out there. And of course, this is a hindcast, so we're we're looking to um run a 2025 simulation in August to really get get the best um data model under comparison. Um just to give you a sense of what we were able to do with the gliders, we were we were actually unconvinced the gliders would be able to see anything at all. Um but here is a day section of glider profiles um on the 15th of August. Um in general we we collected over 2,000 individual profiles um over these four days from the glider. So just unprecedented um resolution of what was happening in the upper ocean during this time. The top panel is density. Um and again we picked summertime because you have this really um buoyant layer of water that we thought would trap the alkalinity at the surface. The middle panel is rotamine. So again when the gliders were actually profiling in the patch you can see an excellent agreement with this low density water mass sitting right at top every time the gliders were passing through the patch. When we lose the roto here that's just because the gliders were doing a profile outside the patch rather than inside the patch. Um and again those gliders also had pH and oxygen and so we have a really good sense of how the alkalinity was interacting with um you know the biological aspects of the system at the same time. Um we have a lot of other data plankton toes conducted daily um all sorts of CTD data many many stories many things to come but I just wanted to give some sort of highle highlights of of what we saw and and what you can expect from us uh moving forward. Of course, the big the big question is how much CO2 did we actually measure getting pulled out? Um and uh keep an eye on that. Um especially around ocean science this time. Um here's a link to our website. Thank you. And I'll I'll pass it back to uh to Kelly. >> We look forward to that, Adam. Um thank you so much. Um so, uh we have again plenty of time for questions. I know everyone will have several. Um, you can use the hand raise and we'll call on you and the order that your hands are raised. Um, Gabby. >> Hi everybody. Um, hope you can hear me all right since I'm in transit here. My question is for Adam. Um on this Block Nest project, you mentioned that this method that you tested adding sodium hydroxide wasn't necessarily meant to to move to scale. So I was wondering if you could comment on that a little bit more. What are the kind of high level takeaways um in your own words that can be applied to other ocean enhancement methods that can exist at scale? Thanks. >> Yeah, thanks Gabby. So, so our our goal for this project was to really demonstrate um the feasibility of the mechanism of carbon dioxide removal that ocean alkalinity enhancement uh is based on and that is the production of alkalinity at the surface and the ability of that alkalinity to take up carbon from the atmosphere. And so the reason that we picked sodium hydroxide as Mallerie said is it's a liquid form. It's missable in seawater and readily dissolves without this mineral step of alkalinity production that's actually quite complicated to model and to measure in the field. Um and uh that's a really critical piece that I I think we need to to understand a lot more about. Um but so so the project was really focused on this mechanism of carbon dioxide removal and um we hope that we have the data to kind of really demonstrate this mechanism in action um with this experiment and I hope that that can lay a scientific foundation for um deciding making decisions about the effectiveness of this approach but it you know the way that we did this experiment and um the alkalinity source etc you know isn't necessarily what scalable alkalinity enhancement could or should look like. >> Thank you, Adam. Uh, Lisa, >> hi. Uh, I want to thank everybody for really clear and really informative talks. I have a a a set of questions. I'll just throw them all out there. And the first one's for Erin. I really liked to see that uh last chart you showed on the different thresholds for the different phytolanton species and I wondered whether anything is known about the con I don't know if all those species co- occur together but is there anything known about the consequences of changing um of having different species dominate for for further up the food chain. I'm just gonna ask all my questions to right right now. Um so that's that was for Erin and then um for let's see I'll just one second. Um the next one I think was for Will and um I wanted to know I I thought the continuous dosing and sensing is really really interesting and I wanted to know whether um from that and the continuous sensing. Can you un better understand the influence of tides or storms or climatic events on the um subsequent effectiveness of the alkalinity and where it goes and and its draw down ability ability to draw down carbon dioxide like are you going to get a lot of um information about temporal variability? I would assume yes, but and then the the last question um is is for Mallalerie and you mentioned uh that there's juvenile coho experiments and muscle response experiments and I wondered whether you were doing dungeonous crab experiments but do you have um any inkling of any results from those and um is there any response? So those are my questions. Okay, thank you, Lisa. Um, why don't we go in reverse order? Mallerie, do you want to start since that one's freshest? >> Sure. Um, so I'll start with the juvenile coho. So, that was a really interesting experiment. Um, the way that we set it up, we really wanted to understand not the traditional toxicology where you're looking for concentration that impacts species, but what happens in the field. So, when I release alkalinity, if a fish is swimming by our our field site, what does that look like? So what we did was we took the mixing zone analyses and we took the predicted pH at 10 feet from the alkaline diffuser and we mimicked that in the lab. We released alkalinity that we produced into um a test chamber and we did that at varying time stamps. So between 30 seconds and 5 minutes of exposure to that dilution factor of alkalinity. And we compared physical and um behavioral responses between the fish that were tested in that way and the controls. And then the alkaline exposure actually continued past that period because you're flushing in raw sea water as if the fish is swimming away, right? Um, all of that can be summarized by saying that these these pilot trials, you're diffusing alkalinity very quickly, but it's still a small trial. And within the acute mixing zone at that distance, we're down to a pH of about eight, which is fairly normal for juvenile coho salmon that swim up and down in the rivers, there's absolutely no difference that we've been able to assess in biological, uh, physiological, behavioral responses. Um, we will be repeating that test at a higher alkalinity release. Um, and so that will be in the the public domain soon. Um, and I'm happy to talk about that more. The shellfish one is also interesting. They are in seu, so they're in the field site. They've been growing out there for most of the summer and they've had periodic releases of alkalinity across the shells. So far, no change between control and experiment sites at that acute mixing zone. So, right near the diffuser. We have not done dungeonous crab experiments although there are others in the area who have been working on that. At PNNL we did other local um eelgrass epipana sea hairs and isopods. That paper is available. It's Jones at all 2024. And in that case depending on the um the length of exposure. There are some differences in in individual species response that get really difficult to tease apart when you're working with very fragile species like sea hair. So, um, happy to point people towards those. And yeah, I'll stop there. >> Thank you, Mallerie. Um, Will, do you want to talk about um understanding the influence of tides and storms um on the effectiveness of draw down? >> Yeah, I guess there's I was thinking there's kind of two ways to think about it in terms of the draw down. Yeah, I mean of course these scales really matter, but I think seasonal um seasonal scales are going to become the most important when it comes to the overall draw down. And the models, you know, the models already know that the the benefit of these continuous dosing studies is that we can start to see whether those models are are, you know, in line with the kind of things we can measure in the near field. But um more importantly I think uh for what you said is what the tides do to the near field because um that is that's that's where things like tides are going to be much more important. So for example we have um at the low tide uh you've got um less water to dilute into uh and you've got slower moving water of course at slack tide. So we do see a really like a a we we see impacts to the operation based on the tidal stage um in that you have more suspended solids in the water column at certain stages of the tide. So um those sort of tidal level variability is more impactful to uh sort of permit compliance and and super nearfield processes. Um I don't think things like tides are going to play a big role in your overall sequestration. Um, but these are the kinds of things we'll learn as we go. >> Thank you. Will Erin, uh, do you want to comment on consequences on different marine species? >> Yes. Um, so yes, to answer your question, all those species do occur in the same location. They're all all of that sort of isolating work was done at the same site that all of our microcosm experiments were done. So they're all species that we would commonly find in the microcosms. Um in terms of the interactions and then the ongoing ecological impacts is a little bit more complex particularly because those high throughput experiments I did we were looking at alkaline ranges of sort of 2,00 to 3,600 whereas our experiments were more 500 microL increases. Um so we have seen some impacts. Um in that first paper we sort of had the decrease in dissolved silicut and then in the second paper that came out by uh ka we had the shifts in the community composition and sort of starts to link together that these shifts within the datomic community can impact the production of biogenic silica and dissolve silicate but um again in terms of like the plots that I showed in my presentation they're much higher alkaline levels much lower the levels and things like that. So, it's not something that we're not going to see such dramatic decreases in um the growth rates is what I was showing there. Um so, yeah, I hope that answers the question. >> Thank you, Erin. >> Can I just go ahead follow up real fast? Um, but but do you know like are those different species preferentially eaten by different components of the food web or are there any known consequences of having one dominate over the other? um for >> in terms of in terms of the food wear per se, I'm not 100% sure, but some of the things that Kais touches on in her paper is that one of the species that seems to be predominantly impacted is Sudichia, which um can also be can commonly have toxins which can cause shellfish poisoning. And then we've also seen some impacts with ketoseros as well, which is relatively prolific, but can have some implications for fisheries as well. Um but in terms of sort of like um going from the phytolanin to zup plankton up we haven't specifically looked into that so I can't really comment on it at this stage. >> Thank you. >> Thank you. Um Jessica >> so my question for the panel today is about how we think about control sites. Uh so across the different experiments we saw profile today we saw a variety of different control techniques mentioned. Um for example Jamie chose a distant control site and other experiments that we saw chose controls that were I you know very nearby essentially just outside their plume in order to make measurements. So Jamie I'll I'll sort of start with you and then direct a broader question to the rest of the panel. So you showed on one of your slides the quote there is no such thing as a control site. Uh and so my question for you is do you think that was an issue of scale? Like you know is the signal to noise ratio in the area you were working simply too high uh to use or envision a control site in the way that you did or do you think that distant control sites are just a broad fiction that shouldn't be applied sort of in the MCDR context? And then um for the rest of the panel as well, you know, making measurements both inside and outside your plume, should we consider that both a an experimental variable and a control? Like is that a control site or should there be another sort of version or or terminology that when we say control site, we mean something very specific? So Jamie, I'll throw it to you first and then welcome comments from the rest of the panel. >> Yeah, thanks for that. Um, I wanted to like be provocative a little bit. Um, in in the system that we're in, for sure, the spatial variability, it's just everything's so patchy. It's almost like even we're in this little tiny boat. Even if you grab your sample from the wrong side of the boat relative to where the sensor is, you can find um chemical differences and temperature and salinity and um so what can be done? Um I think it's brilliant to have a patch of rotamine and you're in the patch and out of the patch then you just know because you've done this uh intentional deployment. The question is that's a kind of one-ofa-kind experiment. So um where do we go from there? Uh I I am really curious actually. Um I think you know Will has this brilliant thing where it's on or off and he can see the system reset to a background. Um, so I think that's a really great analog for control. Um, but I So with that, I'll turn that over to to others to I'll punt a little bit and and see what they what they say. >> Looks like Mallalerie wants to chime in. >> Yeah, I'll jump in there. I'm I'm not a fan of the term control site for anything in the coastal environment. Um, it gets really complicated to envision a control site. Like if we look at our harbor, is there another harbor nearby that has similar biogeeochemistry? Probably not. Um, we're fortunate that we can walk across most of our mixing zone. So, we sense in the plume, out of the plume, further outside of the mixing zone where we don't expect or ever see any alkalinity impacts. And that's the closest thing I think we're going to get that. And like Jamie suggested, the on and the off. You know, if if we are really recording all of these measurements at high resolution as much as we can with sensors, that's great. That gives us a sense of what's happening from day to day. Um, something I do want to mention is I've often seen or heard folks talking about the concept of the baseline and how we use that. So, if we're monitoring conditions in advance of any alkalinity additions and then we're doing alkalinity additions, it's hard to compare across those time periods. So, at least if you're dosing alkalinity one day and not the other, you know, you're you're far more similar in terms of what's in the area, what's swimming through, what the biological context is like. So, I think it becomes a really complicated situation. I don't think the term control really means much to us and I'd also argue I don't think the term baseline means much to us either. >> Yeah, thank you Mallerie Will. >> Yeah. Um completely agree. I you didn't I don't think I said the word control site and that would have been intentional. Uh I do think this idea of a temporal control is is more valuable. Um, but it's important to note that it's valuable at this moment for for general R&D and for sort of in plume out of plume. These are really important for things like compliance. Um, and me and Mallerie I don't want to put words in Mallalerie's mouth. We have to think about that stuff a lot. Um, so that is that is where your your idea of of measuring here and measuring there and comparing them is really important. It's a totally different beast when you're thinking about the level of detail that Jamie and Adam are trying to delve into, which is like the actual measured quantification, which of course in these coastal environments is really, really, really challenging. And so I do think it's worth noting that the one way you can do that is with an ocean model where you've got a two scenarios that are identical except one has alkalinity and one does not. So say what you will about ocean models, but they're very powerful because of that capability of having keeping all the other elements the same except for that one very important element of adding alkalinity. So I think that's it's not really a great solution per se, but I think that that that that's there for a reason. >> Thanks Will Adam. >> Yeah. Um, thanks uh, Will for for bringing up models because I was just going to say, right, I think the to just to add on another term here, right, the counterfactual is the way that the modeling community talks about quoteunquote control, right? And so I think all of these terms are imperfect for what we want to do. food counterfactual also has this sort of climate sort of implication right behind it um about you know what would have happened without this intervention um which then gets into this concept of additionality. I think this is where the rubber meets the road in terms of like thinking about controls or baselines or counterfactuals or whatever. Um but you know from our perspective being able to to make the measurements to ensure that the the models are you know at least somewhat telling you the right answer I think is really really critical. Um and that is not only at the sort of large scale um uh of say a global model or the kind of stuff that you know you're looking at like you know global regional differences in air seed gas exchange but even at these small scales like when you take these measurements when you do in patch out of patch in plume out of plume switches on switches off like can you um come up with a budget or come up with a um numbers that can directly inform model performance, right? Or how the model is able to reproduce that system in silicone. And I think that's a really important research um area for for us all to be thinking about um right now. >> Follow-up question. Um a number of you have mentioned on and off um as your potential of seeing these impacts. Uh but a number of you have also mentioned that you're trying to move away from pulse releases. There seems to be some tension there. >> I mean, I wouldn't call it tension in that, you know, no engineered no no operation in history operates 24/7 365. So, there will always be downtime. Um, and we've we just recently we sampled during that downtime specifically to grab some sort of off samples. So, continuous. Okay. Not quite continuous, but yeah, I mean, you're going to want to be running fairly often to to be economically viable. >> How frequent are your downtime periods? Will >> How many follow-up questions do you get, Jess? Uh, I I mean, it it really depends. Um, sometimes they're hours, sometimes they're days. Oh, in fact, there was one that was three weeks long recently, so it varies. >> Point being, are you taking the weekends off? Are you not running at night? Is this like a daily thing? Like how frequent are your downtime periods? Not necessarily. How long are they? >> They're sporadic, but there's definitely hours every week where we are not operating, but it's only hours at most. >> I'll quit with the follow questions because I want to be respectful of Kelly. >> Thank you. Uh we can get back to Jessica if you put your name at the bottom there. Um so let's see Will Barrelson next. >> Yeah. Hey, thanks all and excellent talks all and I'm uh specifically interested in following up with Adam on the the AUV asset flying around and doing this continuous survey is incredibly useful especially in light of the comparison to what you get with just spot sampling which is you know you're only able to drive a ship so far and put in the uh CTD every so often. So I assume you're going to you know reveal in the literature how right and wrong you can be depending on your data density that would be a very very useful part of what you could contribute and this is quite a question but then the roamine the patchiness which we've heard and Jaime's you know emphasized how variable these environments are always going to be The again another thing I'd love to see is the rotamine versus pH plot and un start to get a grip on the kinetics if you think it's a single uh phenomena or what's really happening is there's subduction and there's different periods of time when that water is in contact with the atmosphere. So I'm asking for just I'm really eager to see more more depth on what you've been doing. Uh yeah, give us uh I don't know, six months and a year and we'll get back to you. But um absolutely. No, I think and and we were we were just so thrilled with with how successful the gliders were. Um and you know, we were able to do I think 30 something CTD casts over four days on the Connecticut, which is like a CTddD every, you know, 3 to four hours, something like that, which sounds like a lot for a ship. Um but compared to 2,000 profiles with gliders, it's it's just unprecedented. um data density. So we're really excited to dig into that. I think you know we have this paper in biogciences from the um that is a preprint um on the rotamine only trial and we kind of dig into some of this just background variability and what that means for attributing a rotamine signal to CDR and and the the magnitude of CDR signals we actually think we would be able to see with an intervention like this um over say 24 to to 96 hours. Um, but we're absolutely I mean that's the that's the sort of analytical framework that we've set up and we're really really excited to apply that to an actual alkalinity enhancement experiment now. So, um, yeah, stay tuned for sure. >> Yeah, thank you. Uh, Libby, >> I'm gonna I'm gonna do the Lisa approach where I'm gonna call out the name and then ask a question and let Kelly figure it out. So, um I have uh three questions for three different people. Um one for Jamie. Um I'm curious if you have any and maybe you said maybe you already have answered this in your talk, but I I didn't hear it. I don't think um you were showing increases in total alkalinity, but you weren't able to correlate that with what when you were putting the stuff down on the golf course. um do you have any theories on what that cycling was and would that be helpful for you know future work especially coastal work um like this. So that's kind of maybe an easy question for you um or not. Um Mallerie question. Um uh have you thought about um looking at and maybe it's I'm not sure it's re relevant but I think it might be um what parts of the plankton community might be entrained as you're sucking that water in and could it be could it be changing the composition of the ecosystem on the other side. So you have the obviously the effects of whatever is coming out the other side, but you're also changing the water. So that's question for you. And then will um a question about engagement um and uh as we think about writing this report and um and providing advice about how to make that engagement piece more robust. Do you have any um reflections on things that didn't go well because you've been doing it for a while? um things that did go well and kind of you know kind of overall best practices that you would recommend and it sounds like now I can't remember did you have a paper coming out someone had a paper coming out on that so maybe it will be answered there thank you thanks everyone great talks >> yeah thanks for all the questions um why don't we do the same thing and do will first freshen the reflections on lessons learned with engagement Yeah. Yeah. I've got plenty of those. Uh, as you say, I've been, uh, doing this for a while and we've definitely, uh, you know, learned, um, over the past three years. Um, I mean, there's there's so many things uh that we're doing well now that we weren't doing before. I think first and foremost we have a real expert internally that does the work. Um with the right credentials and the right skills. Um I was not person why I was not that person and I remain to not be that person. Uh but um but I work very closely with Diana. I I do think when I don't I don't really want to mention best practices because again I'm not the right person for it but I do think Diana is rapidly becoming um the person who can provide that. I think that the framework I showed in my slides that you can go back and see in terms of the steps um you know that begins with informing but it moves quickly into higher levels is helpful. But I remember her telling me just last week over dinner that there is no playbook for this work. Um I don't I think she would probably push back on the concept of best practices honestly but I don't want to I don't want to put words in her mouth. Some things to reflect on and I think some I think these mistakes are still being made by others. Opaque websites. Um people people in the community will use your website to understand your work. And if your website talks is investor-driven talking about gigaton removals um and pretty pictures then people will not only not get the answers they want but they will end up with more questions um and more skepticism. So, we learned a lot about how we put ourselves forward. Um, particularly on our website. Um, and then other than that, I mean, it's the same old story that, you know, you just need you need to do uh such a huge amount of work. Um, and so you need someone who's dedicated to it and and can do it all day every day. >> Thank you. U Mallerie, you're next. What sorts of marine creatures? Right. So, yeah. So, I have the entrainment question. I want to say I'm not the primary person to talk about this. The engineering of how you pull in seawater for all sorts of different coastal infrastructure is a robust piece of work. You know, there's legislation and there's all sorts of permitting rules around things like what is the filter size of the screen, how often do you have to clean it, what happens with water that's been back flushed. Um, so I'd point you to some of those pieces and we can dig that out of our permit as well, what the specific conditions are. We do take samples. um at that point where we pull in seawater. But for the most part, this this isn't something that we're really too worried about because this is a research pilot to get a variety of different pieces on board. And at the end of um these types of pilots, we really want to move into somewhere where someone else is doing that stuff for us, right? And so we want to think about what are the different types of measurements that are sustainable when we move to a, you know, a commercial site that's pumping vast amounts of water far beyond anything that we're doing here. Um, I also do want to touch on the the community piece. Um, echoing everything that will just said, one thing that I want to say, not a best practice, but a recommendation for folks when they're they're talking with the local community is to come to people with questions about what it is that they want to see. And that's been something that we've done with every group that we've talked with. and you can make minor changes to your process and to your studies that can really um help people feel comfortable with what you're doing and can help them feel empowered to ask you more specific questions. So, for example, we did a rotamine die test. It's non-hazardous. It's red dye in the water, but the community boating program next door runs a youth sailing program and they didn't want their kids sailing through it. Great. We'll do that test in the morning at an off time. We'll work around schedules. trying to make changes that are really easy concessions for us and don't even count as concessions um but present us as a part of the community and not some heavy-handed scientific group that's just showing up to do this work. So, I just want to point that out that everyone we've we've talked to has had something that they'd like to see. And by offering that upfront, it's it's really allowed them to to ask more detailed questions and to get engaged with the work and why we're we're making choices the way we are. Thank you, Mallerie. Uh Jamie, do you want to talk about any theories you have on the cycling and how that might affect future work? >> I mean, so the question has to do with why does the alkalinity of the groundwater change so much and is so variable and like my guess is as good as yours. And I've at this point like talked to as many groundwater people as I can kind of find in proximity and groundwater is just really variable. I actually I kind of stand by this idea that um in the enhanced rock weathering world they could really benefit by if they could do a big enough experiment that we could see it in our coastal waters we might have more information than them because there's I don't see it's very hard to flux weight the groundwater so you get variability in every sample but you but then the variability in that co in that end member is not as big so I don't know how to understand it it seems like the groundwater water interacts with the rock in ways that are like so temporally and spatially variable. And then there's al also um probably denitrification and some sulfur reactions. Sometimes the samples do smell sulfurous. So I don't know. I think we're better off looking in the salt water and then doing mixing curves there. Um and so it's a great question. Um, it made me very curious, but I have more questions than answers as well. >> Thank you. Um, Helen. >> Yeah, thank you. Um, so uh Jamie, you you mentioned baselines and um that you would have preferred a longer measurement period than you had available if I understood you correctly. Um but how long do you think uh is like a bare minimum time to make the measurements for to establish baselines for ocean alkalinity enhancement? Would it depend on the location or duration of the OE deployment? Um and also how how useful is the concept of baselines and if any of the others have any comments to this then I'd be happy to hear them. Thank you. >> That's a great question. I think it really has to be right sized for what you're doing. So like maybe um in Adam's experiment it was fine to just be out there for a few weeks or what whatever they had because they had such clear in patch out of patch from their roam tracer and it was a small but still big relative to the variability probably within the patch that they were looking at. Whereas our experiment was this small perturbation um in over that was going to be seen also groundwater is laggy and slow and and and the soil integrates the the signal. So it was like this slow small release in a background variability that we didn't know. I actually think the process of discovery has been amazing. Like did you know there was a 50 microar seasonal swing in total alkalinity in the in in like Rhode Island Sound? I don't know that anyone knew that before. So we don't it it really speaks to like this being a process of discovery and really shared with the oceanographic uh research endeavors that we have going on. And so I think um knowing what I know now, I would I would say you'd have to rightsize it. So for my system and our perturbation, I'd want a whole seasonal cycle, like a whole year before we did anything, but that wasn't going to happen. Um, but that might be a very different answer for these other systems and perturbations. >> Thank you. >> Yeah, my hand. If I could just weigh in quickly, I I totally agree with Jamie and I also think that, you know, the other the other useful bit of the baselining from our perspective is yeah, we we were sort of doing this in patch out of out of patch comparison, but we also had, you know, 20 plus years of historical data in the region to help us understand what this site was going to do. Um, predict, you know, where a best location was. So from a site selection, from a, you know, community engagement perspective, etc., those long-term, you know, chemical, physical, and ecological baselines have been really, really critical for us um to to to be set up to the point where we could conduct a successful experiment. So I'll just say like, you know, from that perspective, too, we learned so much about how the system works through this baselining um data collection. Um and the more data the better, right? And the more successful a deployment is going to be. It's obviously a very different um mode of operation from you know a company who's looking to operate 24/7. But you know that's not to say that I'm I'm sure Will and Mallerie put a lot of thought into choosing those sites partially because they they knew something really detailed about the region and the oceanography through all of this dedicated baselining work um from the academic institutions and the and the agencies in the area. So, so those baselines are absolutely critical and especially in these coastal zones are are really important to to have that data and to understand um when it comes to site selection too. >> Thank you. Um Kristen, >> yes. Hi everybody. Thank you for the presentations. Um I had a question. Um I guess it's more directed for Aaron um but um others might have perspectives too and I was just curious in one of your last slides Aaron you had a point about um you know the the relative utility of smallcale experiments and large scale field trials and I wondered if you could just talk a little bit more about any ideas you have um for strengthening sort of those synergies between smallcale experiments and the large scale field trials. um for OEE but you know I guess thinking more broadly to other types of MCDR as well and then um you know how those small scale experiments I think you said something about better design of those to fill gaps. So um I'd love to hear about that too if you have thoughts. >> Yeah. Um I think probably a really good example is probably actually the work being done with planetary and delhazousy like you've obviously got the large field trials and planetary and delhazy learning from them but then you've also got sort of I mean at Delhausy they've got masters students they've got PhD students they've got posttos that will be working on these smaller projects so they can kind of get ideas from these field trials and obviously they don't want to change whole field trials to answer small scale like well answered questions that can be answered on a small scale. So that I think there's just a really good niche there where these other researchers can come in and start to fill those gaps and I think they're quite well positioned um over there in Nova Scotia to do that because they're so close. Um however like across the field as well um we've got a lot of uh obviously discussions and communication between partners and things like that um which is really beneficial for us and that's that's how a lot of the ideas come about at UTAZ um you know we've got sort of our professors and stuff there talking to other people coming up with these ideas and um like for the experiment that I conducted it just sort of came about from some work that other people had done with light and these ideas that you can sort of get these thinness curves and things like that once you start to do some high throughput experiments, you know, sort of 70 different conditions, which is something you just can't quite do in these larger trials. Maybe if you're looking from like the dispersal point out, you can kind of get a gradient, but it's not, you know, a single species or something like that. Um, so in that regard, I think just instead of doing these like repetitive small scale sort of community experiments or something like that, just be being a little bit more selective and really sort of thinking about the niche that you can fill um in regards to the larger scale stuff because that's inevitably the direction that we're all sort of trying to get to. >> Thank you. Uh, thanks Aaron. Um, hi Gabby. >> Hi everybody. Um, so my second question is also mostly for Erin. Sorry to put you on the hot seat for the hot seat for a couple questions in a row, but I would be curious to hear from other panelists how this played out and in your research as well. So Erin, I know you mentioned that in moving towards kind of best practices for the community doing these kinds of um ecosystem response experiments to move away from these higher threshold or unrealistic kind of alkalinity thresholds and and permanent chemistry kind of pertabbations. I know that regulatory community really cares about kind of the LCLD50s um moving forward. So I'm curious how you reconcile that in your framework and if you're thinking about bringing these regulatory parties into kind of the creation of this best practices guidance and yeah then from other panelists seeing how that kind of balance of um maybe the community concerns of realistic um perturbation levels versus the regulatory concerns of those LCLV50s would be great to hear more about. Yeah, I mean I'm definitely probably not the best person to talk to about regulatory and um sort of frameworks and things like that. I have been fortunate enough not to have to deal with a lot of that. I kind of just get to sit in my lab which has been great. Um but I think when I'm talking more about these unrealistically high levels, it's sort of when you're in a lab doing an experiment on a single species and putting it underneath. I mean, I say this, but I did it in my experiments with really high levels. Um, but that was sort of to gain a mechanistic understanding of what's happening with the phytolanin and to determine um what carbonic chemistry parameters they're responding to. But it's more in terms of these experiments where you're increasing alkalinity to sort of like 500 5,000 micro moles or things like that, especially in a scenario where it's already equilibrated. it's just not exactly it's not something we're going to see or at the moment doesn't seem like it's going to be occurring um in field trials. So I think instead of sort of targeting those extremely high um alkalinity levels in the lab, it could be more beneficial to be staying around the more realistic possibilities. Um I mean that's not to say that there isn't a need to push the boundaries and see what happens because that is something that's going to be important. We do want to know if say there is an accidental spill or if there is an excess pumped into the water. We want to know what's going to happen. But I think at some point we have to sort of narrow our scope to what's realistic and what might be implemented in the near future. If we want to sort of answer the questions before people start implementing this. Um because that's the real thing at the moment is things are progressing so quickly. we need to stay ahead um rather than having the trials and the um deployment sort of occurring before we have a complete understanding. Um hopefully that sort of answers it but I think some other people have some comments. >> Yeah, Jamie. >> Yeah, thanks. Um I I want to raise two things. First, um being involved in graduate education, um there's a real reluctance. I I've seen it now firsthand. I feared that it would happen and then it happened to me in a real committee meeting where a student said, "But I have to like I have three I only have three misoccausins and I have to hit at least one of them really hard or like what if I don't see anything?" And so there's a real tension for students trying to publish and get their dissertations done to show a response. And so I think um that just speaks to all of us like who do paper reviews and things null results have to get through and we have to like be compassionate to students who are working working through that. So I just um I think that's another tension just to be aware of in the field if we want to push them to do these very small perturbations. We have to be ready for to get a little bit flooded with a lot of n you know possibly null results and if they're not then that that would be a big story if you get you know biological responses. The second um comment and maybe this is why they're Mallerie and Will had their hands up is um if it there could be co-design of these misoc experiments so it could really match what Will sees or Mallerie right at the outfall 100 meters from the outfall you know a kilometer and so on then that could be a really cool way to um contextualize an experiment that's that's no longer hypothetical it's like really trying to mimic the world. So thanks Thanks. Um, Will. >> Yep. Took the words right out of my mouth, Jamie. Um, we're doing that. We're we're getting a lot better at that now. Um, you know, folks are coming to us and asking us what what are your perturbation levels and and testing at those levels. So, I think progress is being made. So, I appreciate those who are yelling about that stuff. Um, the LC LD50 part I think is really important um to think about that is what regulators care about. Um and the so I I I and I think that is important for for our type of OA. You know, it really boils down to the feed stock. You know, is this material going to be safe? Uh you know, that's not that's not everything, but it's certainly a lot of of demonstrating or or or feeling okay that this is a safe operation. So, testing that feed stock and and and one really good way to do that is to to see what kinds of concentrations start to have adverse effects. Maybe not 50% mortality. you can there are other levels before you get to that point that you can detect. But that's that's a huge part of what we do. Um doing it on certain species is less useful because those species are very resilient. Doing it on sensitive species now that are local to the area now you're talking about now you're now you're hitting maybe the right the right mark there. So that that's um I think there's good progress being made. >> Thank you. Um, we've got Terry and then David and then Dave Carl. Um, hopefully we can squeeze these three in and thanks everyone for staying on with us. Um, >> thanks all. Really great talks. I appreciate the engagement content as well. It's been super helpful. Um, will you were just speaking to this, but I thought maybe if you andor Mallerie or others had any more. I wanted to ask about the larger life cycle challenges that you're encountering. So, one might be the quality of the feed stock, but anything on anticipated difficulties uh sourcing the feed stock or in Maller's case dealing with the HCL that you've encountered so far at any level. I mean, it's early days, but >> um I mean certainly certainly that will be a challenge certainly at the beginning, right? So, uh, I think we're already starting to see that industries that have, um, alkaline feed stock piles, you know, the more the more that this becomes mainstream and the more we can point to real life application and and demonstration that this thing is actually a thing and not just, you know, a madeup story. >> I think that will that will start to unlock this and we're already seeing evidence of that. you know people are people are reaching out to us now and saying hey I got this feed stock you know apparently you can generate carbon removal with it so so I think that will be a positive step but yeah I mean colllo so finding the feed stocks and colllocating it with your site is is a huge part of what we do and it's very hard right now but we're seeing signs that it will get easier >> and I'll just add on to that um some other things we think about finding locations that have a relatively green energy grid that's really important for us especially at the pilot stage there. Like Will said earlier, there's no profit in this business right now. We're trying to demonstrate a technology and eventually it will scale. But if those early projects are burning more carbon than they're actually removing, then that's a challenge for us to convince investors and philanthropies and granters that this is something that we really should invest in in research. Um I'm surprised that this is actually the first acid related question, but that's another piece is that um ES technology isn't the only type of OA that produces a byproduct, right? And so colllocating with places that can offtake that for industrial uses for other purposes or just get rid of it through some sort of neutralization process that is again low low carbon emissions is really really important. And so um when we're trying to come up with sites where we can work in the pilot stage realm, it's going to be very different than when we're looking for commercial integration that makes this scalable. And so I always want to repeat that because some of the questions that we get on pilot scale um papers and publications and conference proceedings are focusing on these larger scale questions that have a completely different research track to get through them. And that's why we need to do this work in in concert with industries because if we can't scale up OA in general then what are we doing? >> Yeah, many thanks. >> Thank you. Uh Dave Seagull. Um just to um just a a kind of naive set of questions because that's what I'm good at. But the um it seems that um we have sort of two basic methods where people are talking about how to do the the process want us to use an existing discharge and all the discharge permitting and all that sort of stuff. So I have a question is can that scale up globally to be something that's CDR worthy is you know something approaching a gigaton of C CO2 per per year. And my um second question is it you know it's obvious that that those sort of uh that using discharge permits it's either either on ships or in power plants or how however you you want to do this can um can push things forward fast because there's a discharge per permit in place and you you know what to do from a regulatory po point of view whereas in the kind of open conditions that you know Adam or Jamie were doing or what Nest is trying trying to do with beaches. Um, it seems more it seems more complicated and harder to get all the sort of buy in and all the other things that are going on. I just want some reflection on that from the panelists and I know Yeah. So, I'll shut up and you guys can talk. >> Yeah, I'm happy to start that one because we worked um locally in Washington under both regimes. The work that we did at PNNL was under an existing facility outfall permit and it's one that would be familiar to a lot of folks who have looked into the space. We couldn't discharge anything beyond a pH of nine. And the site that we're working on at MCOMA is different. We've sought a specific permit for the purpose of doing what we're doing at an elevated pH beyond that. And there's different reasons why we go one route or another. Permitting a facility like PNL's wastewater treatment plant is slow, right? And so for us to be able to work under that regime advances some aspects of the research that we're doing, but we're really limited by seeing the signal of OA that we put out into the water. And you'll see that in the paper that's coming out soon. And so that's something where PNL, if they're interested in expanding their research, may seek other ways to permit that are are more flexible for doing MCDR research. And it's important to remember that when we're trying to scale this technology, there may be a lot of different regimes that we work under. We might not need a new permit to work under an existing coastal outfall that's much much larger than we are because we're just a small stream putting into a massive industrial outfall. But then as the technology scales overall, maybe we do want the flexibility. And so understanding and stress testing that permit pathway is really really important at this stage especially if we're trying to site new locations that are advantageous for one reason or another. >> Yeah. Yeah. Um I think the basically the answer to my questions for you David are yes and yes. um the discharge the discharge scalability question I think there's been some some publications that have come out to show that simply discharging at the coast can can reach gigaton scale um you need a lot of pipes but there happens to be a lot and as we um as we prove this technology out building pipes um short ones that are coll-located to a source is not out of the question as well can't do that now because it would break your carbon budget but I I think the basic question of can the coastal approach scale I think is is yes. I think that's backed up pretty well. And then yes, I do I do think this is more complicated in the open ocean for many reasons. Um which is why we're doing it the way we're doing it. >> I I would just I this is a very quick amendment. I think the modeling studies that have showed the coastal capacity it is they do kind of get to gigaton but they aren't changing the alkalinity by a reasonable amount but in every grid cell near the coast this isn't like it's not like if we put it in every discharge that exists so I think that's what will saying if we built a lot of pipes the equivalent of in a model raising the TA in every coastal grid cell in the globe gets us close to a gigaton I think so it's it's a big task Yeah, >> can I just just say something quickly about global shipping and sort of you know that's another you know Sarah Noas yesterday was talking about sort of reusing infrastructure and and the global shipping infrastructure is a clear other you know set of um existing you know industries supporting industries and infrastructures that um have a clear incentive to become carbon neutral because the IMO has that like this industry has to become carbon neutral by 2050 or whatever. So, um I think these are two sort of parallel pathways. I I would be very hesitant to start like competing between them um because I think both both options are still very much open and should be pursued um in terms of sort of reaching this this um this climate goal. >> Thank you. Um I think we're almost out of time. We have one last question um from Muhammad Hashe. >> Hi everyone. Um great uh presentations and discussion. Um I have one question and one quick comment. I'll make it very short. My question is to Will um about the TSS the total suspended solids. So it seems that you measured that to ensure that you stay below a certain level given the permit that you have. My question is, do you know if some of that is precipitation, secondary precipitation? Can it be that or is it only the uh the mineral that you dispersed? Uh my comment is about the um I don't know if I have do I have do I have time for a comment? >> Yeah, go ahead. >> Okay. Yes. Uh very quickly about the idea of um basically the perturbation and the amount uh and whether the experiments are relevant. Um, I think it's really hard to answer this question currently because we don't really it's there's no one method that we're all using. There's just so much variability. There are so many different ways of adding alkalinity. There are so many different conditions and places in the ocean. Um and and I so I think at this point it is really what is really important is to make sure that the experimental design is is done in a way where we cross that boundary where we we kind of like uh show what is safe and what is uh efficient way of dispersing alkalinity. So last year, Adam and I conducted some experiments where we were looking at mineral precipitation as a result of alkalinity enhancements and we had a very lengthy discussion of what are the values that we should use and I think it was a really difficult decision to make because there's just no we we're at this stage where we're doing these uh you know experiments where people are doing these different kinds of alkaline enhancements. So I think it's really important to make sure that we cover that range and and I think that way the experiments can inform the deployments and not the other way around. >> Thank you. >> I just I saw Scott come on video. I pausing for a second in case we need to wrap this up. >> Well, that was why I came on video. Um, we've we've reached 2 o'clock. I want to thank all the panelists, you know, for a wonderful, insightful session and just remind everybody that we will be coming back tomorrow again at noon Eastern for the final day of the public session. Uh, Kelly, did you have anything you wanted to add? >> Uh, no, just just thank you on behalf of the whole committee. Um, this has been a fantastic discussion. Um, and thanks for staying on and answering all of our questions. Um, we really appreciate you. And committee, um, in 15 minutes we'll log into our close session. Um, so see you then. Bye everyone.