Safe and Effective In-Situ Remediation Best Practices
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What’s the minimal geochem data I can collect and still have something reasonable on which to make decisions?
Well, I would say that, if you’re just starting out, perhaps you’re a little low on budget, you know, at least collect nitrate, total and dissolved iron, sulfate, methane, and, you know, if you still have a little money left, carbon dioxide, and or alkalinity. I think that’s a good start for a petroleum site. For chlorinated site, I’d probably lump on to that total organic carbon and perhaps chloride, just as a starter, and you can build on it from there.
Can you give an example of how an injection subcontractor did not understand the local soil and will add up the products being injected, and how that proved to be a problem on the site?
I think that’s very important. Well, I’ve seen that in a couple different ways. First of all, I’ve seen contractors that perhaps were not as accustomed to working would show up on site, with the wrong direct push equipments, something that’s not gonna be robust enough for the geology that we’re working under, and subsequently waste a whole lot of time trying to push through and get fluid into the subsurface. So that’s one way it can be a problem.
The other one is a lack of understanding of the chemistry, and the real ways to finesse the pressure, and the flows, too much is too much. And too much of a hurry usually results in bad results, a bad outcome on sites. So I think that’s another way that I’ve seen that manifest itself, where you’ve got a contractor who doesn’t necessarily know the chemistry, and starts to go too fast, and the next thing you know, you’ve got product pushed into monitoring wells, or daylighting at 10 different locations, and really creating a problem.
Dane: Hello, and welcome, everyone. My name is Dan Menke. I am the Digital Marketing Manager here at Regenesis and Land Science. Before we get started with the webinar today, I have just a couple of administrative items to cover.
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Today’s webinar will focus on Best Practices for Safe and Effective In-situ Remediation. With that, I’d like to introduce our presenter for today.
We are pleased to have with us Mr. Jack Sheldon, Senior Remediation Specialist at Antea Group. Mr. Sheldon is a remediation expert with over 35 years of industry experience. He has specialized in the field application of various types of bioremediation and chemical oxidation and reduction systems, with personal involvement in 22 first type remediation projects in their respective states. He has completed remediation projects in all 50 states, and several locations abroad.
All right. That concludes our introduction. So, now, I will hand things over to Jack Sheldon to get us started.
Jack: Dane, thank you so much for that kind introduction. And thank you to Regenesis today for hosting this webinar. Also, thank you to all of you that have taken the time to join out there. I hope that when you leave today, you’ll feel like your time was worthwhile, and that you picked up some interesting information.
So, in the past, I’ve had the opportunity to present other webinars for Regenesis. And couple of years ago, I presented on how to monitor sites in which Regenesis products are utilized, what do the monitoring programs look like, and how do you interpret results from those. Last year, I was able to present a webinar on a case study that involved multiple Regenesis products, and Regenesis field services, and how combined remedies can be effective in leading you to a solution on a site.
Well, today I’m gonna present something that’s radically different, and I hope that this works for all of you. It’s a thought process webinar, and it’s a webinar that’s gonna focus heavily on safety. And I can tell you from experience that thinking and safety jive well with your interaction with Regenesis. I’ve had the pleasure of working with Regenesis for a couple of decades now, over a couple decades. And we’ve had a tremendous amount of collaboration, noodling on some pretty difficult problems, solving those problems, and working safely while doing that.
So, again, today’s webinars is gonna focus heavily on project thinking, and on safety. So the objectives today, I want you to leave here and be able to think about key project issues. The more thinking you do, the more planning you do, the better your project is gonna be ultimately.
I also want you to look at the tool I’m gonna introduce to you in just a moment, and use it as a tool to get your project team to buy-in to the overall path forward on a project. There’s nothing like having a project team that works in concert with one another. And that’s not only internal folks, that’s also the client, the end user, it’s also the subcontractor, and that can very well be Regenesis, and Regenesis Remediation Services in a number of applications.
I want you to here and think that you have ways now to improve project performance and make safety paramount in all your projects. And then, lastly, by using a project checklist, it’s a great way to support interaction with Regenesis and its field service arm, RRS
So the checklist. So, any remediation vendor out there that has a product, likely has some type of a site evaluation form that you can fill out. Often those are electronic, they’re online, you can fill in your information, that provides the vendor enough information to help you make a selection of a technology on a project, and then help you work through a design to get something in the field. Well, that’s great, and that serves the beginning of the process very, very well. But I contest that maybe some more information is needed.
And so, we at Antea Group, we have built a system that allows us to ask some very distinct, very critical technical questions, and very distinct and critical health and safety questions. We’ve done this for mechanical systems. We’ve done it for excavation, but we’ve also done it for all of our in-situ systems. And I can tell you, we do an awful lot of chemical oxidation projects ISCO, year in and year out. And this form, this checklist, has been such a critical tool in that process, because it’s shaped our thinking, it’s allowed us to ask tough questions right from the start, and it’s allowed us to see our projects succeed as a result of having good information.
So, if you look at the circle to the upper right here, where my cursor is pointing, you will see that things are divided up into select design, and execute, that’s select technologies, design a system in the field, and execute or implement, and then follow up that implementation with monitoring out in the field of an in-situ system.
You’ll also notice with the small circle here in the middle, that we have categories of staff listed including a reviewer. What this is in our checklist is a little system that we use so that each of these individuals assigned to a specific project, can sign off, and they buy-in to a particular response in a given category.
And then to the right here, in the larger circle, we have various line items that are listed through the select process, through the design process, and through the execute process, that point to pieces of information, that ask questions. They don’t show it here on the slide, but if we were to extend this form out horizontally, you would see that we would have sections in there for each of those project team members, to incorporate pieces of information. So we have a running dialogue, and a planning tool. Ultimately the person assigned to review the project, and all the technical accuracies, and the safety components, can look at that dialogue and be assured that the project team is onboard, and that they’ve truly fleshed out the information that’s critical.
So, just looking at some of them there, remedial objectives have been clearly defined, right? That’s the first line out, and isn’t that so important when you’re doing an in-situ remediation project? Have we identified the barriers to closure? What are those going to be on any given site? Dropping down here, do we really understand what all of our constituents of concern are? Do we know what our VOCs, or SVOCs, or TPH, or chlorinated solvents? What do they all look like in the process? What do we know about the metals that are present on our site? Do we have them? Can we just have background metals? All that information is pertinent in the process.
And then in looking at the last line item there, how about significant NAPL present on a site, or a history of NAPL, wouldn’t that be important in terms of mass contribution? So these are things that are part of the process.
And so, what I’m gonna do now is I’m gonna jump into an actual site, one that we at Antea Group did with Regenesis. And this is a site in Seal Beach, California. It was an in-situ chemical oxidation bioremediation project. So, combined remedies used on the site. It’s a site that achieved closure last year, one of seven, where we used different combinations of Regenesis chemicals, and were able to achieve closure on those sites in Southern California. So, when put in place, the process can really work.
So what do we glean from those simple bullet items that are there? First of all, we know we’ve got a service station, so that triggers some thoughts in our minds, says, you know, “What kinds of things go on at the service station?” You know, there’s car maintenance, there’s cars that are leaking oil, that park and parking spots, there’s gasoline dispensing, there may be assorted other maintenance outside of individual garage bays that leak fluids onto the ground. There’s numerous activities, there’s vehicular traffic, and that can certainly be a big component.
We know we’ve got benzene, MTBE/TBA, so we know what our constituents are that we’re dealing with. We know something about them, we know that we can biodegrade those under certain scenarios, we know that we can chemically oxidize them under certain scenarios. We know we have groundwater impacts, if you look at the first bullet, but we also know that we have remaining saturated sorbed impacts. And that can be a critical factor because that’s gonna contribute to your dissolve phase going forward.
Looking at the second bullet, we know we have silts, sands, clays, might imply some sort of a layered type scenario on the site. We know we’ve got fairly great heterogeneity that’s present, so we’re gonna have to contend with that as part of the design of our process. And we also know that we have limited plume movement. So what does that tell us? We have perhaps some, sort of, a bathtub type scenario, where our plume is relatively stationary, and migration is not gonna be one of the key issues that we’re gonna have to deal with.
We also look at the concentrations there, benzene, MTBE/TBA, Total Petroleum Hydrocarbon as gasoline, and we see what some of those general concentrations are. And we know that those concentrations are not particularly high, and that they’re very, very manageable concentrations, and potentially with both chemical oxidation and bioremediation, we can get a successful result.
We also have some field data that tells us that we’ve got, on average, about a milligram per liter of dissolved oxygen. And that’s very important as well, because that tells us that we can probably tip that up a bit more and create a more robust aerobic condition on the site. If it were much, much lower than that, then maybe we’d give some consideration to an alternate approach, as opposed to an anaerobic bioremediation. So, five, six simple bullets here and already we have a wealth of information. But the bottom line is, in order to really round out our checklists, we need more.
And then we get to something like this. I chose this site figure for a reason. It’s messy, it’s crazy, it’s chaotic, and it’s exactly what you and I deal with on each and every site, or unless you’re working in a vacant lot. Look at all the things that are occurring out on this site, this is the gas station site, right? And that’s, you know, it indicates where canopy is present, our dispenser islands, down here we have an underground storage tank which undoubtedly has some piping that comes over and feeds the dispenser islands. And look at this, we have some remedial system piping here as well. So another conduit in which things can flow into. We’ve got a series of lines, blue, red, yellow. All of these are subsurface utilities, things that are gonna make an in-situ approach challenging.
And then, to the right of the screen here we have a driveway. We have a sidewalk, and that creates its own set of challenges. That means there’s gonna be traffic that’s gonna be moving through the area that we deal with, that we treat.
And then up here, to the top of the screen, we have a planter, and we have another planter, and we have a gas meter, so that tips us off that we have gas coming into the site. Planters are very interesting too, because they can oftentimes contribute quite a bit of nitrate into your site which is very interesting. And there is live vegetation there, and that’s another consideration when working on a site like this. And all the dots that you see there are different rounds of injection that’s taking place. I wanted you to see that, beyond just the infrastructure, beyond just the logistics of the site, because that shows us, shows you, you know, well, that has to be worked around when an in-situ system goes into place, you know.
You’ll notice in some areas of the site, like up here in the upper right corner, the points are more spread out when we’ve got some challenges. They’re more spread out here in the middle where we’ve got quite a bit of infrastructure. And yet they’re closer in density in areas of the site where we don’t have as much. So, all those things are factors, in terms of creating the proper environments in the subsurface, and which to create treatment.
Every site has closure criteria, I’ve just listed a series of them for a site here. Yours may be altogether different. You may be in a site where your target benzene content…You may be in a state, I should say, where your target benzene concentration is 3 micrograms per liter. You might be in a state where it’s 5. You might have a risk-based scenario, where your target benzene concentration is 250 micrograms per liter. So, your scenario for closure is gonna be different site to site. You may have environmental covenants in play, you may have all sorts of other issues, such as the ones listed here that may be critical factors, as you now get into the select design and execute for your remediation system.
So, let’s dive into selecting technology. That’s the first of our three critical areas in our checklist. Now, I mentioned before we were dealing with a service station site. So the first thing that that should trigger is, “What type the site am I working on? What are the typical sources of impact on that site? What do I normally see on a gas station site?” Now, those of you out there, you know, we have a broad array of people that are online today, you might work on chlorinated sites exclusively, so your thinking is going to shift to a manufacturing site, perhaps, you know, a site where, you know, they’re making a particular type of product, or they’re degreasing some sort of part. And so your sources are going to be different than what you would see on a gas station site.
But this is probably your first critical piece of information, is to understand something about the type of site you’re working on. You might be working on a chrome-plating facility, and you might ask yourself the question, “Well, what kind of chrome plating do they do? Do they use Hexavalent chromium or do they use Trivalent chromium? And then, what happens to those when they get in the subsurface?” But again, the point here being that, at this particular stage as your selecting technology, this is the time for you to generally get up to speed on the type of site that you’re planning on remediating.
Well, on the heels of that, you’re gonna go through a series of historical searches, and you’re gonna go through a series of data collection, and you’re gonna build yourself a robust site conceptual model, conceptual site model, call it what you will. And a conceptual site model is not three sentences that you write on a page, conceptual site model is a thorough understanding of the goings on, on the site. “You know, what creates my source of contamination? Where does it go when it enters the subsurface? What is at risk? What sort of factors are acting upon those chemical constituents when they get into the subsurface?” And does, kind of, goes around in a circle for a reason, because once you gather that information, you build that conceptual site model, that certainly dictates your conceptual site model, and then what you’re gonna go forward with as your understanding of the site. The more you skimp on information, the less complete this is gonna be.
And I’ve had many a person say that, “You know, a conceptual site model is way more than pages of text that describes certain scenarios. A conceptual site model has to be so good that you can define the complexity in a simple cartoon.” So keep that in mind, a good conceptual site model, is such that you can define all the complexities in a simple picture, simple cartoon.
So, as you’re going out, and you’re gathering information, you know, I strongly encourage you as a best practice, collect good quality field parameters. You know, I beat this horse dead in many a webinar, in many a presentation, but there’s something to be said for somebody that can go out to a site with a probe, or with a flow through cell, and can gather good quality field parameters, you know, pH that make sense, dissolved oxygen that’s not 37.6 milligrams per liter at every well, but a real number that you can actually come back and interpret when you get it back to your office.
So the practice of collecting good quality field data is so, so important. You know, they seem like simple parameters, but conductivity, pH temperature, oxidation reduction potential, dissolved oxygen, when you have those good quality parameters, now you can start to make heads or tails of what sort of conditions exist at your site that’s gonna aid your technology selection.
You wanna collect geochem data, right? Lot of sites I’ve seen historically, you go out, you get your contaminant data, well, maybe you get your field parameters, but you say, “Well, I don’t wanna spend money necessarily on those other things.” Well, I think you’re missing the boat. You’re missing out on some incredible information that also can shape your thinking on the type of remedial product that you ultimately select for your site.
You wanna know where your site lies on the Redox ladder. You know, what kinds of microbes might be in play there? And they always are in play. Sometimes they’re doing good things and sometimes they’re not doing good things. And I think you wanna know that as you go forward.
You also need to know if one or more parameter is out of whack, if something looks unusually high, or unusually low based on the scenario. All these things are important, they contribute to your conceptual site model, and they’re also important after the fact. Should you put a remediation system in place, and things don’t go according to plan, when you’ve got a complete data set, and you have field parameters, geochem, contaminants, all those things together, now you can start to make heads or tails in your troubleshooting process. So, collect geochem data.
I’ve also beat this one to death and many a webinar and presentation, but maybe it’s because I’m a microbiologist, and this is my passion. But I think you’re also missing the boat if you don’t collect some sort of microbial data. We have so many robust tools that we can use these days to get better data. We have different types of sampling devices as you see there, different ways to collect those samples.
And then, in the box there with the bullet items, we have different types of analysis that give us different levels of information. “Do I just wanna know some general things about my microbial population and the numbers of microbes that exist? Or do I wanna get deeper into it? Do I really wanna understand the degradation mechanisms that are in play at my site? And do I really wanna prove that? Do I need to go to a level that I need Compound Specific Isotope analysis, or Stable Isotope Probing to actually show someone that I’ve got degradation occurring at the site?”
And then, there’s other levels that you can drop to again. All these analyses are available to you at different price ranges, and that will be very helpful to you as you make your technology selection, you know, build out your conceptual site model.
And then there’s that wide array of investigation tools, and other test methodologies that exist out there. You know, many of you use CPT on your sites to get information on mythology, and there’s uVost, MIP, Hydraulic Profiling Tool, Water Injection tests. All these things can be valuable. It’s incredible how much information you can get all out of a single day’s worth of probing at a site. And you can put in a lot of holes in a single day and collect a lot of data.
And of course, I mentioned earlier, field parameters, geochem. Treatability studies, I’ll talk about in a second. But there’s other things you can use to gather information on a site to make your technology selection. It can be Tracer Studies, you know, Grain Size analysis, slug testing, pumping tests. The list goes on and on. Soil cores, if you’re more old school like I am. But there’s lots of things that can be availed to you, that can help this selection process along. And, by all means, don’t forget to use Google Earth. Don’t forget that very basic and simple tool as a great way to look at your site. Even if you haven’t had opportunity to visit it yet, it’s a great way to visualize it. Look at the surroundings to the site and gather information that way.
And then, lastly, as part of your selection process, another key factor is the chemistry itself, right? Perhaps you’re someone on this call that’s used every single Regenesis product, maybe you’re someone that’s never used a Regenesis product, so just a very, very brief reminder here. RegenOx is a moderate to strong oxidant that you can use on sites. It’s infrastructure safe, it’s sodium per carbonate based, leaves behind some residual oxygen, which can be an added bonus, gives you an opportunity to bioremediate, bio-polish on the tail-end of your oxidation. We’ve grown accustomed to using RegenOx Part A as a very nifty little desorption mechanism on sites. It has some very interesting surfactant properties due to pH and other components of the chemistry, and can make for a nice little desorption chemistry.
PersulfOx being an all in-one product that we use, a strong oxidant, something where you can add it, it’s self-activating. That’s a real big plus to those of us that have to add chemicals in the field. Always easier to add one chemical, as opposed to multiple chemicals, and trying to marry them up. So, a little bit on those chemistries.
And then, ORC Advanced Oxygen Release Compound, a means by which to get oxygen in the subsurface, build a more robust and more uniform aerobic condition. And, you know, when you put oxygen in the ground, you first get increased numbers of microbes that’s called growth. The densities of them increase, and then as a result, the ability to degrade more and more mass. The rate at which to degrade that mass, that’s the beauty of adding oxygen to a site.
Then lastly, certain sites PlumeStop, maybe the chemistry that you’re looking for, Liquid Activated Carbon, a means by which to retard the plume to create absorption site by which contaminants will stick, and will become embedded within that matrix, and then subsequently able to be biodegraded as that moves to the interface of the carbon particles. And oftentimes we find PlumeStop used in barrier type configurations.
So, all those chemistries are possible. I haven’t even addressed the chlorinated side of things today. You know, I started with a petroleum site, so I, kind of, stick to that theme as we go forward. But certainly, there are lots and lots of chemistries that are available on the chlorinated side as well.
All right. So we’ve moved our way through selection. So, I think I made the point, you need robust data collection in order to make selection of the appropriate remediation chemistry, and products that you’re going to go forward with. So now, you’re at that very critical stage where you have to design something that’s going to go into your site. It’s gonna go into the field. So, what are some things you need to be thinking about?
Okay. Well, first of all, in the case of Regenesis, and others that are out there that sell remediation products, there’s often vendor design software. And you can work collaboratively with your vendor to go back and forth, and work through the numbers, you know, work through the volumes of inject aid you’re gonna need at a given site. Work through the number of points that you’re gonna have out on that site. Work through the best way to apply chemistry to the subsurface, be it wells, or galleries, or temporary points, or direct push points, or maybe soil blending might be the best way to get the chemistry in place.
Don’t skimp on advice from other subcontractors as well. Your driller will oftentimes have a tremendous number of insights because they know the local geography, they drilled in that terrain for many, many years, they have in-depth knowledge of particular tooling. And their insights can be incredibly valuable in addition to just the advice you get from your remediation product vendor.
Revisit your Mass Calcs. Probably the single greatest way that we, as consultants, miss the mark on sites is because we have a poor understanding of the contaminant mass that exists. You know, you really need to look at that issue critically, you need to run the numbers, you need to have enough sampling completed that you can get a good mass calculation. What’s in the soil, what’s in the water, maybe there’s thin layers of product that exist, or seems of products. You know, all these things contribute. And so the more knowledge you have in that area, the better your designs are gonna be.
Look at photos, visit the site, take a good hard walk around the site, and look at all the things that appear.
And then, finally, when you’re ready to lay out a design for a remediation system on paper, you know, start thinking about, “How am I gonna apply this? What’s gonna be my sequence of application? Am I gonna start on the outside of my plume and work my way in to the more heavily impacted area? Do I have to work in an area at the site first, because there may be some, sort of, property transfer that’s gonna occur, and I have no choice but to start there? Also, maybe I’m in a scenario where my site has certain hours of operation, I have to work around that. So that’s gonna dictate how I apply material in the subsurface.”
“Also, you know, what kind of effects do I expect from groundwater advection? Once the material goes in, how do we expect it to distribute in the subsurface? Do I expect it to get hung up, and take a long time to show up in my wells, or do I really expect a rapid result to something that I can see very, very quickly?”
How about the vertical component? Probably more chemistry, more remediation product is wasted when people don’t understand the vertical component of an injection. Way too much product gets put into layers or vertical horizons that don’t need it. Put it in where in fact the contaminant mass lies, or where there is contact with a matrix, where matrix diffusion, back diffusion may be critical. Those are important points.
And then think about the obstructions in the subsurface. The photo on the bottom right of the slide shows you, in the white, some areas that were envisioned for placement of some injection locations, and the red shows some infrastructure that’s present in the subsurface that may dictate the movement of those injection points to another location. So there’s certain amount of standoff that has to take place in the field, whether that’s five feet, whether that’s 10 feet, maybe that’s more in some cases, and that’s a critical component of your design.
Oh, how about treatability testing? All right. Oxidant Demand Testing can be very important number to have as you’re going into an ISCO application. Yeah, you can use default values on sites. I mean, that’s commonly done, but, you know, I like to collect real data, I like to pull sample from an unimpacted area of the site, send it to the lab, look what my natural oxidant demand looks like, and then add in my contaminant mass on top of that, and figure out my loading of oxidant that’s needed.
Or maybe your site needs some sort of Jar Test or Batch Test, where you’re looking for just sort of a proof of concept that, “Yeah, this chemistry is really gonna work with the soil, and with the groundwater, and its constituents at my particular site.”
And then, to the right here, on the slide, you know, maybe a Column Test is in order. Maybe, you wanna look at the flow characteristics through a cell. Maybe you wanna set up a column of Plume Stop, and look at absorption isothermal, and just see how benzene sorbs, or how TCE sorbs, or how Chlorobenzene sorbs. Any of those things are achievable through laboratory tests.
And I would say that laboratory testing, treatability testing should not be forgotten. I think 25 years ago, we did bench tests routinely, pretty much every project. Now, we do it perhaps a little more selectively. But we do it for a purpose. We can get really good information out of it before we actually go to the field.
Earlier, those fancy tools that you used for a high-resolution characterization, produce graphics that look like this, that can really clue you in on the vertical components that you need to pay attention to. You know, your sand zones, your clay zones, again the stratigraphy is so, so important. Understanding where mass is moving out of sight, understanding where diffusion may be an issue, you know, understanding where you may have a confining layer. All those things are critical as part of your design, and you get that through the high-resolution characterization, and graphics that come out that look like this.
And then plan view of our data also. Here’s a membrane interface probe data that gives us a sense on a site plan layout of some of the target areas, that the real footprint that we have to pay attention to, the area that we have to focus in on and treat. So I think it’s important in the design process, that you have a lot of different views, be it three dimensional, be it stratigraphy, be it site plan views like this, I think all of it is good. And all of it gives you a spatial representation, and a way to look at the site that’s just gonna help you make the design better.
And lastly, we’ll talk about the execution phase of a project. And this is critical, this is where the rubber meets the road, right, folks? It’s where you’ve done all your homework upfront to make a technology selection or selection of technologies, and then you’ve gone through all that trouble of spending time on the details to get the right design in place. Well, now you got to go out in the field, and you have to make it work. So what are some of the questions that a checklist might have that you need to pay attention to?
So let’s start with this. How about, “Is my injection subcontractor up to speed on the project? I mean, have they been in on the process?” Or are you gonna surprise them with the design, or are you gonna surprise them with what’s gonna happen out in the in the field? I like to hire contractors that know the area, that have injected the chemistry before, that know what to expect. I think that’s very critical. I like to hire Regenesis to inject their own products for just that reason. Who should know their products better than they do? Makes sense to me.
How’s a site access? Do you have one entrance in, one entrance out? What about accessing a neighboring property? Are the proper agreements in place that give you access? What’s the procedure to getting on to that neighbor’s property? All those things are really critical. That’s a really hard thing to find out after the fact when you’re out in the field with a bunch of people on site ready to work. And that issue has not been clarified.
How about permits? Injection permits, are they, in your respective state or are they issued by the state itself, or are they issued by the health department, or are they issued by EPA? What about discharge permits? How about air permits? How about those other unusual permits out there that can sneak up on you? How about things like, in Northern California, I’ve often experienced a borehole permit, where your borehole is actually inspected, and the way that you close that borehole is inspected by a county inspector? And that’s something that exists there that I don’t see in too many other places. How about in the city of Chicago, when I wanna cross the city sidewalk with a heavy piece of equipment, I have to get a sidewalk permit in order to do that? Those are those things that you wanna find out at this execution stage before you’re on site.
How about your health and safety plan? Did you just pull one off your company’s website and plug it in, and say, “Well, this is good?” without really thinking about the specific issues on the site, really thinking about the chemicals that are there, the types of chemistry that you’re now gonna put in the ground? I really think you gotta take that time and develop that specificity. And you have to get a health and safety plan from your subcontractor as well, or at least a Job Safety Analysis, a JSA, so that you have, sort of, their plan, their thinking, their way of doing things, their way of managing safety. All those things are important.
Ask yourself, “Have I visited the site? Have I at least looked at a photo? Have I gone to Google Earth and looked and see what my site looks like? And am I prepared to take more photos to document other things that occur on site?” I think picture says a thousand words, right? And I think the more site photos you have, particularly at this execution stage, the more important they become down the road.
Other questions you might ask yourself. “Does my site have ground cover or not?” So what does that mean? Will your site be susceptible to infiltration from rainwater or runoff from some adjacent property? If it is covered, what’s it covered with? Asphalt? Concrete? Grass? You know, what exists out there? What’s the integrity of that cover? Do you have a major sinkhole in the middle of your site? Do you have asphalt that’s 10 years old, that has incredible number of cracks in it? All those things are critical pieces of information.
And how about infrastructure? You know, boy, it’s awful costly if you hit a fiber optic line. So you need to know certainly what’s in the subsurface at your site. How are you gonna find that out? Are you gonna look at as-built drawings, you’re gonna look at just facility drawings that exist, you’re gonna work with utility locators. You’re gonna probably do some aironizing, you’re gonna do perhaps some hand clearing, and you’re gonna perhaps use ground penetrating radar to identify structures. Maybe several, or all of those in combination.
What does your site traffic look like? People and vehicles. If you’re working at a fast food restaurant, and you’re working in the middle of the day, it’s the lunch hour, and there’s scores of people that are coming by, well, you’re gonna wanna have keen attention to your activities, and the number of people that are around you under that scenario. Then, of course, you’re gonna have to think about vehicles. On my gas station site, I talked about earlier, that meant cars. That also meant the fuel tanker that comes in. Your site, it might be delivery trucks, or other types of tractor trailers that come in. It could be forklifts that buzz back and forth, it could be some light rail, short line rail that comes in, that drops off supplies once a day. All those things are critical pieces of information that may affect how you execute on the site.
And then, how about storm source? It’s a really hard lesson to learn when you suddenly have material you’re injecting in the ground, that emerges to the surface, flows down slope, and winds up in your storm sewer, and then goes off to who knows where. And, you know, what happens if your regulator is on site that day? That’s probably not a surprise anybody wants. So knowing that that storm surge exists, and how that’s gonna be managed in the event that there is fluid that surfaces, that daylights, that’s gonna find its way to that sewer.
And then, how about vegetation? How about setting a proper expectation right from the start on a project? If there are trees, and there are bushes, or there are plantings in very close proximity to your treatment area, and there is a decent likelihood that you will daylight inject aid. Then you will have to set that expectation that there will be some loss of that vegetation. I’ve seen miraculous scenarios where fluid has daylighted in a planter, or to an exotic tree, and it’s miraculously survived. But I would say that that’s the exception rather than the rules. I think you have to set that expectation in your execution, that if there is sensitive vegetation in proximity to your treatment area, it’s probably not gonna survive.
And what else do you notice about adjacent properties? That’s a critical piece of information as well.
As you get into injection specifics, you certainly wanna understand your number of injection points, how many injection events are you gonna have on a site. If it’s a bioremediation site, you know, it’s probably two or three, a chemical oxidation site, probably two, or three, or four, depends on your site, and the amount of mass that’s present.
You’re certainly gonna wanna understand your injection interval. Again, you wanna use chemical in an optimal way as opposed to inefficiently.
You’re gonna wanna understand your technique, especially if your direct pushing. Is bottom up or top down, your better way to go? And that’s determined by consultation with your own experience, Regenesis, your direct push contractor. All those people can weigh in and make that decision.
And then your volume you will inject. Do you wanna have more points less volume? Do you want less points more volume? And there’s some critical decisions that have to be made there.
Then, of course, spacing. You know, are you gonna get crazy, and go 50 feet apart with points? I think not. Under most scenarios, am I gonna be more like eight to 10 feet apart, 15 feet apart? Well, that’s seemingly more like it on most sites.
And then, of course, at this juncture again, you’re gonna wanna try to anticipate the daylighting potential, right? Because daylighting inject aid can come up at all sorts of locations, and quite a distance from where you’re injecting. So that’s something critical to pay attention to.
Then when you’re all done injecting, whether it’s ORCA, or it’s RegeneOx, or it’s PersulfOx, or it’s PlumeStop, you’re gonna want an injection report. And if it’s RRS, I know you’ll get one. If it’s several other contractors that exist out there, they provide them, some don’t, then I would certainly ask them to provide it to you because you wanna know what was the pressures that were needed for breakthrough and for sustained injection? How about the gallons per minute? How about the flow rates? How about the intervals that you’re looking at? How about any particular notes that might cite an unusual circumstance that was experienced during the injection process?
All right. I’m in the homestretch here. Hopefully you’re all with me yet. And I said that I wanted to address safety here, and this is critical. This octagon is a great way to think of safety as you go forward on an in-situ remediation project. We’re gonna skip biological and radiation today, because there are things that, you know, the vast number of you don’t deal with on a regular basis, if ever. But chemical, motion pressure, heat and cold, gravity, electrical…I just wanna point out certain things that you may wanna pay attention to, under each of those categories that are gonna improve your project and improve your ability to work safe.
From a chemical consideration, whenever you’ve got chemistry out there that can cause burns, that can affect your eyes, that can cause issues with inhalation, you wanna be especially cognizant as to what that comes in contact with. You don’t read the safety data sheet. You know, we all have them on sites. We all have them when we have our tailgate safety meetings. How about we read them and start off by respecting the chemical, respect the chemistry? Because even the most benign thing can create a problem if it’s disrespected. You can make a lovely vegetable oil, or emulsion product type solution, and have that surface all over your side, and have a serious slip trip hazard. So, even things as benign as that can cause a problem. So certainly, when you’re working with things like oxidizers, you have to respect the chemistry.
Transportation. You know, ISCO chemicals are regulated under the DOT. They have to be properly placarded. I’m sure most of you are not in the business of hauling chemicals, but some of you are, and certainly the chemicals have to be hauled by someone that has the proper HAZMAT training, that understands the labeling and marking associated with those chemicals. You know, we’re not talking about hydrogen peroxide today, but should that chemistry be on your site, that ups the ante quite a bit, because then you have oxidizer and secondary hazard corrosive that can be really, really critical. So, you know, how you transport chemistry to your site is something you need to be aware of. If Regenesis is doing it for you, hey, all the better, it shows up on your site. But you may have other means by which that chemical is being shipped to your site.
Handling an application. How do you get hurt on a site? You get hurt when the wind blows and reactive dry chemistry winds up in your face, or winds up in your hands, or you breathe it in. You get hurt when something splashes on you. Why? Because you let your guard down for a minute, and you dropped your safety glasses, and the next thing you know, some solution is in your eyes, it’s on your face, got on your hands and then you touched your face. So, dry goods and splashing are two ways in which you get hurt on sites. So start off with at least minimal PPE, a Tyvek, maybe you’ve got to graduate to something more hardy in terms of coveralls, protective boots, gloves, usually little latex gloves are not good, not necessarily your best choice, goggles, and safety glasses. If you’re really gonna be that person doing the mixing or hovering over a mixing tank for a remediation product that’s being mixed, you’re gonna wanna face shield on. It’s not sufficient to just have safety glasses and goggles.
And probably one of the biggest things that’s omitted out of sight and, it’s OSHA mandated, OSHA required, you need to have an eyewash station, preferably one that has a shower with it. Little squirt bottles of water, or the garden hose running from the service station is not sufficient. You may have used that in the past, and that may have been, you know, just gone along swimmingly for you, but really, you need to have an eyewash station. And I know, if you work with our RRS, that type of equipment will be present on the site.
And then you need to have that particulate respirator protection should you get into dry goods, and scenarios where that may dust.
Storage. I will call out a couple of things here. One of the biggest omissions on sites where we do in-situ remediation, particularly when we have oxidizers present, is a failure to notify the local fire department. You think that’s not a big deal, well, it can be. There are places around the country where the fire department actually issues a permit for your ability to store an oxidant on site. It’s not too common, but it does exist. Many fire departments will just simply thank you that you’ve notified them, you have an oxidizer on site. And other fire departments will really wanna see what your plan is for storing an oxidizer, for what sort of period of time will it be stored, and they’re gonna wanna know what precautions you’re gonna take should that oxidizer spill.
On the most extreme cases, fire departments gonna insist that you store your your oxidizer chemicals, things like PersulfOx, RegenOx, and they have you store them in a conex box, or put them behind a fence, and tarp them. So all those things are possibilities, so don’t forget about the local fire department.
And then, you know, if you do have to store chemicals on site, make sure it’s in a proper container. Bad things happen if you take PersulfOx and you put it into a steel drum, and you let it sit there in the baking sun. That’s…You don’t wanna see that result, so you wanna use a poly drum. So you wanna take those types of things into consideration.
Spills and releases. We touched on that earlier. Daylighting or surfacing is a fact of life on every in-situ remediation site. It was a fact of life on the Seal Beach site that I talked about at the beginning of this webinar, and it’s probably a fact of life on your site. So whatever you can do in terms of booms and other sorbents, nonorganic sorbents that can protect the flow of that material from finding its way to some low spot or to a drain, that’s very important. You can put drain covers down. There’s a variety of things you can do to manage that daylighting, especially paying attention to your injection, and not getting crazy because it’s 4:00 o’clock on a Friday, and you wanna get to the bar early. You don’t wanna up the rate of injection just because you feel like you need to speed it up. You know, let the injection run its course, and let pressure and flow be at a manageable rate.
We talked about disposal in a proper drum. I know in a lot of sites, you know, if you’re injecting a large enough volume of fluid, you can have a vac truck on hand that can suck up any kind of spills and smaller applications, perhaps a shop vac scenario, where you can suck up that fluid before it gets too far. Under certain scenarios, you may be able to put that back in the mix tank and reuse it. I don’t recommend you try to neutralize anything on site. If you do happen to have material that has to be disposed of, I think you just, you know, get it secured, and get it shipped off properly, unless you have somebody that’s highly trained in that type of management, and that the waste is well characterized.
And I think some of this can be averted in the beginning by simply calculating how much you’re gonna need, and how much throughput you can do within a single day. You know, not going crazy about how many batches of inject aid that you mix.
Pressure. We all know about that. You may want to set a guideline for your sites. Maybe a sustained pressure no more than 100 psi, or maybe you want it higher than that. That may be company by company specific. You wanna test your piping and your delivery systems that are injecting remediation chemicals, and make sure they’re operating at 150% of their operating pressure. You wanna check for leaks. You wanna use whip checks to hold hoses down. If a fluid is passing through a hose, that hose moves around.
Motion. We got lots of things in play at sites. We’ve got people moving, we’ve got hoses moving, we’ve got cords moving, we’ve got open holes that a person could step in, maybe we’re taking covers off of wells. We’ve got vehicles that are moving around. So from a motion standpoint, those are things you need to pay attention to. And we have some examples there in the slide photos.
Gravity. Well, at sites we don’t pressure inject but we gravity feed. That may entail having tanks lifted up at a particular level to generate more head. That in and of itself can create some risks. You know, we also wanna be sure, you know, when we’re lifting around dry bags or totes, that we’re doing that in a proper manner, and again, paying attention to slips, and trips, and things, as we’re gravity feeding on the site.
Heat. You know, we certainly all worked on hot days, and we know that heat stress can manifest itself, so we wanna be cognizant to that, perhaps even adjust our PPE under certain circumstances. And we wanna be cognizant of things that have exhaust, or things that get hot during the course of an injection event, engines, compressors. And under certain scenarios, the ISCO chemistry itself. You wanna be cognizant, you know, potentially of a reaction, particularly in warmer weather that could up the temperature of the solution that you’re working with. If you work within proper ratios that have been specified, most of the time that’s not gonna become an issue but it can be.
And then, lastly, electrical. You know, there’s certainly… you know, we have various devices that we have on site, that run by electricity, so we need to be cognizant of those, perhaps adopt a lock-out / tag-out procedure. Also, be cognizant of underground electrical. That’s certainly one of the ones you wanna avoid at all costs. Keep an eye…A sense of everything that’s energized.
And then just to wrap up here, I want to make a couple of comments on the monitoring that exists on a site. Field monitor, during the course of injection, there’s nothing worse than doing an injection event, and not having the capacity to monitor it. I think you wanna be prepared for that going in, and you wanna collect all the field data that you can, and all the observations that you can while you’re monitoring.
And then set a period of time when you’re gonna collect samples. Probably no sooner than 14 days, but some sites, 14 days is a good time to get out and actually go out and collect the sample out of site, or 30 days, or 45 to 60 days. Those are ideal timeframes to see chemistry in action. And if you’re not monitoring an injection soon enough after injection event, you’re gonna miss something.
And then, lastly, just some additional thoughts on post injection monitoring. Most of your action takes place in the first two months post injection. Certainly, true for oxidants, can be very, very critical for bioremediation agents. That’s a very sweet spot of which to see progress, and maybe get a sense of how much progress you’re gonna make down the road.
And then my last point, if in fact you do chemical oxidation on a site, keep in mind that the chemical oxidant may have found its way in a very connected manner to your monitoring well. And when you go out to sample at some specific period, the pH of that well maybe very acidic or very alkaline, so check that before you even pull your sample, and be prepared to have the proper PPE in place.
Hooray. Wrap up. I think we’ll have a little time for questions. I’ll certainly get back to you with any other answers. But I guess the message today is, as you employ a project checklist on sites to better improve performance and safety, make sure data collection is a part of it. Make sure you’re ultra-prepared. Make sure you’re asking yourself and your project team the hard questions, paying attention to the details. And make sure when you get out on site, you have a keen sense of awareness, you’re really looking at the things around you. Be open minded to various options, and that will yield better results for you, and help you save money.
So, with that, I’ll take questions in whatever time we have. And I wanna acknowledge just my colleagues at Antea Group that were instrumental in contributing to the aspects of this presentation. Have fun developing your checklist. And hope it leads to safe and successful projects. Dane, back to you.
Dane: All right. Great. Thank you so much, Jack.
That concludes the formal section of our presentation. So at this point we’d like to shift into the question and answer portion. We do have a couple of minutes for some questions.
Before we do this, just a couple of reminders. First, you’ll receive a follow up e-mail with a brief survey. We really do appreciate your feedback. So, please take a minute to let us know how we did. Also, after the webinar, you will receive a link to the recording as soon as it is available.
All right. So let’s circle back to the questions. If we’re not able to get to your questions today, we’ll make an effort to follow up with you after the webinar. All right. So, first question here, Jack, is, “What’s the minimal geochem data I can collect and still have something reasonable on which to make decisions?”
Jack: Well, I would say that, if you’re just starting out, perhaps you’re a little low on budget, you know, at least collect nitrate, total and dissolved iron, sulfate, methane, and, you know, if you still have a little money left, carbon dioxide, and or alkalinity. I think that’s a good start for a petroleum site. For chlorinated site, I’d probably lump on to that total organic carbon and perhaps chloride, just as a starter, and you can build on it from there.
Dane: Okay. Great. And we’re also getting questions, requests for copies of your slides, and your select design execute project checklist. Can we share that with the folks who would like a copy?
Jack: Yeah. We’ll be able to make a PDF of the slides available, and I will provide a starter Excel checklist, with, sort of, some seed categories, and labor categories, and people can build their own from there.
Dane: Okay. Great. We maybe have time for one last question here. A good question that came in is, “Can you give an example of how an injection subcontractor did not understand the local soil and will add up the products being injected, and how that proved to be a problem on the site?” So this person is asking…this person focuses more on when it’s a problem. And maybe talk about the difference between when the subcontractor understands the local soil and the products, versus when they don’t, and how that’s important.
Jack: Yeah. I think that’s very important. Well, I’ve seen that in a couple different ways. First of all, I’ve seen contractors that perhaps were not as accustomed to working would show up on site, with the wrong direct push equipments, something that’s not gonna be robust enough for the geology that we’re working under, and subsequently waste a whole lot of time trying to push through and get fluid into the subsurface. So that’s one way it can be a problem.
The other one is a lack of understanding of the chemistry, and the real ways to finesse the pressure, and the flows, too much is too much. And too much of a hurry usually results in bad results, a bad outcome on sites. So I think that’s another way that I’ve seen that manifest itself, where you’ve got a contractor who doesn’t necessarily know the chemistry, and starts to go too fast, and the next thing you know, you’ve got product pushed into monitoring wells, or daylighting at 10 different locations, and really creating a problem.
Dane: Okay. Great. Thank you so much, Jack. We do have more questions, but we do have some more questions but we’re unfortunately out of time, so that’s gonna be the end of our chat questions.
To those of you in the audience, if we did not get to your question, someone will make an effort to follow up with you.
If you need immediate assistance with a remediation solution from Regenesis, please visit regenesis.com to find your local technical representative, and they will be happy to speak with you.
Thanks again to our presenter, Mr. Jack Sheldon. And thanks to everyone who could join us. Have a great day.