Tank Talk - Alaska's Bulk Fuel Podcast
Tank Talk - Alaska's Bulk Fuel Podcast is a podcast that delves into various aspects of environmental management and regulations, mainly focusing on bulk fuel storage, fish processing, and utility facilities across the Pacific Northwest. Hosted by industry expert Shannon Oelkers, Tank Talk features discussions with industry leaders to answer questions commonly asked by terminal managers. Episodes cover various topics involving State and Federal regulations, tank inspections and permits, and industry vendors. Tune in to navigate the complexities of rules and operations, offering insights and information to listeners involved or interested in environmental compliance and best practices within specialized industries.
Tank Talk - Alaska's Bulk Fuel Podcast
Secondary Containment Area Drainage
Are you ready to become an expert in managing secondary containment areas? Buckle up as Shannon guides you through the process of clean water de-watering in containment zones. We tackle the nitty-gritty, from inspecting water for oil or sheen before discharge to laying out the standard procedures to initiate and halt containment drainage. We explain what to do when sheen or fuel is spotted and delve into the two types of discharge processes - manual and automatic.
The second part of our discussion centers around the significance of secondary containment area drainage. We dissect various permits and regulations that dictate adequate containment, drainage, monitoring, record-keeping, and maintenance procedures. Whether you're a facility manager, an environmental consultant, or just curious about containment area management, we have practical advice and crucial information. Tune in, and let's learn together!
This podcast is for informational purposes only and should not be considered legal or regulatory advice. We are not responsible for any losses, damages, or liabilities that may occur from using this podcast. This podcast is not intended to replace professional regulatory or legal advice, and the views expressed in this podcast may not be those of the host, which would be me or Integrity Environmental. Thank you very much for listening. We would be happy to provide professional regulatory advice as part of our consulting services if you need professional regulatory advice.
intro/outro created with GarageBand
Welcome back to Tank Talk. It's lovely to have you here today. Shannon, How are you doing?
Shannon:I'm doing really great Amanda.
Amanda:Good Well, today is a listener request. It came through LinkedIn from a listener, Sam, who said May I suggest dewatering of clean water from secondary containment areas as a future topic? I love your short, concise talks about tank farms.
Shannon:Well, thank you, Sam, and that is an excellent topic suggestion.
Amanda:The secondary containment with design holds water and that water has to be removed regularly. Is there a standard process for this?
Shannon:Yes and no. So yes, all secondary containment areas have to remove water and there are standard processes for this that are general. You're supposed to inspect the water for sheen or any other evidence of oil pollution prior to discharge And then, once that check has been accomplished, then you are supposed to dewater and there's some steps to the dewatering. but it's not standard because there are many different kinds of secondary containment area types and dewatering types. Each facility is a little different. The general procedures for starting and stopping containment drainage are the same, but the specifics can vary pretty widely depending on how your containment area is constructed and maintained. Sometimes the way it was originally constructed no longer works and they've got alternative drainage methods now.
Amanda:What happens if you see fuel or a sheen?
Shannon:Well, you panic. No, i'm just kidding. It's usually one of three things. when you see the sheen on the water, You actually have a leak, either from your infrastructure, or sometimes you've got contractors working in your tank yard and there'll be contractor equipment that's leaking.
Shannon:Sometimes it's residual fuel from a fill connection or a fuel transfer, like when you detach the cam lock or the dry brake, you know fuel drips or weeps out of it and that's what you're seeing. And then, lastly, sometimes a pass spill will settle into dirt or sediment that's within the secondary containment and that residual fuel from that pass leak. it'll float up to the top as you're walking through or disturbing that sediment. It can be really difficult to get that kind of stuff out of a tank farm that has a liner with a dirt floor on top of it, for whatever reason. if you've got sheen, that means that you need to stop, investigate, determine the source and remove the source of the sheen and the sheen itself and then treat the water. And I'm going to save water treatment for a future podcast on storm water permitting, because water treatment is changing rapidly as we speak. I want to take the time to address that thoughtfully. So let's just assume that there is no sheen for this discussion today.
Amanda:So we've inspected the water. No sheen or fuel has been observed. What's next?
Shannon:Discharge, my favorite.
Shannon:Every system's unique, so that exact discharge process is something our listeners will need to look up in their SPCC, their ODPCP plan, or sometimes it's in the operations manual, sometimes it's in all three and sometimes they differ, which is super fun.
Shannon:But basically, if you're listening to this, figure out what your discharge procedure is supposed to be from whatever resource you've got internally. And there's basically two types of discharge processes. There's manually, where a human being has to actually turn a pump on, open a valve, do something to initiate the discharge, or an automatic or electrically operated system, and that's one where there's a hydrocarbon sensor. It doesn't sense any hydrocarbons And then, when the SCA level gets to a certain point, it triggers a pump to begin drawing water down and pumping it out as an automatic discharge. I've also seen pretty frequently in rural Alaska that the original valve drainage system is damaged in some way And so there is infrastructure there and it looks like you could drain it with a valve, but instead they've closed that valve and they're actually using a sump pump in the low area to discharge the SCA over the wall of the containment area.
Shannon:And, as a side note, there's an SPCC requirement for manually operated valves on all secondary containment drainage systems In the olden days which was not that long ago 15 years ago and prior there used to be what they called flow through systems, and that would be like in it would be a secondary containment area that discharged directly to an oil water separator And that oil water separator would process the water and would flow out the other end of the oil water separator to a beach or a vegetated swale or something like that. Those flow through systems don't have any brakes on them, though here tare no valves in them. There have been taken off nd so those are no longer allowed under the SPCC requirements. You have to have at least one manually closeable valve in that system.
Amanda:Wait, so a flow-through system isn't allowed anymore.
Shannon:Not under 40 CFR 112. It makes sense. There's got to be a way to close the system if it gets overwhelmed with fuel from a full release, and I think a lot of those older systems assumed it was going to be handling routine maintenance type spills. Right, you know sheen that collects or maybe a few drops of fuel spilled from a transfer. But if you had a full release of like your largest tank volume, it would push out all the water in your oil-water separator and then begin discharging fuel. If there's no way to turn that system off And I just want to make sure before I get a bunch of emails from people that this is different from an automated drawdown system with hydrocarbon sensors and automated closed valves, all the bells and whistles. We're talking about the old-school open drain through with no brakes. There's no way to turn it off. Those are not allowed if you have an SPCC facility. Currently.
Amanda:Okay, so we've inspected, we've started draining. What's next?
Shannon:Everybody's favorite record keeping. Pretty much every permit requires secondary containment drainage to be documented. They all say it a little bit differently, but the basic information that should always be recorded for a containment drainage is whether the presence or absence of sheen or fuel was observed, the start and end time of a discharge and the estimated volume of the discharge. If you have a multi-sector general permit stormwater, you'll have additional monitoring on top of this. Again, maybe a different podcast, but the base is still the same Is there sheen or fuel observed, yes or no, the start and end time of the discharge and the estimated volume.
Amanda:I've seen some secondary containment areas that are really big with really odd shapes. How do you estimate a volume drain from that?
Shannon:It is difficult if your containment area is irregularly shaped. It can be really complicated math And what we suggest is to perform basic flow through calculations instead. For example, if you know your discharge pipe is three inches wide and it has an average flow through rate of 200 gallons a minute and you had water flowing for two hours, which is 120 minutes, you can make a pretty well informed guess that you had about a 24,000 gallon discharge for that day. Same math if you're using a sump pump. You're just going to base it on the pump's output. You know how much the pump can push in an hour. Then that's usually from the manufacturer documentation And then everybody goes.
Shannon:But wait, shannon, that's going to be inaccurate because head pressure changes. Right, the amount of water pushing down is going to slowly get lower and your pressure is going to be lower. So you're going to have differing rates of discharge, and that is true. But what we're, what we're looking at, is an informed estimate or average. We're not. We're not necessarily going for very, very specific, and I'll get to why in a minute. The important part is however you decide to do it, do it consistently, do it the same way every time, no matter who's draining the containment down, and some people do install flow meters on their outfalls Just to account for that inaccuracy. So if you want to be very detailed, go the flow meter route. You'll know exactly what goes through the end of that pipe. However, maintaining those flow meters can be pretty tricky and freeze up conditions. They're very often damaged by spring and fall freeze, though cycles?
Amanda:Why do permits require volume estimates?
Shannon:That's a great question. A lot of older record keeping doesn't include volume estimation. It was just a basic check for sheen and then a discharge event was tracked. But that volume estimation becomes really important.
Shannon:I can be used two ways. One is it alerts you to problems like if you normally have 24,000 gallons a day or more coming out of a section of your tank farm and all of a sudden The weather hasn't changed but it's dropped to five or six thousand gallons in a day. It could be a drought Right like, let's say, just stop raining, which makes sense, but it could also be a hole in your liner a few inches from the bottom and it's only retaining so many inches of stuff. So usually if you're getting pretty consistent flow through numbers or flow through times and the weather hasn't changed, it can kind of be an early warning system for something being wrong with your containment system.
Shannon:The other reason which is why we typically are bringing it to the table is that we're doing compliance verification. So during the compliance process so a state or federal regulator will come to your facility and they'll Determine that they there are some things that they think are not compliant going on. Regulators use estimated volumes to verify. You are monitoring the discharge. But if they find a problem like a leaking tank that impacted containment water and It's been leaking for an unknown time because it wasn't being documented on a daily, the state will often base their fines on the maximum discharge potential per day if there's no actual numbers. So Let's say you're averaging 24,000 gallons a day of discharge, but your tank firm could actually hold a hundred thousand gallons of water based on its structural design. If we don't have actual numbers, the state or the federal government will start with the maximum, assuming that it's full of water, and so that can Really ramp up fines. Trust me in this one. You really want actual numbers to refer back to instead of your maximum Potential as far as containment volumes.
Amanda:Thanks for walking us through the whole secondary containment draining process. I'm sure you have a great list of common problems you've encountered in the field you could share with our listeners.
Shannon:Yeah, we definitely see some pretty consistent common issues. The good news is most of these are easily fixable if you require more work. The biggest one is that we see poor or no record keeping. We often see no volume estimates, and no start or end times. Those are the biggest missing pieces. Pretty much everybody's figured out a way to record a yes or no answer for is sheen observed, but when it comes to when the discharge started and stopped and how big it was, those are pretty frequently missing. We also see people not performing containment drainage enough and you'll see like massive buildups that freeze.
Shannon:I've seen a lot of containment areas where I show up and they've got two thirds of their containment full of ice. It's really hard to drain that down and keep ahead of that, especially during the freeze-up time, which is why they ended up with so much water forming drainage frequently enough. that same scenario that I just mentioned about having a massive secondary containment area and having it be really full of ice. that's also related to having a drainage system that is not engineered for the volume of water that you are collecting. That one inch sump pump you've got trying to augment your three inch drain. it can't keep up with the volume of water that this tank farm is encountering, even if they all run 24 hours a day. Typically when we see big buildups like that, one of the suggestions we work on is do you need an engineered solution to make it easier for your guys to drain this within normal operational hours? Let's see What else. Not removing vegetation or trash Trash blocking drainage lines is really common Pro tips. spray paint can lids are perfect for blocking three and four inch drainage lines.
Shannon:I've pulled quite a few out, let's see. I also see people only draining one location of the containment area, where the sump is, and ignoring other low spots. All tank farms settle over the life of them and those secondary containment areas can end up with low spots that are not where they intended them to be originally. They end up only draining from the one low spot where the drain is supposed to be, but then there's all these other little scattered locations that just hold water all the time and don't ever get drained out.
Shannon:I also see people leaving impacted sands or soils in the containment after a spill. Every time you walk through, it stirs up a sheen. If you have a spill situation, it's really critical to remove as much of those soils as you can to prevent that. This last one is the. I see it all the time. I understand why it occurs, but it is definitely a violation, which is leaving the containment drain open all the times. Leaving the containment drain open at all times. This, folks, this is your last and best defense system and that is disabling it. If you leave it open all the time, because dealing with the water that is collecting is a big pain in the but, if you have a failure of a tank or a pipeline, it's just going to drain right out and you've just disabled that backup system that you have in place.
Amanda:Don't disable it please Container containment area drainage is pretty important for SPCC compliance correct.
Shannon:It is. it is, but it's not just the SPCC. Storm water and wastewater permits heavily involve containment, drainage, and and both the facility response plan and ODPCP. the state of Alaska a C C plan. They all have containment drainage requirements as well for monitoring, record , and and operation maintenance and operation. Dear listener, make sure you know the inspection and drainage process at your facility, make sure your record keeping is adequate, make sure your secondary containment area is free , sheen, and trees and trash And make sure your drainage systems are maintained and easily operated. All of those things are supporting this immense backup system that you do not want to be disabled when the worst or unthinkable can happen.
Amanda:All right, well, thank you so much, Shannon, for diving into secondary containment area drainage with us today.
Shannon:And thank you, Sam, for the excellent suggestion, And if anybody else has a suggestion for a podcast episode, I am happy to receive it. We've gotten some really good ones lately and I'm excited to start recording those. So please give us your suggestions. We appreciate them. Yeah, thanks everybody. Bye.
