By Bill Hughes, WV Community Liaison
We were recently asked if there is a reliable way to determine what constituents are being housed in certain types of oil and gas storage containers. While there is not typically a simple and straightforward response to questions like this, some times we can provide educated guesses based on a few photos, placards, or a trip to the site.
One way to become better informed is to follow the trucks. The origins of the trucks will determine whether the current stage in the extraction process is drilling or fracturing (the containers cannot be for both unless they are delivering fresh water). Combine that with good side-view photos of the trucks will tell you if they are heavier going into the site or heavier leaving. Look for the clearance between the rear tires and the frame. Tanker trucks can typically carry 4000 gallons or 100 barrels.
For a quick guide to oil and gas storage containers, see the “quiz” we have compiled below:
Storage Container Quiz
1. What is in this yellow tank?
Answer: This yellow 500-barrel wheelie storage tank in photos 1 and 2 is a portable storage tank, identified in the placard in photo 2 as having held oil base drill mud at one time. Drillers prefer to keep certain tanks identified for specific purposes if at all possible. This is especially true if they have paid extra to get a tank “certified clean” to use for fresh water storage. A certified clean tank does not mean that the water is potable (drinkable).
Other storage containers that hold fresh water are shown below:
2. What is this truck transporting?
Answer: This type of truck is normally used to haul solid waste – such as drill cuttings going to a landfill. Some trucks, however do not make it the whole way to the landfill before losing some of their contents as shown below.
3. How about these yellow tanks?
Answer: The above storage containers are 500-barrel liquid storage tanks, also called “frac” tanks.
In photo 2 you can see that at least one tank is connected to others on either side of it. In this case you need to look at the overall operation to see what process is occurring nearby — or what had just finished — to determine what might be in the container presently.
The name plate on photo 1 says “drill mud,” which means that at one time that container might have held exactly that. Now, however, that container would likely have very little to do with drilling waste or drill cuttings. The “GP” and the number on the sign refers to Great Plains and the tank’s number. These type of tanks do not have official placards on them for the purposes of DOT labeling since they are never moved with any significant liquid in them.
4: What about these miscellaneous tanks?
Answer: There is no way to know – unless you have been closely following the process in your neighborhood and know the current stage of the well pad’s drilling process. Tank farms are usually just for storage unless there is some type of filtering and processing equipment on site. The drilling crews (for either horizontal or vertical wells) do not mix their fluids with the fracturing crew. That does not mean that one tank farm could not store a selection of flowback brine—or produced water, or drilling fluids. They would be stored in separate tanks or tank groups that are connected together – usually with flex hoses.
Since I am in the area often, I know that the tanks in photos 1 and 2 were storing fresh water. Both sets were associated with a nearby hydraulic fracturing operation, which has very little to do with the drilling process. You will never see big groups of tanks like this on a well pad that is currently being drilled.
The third set of tanks with no connections on an in-production well pad are probably just empty and storing air – but not fresh air. These tanks are just sitting there, waiting for their next assignment – storage only, not in use. Notice that there are no connecting pipes like in photo 2. The tanks in photo 3 could have held any of the following: fresh water, flowback, brine, mixed fracturing fluids, or condensate. Only the operator would know for certain.