Without a thorough understanding of the risks of produced water, it’s hard to motivate managers and maintenance teams to keep pits and ponds secure and well-kept. Yet, a single, large leak of produced water can have long-term environmental effects that come with expensive fines from state and federal environmental agencies. Add up the risk of numerous or long-term leaks and the cost multiples. Produced water has a few specific risks different than other types of wastewater, like sewage, that makes it similar to other challenging materials.
Hydrocarbons and Oil
When hydrocarbons and oil residues mixed into produced water get into the water and soil, they cause long-term damage that is hard to remediate. Unlike salt and short-lived chemical compounds, oil residues can harm saltwater just as much as freshwater. Discharging produced water into the ocean can interfere with marine life cycles, even if the salinity wouldn’t be a problem with this kind of release. Oil residues tend to float on the surface of the water after discharge, bringing it into contact with a lot of plant and animal life. Keeping it secured in a covered pit, until it can be discharged or treated, is the best way to keep oil from escaping into the environment.
Dissolved Solids
Like most other mining and drilling byproducts, produced water from fracturing is high in dissolved solids. The sand and sludge in this particular type of waste must be removed periodically to leave space for the actual water, but it’s hard on the liner to both store and remove this debris. If the produced water is released into the groundwater or a nearby surface water supply, the solids settle into the river or lake and can have long-term effects. Sedimentation from these dissolved solids can eventually fill up drainage channels, ponds, and release areas to back up the system. Make sure to use settling techniques to manage dissolved solids before any water is discharged.
High Salinity
Produced water is particularly likely to have a high salinity because natural gas often accumulates in salt caverns formed deep underground. The water that also collects in these caverns, along with the freshly added fracturing fluid, picks up a lot of salt along the way. Many produced water mixtures count as concentrated brines due to the extreme salinity. Salt is a problem for both soil and water. In soil, it lingers for years or even permanently while suppressing plant growth. In the water, it kills off sensitive freshwater life. Salinity isn’t a problem when produced water is released directly into a large body of saltwater like an ocean, but this water often has other components that could damage marine life.
Toxic or Reactive Compounds
Since any number of dissolved minerals and heavy metals can be mixed into fracking wastewater, it’s hard to predict what reactive compounds will form in the storage pits and ponds. In many cases, the compounds that first emerge from the fracturing well will combine, break down and then transform into other chemicals entirely. If the various minerals and compounds escape into the surrounding soil and water, still more unexpected reactions could occur. Aquatic life, like fish and plankton, are particularly sensitive to chemicals like dioxins and sulfur, but even plant life will react negatively to high enough levels of minerals and heavy metals.
Varying Composition
Each well or hydraulic fracturing operation produces a different mixture of chemicals, salt, dissolved solids, and other hazards. It’s not always easy to predict what will come out of a particular operation before it begins since preliminary tests will only show a small sample of the water contained in the deposit. Using a liner with a widespread set of resistances to chemical damage is essential. Pits must be designed to handle both the cleanest and dirtiest potential produced water.
Air Emissions
Produced water transfer and storage facilities can cause more than just soil and water pollution. There’s also the opportunity for air emissions anywhere the wastewater has a chance to evaporate or turn into a spray. Volatile organic compounds (VOCs) that contribute to greenhouse and acid rain issues are released by evaporation produced water. Flashing off the evaporation can reduce this effect, but only when it’s operated at the correct temperatures and with scrubbers to control emissions. As much care should be taken with air emissions from produced water as with water leaks.
Underground Injection Issues
Injecting the produced water deep underground is one of the most secure permanent methods to dispose of the waste. Unfortunately, this kind of disposal still isn’t without its drawbacks either. The water injected deep into a well or cavern can still escape the storage area and infiltrate nearby water tables and underground supplies. Irrigation and drinking water supplies can become contaminated by the process water when it’s injected without any treatment. Sealing the caverns before injecting the produced water or sticking with above-ground treatment ponds can prevent these problems.
There’s no reason to let the risks of produced water leaks prevent the on-site storage of a facility’s waste. Proper design can control any amount of produced water, even if it’s high in hydrocarbons and reactive to many geomembrane materials. Simply make sure to choose a liner that can handle the challenges of containing oil and gas byproducts. You’ll find all the materials you need here at BTL Liners.
