In the oil and gas industry, brine ponds are used to contain flowback water from fracking. Flowback water is water that is used during the hydro-fracturing process to fracture the earth and release oil and gas deposits. Fracking wells can use up to 5 million gallons of water, which has a very high salt content. During the process, some of this water flows back up and out of the well—hence the term “flowback” water—where it is collected in brine ponds for storage.
This type of containment requires extremely durable pond liners and extra precautions. Flowback water is typically highly contaminated with hazardous chemicals that cannot be allowed to leak into local aquifers, plus the brine is far saltier than seawater. In many areas, there are bans on releasing flowback water into sewage or water treatment facilities, so brine ponds are a way for mining companies to contain, store and reuse flowback water.
