Concerning or referring to fracking fluids that are brought back to the surface from the drilled holes in the shale or layers of stone: "At some point, flowback fluids are no longer clean enough to be reused, and must be thrown away and the proper disposal of such flowback fluids is very important for the protection of both surface water and groundwater."

"Although disposal of flowback fluids in injection wells is currently the most effective means of safely isolating these fluids from the near-surface environment, the required specific geological conditions that are required for such wells do not exist in all areas."

"Depending on the geographical location, there may be other methods of handling flowback fluids; such as, treatment and discharge."

"Advances in flowback fluid treatment technology offer the promise of using flowback fluid for other purposes, rather than simply disposing of it; for example, use of filtration, reverse osmosis, decomposition in constructed wetlands, ion exchange, and other technologies may eventually result in the widespread practice of using flowback fluids for such things as managed irrigation and land application."

"One procedure in use today is the recycling of flowback fluids so they can be reused in other hydraulic fracturing jobs, which is one way to save water."

Fracking fluids that are brought back to the surface: "These returning fracking fluids or flowbacks can carry many naturally occurring elements that pose hazards, including heavy metals; such as, barium, and radioactive cesium."

"Some operators put returned flowbacks (fracking fluids) in lagoons or pits which are nothing more than excavated holes in the ground and such flowbacks can leach out of the bottom of these pits and contaminate underlying groundwater."

"To prevent such contamination by flowbacks, operators are beginning to utilize closed loop systems, which store and transport flowbacks within a series of pipes and into above-ground tanks."