WASHINGTON — Hydraulic fracturing to drill for oil and natural gas has not caused widespread harm to drinking water in the United States, the Environmental Protection Agency said Thursday.
But a draft report issued by the agency found several specific instances where poorly constructed drilling wells and improper wastewater management affected drinking water resources. It said the number of cases was small, however, compared with the large number of wells that use hydraulic fracturing, better known as fracking.
The controversial drilling technique could affect drinking water if safeguards are not maintained, the report said.
, from acquiring the water to mixing chemicals at the well site and injecting so-called “fracking fluids” into wells, to collection of wastewater, wastewater treatment and disposal.
The report identified several vulnerabilities to drinking water resources, including fracking’s effect on drought-stricken areas, inadequately cased or cemented wells resulting in below-ground migration of gases and liquids, inadequately treated wastewater discharged into drinking water resources, and spills of hydraulic fluids and wastewater.
Improved drilling techniques have led to a surge in fracking in recent years that has fueled a nationwide boom in production of oil and natural gas. Fracking involves pumping huge volumes of water, sand and chemicals underground to split open rocks to allow oil and gas to flow.
Improved technology has allowed energy companies to gain access to vast stores of oil and natural gas underneath states, including Colorado, but has raised widespread concerns that it might lead to groundwater contamination and even earthquakes.
Industry groups hailed the EPA study as proof that fracking is safe, while environmental groups seized on the report’s identification of cases where fracking-related activities polluted drinking water.
EPA officials said the report was not intended to prove whether fracking is safe, but instead was aimed at how state regulators, tribes, local communities and industry can best protect drinking water and reduce the risks of fracking.
“It’s not a question of safe or unsafe,” Tom Burke, deputy assistant administrator of the EPA Office of Research and Development, said in a conference call with reporters. The issue for the EPA is “how do we best reduce vulnerabilities so we can best protect our water and water resources?”
