The current debate over the impact of hydraulic fracturing (hydrofracking) on water supplies got stirred up last Wednesday by decades-old documents touted by proponents and critics of the process.

The Environmental Working Group (EWG) and EarthJustice uncovered a 1987 U.S. Environmental Protection Agency (EPA) report that connected the contamination of a private water well in West Virginia to a natural gas well drilled and hydrofracked nearby. But Energy in Depth (EID) found a document from state regulators at the time blaming the contamination on complex regional geology.

The debate concerns drilling reports from the 1980s and 1940s.

After Kaiser Gas Co. drilled and hydrofracked a 4,500-foot in well Jackson County, WV, in 1982, fracturing fluids from the well traveled through cracks in the shale formation into older wellbores drilled in 1941, according to the EWG report. The fluids then seeped into 500-foot deep aquifers through gaps and cracks in the casings of those older wells and contaminated a private water well.

The West Virginia Department of Public Health’s Environmental Health Services Lab tested the water supply at the time and found gelatinous material similar to those used by drillers, as well as hydrocarbons, but it did not conclude that hydrofracking caused the problem. While EWG acknowledged that “it is possible that another stage of the drilling process caused the problem,” it said evidence from its own yearlong investigation pointed to hydrofracking as the culprit, in part because the gel found in the water supply “is consistent with contamination from hydraulic fracturing fluid.”

But EID cited a 1987 letter from a West Virginia Department of Energy official that traced the contamination to unexpected aspects of the shallower Pittsburg sand in the region.

“At the time the permit was issued concerning this well, the Division [of Oil and Gas] had no knowledge that the Pittsburg sand was a fresh water source,” Then-Deputy Director of Inspection and Enforcement Ted Streit wrote. “This is because in certain areas oil and gas is produced from the Pittsburg.” The department quickly drafted new well construction standards to address the problem.

While the natural gas industry claims that there has never been a documented instance of hydrofracking contaminating water supplies, critics point to anecdotal cases where landowners report problems shortly after hydrofracking begins nearby (see NGI, June 13; May 16; March 23).

The industry in turn cites studies attributing many of those cases to the idiosyncrasies of regional geology, natural migration or poor well construction. State oil and gas associations made similar critiques in the 1987 West Virginia case, according to the EWG report, saying, “EPA is incorrect in its statement that the fracturing of a well can result in contamination of nearby water wells…Such a statement is completely without support in the study. In fact, we know of no case where this has occurred given proper casing. The zones which are fractured are several thousand feet below the deepest fresh water zones making contamination of the fresh water zones extremely unlikely.”

EWG, though, cited anonymous EPA employees who said the agency did not include other examples of hydrofracking contaminating water wells in the report because “the details were sealed under confidential legal settlements reached between affected property owners and energy companies.”

The EWG also said the EPA did not include the case in its 2004 report on hydrofracking in coalbed methane wells — a report that originally planned to include shale wells but narrowed the scope because “EPA has not heard concerns from citizens regarding any other type of hydraulic fracturing.”

The EPA is drafting a report on hydrofracking and water quality (see NGI, May 9).

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