Gas Drilling Companies Hold Data Needed by Researchers to Assess Risk to Water Quality

For years the natural gas drilling industry has decried the lack of data that could prove—or disprove—that drilling can cause drinking water contamination. Only baseline data, they said, could show without a doubt that water was clean before drilling began.

The absence of baseline data was one of the most serious criticisms leveled at a group of Duke researchers last week when they published the first peer-reviewed study linking drilling to methane contamination in water supplies.

That study—which found that methane concentrations in drinking water increased dramatically with proximity to gas wells—contained “no baseline information whatsoever,” wrote Chris Tucker, a spokesman for the industry group Energy in Depth, in a statement debunking the study.

Now it turns out that some of that data does exist. It just wasn’t available to the Duke researchers, or to the public.

Ever since high-profile water contamination cases were linked to drilling in Dimock, Pa. in late 2008, drilling companies themselves have been diligently collecting water samples from private wells before they drill, according to several industry consultants who have been working with the data. While Pennsylvania regulations now suggest pre-testing water wells within 1,000 feet of a planned gas well, companies including Chesapeake Energy, Shell and Atlas have been compiling samples from a much larger radius – up to 4,000 feet from every well. The result is one of the largest collections of pre-drilling water samples in the country.

“The industry is sitting on hundreds of thousands of pre and post drilling data sets,” said Robert Jackson, one of the Duke scientists who authored the study, published May 9 in the Proceedings of the National Academy of Sciences. Jackson relied on 68 samples for his study. “I asked them for the data and they wouldn’t share it.”

The water tests could help settle the contentious debate over the environmental risks of drilling, particularly the invasive part of the process called hydraulic fracturing [1], where millions of gallons of toxic chemicals and water are pumped underground to fracture rock. Residents from Wyoming to Pennsylvania fear that the chemicals will seep into aquifers and pollute water supplies, and in some cases they complain it already has. But the lack of scientific research on the issue – including a dearth of baseline water samples – has hindered efforts by government and regulators to understand the risks.

The industry has two reasons to collect the data: To get to the bottom of water contamination problems, and to protect itself when people complain that drilling harmed their drinking water.

“Unless you have the baseline before the analysis you can argue until the sky turns green,” said Anthony Gorody, a geochemist who often works for the energy industry. “The only real way to address this without anybody bitching and moaning is by doing this before and after.”

Chesapeake Energy alone has tested thousands of private water supplies in the Marcellus Shale, and the company says its findings demonstrate that much of the water was contaminated before drilling began.

“Water quality testing… has shown numerous issues with local groundwater,” wrote the company’s spokesman, Jim Gipson, in an email to ProPublica. “One out of four water sources have detectable levels of methane present… and about one in four fail one or more EPA drinking water standards.”

Gipson declined to elaborate on the findings or share Chesapeake’s test results, making it difficult to verify whether the companies had, indeed, found the water was contaminated before drilling began. But he did note that Pennsylvania does not regulate water quality in private wells and that water sampling is typically not done by homeowners.