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EPA's Study of Hydraulic Fracturing and Its Potential Impact on Drinking Water Resources

Review of Well Operator Files

In 2010, EPA conducted a survey of onshore oil and gas production wells hydraulically fractured by nine oil and gas service companies in 2009 and 2010. Drilling, construction, and completion information for a statistically representative sample of hydraulically fractured oil and gas production wells was collected and summarized in two separate reports. Results of the survey are statistically representative of an estimated 23,200 wells hydraulically fractured by the nine service companies.

The first report describes the relationship of well design and construction characteristics to drinking water resources and the number and relative location of well construction barriers (e.g., casing and cement) that can block pathways for potential subsurface fluid movement

The second report provides insights into the potential for hydraulic fracturing fluids or subsurface fluids affected by hydraulic fracturing to move to underground drinking water resources during hydraulic fracturing.

This work was done as part of EPA's Study of the Potential Impacts of Hydraulic Fracturing for Oil and Gas on Drinking Water Resources.