EPA has selected case studies that it believes will provide the most useful information about the potential impacts of hydraulic fracturing on drinking water resources under a variety of circumstances.
EPA currently is working closely with industry partners to identify locations and develop research activities for prospective case studies. In prospective case studies, research at the site begins before hydraulic fracturing occurs, and then continues during and after hydraulic fracturing activities. EPA will announce the location of its prospective case studies once sites are selected.
In June 2011, EPA identified five retrospective case study locations to help the agency assess the potential impacts of hydraulic fracturing on drinking water resources. Retrospective case studies occur at sites where hydraulic fracturing has already occurred, and where contamination of drinking water resources has been reported.
The sites identified were selected following extensive input from stakeholders, including the public, local and state officials, industry, and environmental organizations. EPA began field work in some of the selected areas in the summer of 2011:
• Bakken Shale - Killdeer, Dunn County, North Dakota
• Barnett Shale - Wise County, Texas
• Marcellus Shale - Bradford and Susquehanna Counties, Pennsylvania
• Marcellus Shale - Washington County, Pennsylvania
• Raton Basin – Las Animas and Huerfano Counties, Colorado
- Study of the Potential Impacts of Hydraulic Fracturing on Drinking Water Resources: Progress Report (PDF)
- Key issues to be investigated at each location
- Criteria for case study location selection
- June 23, 2011 press release on selection of locations for Hydraulic Fracturing Study Plan
- Questions and answers about EPA's hydraulic fracturing study