The agency said it will begin field work in some of the selected regions this summer. 

The Marcellus Shae in Washington County, PA was one of two sites selected for prospective case studies where EPA will monitor key aspects of the hydraulic fracturing process throughout the life cycle of a well.  The second case study will focus on the Haynesville Shale in DeSoto Parish, La.

Five retrospective case studies were selected and will examine areas where hydraulic fracturing has occurred for any impact on drinking water resources. The Pennsylvania locations chosen for this portion of the study are in Bradford, Susquehanna and Washington counties.  The other locations are in North Dakota, Texas and Colorado. 

EPA says the information gathered will be part of an approach which includes literature review, collection of data and information from states, industry and communities, laboratory work and computer modeling.

“The combination of these materials will allow us to do a more comprehensive assessment of the potential impacts of hydraulic fracturing on drinking water resources, ” the agency said in a news release. “The study will continue to use the best available science, independent sources of information, and will be conducted using a transparent, peer-reviewed process, to better understand any impacts associated with hydraulic fracturing.”