The U.S. EPA has issued a 278-page Progress Report on its study of the potential impacts of hydraulic fracturing on drinking water resources. The report outlines the framework for the final study, but does not draw any conclusions. Those will be made in the final study.
The Executive Summary says that the work is arranged around the five stages of the hydraulic fracking water cycle and questions about the possible impacts on drinking water resources of:
- large volume water withdrawals from ground and surface waters;
- hydraulic fracturing fluid surface spills on or near well pads;
- the injection and fracturing process;
- flowback and produced water surface spills on or near well pads; and
- inadequate treatment of hydraulic fracturing wastewater
- analysis of existing data on chemicals and practices; data is drawn from nine companies that hydraulically fractured 24,925 wells between September 2009 and October 2010, and additional data on chemicals and water use for hydraulic fracturing from over 12,000 well-specific chemical disclosures in FracFocus. EPA is evaluating data on causes and volumes of spills of hydraulic fracturing fluids and wastewater drawn from state spill databases in Colorado, New Mexico, and Pennsylvania, and from the National Response Center national database of oil and chemical spills;
- scenario evaluations, including potential impacts to drinking water sources from withdrawing large volumes of water in the Upper Colorado River Basin and the Susquehanna River Basin;
- laboratory studies on potential impacts of inadequately treating hydraulic fracturing wastewater and discharging it to rivers;
- toxicity assessments of chemicals used in hydraulic fracturing fluids from 2005 to 2011 and chemicals found in flowback and produced water; and
- case studies of locations in Colorado, North Dakota, Pennsylvania (in Bradford and Washington counties), and Texas
EPA is also reviewing scientific literature relevant to the study’s research questions.
Results of the study are expected to be released in a draft for public and peer review in 2014.