Keeping with the Agency's previously announced schedule, the Environmental Protection Agency (EPA) released a progress report on its ongoing "Plan to Study the Potential Impacts of Hydraulic Fracturing on Drinking Water Resources". The Progress Report outlines the framework for the final study, which is scheduled to be completed in 2014, and highlights the work currently underway and the status of 18 research projects as of September 2012. Just about midway through the study period, EPA has taken a few research questions off the table to avoid overlap with the work of other federal agencies and dropped one of the prospective case studies. Still, the overall focus of the study is rather broad and the Agency continues to spend a significant amount of resources looking into drilling operations not uniquely associated with the hydraulic fracturing process.
The Agency began its hydraulic fracturing study in 2011 with the goal of assessing the potential impacts of hydraulic fracturing on drinking water resources. EPA is focusing the study on five stages of the hydraulic fracturing water cycle: water acquisition, chemical mixing, well injection, flowback and produced water, and wastewater treatment and waste disposal. EPA outlined the following primary research questions associated with each of the five stages:
- Water acquisition: What are the possible impacts on drinking water resources of large volume water withdrawals from ground and surface waters?
- Chemical mixing: What are the possible impacts of hydraulic fracturing fluid surface spills on or near well pads on drinking water resources?
- Well injection: What are the possible impacts of the injection and fracturing process on drinking water resources?
- Flowback and produced water: What are the possible impacts of flowback and produced water (collectively referred to as "hydraulic fracturing wastewater") surface spills on or near well pads on drinking water resources?
- Wastewater treatment and waste disposal: What are the possible impacts of inadequate treatment of hydraulic fracturing wastewater on drinking water resources?
The Progress Report details EPA's ongoing research and describes the work undertaken to address the primary questions along with numerous secondary research questions. The following are a few of the more interesting takeaways from the Progress Report:
- EPA Discontinues Work on Interactions Between Chemicals and Rock Formations - EPA will no longer study the interactions between hydraulic fracturing fluids and various rock formations. The Agency will thus not consider whether hydraulic fracturing fluids change the fate and transport of subsurface substances through geochemical interactions; or, the chemical, physical, and toxicological properties of subsurface substances that may be released by hydraulic fracturing operations. EPA has instead elected to rely on research in this area being conducted by the US Department of Energy and academic institutions.
- EPA Drops Louisiana Case Study - The EPA prospective case study proposed for De Soto Parish, Louisiana, in the Haynesville Shale has been dropped due to "scheduling conflicts."
- EPA Intends to Mine Data from FracFocus - EPA is pulling additional data on chemicals and water use for hydraulic fracturing from over 12,000 well-specific chemical disclosures in FracFocus. The Agency's use of FracFocus appears to be an added benefit of the industry-led disclosure database designed to provide information to the public.
- Consolidated List of Chemicals and Searchable Website - EPA includes in Appendix A to the Progress Report a consolidated list of chemicals used in fracturing fluids or those chemicals found in flowback or produced water. The list was compiled from information obtained from service providers, operators, and FracFocus. While EPA has assigned a chemical structure to most of these chemicals, just over 400 substances were "too poorly defined" to be designated as unique substances. EPA plans to create a website to be used as a public forum for publishing downloadable, structure-searchable, and standardized chemical structure files associated with chemical inventories and toxicity datasets.
- Case Study Sampling - EPA provides maps of the sampling locations in some instances. So far, EPA has conducted two rounds of sampling at five case study locations in Colorado, North Dakota, Pennsylvania, and Texas. Water samples have been collected from over 70 domestic water wells, 15 monitoring wells, and 13 surface water sources, among others. EPA is using this sample data in order to identify the source of any contamination. EPA expects to conduct additional sampling at most locations.
- Modeling Gas/Fluid Migration - EPA is using computer models to explore the possibility of subsurface gas and fluid migration from deep shale formations to overlying aquifers in certain scenarios (including poor well construction and hydraulic communication via fractures). The Agency is also using models to estimate chemical, physical, and toxicological properties for chemicals where such information is lacking.
EPA has scheduled public webinars on the Progress Report on January 3 and 4, 2013. After that, EPA has planned a series of technical workshops throughout 2013, the first of which will focus on Analytical Chemical Methods and is scheduled for February 25, 2013. The remaining technical workshops are tentatively scheduled for April and June 2013 and will focus on Water Acquisition, Wastewater Treatment and Modeling, Well Construction/Operation and Subsurface Modeling, and the Case Studies.