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Assessment of the Potential Impacts of Hydraulic Fracturing for Oil and Gas on Drinking Water Resources (External Review Draft)

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Abstract

This assessment provides a review and synthesis of available scientific literature and data to assess the potential for hydraulic fracturing for oil and gas to impact the quality or quantity of drinking water resources, and identifies factors affecting the frequency or severity of any potential impacts. The scope of this assessment is defined by the hydraulic fracturing water cycle which includes five main activities:
  1. Water acquisition – the withdrawal of ground or surface water needed for hydraulic fracturing fluids;
  2. Chemical mixing – the mixing of water, chemicals, and proppant on the well pad to create the hydraulic fracturing fluid;
  3. Well injection – the injection of hydraulic fracturing fluids into the well to fracture the geologic formation;
  4. Flowback and Produced water – the return of injected fluid and water produced from the formation to the surface, and subsequent transport for reuse, treatment, or disposal; and
  5. Wastewater treatment and waste disposal – the reuse, treatment and release, or disposal of wastewater generated at the well pad, including produced water.
This report can be used by federal, tribal, state, and local officials; industry; and the public to better understand and address vulnerabilities of drinking water resources to hydraulic fracturing activities.
Hydraulic fracturing in combination with advanced directional drilling techniques has made it possible to economically extract oil and gas from unconventional resources, such as shale, tight formations, and coalbeds. The growth in domestic oil and gas exploration and production made possible by the expanded use of hydraulic fracturing, has raised concerns about its potential for impacts to human health and the environment. Specific concerns have been raised by the public about the effects of hydraulic fracturing on the quality and quantity of drinking water resources.

The U.S. Congress urged the U.S. Environmental Protection Agency (EPA) to study the relationship between hydraulic fracturing and drinking water resources. In 2011, the EPA published its Plan to Study the Potential Impacts of Hydraulic Fracturing on Drinking Water Resources. The research described in the Study Plan began the same year and has resulted in 12 EPA reports and several journal publications. This assessment uses the results from EPA-led research projects and the results of hundreds of other publications to provide a synthesis of the science related to hydraulic fracturing and drinking water resources.

Impact/Purpose

To assess the potential impacts of hydraulic fracturing on drinking water resources, if any, and to identify the driving factors that may affect the severity and frequency of such impacts.

Status

The draft assessment was peer reviewed by the EPA’s Science Advisory Board (SAB). The SAB issued their final report on August 11, 2016. The EPA released the final report, Hydraulic Fracturing for Oil and Gas: Impacts from the Hydraulic Fracturing Water Cycle on Drinking Water Resources in the United States, on December 13, 2016.

Citation

U.S. EPA. Assessment of the Potential Impacts of Hydraulic Fracturing for Oil and Gas on Drinking Water Resources (External Review Draft). U.S. Environmental Protection Agency, Washington, DC, EPA/600/R-15/047, 2015.

History/Chronology

Date Description
01- Dec 2012 EPA released a Progress Report in December 2012 outlining what the Agency had done to date, as well as next steps. The Progress report did not provide conclusions or answers to the study questions.
02- Jun 2015 EPA released the draft report to the Science Advisory Board (SAB) for public comment and peer review. [SAB FR Notice Jun 4, 2015]
03- Jul 2015 EPA released the supporting database prior to the external peer review meeting. (see downloads)
04- Oct 2015 EPA's Science Advisory Board (SAB) hosted a public peer review meeting to discuss the draft report. SAB Advisory meeting and report development page.
05- Aug 2016 EPA's Science Advisory Board (SAB) released their final peer review report.
06- Dec 2016 EPA released the final report, Hydraulic Fracturing for Oil and Gas: Impacts from the Hydraulic Fracturing Water Cycle on Drinking Water Resources in the United States following public comments and peer review.
07- Jan 2017 EPA released the EPA Response to SAB Comments on the Review of the Draft Report.

Additional Information

Comments on the draft assessment may be submitted and reviewed using the e-Government Regulations.gov Web site. From the site, select “Environmental Protection Agency” and the keyword “EPA-HQ-OA-2015-0245 (for the docket ID) to comment on this report.

Download(s)

This download(s) is distributed solely for the purpose of pre-dissemination peer review under applicable information quality guidelines. It has not been formally disseminated by EPA. It does not represent and should not be construed to represent any Agency determination or policy.

  • Assessment of the Potential Impacts of Hydraulic Fracturing for Oil and Gas on Drinking Water Resources (External Review Draft) -- (EPA/600/R-15/047) (PDF)  (998  pp, 25.8 MB, about PDF)
  • Assessment of the Potential Impacts of Hydraulic Fracturing for Oil and Gas on Drinking Water Resources -- Executive Summary (PDF)  (28  pp, 1.1 MB, about PDF)
  • Assessment of the Potential Impacts of Hydraulic Fracturing for Oil and Gas on Drinking Water Resources -- Main Report (PDF)  (599  pp, 20.8 MB, about PDF)
  • Assessment of the Potential Impacts of Hydraulic Fracturing for Oil and Gas on Drinking Water Resources -- Appendices (PDF)  (401  pp, 5.6 MB, about PDF)
  • Draft Charge Questions to Reviewers
  • EPA's Response to the SAB Review of the Draft Report (Jan 2017) (PDF)  (228  pp, 1.5 MB, about PDF)

Related Link(s)

  • Hydraulic Fracturing Study Fact Sheets
  • SAB Hydraulic Fracturing Drinking Water Assessment
  • SAB Review of EPA’S Draft Assessment of the Potential Impacts of Hydraulic Fracturing for Oil and Gas on Drinking Water Resources
  • Plan to Study the Potential Impacts of Hydraulic Fracturing on Drinking Water Resources (Nov 2011)
  • Hydraulic Fracturing Study Fact Sheets
  • Compilation of Physicochemical and Toxicological Information About Hydraulic Fracturing-Related Chemicals (Draft Database)
  • Study of the Potential Impacts of Hydraulic Fracturing on Drinking Water Resources: Progress Report (Dec 2012)
  • Hydraulic Fracturing for Oil and Gas: Impacts from the Hydraulic Fracturing Water Cycle on Drinking Water Resources in the United States (Final Report)

Federal Register Notices

  • SAB FR Notice: Jun 5, 2015
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Last updated on January 24, 2017
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