EPA's Study of Hydraulic Fracturing and Its Potential Impact on Drinking Water Resources

Questions and Answers about EPA's Hydraulic Fracturing Study

General Study Background

Hydraulic Fracturing Study Draft Assessment 

Peer Review and Quality Assurance Process

Stakeholder Outreach and Engagement 

Case Studies


General Study Background

Q: Why is EPA doing this study?

A: Responsible development of America's unconventional oil and natural gas resources offers important economic, energy security and environmental benefits. The EPA is committed to study and addressing potential concerns related to unconventional oil and natural gas development so that the public has confidence that it will proceed in a safe and responsible manner. In its FY2010 Appropriations Committee Conference Report, Congress urged the EPA to study the relationship between hydraulic fracturing and drinking water, using the best available science, independent sources of information, and to conduct the study in consultation with others using a transparent, peer-reviewed process. The EPA announced in March 2010 that it would conduct a research study to investigate the potential impacts of hydraulic fracturing on drinking water resources. 

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Q: What topics fall outside of this study’s scope?

A: EPA recognizes that the public has raised concerns about hydraulic fracturing that extend beyond the potential impacts on drinking water resources. Areas that fall outside of this study’s scope include, for instance: air impacts, ecological effects, seismic risks, specific health impacts, public safety, and occupational risks. For more information, see chapter 13 of the Final Study Plan.

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Hydraulic Fracturing Study Draft Assessment 

Q: What is the purpose of the draft assessment and how will it be used?

A: The draft assessment represents the state-of-the-science on hydraulic fracturing and its potential impacts on drinking water. The assessment is based upon the results of an extensive review of literature, results from EPA research projects, and input from industry, states, and other stakeholders. The overall purpose of the report is to:

  • Contribute to the understanding of potential impacts of hydraulic fracturing on drinking water resources.
  • Inform and promote dialogue among federal, tribal, state, and local government entities, industry, non-governmental organizations, and other stakeholders.
  • Identify knowledge gaps and information needs.

Once final, after review by the Scientific Advisory Board and public review and comment, the assessment will be an important resource for states, tribes, and industry to protect public health and drinking water resources more effectively.

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Q: What types of potential impacts are addressed in the draft assessment?

A: The draft assessment addresses potential impacts to drinking water resources at each stage of the hydraulic fracturing water cycle. These include: water acquisition, chemical mixing, well injection, flowback and produced water, and wastewater treatment and disposal. Within this, the EPA looked at:

  • Normal hydraulic fracturing operations reflecting modern typical practices.
  • Potential and actual accidents or unintended events associated with hydraulic fracturing activities.
  • Potential immediate, short-term, and long-term impacts of hydraulic fracturing activities.

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Q: Has the EPA determined specific health effects of any impacts to drinking water?

A: This study is not a human health assessment or a risk assessment; it is not site specific; it does not identify or evaluate best management practices; it is not designed to inform specific policy decisions; nor does it identify or evaluate policy options. 

The draft assessment is the most complete compilation to date of the scientific information available on the potential impacts of hydraulic fracturing on drinking water resources. Based on the available data, the EPA identified important vulnerabilities in the hydraulic fracturing water cycle that can potentially impact drinking water resources.

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Q: Does this assessment either assess existing regulations or recommend any new regulations?

A: No. This assessment does not address exisiting regulations, nor does it recommend any new regulations. However, we believe when final it provides states and tribes a valuable resource to protect current and future drinking water resources.

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Q: What sources of information support the draft assessment?

A: The draft assessment includes data from over 700 sources of information including:

  • published papers;
  • numerous technical reports;
  • results from peer reviewed agency research; and
  • information provided by industry, states, tribes, non-governmental organizations, and other interested members of the community.

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Q: How can the public comment on the draft assessment?

A: Written Statements: Members of the public wishing to provide written comments may submit them to the EPA Docket electronically via www.regulations.gov, by e-mail, by mail, by fascimile, or by hand delivery/courier. Please follow the detailed instructions provided in the written statements section of the Federal Register Notice.

Oral Statements: In general, individuals or groups requesting to present an oral statement at a public teleconference will be limited to three minutes per speaker. To be placed on the public speaker list for the September 30, 2015 teleconference, intested parties should notify Mr. Edward Hanlon, Designated Federal Office, by telephone: (202) 564-2134 or email at hanlon.edward@epa.gov, by e-mail no later than September 23, 2015. In general, individuals or groups requesting to present oral statements at the face-to-face public meeting will be limited to five minutes. Interested parties should contact Mr. Edward Hanlon, DFO, in writing (preferably via e-mail) at the contact information noted above by October 13, 2015 to be placed on the list of public speakers for the October 28-30, 2015 meeting.

Additional information on how the public can submit oral and written comments on the agency's draft report "Assessment of the Potential Impacts of Hydraulic Fracturing for Oil and Gas on Drinking Water Resources", (May, 2015 External Review Draft, EPA/600/R-15/047) can be found in the Federal Register Notice published on June 5, 2015 that announces a public meeting and three teleconferences of the SAB Hydraulic Fracturing Research Advisory Panel to conduct a review of the EPA draft assessment. 

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Q: How long it the comment period for the draft assessment?

A: The public comment period is 85 calendar days. For written statements to be considered in the SAB's September 30, 2015 teleconference and October 28-30, 2015 face-to-face meeting, they should be received in the EPA Docket by August 28, 2015. All written statements received by August 28, 2015 will be made available to the SAB Panel sufficiently in advance of the teleconference and meeting for the Panel's consideration.

Public comments submitted after August 28, 2015 will be made available to the SAB Panel as soon as practicable. Learn more about the SAB's review process for the draft assessment

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Q: Is EPA planning future research related to hydraulic fracturing?

A: In the President's FY2016 Budget, EPA requested $12.1 million for research related to hydraulic fracturing. EPA requested $8.1 million to study (a) the potential impacts of hydraulic fracturing on water and ecosystems, and (b) air quality to support sustainable approaches to oil and natural gas development and production. The remaining $4.0 million was request to respond to the comment received from the SAB and the public on the Draft Hydraulic Fracturing Drinking Water Assessment, thereby enabling the Agency to finalize the assessment. The FY2016 budget request was developed in consultation with other Federal agencies and is consistent with the Federal Multiagency Collaboration on Unconventional Oil and Gas Research Strategy.

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Peer Review and Quality Assurance Process

Q: How did you determine what sources of information would be included?

A: EPA applied the Agency's assessment factors and the Office of Management and Budget's (OMB) guidelines for peer review to evaluate the quality of all scientific and technical information considered in the study. The assessment factors and guidelines allowed EPA to take into consideration different sources of scientific and technical information, and ensured appropriate and consistent review and weight was given to literature used in the study. We reviewed over 3,500 sources of information ultimately citing 700 including: 

  • published papers;
  • numerous technical reports; 
  • results from peer reviewed agency research; and
  • information provided by industry, states, tribes, non-governmental organizations, and other interested members of the community.

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Stakeholder Outreach and Engagement 

Q: How did the EPA work with stakeholders, including industry, non-governmental organizations, and other state and federal agencies, to conduct the study?

A: Stakeholder input has played an important role in the hydraulic fracturing study. EPA has engaged stakeholders through:

  • technical workshops,
  • technical roundtables,
  • public webinars and informational meetings,
  • federal, state, and tribal partner consultations,
  • sector-specific meetings,
  • opportunities to submit electronic or written comments

For more detail on how EPA has been working with stakeholders, please see our "How You Can Get Involved" page.

In addition, EPA has worked with stakeholders to gather and understand specific sources of data for the following research projects:

  • Review of State and Industry Spill Data: The EPA reviewed data sources obtained from agencies in the following nine states: Arkansas, Colorado, Louisiana, New Mexico, Oklahoma, Pennsylvania, Texas, Utah, and Wyoming.
  • Retrospective Case Studies: The EPA worked closely with state agencies to conduct the research.
  • Wastewater Treatment Studies: The EPA worked with state agencies and wastewater treatment facilities in Pennsylvania to obtain samples of raw and treated hydraulic fracturing wastewater.
  • Well File Review: The EPA reviewed and analyzed information about hydraulically fractured oil and gas production wells that were provided by nine well operating companies. The EPA also met with the companies to ensure that we had an accurate understanding of the information they provided. 
  • FracFocus: The Ground Water Protection Council provided the EPA with information reported by oil and gas operators to FracFocus, a publicly accessible hydraulic fracturing chemical registry developed by the Ground Water Protection Council and the Interstate Oil and Gas Compact Commission.

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Q: How is EPA working with other federal agencies?

A: EPA works with other federal agencies through the Federal Multiagency Collaboration on Unconventional Oil and Gas Research. The US Department of Energy, the US Department of the Interior, and the US Environmental Protection Agency signed a joint memorandum to work together to address the highest priority research associated with safely and prudently developing important domestic unconventional oil and gas resources.  In addition, Health and Human Services scientists and engineers are members of the Technical Subcommittee, which developed the priority research needs or effects on human health.  For more information, please visit http://unconventional.energy.gov/.

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Case Studies

Q: What are retrospective case studies?

A: Retrospective case studies were conducted at locations where hydraulic fracturing had already occurred, and where residents had reported concerns about contamination of drinking water resources. Through these case studies EPA sought to identify whether there was an impact and then tried to determine potential causes for those impacts.

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Q: Why were case studies being conducted as part of EPA's hydraulic fracturing study?

A: The retrospective case studies represent a subset of cases where questions have been raised about potential impacts from hydraulic fracturing. Through these case studies EPA sough to identify whether there was an impact, and then tried to determine potential causes for those impacts.

These five case studies provide valuable insights into vulnerabilities and potential pathways for impacts to drinking water resources from hydraulic fracturing activities, such as: surface activities (including impoundments, well pads, and associated spills), and well construction and integrity.

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Q: Where did the EPA conduct retrospective case studies? 

A: EPA selected case studies that the Agency believesd would provide the most useful information about the potential impacts of hydraulic fracturing on drinking water resources under a variety of circumstances.

EPA selected five retrospective case studies located in:

• 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 
 

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Q: How were the retrospective case study sites chosen?

A: Through a stakeholder process (2010-2011), EPA invited the public to nominate specific regions of the U.S. for inclusion in the case studies. EPA selected five retrospective case study sites for the over 40 nominated sites. These case studies were chosen to represent a wide range of conditions that may have resulted from hydraulic fracturing activities. (Learn more about the criteria used to determine case study locations)

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Q: What is the difference in well types for the retrospective case studies?

A: 

  • Domestic well – A homeowner well that serves as source of potable and/or irrigation water for the household.
  • Surface water – Water naturally open to atmosphere (e.g. lakes, streams, ponds, etc.).
  • Municipal well – A water supply well operated by a city or town agency or government.
  • Water supply well – A well operated to supply water for oil and gas activities.
  • Production well – A well used to retrieve petroleum or gas from an underground reservoir.
  • Monitoring well – A well installed to obtain water quality samples or measure groundwater levels.

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Q: Did EPA notify homeowners at the case study locations when exceedances were found?

A: EPA provided each affected homeowner with a letter summarizing sampling activities, a summary of any exceedances, and copies of the full data reports associated with their domestic well and surface water.  Homeowners were also provided a phone number to call if they had questions, and Health Consultations were offered in coordination with the Agency for Toxic Substance and Disease Registry.   

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Q: What is the current status of the prospective case studies?

A: We have been unable to find a suitable location that meets both the scientific criteria of a rigorous prospective study and the business needs of potential partners. For a location to be suitable, it is necessary to gather a minimum of one year of characterization data for ground water and surface water prior to and following unconventional exploration activities in the study area, and for there to be no other hydraulic fracturing activities on adjacent properties during the entire study period, which could last several years. Since we have been unable to identify suitable locations within the timeframe of the study, results from prospective case studies will not be available in time to inform the development of the study’s draft assessment report.

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