An official website of the United States government.

This is not the current EPA website. To navigate to the current EPA website, please go to This website is historical material reflecting the EPA website as it existed on January 19, 2021. This website is no longer updated and links to external websites and some internal pages may not work. More information »

Freedom of Information Act (FOIA)

Oil and Gas Extraction in the Mid-Atlantic

On this page:


​Extraction from "unconventional" resources - shale gas formations, coal beds and tight sands - through the combination of horizontal drilling and hydraulic fracturing, as well as other techniques, has increased at a rapid pace in recent years.

The Marcellus Shale is a sedimentary formation that underlies most of Pennsylvania and West Virginia and extends into parts of Virginia, Maryland, New York and Ohio. It is one of several important gas reserves in the United States and is one of the largest natural gas “plays” in the world. A "play" is the geographic area underlain by a gas or oil containing geologic formation such as the Marcellus Shale.

Development of these gas plays and other unconventional resources presents significant potential for economic development and energy independence, as well as the potential for environmental impacts on land, water and air.

EPA has undertaken a national study to examine potential impacts of hydraulic fracturing to drinking water resources. EPA is also working with federal, state and local partners to ensure public health and the environment are protected as unconventional resource extraction and production activities become a more prominent component of the oil and gas sector.

EPA has received inquiries from the general public and a diverse range of stakeholders regarding a variety of topics related to unconventional resource extraction and oil and gas development in general. In keeping with EPA’s commitment to transparency, EPA Region 3 has developed this Public Reading Room dedicated to providing public access to documentation of EPA’s activities related to key oil and gas topics in the Mid-Atlantic states.

Top of Page

Administrative Orders at Oil and Gas Construction Sites

These are administrative orders addressing violations of section 404 of the Clean Water Act

Top of Page

Clean Water Act Section 308 Information Requests

EPA Requests for Information on Marcellus Shale Flowback Water

On May 12, 2011, EPA’s Mid-Atlantic Region issued information request letters to six natural gas drillers directing them to disclose how and where they dispose of or recycle wastewater generated by their Marcellus Shale natural gas exploration, extraction and production activities. These six companies currently hold more than half of all permits issued for natural gas drilling in Pennsylvania.

EPA’s directive followed an April 19, 2011 request by the Pennsylvania Department of Environmental Protection (PADEP) that by May 19, 2011, natural gas well drilling operators voluntarily stop taking gas extraction wastewater to 15 facilities in Pennsylvania.

The companies were directed to report back to EPA by May 25, 2011 with information on disposal or recycling practices for the wastewater through the development of natural gas wells they own and/or operate in EPA’s Mid-Atlantic Region.

In the letters, EPA required the companies to describe how they intend to handle gas extraction wastewater during 2011. All six companies indicated their intention to employ reuse, disposal, and/or treatment rather than using any of the 15 wastewater treatment facilities referenced in PADEP’s April 19, 2011 request. Some companies expressed an intention to reuse over 90% of gas extraction wastewater in 2011.

Most of this information has been released through the Freedom of Information Act (FOIA). EPA is not endorsing or adopting this information by posting this information on our website.

To facilitate online review of these records, EPA has parsed some files into multiple components and omitted duplicative records.

Responses to EPA's request for information on Marcellus Shale Flowback Water:

Top of Page

Natural Gas Ambient Air Monitoring of Oil & Gas Extraction Site in Southwestern Pennsylvania

EPA Region III conducted a short term ambient air monitoring study in 2012 in Washington County, Pennsylvania. The purpose of the project was to monitor certain air toxic compounds in the outdoor air around natural gas extraction facilities.

Top of Page

Requests for Information from Publicly Owned Treatment Works (POTWs) taking Oil and Gas Waste

Top of Page

Clean Water Act Section 309 Information Requests

Administrative orders and information requests to wastewater treatment facilities accepting wastewater from Marcellus Shale Drilling Operations

Certifications from Sewage Authorities about accepting oil and gas wastewaters

Wastewater treatment facility effluent sampling data submissions

Wastewater treatment facilities in receipt of the Administrative Orders and Information Requests were given the opportunity to sign and return to EPA certifications stating they were no longer accepting oil and gas exploration and/or production wastewaters. Information request recipients that did not sign and return a certification statement were required to conduct and submit additional effluent sampling in addition to their NPDES permit required monthly discharge monitoring reports. These facilities were required to sample effluent for total dissolved solids, chloride, bromide, sulfate, Gross Alpha, Radium 226 and 228, and Uranium.

Top of Page

Wastewater Management

Underground Injection Control

Letters regarding National Pollutant Discharge Elimination System (NPDES) Permits for wastewater treatment facilities in Pennsylvania accepting oil and gas wastewater

Letters from EPA to Publicly Owned Treatment Works (POTWs) in Pennsylvania stating that drilling waste may be a substantial change. July 13, 2011

2013 Sample Letters to Pennsylvania Publicly Owned Treatment Works (POTWs) regarding acceptance of oil and gas waste

Top of Page

Information Provided to EPA by Pennsylvania Department of Environmental Protection (PADEP)

EPA Correspondence with PADEP

Information provided to EPA by PADEP and through information requests to Publicly Owned Treatment Works (POTWs).
Most of this information has been released through the Freedom of Information Act. EPA is not endorsing or adopting this information by posting it on the website.

Voluntary sampling data from oil and gas wastewater treatment facilities

Correspondence between PADEP and wastewater treatment facilities

Letters from Hart Resources

Top of Page

Requests for Information from Publicly Owned Treatment Works (POTWs) taking Oil and Gas Waste

Top of Page