The staff of the Federal Energy Regulatory Commission (FERC or Commission) has prepared an environmental assessment (EA) for the Mountain Valley Pipeline Boost Project (Project), proposed by Mountain Valley Pipeline, LLC (Mountain Valley) in the above-referenced docket.^[1] Mountain Valley requests authorization to construct, modify, and operate facilities along its existing pipeline system in West Virginia and Virginia to provide about 600,000 dekatherms per day of incremental natural gas service on the existing Mountain Valley Mainline.

Any person wishing to comment on the EA may do so. To ensure consideration of your comments on the proposal prior to making a decision on the Project, it is important that the Commission receive your comments on or before 5:00 p.m. Eastern Time on September 8, 2026. Instructions for filing comments are provided on page 3.

FERC is the lead federal agency for authorizing interstate natural gas transmission facilities under the Natural Gas Act of 1938 (NGA) and the lead federal agency for preparation of the EA. The EA assesses the potential environmental effects of the Project in accordance with the requirements of the National Environmental Policy Act (NEPA) ^[2] and the Commission's implementing regulations.^[3] The principal purposes of the EA are to: identify and assess the potential effects on the natural and human environment; describe and evaluate reasonable alternatives; identify and recommend mitigation measures; and facilitate public involvement in the environmental review process. The EA concludes that approval of the Project would not constitute a major federal action significantly affecting the quality of the human environment.

The U.S. Army Corps of Engineers (USACE) Huntington District participated as a cooperating agency in the preparation of the EA. Cooperating agencies have jurisdiction by law or special expertise with respect to resources potentially affected by the proposal and participate in the NEPA analysis. The USACE has authority under section 404 of the Clean Water Act to regulate the discharge of dredged or fill materials into Waters of the United States, as well as sections 10 and 14 of the Rivers and Harbors Act.^[4] Although the cooperating agency provided input to the conclusions and recommendations presented in the EA, the agency will present its own conclusions and recommendations in its respective Record of Decision for the Project.

The EA addresses the potential environmental effects of the construction and operation of the following Project facilities:

• installation of one additional natural gas turbine and auxiliary facilities to increase capacity by 23,470 horsepower (hp) at the existing Bradshaw Compressor Station (CS) in Wetzel County, West Virginia;
• relocation of existing blowdown silencers and installation of one additional natural gas turbine and auxiliary facilities to increase capacity by 52,500 hp and restaging of two existing natural gas turbines at the existing Harris CS in Braxton County, West Virginia;
• relocation of existing blowdown silencers, installation of two additional natural gas turbines and auxiliary facilities, and upgrades to two existing natural gas turbines to increase capacity by 52,880 hp at the existing Stallworth CS in Fayette County, West Virginia; and
• construction of a new compressor station (Swann CS) with three natural gas turbines totaling 136,900 hp; 0.2 mile-long, 42-inch-diameter dual lay natural gas suction and discharge facilities; a pig launcher and receiver; ^[5] a mainline valve; and auxiliary facilities in Montgomery County, Virginia.

The Commission mailed a copy of the Notice of Availability of the Environmental Assessment for the Mountain Valley Pipeline Boost Project to federal, state, and local government representatives and agencies; elected officials; Native American tribes; environmental and public interest groups; potentially affected landowners and other interested individuals and groups; and newspapers and libraries in the Project area. The EA is available only in electronic format. It may be viewed and downloaded from FERC's website ( www.ferc.gov) on the natural gas environmental documents page ( www.ferc.gov/​industries-data/​natural-gas/​environment/​environmental-documents). In addition, the EA may be accessed by using the eLibrary link on FERC's website. Click on the eLibrary link ( elibrary.ferc.gov/​eLibrary/​search), select “General Search” and enter the docket number in the “Docket Number” field, excluding the last three digits ( i.e., CP26-14). Be sure you have selected an appropriate date range. For assistance, please contact FERC Online Support at FercOnlineSupport@ferc.gov or toll free at (866) 208-3676, or for TTY, contact (202) 502-8659.

The EA is not a decision document. It presents Commission staff's independent analysis of the environmental issues for the Commission to consider when addressing the merits of all issues in this proceeding. Under section 7(c) of the NGA, the Commission determines whether interstate natural gas transportation facilities are in the public convenience and necessity and, if so, grants a Certificate of Public Convenience and Necessity to construct and operate them. The Commission bases its decisions on both economic issues, including need, and environmental effects.

Your comments should focus on the EA's disclosure and discussion of potential environmental effects, reasonable alternatives, and measures to avoid or lessen environmental effects. The more specific your comments, the more useful they will be. For your convenience, there are three methods you can use to file your comments with the Commission. The Commission encourages electronic filing of comments and has staff available to assist you at (866) 208-3676 or FercOnlineSupport@ferc.gov. Please carefully follow these instructions so that your comments are properly recorded:

(1) You can file your comments electronically using the eComment feature on the Commission's website ( www.ferc.gov) under the link to FERC Online. This is an easy method for submitting brief, text-only comments on a project;

(2) You can also file your comments electronically using the eFiling feature on the Commission's website ( www.ferc.gov) under the link to FERC Online. With eFiling, you can provide comments in a variety of formats by attaching them as a file with your submission. New eFiling users must first create an account by clicking on “eRegister.” You must select the type of filing you are making. If you are filing a comment on a particular project, please select “Comment on a Filing”; or

(3) You can file a paper copy of your comments by mailing them to the Commission. Be sure to reference the Project docket number (CP26-14-000) in your letter. Submissions sent via the U.S. Postal Service must be addressed to: Debbie-Anne A. Reese, Secretary, Federal Energy Regulatory Commission, 888 First Street NE, Room 1A, Washington, DC 20426. Submissions sent via any other carrier must be addressed to: Debbie-Anne A. Reese, Secretary, Federal Energy Regulatory Commission, 12225 Wilkins Avenue, Rockville, Maryland 20852.

Filing environmental comments will not give you intervenor status, but you do not need intervenor status to have your comments considered. Only intervenors have the right to seek rehearing or judicial review of the Commission's decision. At this point in this proceeding, the timeframe for filing timely intervention requests has expired. Any person seeking to become a party to the proceeding must file a motion to intervene out-of-time pursuant to Rule 214(b)(3) and (d) of the Commission's Rules of Practice and Procedures (18 Code of Federal Regulations 385.214(b)(3) and (d)) and show good cause why the time limitation should be waived. Motions to intervene are more fully described at www.ferc.gov/​how-intervene.

For public inquiries and assistance with making filings such as interventions, comments, or requests for rehearing, contact the Office of Public Participation at (202) 502-6595 or OPP@ferc.gov. Additional information about the Project is available from the FERC website ( www.ferc.gov) using the eLibrary link. The eLibrary link also provides access to the texts of all formal documents issued by the Commission, such as orders, notices, and rulemakings.

In addition, the Commission offers a free service called eSubscription, which allows you to keep track of all formal issuances and submittals in specific dockets. This can reduce the amount of time you spend researching proceedings by automatically providing you with notification of these filings, document summaries, and direct links to the documents. Go to www.ferc.gov/​ferc-online/​overview to register for eSubscription.

(Authority: 18 CFR 2.1)