# Mangum Gas Storage LLC; Notice of Availability of the Environmental Assessment for the Proposed 2025 Amendment Project
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 January 20, 2026. Instructions for filing comments are provided on page 3.
The proposed project is an amendment to the Certificate of Public Convenience and Necessity (Certificate) issued by the Commission on March 17, 2011, as amended on November 17, 2016, and on April 23, 2020, in Docket Nos. CP10-22-000, CP16-18-000, and CP20-77-000, respectively. Currently, Magnum is authorized to construct and operate a natural gas storage facility with a total working gas capacity of 21 billion cubic feet (Bcf) consisting of two storage caverns, one brine disposal pond and associated facilities, compression facilities, a 61.6-mile-long, 36-inch-diameter header pipeline, and other related facilities. The proposed modifications consist primarily of changes to the locations of previously approved facilities and utilities at the storage site. Magnum also requests authorization to redesign two authorized caverns for 5.2 Bcf of working gas each and to construct and operate two additional storage caverns with 5.2 Bcf of working gas capacity each, one additional brine disposal pond and related facilities, and two new pipeline interconnections. Magnum's stated purpose is to modify its Certificate to reflect new construction, operational and commercial needs, and provide new competitive firm and interruptible natural gas storage, hub, and wheeling services in the Western United States.
The EA assesses the potential environmental effects of the Amendment Project in accordance with the requirements of the National Environmental Policy Act (NEPA). The FERC staff concludes that approval of the Amendment Project would not constitute a major federal action significantly affecting the quality of the human environment.
The Amendment Project includes the following facilities within the storage site:
• four below-ground, solution mined storage caverns (CW-3, CW-4, CW-25, and CW-26);
• two water supply wells (GS-MH-4 and GS-MH-5);
• compression, substation, and dehydration and metering facilities;
• two large-scale brine evaporation ponds (Pond 3 and Pond 5);
• maintenance and laydown area;
• office/warehouse building;
• site-wide utility corridors containing water, brine and power lines;
• portions of the 4-inch-diameter, about 9-mile-long gas supply line connected to the local gas distribution company;
• portions of the 36-inch-diameter, about 61.5 mile long header pipeline (Header) and associated block valves that extend from the Storage Site near Delta in Millard County to the interstate pipeline system near Goshen in Utah County;
• two interconnection options to the adjacent Kern River Delta Lateral (a recently constructed pipeline located just east of the Amendment Project); and
• two interconnection options to the Intermountain Power Plant (IPP—a newly constructed hydrogen and natural gas-fired power plant located directly north and adjacent to the Amendment Project).
The Commission mailed a copy of the *Notice of Availability* of the EA to federal, state, and local government representatives and agencies; elected officials; environmental and public interest groups; Native American tribes; potentially affected landowners and other interested individuals and groups; and newspapers and libraries in the Amendment Project area. The EA is only available in electronic format. It may be viewed and downloaded from the FERC's website ( *www.ferc.gov* ), on the natural gas environmental documents page ( *https://www.ferc.gov/industries-data/natural-gas/environment/environmental-documents* ). In addition, the EA may be accessed by using the eLibrary link on the FERC's website. Click on the eLibrary link ( *https://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.,* CP25-233). Be sure you have selected an appropriate date range. For assistance, please contact FERC Online Support at *[email protected]* 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.
Your comments should focus on the EA's disclosure and discussion of potential environmental effects, reasonable alternatives, and measures to avoid or lessen environmental impacts. 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 to the Commission. The Commission encourages electronic filing of comments and has staff available to assist you at (866) 208-3676 or *[email protected].* 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 Amendment Project docket number (CP25-233-000) 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 CFR 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 *https://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 *[email protected].* Additional information about the Amendment 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 *https://www.ferc.gov/ferc-online/overview* to register for eSubscription.
*Authority:* 18 CFR 2.1.
Dated: December 19, 2025.
Debbie-Anne A. Reese,
Secretary.