The staff of the Federal Energy Regulatory Commission (FERC or Commission) will prepare a draft and final environmental impact statement (EIS) to evaluate potential environmental impacts of the continued operation and maintenance of the proposed Penobscot Mills Hydroelectric Project (Penobscot Mills Project; FERC No. 2458) and the Ripogenus Hydroelectric Project (Ripogenus Project; FERC No. 2572) (herein, the projects). The Penobscot Mills Project is located on the West Branch of the Penobscot River (West Branch) and Millinocket Stream in Piscataquis and Penobscot Counties, Maine. The Ripogenus Project is located on the West Branch in Piscataquis and Penobscot Counties, Maine.^[1] The Commission will use the EIS in its decision-making process in accordance with the National Environmental Policy Act (NEPA). The schedule for preparing the EIS is discussed in the Schedule for Environmental Review section of this notice.

As part of the NEPA review process, the Commission takes into account concerns the public may have about proposals and the environmental impacts that could result whenever it considers the issuance of a license. This gathering of public input is referred to as “scoping.” On August 10, 2021, Commission staff issued Scoping Document 1 requesting comments on environmental issues and study needs for the proposed projects, initiating the scoping process for the projects. Commission staff, in collaboration with the applicant (Great Lakes Hydro America, LLC; GLHA), conducted a virtual environmental site visit that was open to the public on September 9, 2021, and held two virtual public scoping meetings on September 9 and 10, 2021.^[2] A court reporter recorded oral comments made during the scoping meetings. On November 22, 2021, Commission staff issued a revised scoping document (Scoping Document 2) based on the comments received during the scoping comment period, which ended October 9, 2021. Scoping Document 2 described the project, project alternatives, and staff's view, at the time, of anticipated environmental effects that would be addressed in the EIS.

In accordance with the Commission's regulations, on June 29, 2026, Commission staff issued notices that the projects were ready for environmental analysis and soliciting comments, recommendations, preliminary terms and conditions, and preliminary prescriptions (REA Notices). The comment period for the REA Notices ( printed page 64916) closed on August 28, 2026. Based on the information in the record, including comments filed during scoping and in response to the REA Notices, staff has determined that licensing the projects may constitute a major federal action significantly affecting the quality of the human environment. Therefore, staff will prepare a draft and final EIS for the proposed Penobscot Mills and Ripogenus projects, which will address the concerns raised during prior comment periods and comments received in response to this notice.

By this notice, the Commission requests any additional comments on the scope of issues to address in the EIS, including comments on potential alternatives and impacts, and any relevant information, studies, or analyses of any kind concerning impacts affecting the quality of the human environment. If you previously submitted comments and recommendations to the Commission, you do not need to file those comments and recommendations again. To ensure that your comments are timely and properly recorded, please submit your comments so that the Commission receives them in Washington, DC by 5:00 p.m. Eastern Time on November 6, 2026.

Public Participation

There are three methods you can use to submit your comments to the Commission. The Commission encourages electronic filing of comments and has staff available to assist you at (866) 208-3676, or at 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, which is located on the Commission's website ( www.ferc.gov) under the link to FERC Online. Using eComment is an easy method for submitting brief, text-only comments on a project;

(2) You can file your comments electronically by using the eFiling feature, which is located 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 will be asked to select the type of filing you are making; a comment on a particular project is considered a “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 projects' docket numbers (P-2458-273 and/or P-2572-141, as appropriate) on 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.

Additionally, the Commission offers a free service called eSubscription. This service provides automatic notification of filings made to subscribed project dockets, document summaries, and direct links to the documents. Go to www.ferc.gov/​ferc-online/​overview to register for eSubscription.

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.

Summary of the Penobscot Mills and Ripogenus Projects

On September 30, 2024, GLHA filed applications for new major licenses to continue to operate and maintain the existing 67.9-megawatt (MW) Penobscot Mills Project and the existing 37.5-MW Ripogenus Project. Neither project occupies federal land.

Existing Project Facilities

Penobscot Mills Project

The Penobscot Mills Project consists of: (1) four hydropower developments (North Twin, Millinocket, Dolby, and East Millinocket; located between river mile 15 and river mile 2 on the West Branch) that include (a) water retaining features ( e.g., dam/spillway, flashboards/rubber dam, and dikes), (b) water conduits/canals and penstocks, (c) intake structures equipped with trash racks, (d) four powerhouses, and (e) transmission equipment ( e.g., transmission lines); (2) a pool-and-weir fish passage facility at the North Twin Development; and (3) one storage development (Millinocket Lake Storage Development; located on Millinocket Stream). The Penobscot Mills Project generates an average of 324,346 megawatt-hours of energy annually.^[3]

The North Twin Development impoundment is at the upstream end of the Penobscot Mills Project and receives flow from the Ripogenus Project (described below). Releases from the North Twin Development pass through three other developments ( i.e., Millinocket, Dolby, and East Millinocket). The Millinocket Lake Storage Development includes a pumping station through which water can be pumped to Ambajejus Lake (within the North Twin Development impoundment). Water not pumped to Ambajejus Lake is discharged to Millinocket Stream, which enters the West Branch at Shad Pond, downstream of the Millinocket Development, then passes through the Dolby and East Millinocket Developments. The project also includes two battery energy sites that operate as a single battery energy storage system to enhance system reliability.

Ripogenus Project

The Ripogenus Project is located about 21 river miles upstream of the Penobscot Mills Project on the West Branch, and consists of: (1) the Ripogenus impoundment, which (a) is about 20.8 miles long, (b) has a surface area of about 29,270 acres at a normal full pond elevation of 941.59 feet National Geodetic Vertical Datum of 1929 (NGVD 29), and (c) has a usable storage of about 688,705 acre-feet, with a maximum drawdown of 44 feet (to elevation 897.59 feet NGVD 29); and (2) Umbazooksus Lake, which has a surface area of 1,600 acres. Ripogenus dam is 795 feet long and includes two concrete spillway sections, an intake section, a gated sluice section, and an earthen section. The Ripogenus Project generates an average of 221,341 megawatt-hours of energy annually.^[4]

Water flows from the Ripogenus impoundment through a single intake structure, which directs water through a tunnel and penstocks to the powerhouse (McKay Station). The powerhouse contains three turbine-generating units, with a total rated capacity of 37.5 MW. Power generated at the project is transmitted to the electric grid via three transformers and a 29.4-mile-long transmission line. An additional 0.75-mile-long transmission line extends from the McKay Substation to Ripogenus dam. The project has one battery energy storage site to enhance system reliability.

Project Operation

Penobscot Mills Project

The five developments of the Penobscot Mills Project are operated as an integrated system, along with upstream storage projects, including the Ripogenus Project, to manage ( printed page 64917) downstream water levels and flows. GLHA operates the North Twin Development as a store-and-release facility, and uses storage in the Millinocket Lake Storage Development impoundment, as necessary, to maintain impoundment levels at the North Twin Development. The two storage developments (North Twin and Millinocket Lake Storage) are located upstream of the run-of-release developments (Millinocket, Dolby, and East Millinocket). GLHA releases a minimum flow of 60 cubic feet per second (cfs) from the Millinocket Lake Storage impoundment to Millinocket Stream from May 1 through October 15, and 60 cfs or inflow, whichever is less, from October 16 through April 30. A continuous minimum flow of 3,000 cfs is released from August 22 through October 15 to the West Branch downstream of the North Twin Development when impoundment elevation exceeds 488.42 feet NGVD29, otherwise sufficient flow is released to meet a 2,000-cfs minimum flow requirement downstream of Shad Pond.

Ripogenus Project

The Ripogenus Project is operated as a store-and-release development, with an annual seasonal drawdown that allows for management of water levels and flows downstream of the project. GLHA releases a seasonal minimum flow of 100 cfs into the dewatered section of the West Branch downstream of Ripogenus dam from July 1 through September 30, and 12 cfs leakage the remainder of the year, as well as seasonally variable flows through the McKay Station generating units to protect aquatic habitat and to provide whitewater boating opportunities in the West Branch. GLHA also releases 400 cfs from McKay Station to the West Branch during outages of the generating units and diverts 35 to 65 cfs (depending on flow conditions in the West Branch) to the Holbrook side channel, seasonally, to enhance aquatic habitat. The project provides storage capacity to reduce downstream flooding and provide releases during droughts.

Applicant's Proposed Measures

Penobscot Mills Project

GLHA proposes to continue to operate: (1) the North Twin Development for generation and seasonal storage, with target impoundment elevations of 490.42 feet NGVD 29 from May 1 through August 21 and 488.42 feet NGVD 29 from August 22 through October 15, and provide flows necessary to meet the 3,000/2,000-cfs flow requirement in the West Branch downstream of Shad Pond; (2) the Millinocket Lake Storage Development to (a) maintain impoundment elevation between 470 feet and 480 feet NGVD 29, and (b) provide a minimum flow of 60 cfs, or inflow (seasonally), to Millinocket Stream; and (3) the Millinocket, Dolby, and East Millinocket Developments as run-of-release facilities. GLHA also proposes to: (1) continue to operate and maintain the upstream pool-and-weir fish passage structure at North Twin dam; (2) post lake level (for North Twin and Millinocket Lake Storage) and streamflow information on Brookfield Renewable, N.A.'s SafeWaters website; ^[5] (3) maintain the 200-foot conservation buffer and 100-foot vegetation buffer around the Millinocket Lake Storage, North Twin, Millinocket, and Dolby Development impoundments; and (4) maintain Umbazooksus Lake as wetland and wildlife habitat. Lastly, GLHA proposes to: (1) release a year-round 200-cfs minimum flow from Stone dam at the Millinocket Development; (2) provide upstream and downstream American eel passage, conduct upstream American eel studies, and develop a fishway operation and maintenance plan; (3) provide seasonal whitewater boating flows of 600 cfs in Millinocket Stream; and (4) develop an updated wildlife management area plan, a recreation plan, a shoreline management plan, and a historic properties management plan.

Ripogenus Project

GLHA proposes to continue operating the Ripogenus Project as a store-and-release facility. GLHA would continue to: (1) release flows ranging from 12 to 100 cfs from Ripogenus dam to the bypassed reach; (2) provide a station outage flow of 400 cfs downstream of McKay Station; (3) continue to operate and maintain the Holbrook side channel as habitat for Atlantic salmon and brook trout; (4) maintain the 200-foot conservation buffer and 100-foot vegetation buffer around the Ripogenus impoundment; and (5) maintain Umbazooksus Lake as wetland and wildlife habitat. GLHA also proposes to: (1) provide a year-round minimum flow of 1,700 cfs downstream of McKay Station for aquatic habitat; (2) provide seasonally-adjusted flows for whitewater boating; (3) fund the installation, operation, and maintenance of a U.S. Geological Survey flow gage downstream of McKay Station (near Big Eddy); (4) post impoundment level and flow information on Brookfield Renewable, N.A.'s SafeWaters website; and (5) develop a recreation plan, shoreline management plan, common loon management plan, and historic properties management plan.

The purpose of the projects is to continue to provide a source of hydroelectric power for Maine and the Northeast Region. Therefore, under the provisions of the Federal Power Act (FPA), the Commission must decide whether to issue licenses to GLHA for the projects, and what conditions should be placed on any licenses issued.

The NEPA Process and the EIS

The draft and final EIS issued by the Commission will discuss impacts that could occur because of the proposed projects under the following relevant general resource areas:

• geology and soil resources;
• water and aquatic resources;
• terrestrial resources;
• federally threatened and endangered species;
• recreation, land use, and aesthetics;
• cultural resources;
• socioeconomic resources; and
• developmental resources.

Some of the potential effects include: (1) erosion and sedimentation; (2) the timing and magnitude of operational flows in the West Branch (including McKay Station outage flows) and Millinocket Stream on water quality and aquatic resources, including associated effects on (a) littoral and riparian habitat, (b) resident fish, as well as aquatic insects and other macroinvertebrates, (c) freshwater mussels, (d) migration of American eel and the federally listed Atlantic salmon in the Penobscot River Basin; (3) impoundment drawdowns and associated effects on (a) littoral habitat and associated aquatic communities ( e.g., rainbow smelt), (b) landlocked salmon access to tributaries for spawning, (c) wetland habitats, and (d) recreation and aesthetics; (4) availability of upstream habitat and downstream passage survival of American eel; (5) disturbance of suitable habitat for special-status wildlife species, including federally listed species; (6) spread of non-native, invasive species on native species; (7) whitewater boating flows in the West Branch (Upper Gorge and downstream from Stone dam) and Millinocket Stream and associated effects on other resources ( e.g., aquatic habitat and species, angling); (8) recreation facility maintenance and access to the project lakes and free-flowing reaches of the West Branch and Millinocket Stream for ( printed page 64918) recreation and other uses; and (9) cultural resources.

Commission staff will also make recommendations on how to lessen or avoid impacts on the various resource areas. Your comments will help staff focus its analysis on the issues that may have a significant effect on the human environment.

The draft and final EIS will present Commission staff's independent analysis of the issues. On August 10, 2021, Commission staff issued a notice of GLHA's intent to file relicense applications for the projects, which also invited agencies wishing to cooperate in the preparation of the environmental document. No agencies filed requests for cooperating status. A draft EIS will be issued for public comment and circulated for review by all interested parties. Staff will consider all timely comments received during the comment period on the draft EIS and revise the document, as necessary, before issuing a final EIS. The draft and final EIS will be available in electronic format in the public record through eLibrary.^[6] If eSubscribed, you will receive an instant email notification when the environmental document is issued.

Alternatives Under Consideration

As part of our review in the EIS, the Commission will consider a range of reasonable alternatives for each project that are technically and economically feasible and meet the purpose and need for the proposed actions. Alternatives that do not meet these requirements will be summarized and dismissed from further consideration in the EIS document. In addition to the proposed action, staff will consider a no-action alternative. We are also considering an alternative to the proposed actions that potentially meets the above criteria: GLHA's proposed action for each project with staff modifications, including any mandatory conditions ( i.e., the staff alternative with mandatory conditions).

With this notice, we ask commenters to identify other potential reasonable alternatives for consideration. The alternatives considered may be expanded based on the comments received, provided they meet the criteria described above.

Schedule for Environmental Review

This Notice of Intent identifies Commission staff's planned schedule for completion of the final EIS for the projects, which is based on an issuance of a draft EIS in July 2027, opening a 45-day public comment period. All comments filed will be reviewed by staff and considered in the Commission's final decision on the proceedings.

Issuance of Notice of Availability of the final EIS March 31, 2028

If a schedule change becomes necessary, an additional notice will be provided so that the relevant agencies and interested stakeholders are kept informed of the project's progress.

Permits and Authorizations

The table below lists the anticipated permits and authorizations for the projects required under federal law. This list may not be all-inclusive and does not preclude any permit or authorization if it is not listed here. Agencies with jurisdiction by law and/or special expertise may formally cooperate in the preparation of the Commission's EIS and may adopt the EIS to satisfy its NEPA responsibilities related to the projects.

Additional Information

Additional information about the projects is available on the FERC website at www.ferc.gov, using the eLibrary link. Click on the eLibrary link, click on “General Search” and enter the Docket No. P-2458 or P-2572, as appropriate, in the “Docket Number” field. Be sure you have selected an appropriate date range. For assistance, please contact FERC Online Support at FercOnlineSupport@ferc.gov, or (866) 208-3676 (toll free), or (202) 502-8659 (TTY).

Any questions regarding this notice may be directed to Kristine Sillett, the FERC relicensing coordinator for the Penobscot Mills and Ripogenus Projects, at (202) 502-6575, or kristine.sillett@ferc.gov.

(Authority: 18 CFR 2.1)