The East Boulder Mine, which is located near Big Timber, Montana, is one of only two mines where platinum and palladium are actively mined in the U.S. These designated critical minerals are used in the manufacturing of catalytic converters, which limit harmful exhaust emissions from gasoline-powered vehicles; recently, these minerals have also been used in battery-electric vehicles and fuel cell technologies. The East Boulder Mine has been operating since 2001 but is running out of storage for mine tailings and waste rock (materials left over after mining and milling of ore). The mine operator, Stillwater Mining Company (SMC), a subsidiary of the South African company Sibanye-Stillwater, has applied to the CGNF, Yellowstone Ranger District (Forest Service), and the Montana DEQ for a fourth amendment to the East Boulder Mine Plan of Operations and State Operating Permit that would allow SMC to construct a new tailings storage facility and a new waste rock storage area to provide 11 to 14 years of storage.
In compliance with NEPA and MEPA, the Forest Service and DEQ, respectively, must complete a joint Environmental Impact Statement (EIS) to evaluate the potential impacts of their decisions regarding SMC’s amendment request. ERO is the third-party contractor that was selected by the two agencies to prepare the EIS and supporting documentation. The agencies returned to ERO after we successfully assisted them with another joint environmental review process for this mine in 2020 (see write-up below for Project # 10503).
Over the last two years, ERO has helped the agencies navigate the often-complicated joint environmental review process, which involves both state and federal requirements. To kick off the process, ERO facilitated a public scoping process (June–July 2022) and public meetings (virtual and in-person in Big Timber, Montana), helping the agencies categorize and address public concerns about the project and identify suggested alternatives and mitigations raised in public comments. ERO, with support from our team of subcontractors, also helped the agencies develop alternatives to the proposed project. We prepared a number of supporting analytical reports, including three technical memorandums and eight specialist reports and/or biological evaluations that analyzed anticipated impacts of the proposed project (and alternatives) on key natural resources.
Based on scoping issues and supporting reports, ERO prepared a Draft EIS, which was issued by the agencies for a public comment period in June 2023. ERO ensured a smooth roll-out of the Draft EIS and helped the agencies prepare and issue public notices about the comment period. ERO facilitated public involvement, helping the agencies host another public meeting (virtual and in-person in Big Timber, Montana) and leading an efficient process to categorize and respond to public comments on the Draft EIS. After revising the EIS to respond to public comments (including adjustments to one of the alternatives), ERO worked with the agencies to prepare a Final EIS and a Draft Forest Service Record of Decision (ROD) for the Forest Service’s Pre-Decisional Administrative Review process (objections process). The Forest Service issued the documents for a 45-day objection period in November 2023. No objections were received, and ERO is currently helping the agencies prepare the joint Final EIS and their respective RODs. The Final EIS is anticipated to be issued in August 2024, followed by the RODs in September 2024.
