Environmental Impact Statement Developing Proposal

Stillwater Mine Complex Amendment 14 EIS

Custer Gallatin National Forest Stillwater, Montana Custer Gallatin National Forest All Units

The Stillwater Mine Plan of Operations amendment proposes to continue production of platinum group metals via underground mining operations for an additional 36-42 years through the expansion of existing surface infrastructure and construction.

Location

The project is located within the Stillwater River drainage near Nye, Montana, involving both private and National Forest System lands.

Project timeline

1
NOI in Federal Register
06/2026 (Estimated)
2
DEIS NOA in Federal Register
06/2027 (Estimated)
3
FEIS NOA in Federal Register
04/2028 (Estimated)
4
Objection Period Start
01/2028 (Estimated)
5
Decision
04/2028 (Estimated)
6
Implementation
06/2028 (Estimated)

NEPA / regulatory detail

Special AuthorityNot Applicable / Other
Notice and Comment Regulation218 (2013) Non-HFRA
Project ActivityMinerals Or Geology Plans Of Operations
ForestsCuster Gallatin National Forest
DistrictsBeartooth Ranger District
Legal Land DescriptionNot Applicable
Minerals and geology