The Bristol Bay watershed in southwestern Alaska supports the largest sockeye salmon fishery in the world, is home to 25 federally recognized tribal governments, and contains large mineral resources. Learn more about Bristol Bay.
On January 30, 2023, EPA issued a Final Determination under its Clean Water Act Section 404(c) authority to help protect the most productive wild salmon ecosystem in the world. With this action, EPA is limiting the disposal of dredged and fill material associated with developing the Pebble deposit in certain waters that are important to sustaining the region’s salmon resources.
After reviewing the Recommended Determination provided by Region 10, including the scientific and technical information spanning nearly two decades, EPA has determined that the discharges evaluated in the Final Determination will have unacceptable adverse effects on salmon fishery areas in the South Fork Koktuli River, North Fork Koktuli River, and Upper Talarik Creek watersheds of Bristol Bay.
The Final Determination prohibits the specification of certain “waters of the United States” in the South Fork Koktuli River and North Fork Koktuli River watersheds as disposal sites for the discharge of dredged or fill material for the construction and routine operation of the mine plan described in Pebble Limited Partnership’s June 8, 2020, Clean Water Act Section 404 Permit application, as well as future proposals to construct and operate a mine to develop the Pebble deposit that would result in the same or greater levels of loss or change to aquatic resources.
The Final Determination also restricts the use of certain “waters of the United States” in the South Fork Koktuli River, North Fork Koktuli River, and Upper Talarik Creek watersheds as disposal sites for the discharge of dredged or fill material associated with future proposals to develop the Pebble deposit that would result in adverse effects similar or greater in nature and magnitude to those associated with the Pebble Limited Partnership’s 2020 Mine Plan.
For previous announcements, see Bristol Bay 404(c) timeline.