Donlin Gold Mine NEPA EIS

Crooked Creek, Alaska

Kuskokwim River

Credit: Joseph—Cabin on the Road

The largest gold mine project under development in Alaska in many years has been proposed by Donlin Gold, LLC. The reserves for this open pit, hard-rock gold mine are located in southwest Alaska about 277 miles west of Anchorage in the Kuskokwim River’s Crooked Creek drainage. The project would require about 3-4 years to construct, have a mine life of about 27.5 years, and produce an estimated one million ounces of gold annually. Besides the mine, key project features include:

  • A 315-mile natural gas pipeline from Cook Inlet to the mine
  • New port facilities on Cook Inlet and the Kuskokwim River
  • A 5,000-foot airstrip
  • A tailings storage facility involving a 464-foot high dam and 2,351-acre impoundment
  • Other transportation, mining, water and fuel storage, water treatment, and housing infrastructure to support mine construction, operations, closure, and reclamation

As a key member of a third-party consultant team under contract with the U.S. Army Corps of Engineers for a NEPA EIS, Hart Crowser served as subject matter expert for fisheries and aquatic resources. We evaluated:

  • Habitat use and distribution of salmon and resident fish in drainages traversed by the proposed mine, gas pipeline, roadways and airstrips, port sites, and other mine infrastructure between Cook Inlet and the Bering Sea
  • Potential impacts of mine dewatering on instream flows and temperatures on salmon and other fish populations in the Kuskokwim River and Crooked Creek drainage
  • Effects of port development and barge-generated propeller wash and waves on fish habitat, riverbed scour, wave generation, bank erosion, and potential fish injury and stranding
  • Potential impacts from low probability but potentially high consequence events that could result from releases of hazardous waste, fuel, or potential failure of the proposed tailings dam with up to 568-million-tons of mine tailings capacity