The U.S. Army Corps of Engineers, Alaska District, has issued a permit to Teck Resources Ltd. subsidiary, Teck Alaska Inc., to develop a new open pit at the Red Dog zinc mine in Northwest Alaska. In operation since 1989, ore at the zinc-lead mine’s existing open-pit is expected to be depleted by next year.
Issued under Section 404 of the Clean Water Act, the permit authorizes Teck Alaska to develop a new pit, named Aqqaluk, adjacent to the mine’s existing pit. Sized to minimize impacts to wetlands, the new pit will measure 600 feet, or 182 meters, deep and up to 0.75 miles, or 1.2 kilometers, in diameter. The Corps said the development of Aqqaluk will disturb 119 acres of moderate value wetlands. The project would also impact 126 acres of uplands that the Corps does not have jurisdiction over.
The Corps permit authorizes discharges of fill material into wetlands for constructing auxiliary structures such as temporary stockpiles, access roads, and diversion channels. Access roads and diversion structures will be located within the pit boundary and waste rock will be deposited in the existing pit to minimize environmental impacts.
A permanent diversion structure, or similarly functioning temporary structures, will be constructed for Sulfur Creek prior to developing the pit within the Sulfur Creek drainage basin. The purpose of the structure is to divert clean water around the pit, thereby minimizing the volume of water that contacts mineralized materials and limiting the volume of water requiring treatment.
In order to compensate for unavoidable impacts, Teck Alaska has agreed to pay an in-lieu fee to the Conservation Fund to mitigate at a ratio of 2-to-1 for the loss of wetlands in accordance with the Conservation Fund’s Memorandum of Agreement with the Corps’ Alaska District.
