The U.S. Army Corps of Engineers notified Coeur Alaska and Goldbelt on Tuesday it has suspended their water discharge permits related to the Kensington Mine.
Coeur Alaska, developer of the mine, must stop building structures or discharging fill material into wetlands or waterways during the permit suspension, according to the Corps of Engineers.
Any work related to Goldbelt's discharge permit at Cascade Point in Berners Bay also must immediately cease.
"I have determined that the public interest requires this suspension in order to revisit, reconsider and clarify the Record of Decision for the permit and (its) underlying analysis," wrote Col. Timothy Gallagher, the district engineer for Alaska, in his letter to Coeur Alaska on Tuesday.
Gallagher cited the same basic purpose for suspending the Goldbelt permit, which allows construction of a ferry terminal to carry mine workers.
Coeur Alaska will be allowed to conduct any work needed to prevent potential harm from its construction, and to ensure compliance with water standards, Gallagher wrote.
But he warned Coeur Alaska that if it built any facilities on previously authorized fill material, the company would be taking a risk. "The Corps may determine as a result of our review that such facilities must be removed or remediated," Gallagher said.
In the next 10 days, both Goldbelt and Coeur Alaska can request a private meeting or a public hearing to discuss the suspension of their permits.
After revisiting the permits, Gallagher said he will either "reinstate, modify or revoke" them.