The Environmental Protection Agency is asking the Army Corps of Engineers to not immediately re-issue a permit for Kensington gold mine in Alaska, despite a Supreme Court ruling last month that upheld the now-expired permit.

In a letter to the Corps—and to the consternation of mine owner, Coeur d’Alene Mines Corporation—the EPA argued that a dry lands disposal plan favored by environmental groups is feasible and better for the environment. EPA estimates it would take 8 months to review and approve the plan, whereas Coeur wants to immediately start working on the mine.

The EPA said its request was based on new developments—including acid drainage from the mine site—since the original permit was issued in 2006. The Corps could reject EPA’s recommendation and reissue a permit for lake-dumping, but EPA has the ultimate power of veto.

The Supreme Court said Kensington’s plan to dump mine tailings in Lower Slate Lake was legal under Bush-era provisions written into the Clean Water Act. The tailings would kill all the lake’s fish. Environmental groups represented by Earthjustice won a series of lower court victories to prevent the dumping plan.