Work to clean up two contaminated ponds bordering the Flathead River at the Columbia Falls Aluminum Company Superfund site was completed earlier this month.
CFAC announced the cleanup and removal of the two percolation ponds at the now defunct aluminum smelter in a press release. Work wrapped up on March 19. The removal of the ponds means the Flathead River returns to its natural channel.
Leading up to the cleanup, the earthen dams that prevent the ponds' contaminants from washing into the river were eroding. The U.S. Environmental Protection Agency last year approved the cleanup and removal of the ponds ahead of schedule because of the erosion.
The draft feasibility study for cleanup work on the remainder of the Superfund site will be complete May 31. The EPA will assess the cleanup options in that plan before it issues a final decision on what that process will look like. That decision isn’t expected until mid-2022.