Columbia Falls may know by autumn whether the now-closed aluminum smelter there will become a Superfund site.
Last Tuesday the owners of the Columbia Falls Aluminum Company announced the smelter is permanently closing.
The next day the Environmental Protection Agency notified Governor Steve Bullock it proposes to add the plant to its priority list of industrial sites that should be cleaned.
"Investigation has shown that there are contaminants that potentially could impact human health and the environment at the site. A listing on the National Priorities List identifies sites where additional information is needed" said EPA's Cynthia Peterson.
Smelter officials oppose a Superfund listing, describing it as slow and stigmatizing.
EPA say the Priorities list proposal will be added to the Federal Registry by the end of March, followed by a 60-day public comment period. A final decision could be issued by this fall.