A report released by the Forest Service recommends that the aging structure be torn down. The dam holds back toxins from decades of mining up stream, and as well as acknowledging that the river needs an environmental clean-up, Baucus is concerned that the weakening structure could fail – as it did 31 years ago.

The Senator said that whilst he is in favour of removing the dam altogether, he would listen to any alternatives offered by the Forest Service. One such option would be to partially remove it and re-route Beartrap creek, which feeds the pool behind the dam.

He also requested that the public comment period, where members of the community can have their say on how the polluted site is dealt with, be extended beyond its current 16 August deadline.

Mike Horse dam was built in 1941 and was declared unsafe last August following a final report from the Forest Service.