The US$22M project, which consists of a retention reservoir to collect the contaminated runoff from Slickrock Creek and run it through a treatment plant, is expected to be finished late next year.

The project follows last year’s nearly $1 billion settlement reached by state and federal negotiators and the owner of the mine, Aventis CropSciences US, to cleanup the site – a source of toxic metals in the country.

As part of the settlement, a dam is to be built on Slickrock Creek that will collect toxic mine drainage and send it to the site’s wastewater treatment plant, which was constructed in 1994. Clean water upstream from the mountain, meanwhile, will be diverted around the contaminated section.