Gold King Mine

Alexco Environmental Group (AEG) has started operation of an interim water treatment facility at the Gold King Mine near Silverton, Colorado, under contract to the US Environmental Protection Agency (EPA).

The contract awarded to AEG to design, construct and automate the mine’s 1,200g per minute (gpm) water treatment plant is part of the emergency response and removal action being conducted by the agency.

AEG will act under supervision from Environmental Restoration (ER).

The mine was the site of a spill that flooded the Animas River in southern Colorado in August.

On 5 August, the EPA workers accidentally triggered a breach at the mine in San Juan County during an investigation that was aimed at evaluating the ongoing water releases from the site and to treat mine water.

The new plant is set to address water treatment residuals during cold weather operations.

"The new plant is set to address water treatment residuals during cold weather operations."

According to AEG, the plant will be further optimised and winterised for the harsh conditions expected at 10,500ft in the San Juan Mountains of southern Colorado.

With flexibility to use diverse sources of low-cost alkalinity, the treatment plant is currently operating under complete automation in the 600gpm to 1,200gpm range.

AEG business and strategic development vice-president Joe Harrington said: "We are pleased with our rapid construction response and successful initial operation of our plant near the Gold King Mine; we are also mindful that this was a superior effort by our engineers, scientists, employees and sub-contractors, all of whom deserve credit.

"At the end of the day, we are all proud to be a small part of the beginning of environmental improvement of the upper reaches of the Animas River in Colorado."

Image: Entrance to Gold King Mine, Colorado. Photo: courtesy of EPA.