The Environmental Protection Agency began soliciting bids for a temporary water treatment plant roughly two weeks after the Gold King Mine blew out in early August, documents released Tuesday show.
The agency required the plant be fully operational within three weeks of the contract being awarded, according to an Aug. 21 request for proposal from EPA contractor Environmental Restoration LLC.
“This is an emergency response action,” the proposal request said.
The EPA released roughly 150 pages of new documents linked to the Gold King spill’s aftermath on Tuesday, as well as eight videos of workers explaining what led up to the 3 million-gallon wastewater spill.
The EPA told The Denver Post on Tuesday that it has still not decided if it will build a water treatment plant below the Gold King, where the agency accidentally triggered the spill Aug. 5. Nancy Grantham, an EPA spokeswoman, said the agency has received six bids and is evaluating each one.
“The treatment plant is a contingency option,” Grantham said. “The agency continues to evaluate data to determine the impacts of the Gold King Mine on water quality currently and going into the winter months.”
Grantham said the Gold King “is one of many mines contributing to poor water quality in the Animas” and treating its waste “may or may not have a measurable impact downstream going forward. ”
The EPA estimates it will cost $3 million to implement and run for a year a treatment apparatus if one is erected. The EPA says the system will be temporary.
“The system must be able to be operated all year at an elevation of approximately 10,500 (feet),” the proposal request from Environmental Restoration said. “Extreme cold and heavy snow are to be expected and planned for. The system must be self-contained as there are no amenities on site.”
The EPA tasked Environmental Restoration with finding a subcontractor to construct the plant.
The request says the EPA hopes the plant will render mine discharge “neutral” through the removal of dissolved and total solids and metals. Once the plant is operational, the request says, the current onsite treatment — five settling ponds, will be suspended.
Experts say that while a treatment plant at the mine would be expensive and difficult to maintain, it would be the best option.
“That’s definitely the trade-off,” said Mary Boardman, a Colorado Division of Public Health and Environment project manager. “It is expensive to run, but it’s also the most effective (option).”
The mine continues to leach about 550 gallons of wastewater per minute.