Sunnyside Gold Corp. has been resisting attempts made by the Environmental Protection Agency to get the company to pitch in money for the cleanup.
Environmentalists say cities and counties shouldn’t be barred from action.
The documents may have evidence of residual plutonium contamination and other ongoing environmental dangers.
A new study from the Environmental Protection Agency found fish and other aquatic life in the are are not suffering severe or long-lasting damage.
The wildlife refuge's past as a Superfund site has caused concern among environmental groups.
The 2015 spill sent a yellow-orange plume of toxic heavy metals into rivers in Colorado, New Mexico, Utah and on Native American lands.
A retired professor claims he has evidence of plutonium particles contaminating the refuge. Government lawyers counter that the EPA has since determined the area was safe.
Research from atmospheric scientists in Boulder finds that personal care products can create emissions off your body at a level on par with your car’s tailpipe.
Colorado's top regulator says as long as the rules are followed, “there’s very little risk, very little potential harm of having empty, abandoned, plugged, capped lines in the subsurface.”
Firefighting foam used at the base for decades seeped into the aquifer, rendering well water for customers in southern El Paso County unsafe to drink.