An agency report also found that "underestimation of the water pressure" in the mine was likely the most significant factor relating to the blowout.
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It's a reversal for local officials who long feared that designation as a federal Superfund site would harm economic development.
Colorado must reduce its carbon emissions levels by 40 percent. It's well on its way.
A 2013 report says taxpayers should be getting more money from federal coal extraction fees. Local governments say changing the fees will cripple the industry.
Lawmakers passed a bill in 2013 allowing for graywater use in Colorado, but the practice has gone virtually nowhere.
While the EPA and its contractors triggered the Gold King blowout, the agency is far from the only party responsible for the accident.
New Mexico officials on Saturday lifted the ban on using the Animas and the San Juan rivers for drinking water after a major wastewater spill in Colorado.
But there’s still no information on the orange sediment that the toxic plume laced with heavy metals has left in the riverbed and on the banks.
"The levels of the toxic metals that are in the water are now low enough, says Ron Hewitt Cohen, a mine cleanup expert.
State attorneys general say they’ll be watching the effects to ensure that land is restored and residents are compensated damages.
Colorado's chief medical officer said preliminary water test results look promising. The EPA isn’t ready to draw any conclusions.
Water samples taken after the spill showed lead concentrations in some places that were 3,500 times the normal levels.
The majority of Americans favor government action, but the candidates — and big donors — differ greatly. Here is what they've said on the topic, beginning with whether climate change is real.
In the meantime, state agencies are helping the EPA determine the environmental and health impacts of the accident.