Colorado oil and gas companies used toxic chemicals prohibited under state law in operations involving dozens of wells on either side of the Rocky Mountains over at least the last 18 months, a Capital & Main investigation found.
Disclosures to the state’s fossil fuel regulator showed operators combined banned substances with water, sand and other chemicals as part of a process known as hydraulic fracturing, or “fracking.” Companies pump this mixture down a well extending thousands of feet underground to crack shale and release oil and gas.
