DENVER (AP) — The gas company that found loose hydrocarbons near Parachute Creek in western Colorado says a failed pressure gauge was the source of the gas liquids.

Hydrocarbons, including the carcinogen benzene, were discovered in soil and groundwater near the Williams natural gas processing plant in Parachute in early March.

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Williams said Wednesday the source of the hydrocarbons is a pressure gauge that failed in December. It says the leak started Dec. 20 and was stopped Jan. 3. At that time, crews were unaware just how much had seeped out.

The contamination was rediscovered in March as workers were excavating the area.

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Williams estimates more than 10,000 gallons of natural gas liquids leaked from the pressure gauge. About 6,000 gallons have been recovered.

Williams says the contamination didn’t reach Parachute Creek.

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