DENVER (AP) – State officials say liquid hydrocarbons that have been seeping into the ground at a western Colorado gas field have affected a larger area than initially believed.

Energy workers discovered contaminated soil and groundwater about a month ago near the Williams gas processing facility in Parachute. Liquid hydrocarbons, including cancer-causing benzene, were discovered within 10 feet of Parachute Creek, which runs into the Colorado River.

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A spokesman for the state Department of Natural Resources said Monday that tainted soil and groundwater has also been found on the south side of the creek, opposite the bank where the seep was initially discovered.

Officials insist the creek remains unaffected, though protective booms placed across the water revealed the presence of hydrocarbons known as diesel range organics. No benzene has been found in the water, and officials say it is not clear whether the underground leak is the source of the hydrocarbons in the creek.

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(credit: CBS)

(credit: CBS)

The origin of the seep has not been pinpointed, though investigators are focusing on a 4-inch pipeline that carries natural gas liquids away from the processing plant.

More than 5,900 gallons of loose liquid hydrocarbons and 180,000 gallons of contaminated groundwater have been vacuumed up since the leak was first discovered by Williams employees. Workers noticed the problem as they were evaluating the area to prepare for the installation of a new pipeline.

The Colorado Oil and Gas Conservation Commission, part of the Department of Natural Resources, and Williams Cos. hosted a public briefing and answered residents’ questions at a Garfield County Energy Advisory Board meeting last week.

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