(credit: CBS)

PARACHUTE, Colo. (AP) — Crews are working to contain and clean up an underground oil spill that has contaminated around 1,400 barrels of groundwater in western Colorado.

The state Department of Natural Resources said 129 barrels of natural gas liquids had been recovered as of Monday morning. The spill covers a 200-by-170 foot area and is about 60 feet from Parachute Creek.

Officials say there are no signs the creek has been affected. Containment booms have been placed around the creek, and crews are checking the water every half hour.

The leak was discovered March 8, but the cause isn’t known.

The Denver Post reported that Williams Energy told state regulators that “hydroexcavation work was being done” in a pipeline corridor when crews found discolored soil.

A headgate used to divert creek water into the town reservoir has been closed, The Denver Post reported. “We haven’t opened that up and obviously won’t until we have this figured out. We don’t want to have any contamination,” town administrator Bob Knight said.

The town of Parachute has around 1,100 people.

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