PARACHUTE, Colo. (AP) - Samples taken from monitoring wells near an oil-like leak close to a Williams Midstream natural gas plant show high benzene levels near Parachute Creek.

But Williams and state officials say there's no evidence of contamination in Parachute Creek, which flows into the Colorado River.

Colorado Department of Natural Resources spokesman Todd Hartman said Thursday the wells showed benzene levels of 5,800 to 18,000 parts per billion. That's far above the state health standard of 5 parts per billion.

More monitoring wells will be drilled about 10 feet from the creek to get more details on groundwater impacts.

Company workers looking for the source of the leak are focusing on a valve box for a pipeline carrying natural gas liquids away from the natural gas plant.