Lepore: Gradient protecting creek from leak
The elevation of the water table below Parachute Creek is higher than at the site of a nearby hydrocarbon leak, helping protect the creek from contamination, the director of the Colorado Oil and Gas Conservation Commission said Wednesday.
“So the groundwater flow direction should be away from the creek. Put it differently, to get to the creek the contamination would have to go uphill,” Matt Lepore said in an interview.
An investigation into a leak of an unidentified liquid hydrocarbon in a pipeline corridor near the creek northwest of Parachute continues to focus on a valve box associated with a Williams natural gas liquids line coming from its nearby gas processing plant. A 30-inch-diameter gas pipeline leading to the plant also is being excavated and inspected in a process that Lepore said can’t be rushed.
Todd Hartman, a spokesman for the state Department of Natural Resources, said Wednesday that results of water samples taken by the COGCC show no signs of contamination in the creek.
Bob Arrington, a retired engineer in Battlement Mesa who is active with the Western Colorado Congress and Battlement Concerned Citizens groups, questions how groundwater wouldn’t go into a stream located at the center of a valley.
“That groundwater is seeking its way to the stream and it’s got more head (pressure) coming off the hillsides than the stream (groundwater) going up the hillsides,” he said. ” ... The whole flow profile is just going to slowly pour into that gully and go down to the (Colorado) River.”
A monitoring well has found liquid hydrocarbons on the surface of groundwater 30 feet from the creek, between the creek and a trench dug to try to intercept the contaminants. Lepore said the trench appears to be creating a vacuum pressure that draws groundwater toward it.
On Tuesday, the Grand Valley Citizens Alliance called on authorities from the COGCC and other government agencies to be more forthcoming regarding information related to the spill, saying a lack of transparency has raised fears that the extent of environmental damage is being kept hidden.
Lepore the investigation is ongoing and “very dynamic,” but the COGCC has talked about what’s being done to identify the source, about the “hot spot” at the valve box, and about monitoring wells and other developments.
“Can we do more, better, faster all the time? Always, yeah, but I’m not quite sure what we’re withholding or are perceived to be withholding,” he said.