Williams to replace Parachute pipeline
Williams is planning to replace a natural gas liquids pipeline involved in a leak that contaminated Parachute Creek several years ago, after a U.S. Department of Transportation decision that it has regulatory authority over the line.
The company is planning to install a 2,000-foot-long, 6-inch-diameter line that will travel through a 400-foot, horizontally drilled bore about 17 or 18 feet beneath Parachute Creek. The line, about 4 miles northwest of Parachute, will connect Williams’ nearby gas processing plant with a tank farm, after which the liquids are shipped by another pipeline to another processing plant in Rio Blanco County.
Another pipeline now crosses under the creek, part of it 4 inches in diameter, and part of it 6 inches. In early 2013, the company discovered a natural gas liquids leak associated with the pipeline, which it pinpointed not to the pipeline itself but to an attached, above-ground pressure gauge that had broken.
Williams estimated that about 50,000 gallons had leaked, with about 40,000 gallons vaporizing and about 10,000 gallons reaching the ground. High levels of benzene, a carcinogen, were found in groundwater. Benzene levels that briefly exceeded the designated safe drinking water standard were found in the creek, but the benzene didn’t travel far downstream and the creek soon was declared benzene-free.
A soil and groundwater cleanup program that is ongoing has resulted in thousands of gallons of natural gas liquids being recovered.
At the time, the Department of Transportation’s Pipeline and Hazardous Materials Safety Administration didn’t regulate the pipeline beneath the creek. Instead, it assumed jurisdiction beginning with the pipeline shipping the natural gas liquids from the tank farm.
Diana Anderson, Williams’ project manager for the new pipeline, said that following communications between the safety administration and Williams after the leak, the agency determined that its authority extends to the pipeline running from the plant and beneath the creek.
Williams could have gone through a process for converting the pipeline for service as a federally regulated line, but that involves a verification process, with steps including running what Anderson called a smart tool through the line to check its condition. She said that’s particularly difficult for a dual-diameter line, and the verification work also could have required some digging in the area of the pipeline, which the company wanted to avoid while reclamation work following the leak is still going on there. So it ultimately decided that replacing the pipe made more sense, and might end up being cheaper.
The company hopes to begin the project this year. It has obtained a state stormwater permit and also needs a permit from Garfield County. On Thursday, the Parachute Town Council approved a watershed permit for the project under a process designed to protect the town’s water supply. But council members first asked several questions of Williams representatives in an attempt to obtain some reassurance about the project, with Mayor Roy McClung explaining to them that the leak “caused quite a ruckus.”
He said the incident resulted in internet blogs that were “very anti-industry.”
“In fact they were so bad they were even anti-Parachute for a while regarding the way that was handled. So we’ve got a heightened sensitivity,” he said.
He said he recognized that Williams is trying to follow best practices.
“We also need to make sure that we’re covering everything from our end and our constituents’ end as well,” he said.
Anderson said the new pipeline, like the current one, will have a leak detection system. But as a DOT-regulated line, that system will be linked to Williams pipeline control personnel in its Tulsa headquarters, providing for even more stringent real-time monitoring, she said.
She said that while there are no indications of problems with the current line, the new one will represent an upgrade.