Few signs of damage are visible just over a year after a powerful explosion at a Plymouth liquified natural gas tank farm.
Marks still are visible on a pressure vessel that erupted and on one of two 90-foot-tall tanks at the Williams Northwest Pipeline facility in southern Benton County.
But there is little sign of an equipment building that was damaged. The company demolished and removed it, and a new building will be built soon, district manager Von Studer said.
“This is the primary area where most of the damage occurred,” Studer said during a media tour Friday.
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The plant has been fixed up, though it is largely the same facility it was before the explosion, said Tom Clouse, coordinator of maintenance at the facility.
“All of this was already here,” he said. “All the other buildings were the same buildings; they were just repaired.”
A pump for the pipeline can be heard, and there are other signs of the plant coming back to life, though it isn’t expected to be fully operational until April 2016.
Tank 1, where a leak occurred after it was hit by shrapnel from the pressure vessel explosion, has been repaired. Williams hopes to start putting natural gas back in it this fall, Studer said.
The repairs to the 14.6 million-gallon tank are part of a $69 million project to get the plant operational again.
No damage occurred at the plant’s other tank.
The towering pressure vessel where the explosion happened also is under repair.
The March 31, 2014, explosion near the Columbia River could be heard from 20 miles away, and caused a fire that damaged several buildings on the 80-acre property.
One man was transported to Portland to be treated for burns to his face and hands, while four other employees were locally treated for injuries and released.
The plant has about 20 employees, which is nearly fully staffed. Studer said they are working with engineers, safety personnel and the state Utilities and Transportation Commission to get the plant back online.
The employees are reviewing the plant’s procedures and learning about the new equipment being installed, Studer said. There is a key message they are giving the workers.
“Safety is the most important thing,” he said. “They have the authority and the expectation to say something if they see something that is not safe.”
The accident happened while Williams was readying the two tanks after the 2013-14 heating season, according to an update from Williams. An inadequate purge of natural gas into the system resulted in an explosive mixture of gas and air with an ignition source that led to the failure.
The company has revised and improved its purge procedures and trained operations personnel, Williams said. It followed its existing procedures “precisely,” but lacked needed details to provide an adequate process for all operating conditions.
Federal officials plan to release a report with the cause of the blast this summer, after coming to talk to residents of the community of about 300.
Much of Plymouth was at the plant Friday evening to eat a barbecue meal provided by Williams and hear about the progress at the facility.
“We told them we would have an event to share some of our findings,” Studer said. “We decided to do a barbecue and tie that in with the update.”