Conway gas spill site cleanup continues

CONWAY — Last week’s weather paused cleanup operations of the December Olympic Pipeline gasoline spill east of Conway. By Jan. 20 excavation of impacted soil at the spill site north of SR 534 resumed. This update is from United Command press releases.

SR 534 will be closed in both directions at the site in the near future for a period of four to six hours while a temporary sheet piling wall is installed to isolate the eastern bank of Hill Ditch and allow response crews to dig out the remaining impacted soil and sediment and replace it with clean soil. At press time a date had not been set. Closures will avoid peak commuting or school pick-up or drop-off times.

The wall will be installed along approximately 220 feet of the impacted east shoreline, just north of SR 534. Large interlocking steel sheet pilings will be installed using a crane-mounted vibratory pile-driving system.

Pile driving operations are expected to begin in early February and last approximately two weeks. The pile driving system will operate during daylight hours. There will be elevated construction noise and vibration in the immediate area. Vibration and noise monitoring will be in place along the Hill Ditch dike and along the pipeline.

Water sampling has not found any exceedances of environmental or health-based screening values for at any location since Dec. 22, 2023 from nearby waterways including Hill Ditch, Skagit River, and Skagit Bay.

No public health risk from gasoline fumes have been detected from air field sampling and laboratory analyses. Community air monitoring will continue during work hours when impacted soil is being removed.

Removal of some of the boom downstream of the I-5 overpass was to be removed last week since there has been an absence of detectable hydrocarbons in Hill Ditch below the SR 534 bridge.

Approximately 25,326 gallons of gasoline leaked and some 8,325 gallons recovered through Dec. 29.

The Unified Command consists of the U.S. Environmental Protection Agency, the Washington Department of Ecology, Skagit County Department of Emergency Management, bp and the Swinomish Indian Tribal Community.

Status updates are posted on the Department of Ecology’s website: https://ecology.wa.gov/spills-cleanup/spills/spill-preparedness-response/responding-to-spill-incidents/spill-incidents/olympic-pipeline-gasoline-spill-mt-vernon