Olympic Pipeline Spill Conway

Facility Site ID: 100001019 Cleanup Site ID: 17006

Last updated: 7/23/24

The emergency response phase ended on 3/24/24. The Toxics Cleanup Program (TCP) is in the process of conducting an Initial Investigation, which will be completed by the end of August 2024. At the same time, BP is in the process of cleaning up impacted soil. When we finish the Initial Investigation, TCP will determine if the site continues to pose a threat to human health and the environment.

Site Discovery

Aerial figure of spill location.
Aerial figure of spill location.
Where is the site located?
The site is located north of SR 534 and northwest of Conway Elementary School.

When and why did the contamination happen?
A gasoline spill occurred at the Olympic Pipeline near Conway on December 10, 2023. A Unified Command consisting of Ecology, the U.S. Environmental Protection Agency, the Swinomish Indian Tribal Community, the Lummi Nation, Skagit Department of Emergency Management, and BP was promptly formed, and containment efforts began. The Unified Command determined that the leak was caused by the failure of 3/8 inch tubing inside a concrete vault (MP 46 Block Valve) that connected one of the pipelines to a pressure sensor. The pipeline leak was stopped on December 10. Emergency response (cleanup of gasoline from water and ground surfaces) and surveys of impacted areas were carried out by the Unified Command from December 10, 2023, through March 24, 2024, during which status updates were routinely released on Ecology's Spill Incidents Page. Now that the emergency response concludes, the lead Ecology program has transition to the Toxics Cleanup Program (TCP).

Washington State Cleanup Law - Model Toxics Control Act

The Model Toxics Control Act (MTCA) is Washington’s environmental cleanup law. It provides requirements for contaminated site cleanup and sets standards that protect human health and the environment. Ecology enacts MTCA and oversees cleanups. A site is defined by the boundaries of where contamination from a specific source has ended up. A site may include part of a property, a whole property, or multiple properties.
Graphic of MTCA cleanup stages.
Graphic of MTCA cleanup stages.

Initial Investigation

When Ecology learns about a release of a hazardous substance into the environment, we do an Initial Investigation. Release information may come to us through the Environmental Report Tracking System, either from the property owner making a required notification or as a complaint from someone who saw the release.

During the Initial Investigation, we evaluate environmental conditions at the property and review all available data. The goal of the Investigation is to determine if the release may pose a threat to human health or the environment, and if further cleanup actions are needed. We track any site that is suspected or confirmed to be contaminated with hazardous materials, as required by MTCA.
Note: information on this site is considered accurate at the time of posting but is subject to change as new information becomes available.
No documents found.
There may be more documents related to this site. To obtain documents not available electronically, you will need to make a public records request.

Places to see print documents

  • Northwest Regional Office
    15700 Dayton Ave N
    Shoreline, 98133
    Please schedule an appointment to view print documents at this location.

Contaminants 3

Contaminant Type
Surface Water
Non-Halogenated Organics - Benzene C
Non-Halogenated Organics - Other Non-Halogenated Organics C
Non-Halogenated Organics - Petroleum-Gasoline C
Confirmed Above Cleanup Levels
Below Cleanup Levels
This contaminant list was based on our best information at the time it was entered. It may not reflect current conditions at the site.