Olympic Pipeline gasoline spill near Conway

(Information on this site is considered to be accurate at the time of posting, but is subject to change as new information becomes available.)

The Washington Dept. of Ecology, the U.S. Environmental Protection Agency, the Swinomish Indian Tribal Community, Skagit Dept. of Emergency Management, and BP are responding to a gasoline spill at the Olympic Pipeline near Conway.

The pipeline leak was stopped on Dec. 10. Emergency response (cleaning up gasoline from water and ground surfaces) and surveys of impacted areas is in progress. Remediation, including revegetation, to begin after completion of emergency response.

Visit our Flickr site for photos of the response. Video is available on our YouTube site.

Summary information

Date of incident:  December 10, 2023
Location:

Conway, WA (unincorporated Skagit County)

Type of incident: Gasoline
Map of Olympic Pipeline gasoline spill near Conway

Map showing the location of the Olympic Pipeline gasoline spill near Conway, WA.

Status updates

Friday, Feb. 23, 2024 -- 6:00 p.m.

This week, a dewatering system was installed to remove water from the soil inside the cofferdam. Water removed from the soil will be cleaned and returned to the environment. Excavation of contaminated soil along the streambank is expected to begin within the next few days, after testing of the dewatering and water treatment systems is complete. 

Surface water sampling will continue during excavation. 

Friday, Feb. 16, 2024 -- 4:15 p.m.

Cofferdam installation
The sheet pile cofferdam is installed, and fish exclusion nets are removed. Preparations for excavation are in progress with excavation likely beginning next week. A dewatering system will be installed to remove water from the soil inside the cofferdam. Water removed from the soil will be cleaned and returned to the environment. Contaminated soil will be excavated for disposal. 

Surface water sampling during excavation will continue.

Air monitoring and potential gas odor
During excavation, mild gasoline odor may be noticeable near the site. When excavation begins, enhanced air monitoring on the site will ensure the safety of response workers. Community air monitoring will continue to ensure protection of the public. Based on sampling data, we do not expect air sampling levels to exceed safety thresholds.

Friday, Feb. 9, 2024 -- 6:30 p.m.

Operational updates:

  • Construction of a sheet pile wall is underway to build a cofferdam, which will create a barrier between the water of Hill Ditch and the bank so the affected soils next to the ditch may be removed without impacting the water.
  • The sheet piling installation work will continue until it is completed, estimated to be February 15.  
  • The next step will be installation of the dewatering system, which is scheduled to begin by February 17. The dewatering system will remove water from the soil inside the cofferdam to ensure the stability of excavation and to maintain a safe working environment.  
  • Fish exclusion nets are in place to keep fish out of the cofferdam construction area. Crews are regularly checking the nets for fish that could be caught in the nets. The fish exclusion nets will be removed when the sheet wall installation is completed.
  • Turbidity curtains are in place to reduce loosened silt traveling downstream from the construction area.
  • Vibration caused by sheet pile installation operations is being measured and monitored to reduce the risk of potentially impacting homes or infrastructure in the immediate vicinity of the work. 
  • Visit our Flickr site for photos of crane and cofferdam work. Videos of aerial photography and wildlife field camera footage are available on our Youtube site.

Reporting sheens: The Unified Command asks members of the community and public to continue reporting sheens in Hill Ditch by emailing Liaison@ecy.wa.gov. To report sheens outside Hill Ditch, call 1-800-OILS-911.

Q&A from this week’s community events: At the February 6 open house and February 7 virtual meeting, Unified Command and subject matter experts heard and responded to questions from the community.

Wednesday, Feb. 7, 2024 -- 2:00 p.m.

Please join us this evening for a virtual meeting at 6 p.m. on Zoom. Additional information can be found at the link below. Ahead of this evening's meeting, you can read our Incident overview fact sheet (en espanol) and Response and cleanup fact sheet (en espanol). In addition, you can find new video related to the response on our YouTube channel: https://www.youtube.com/watch?v=JmiZRq0PrSE.

Wednesday, Feb. 7, virtual meeting

Wednesday, Jan. 31, 2024 -- 6:30 p.m.

TRAFFIC ADVISORY
Planned full closure of SR 534
Saturday, February 3, 2024 9:00 a.m. to approximately 1:00 p.m.

All lanes of State Route 534 near Conway Hill Road will close for approximately four hours to allow for delivery, offload and assembly of the crane required to install a sheet pile wall. Local access will be permitted for Conway Hill residents and residents nearest to the site. Through traffic will detour using Cedardale Road, Starbird Road, and Bulson Road.

Temporary sheet pile wall installation
Installation of the sheet pile wall is expected to begin next week. See update #17 for more information.

Biological sheens
Natural processes like bacteria or decomposition can create sheens on water that look similar to sheens caused by oil pollution. Learn more about biological sheens. Regardless of cause, the Unified Command asks members of the community and public to continue reporting sheens in Hill Ditch by emailing Liaison@ecy.wa.gov.

Friday, Jan. 26, 2024 -- 1:00 p.m.

The unified command is hosting two community meetings for the public to learn more about the gasoline spill, the status of the cleanup, air monitoring, water quality monitoring, wildlife impacts, and the plans and timeline for removing the remaining impacted soil and sediment. The in-person meeting will be on Tuesday, Feb. 6, from 5:30 – 7:30 p.m. The public is invited to drop in to the Open House anytime. There will be no formal presentation. The virtual meeting will be on Wednesday, Feb. 7, at 6 p.m. on Zoom. Additional information can be found at the links below.

Tuesday, Feb. 6, in-person meeting
Wednesday, Feb. 7, virtual meeting

Friday, Jan. 19, 2024 -- 5:00 p.m.

Cleanup progress and next steps
Field operations restarted this week following the January 12 weather stand down. Response teams have resumed excavation of impacted soil at the spill site.

In the coming weeks, response teams will begin installing a temporary sheet piling wall 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. This approach will allow responders to isolate contaminants from the ditch while minimizing disruption to any potential fish migration. 

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. Delivery and installation of the crane will require a full closure of SR 534 for a period of four to six hours. The date and times of the closure will be communicated to the public as soon as they are available. The closure will not happen during peak commuting or school pick-up or drop-off times.

Pile driving operations are expected to begin in early February and last approximately two weeks. The pile driving system will operate during daylight hours. Residents may notice 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
Ongoing sampling activities in the area have included collecting over 260 surface water and sediment samples in nearby waterways including Hill Ditch, Skagit River, and Skagit Bay. Sampling downstream of the spill site continues and no exceedances of environmental or health-based screening values for hydrocarbons have been reported at any location since December 22, 2023.

Air sampling
Over 7,000 real-time field readings and 132 lab analyzed air samples have been collected in the community, all of which continue to indicate no public health risk from gasoline fumes. Community air monitoring will continue during work hours when impacted soil is being removed.

Downstream booming
Because of the continued absence of detectable hydrocarbons in Hill Ditch below the SR 534 bridge, Unified Command has determined that some of the boom downstream of the I-5 overpass can be removed. The continued presence of the boom may inhibit the natural flow of water, fish, and wildlife. Boom removal may begin as soon as this weekend.

Thursday, Jan. 11, 2024 -- 10:00 a.m.

Due to inclement weather, the Unified Command is suspending active field operations beginning on Friday, Jan. 12. Regular operations are anticipated to restart on the morning of Tuesday, Jan. 16, weather permitting. This decision was made in the interest of personnel safety. Critical personnel will be on location 24/7 to monitor the response site and keep it secure. 

To date, air monitoring conducted at the direction of Unified Command has indicated no public health risk from gasoline fumes. The public may email liaison@ecy.wa.gov with any questions or concerns.

As of Jan. 10, 1,664 cubic yards of soil have been loaded onto trucks for treatment and disposal at a hazardous waste facility. Approximately 8,324 gallons of gasoline have been recovered to date. The Unified Command has refined the estimated volume of gasoline discharged in the incident to approximately 21,168 gallons, based on recent hydraulic modeling.

Sunday, Jan. 7, 2024 -- 4:45 p.m.

Crews will reopen SR 534 to two-way traffic by 6:00 am, Monday, January 8. For the safety of work crews, please use caution while driving through the response area

Temporary closures may occur as flaggers help facilitate truck movement in and out of the response area. 

Response crews are using a shuttle service to and from the work zone to reduce congestion on SR 534. 

Conway Hill Road has returned to one-way westerly traffic.  

Friday, Jan. 5, 2024 -- 1:30 p.m.

One lane of SR 534 remains closed at the spill site. Unified Command is evaluating strategies to reduce traffic congestion near the site.

The Unified Command is working on plans to remove remaining contaminated soil and potentially sediment along the east bank of Bulson Creek (Hill Ditch). Containment boom and skimming operations continue to recover any gasoline entering the ditch.

Water samples taken shortly after the spill from Bulson Creek (Hill Ditch), close to the spill site, temporarily showed elevated levels of gasoline-related contaminants. Continued sampling at these locations has shown no levels that present a concern to human health and safety.

Ongoing sampling activities within the area have included the collection of over 260 surface water and sediment samples in nearby waterways including Bulson Creek (Hill Ditch), Skagit River, and Skagit Bay. Sampling downstream of the spill site continues and no exceedances of health-based screening values for either surface water or sediment have been reported at any location since December 22, 2023. These values are protective of both human health and the environment.

Over 5,000 real-time readings and 102 analytical air samples have been collected in the community, all of which continue to indicate no public health risk from gasoline fumes.

Two additional deceased birds have been recovered and have been sent for testing. The condition of the birds suggests the spill was not likely the cause of death.

Fencing and pitfall traps were installed to keep amphibians out of impacted areas. Traps are designed to allow water to drain and will be checked at least twice daily by wildlife personnel.

Friday, Dec. 29, 2023 -- 6:30 p.m.

Crews have removed 289 trees in the area bordering the west edge of the farm field and east shoreline of Hill Ditch. Removal of the trees is required for removal of underlying contaminated soil. 

Approximately 8,324 gallons of gasoline have been recovered to date. Approximately 25,326 gallons were discharged in the incident.

One lane of SR 534 remains open as cleanup work proceeds. Traffic flaggers are assisting motorists through the area.

Residents who live along Hill Ditch may continue to see sheen as pockets of gasoline that were trapped by vegetation and other debris on the water and along the shoreline are released by wind, rain, and the natural rise and fall of stream levels.

Tuesday, Dec. 26, 2023 -- 5:45 p.m.

On Wednesday, Dec. 27, crews will begin removing trees in the area bordering the west edge of the farm field and east shoreline of Hill Ditch. This work is expected to take about four days. Removal of the trees is required for removal of underlying contaminated soil.

Aerial view of response site.

Red shading indicates tree removal area.

Friday, Dec. 22, 2023 -- 5 p.m.

Today, responders continued the initial excavation of impacted soils near the source of the gasoline release. As of 5 p.m. on December 21, 437 cubic yards of soil has been loaded onto trucks for treatment and disposal at a hazardous waste facility in Arlington, Oregon. 

Drone footage of the excavation is available for Dec. 21 and Dec. 22, as well as photos of today's work

Eight landowner wells along Hill Ditch have been tested for gasoline-related contaminants. The results have shown no levels above US EPA safe drinking water standards. There is no indication that any run-off from the spill reached these wells. 

Surface water testing at 16 sites is on-going. To date, almost 100 individual surface water samples have been collected and we have results from 51. To date, results show that the highest concentrations of gasoline-related contaminants are at the sites closest to the spill and taper off dramatically south of State Highway 534. 

There continues to be no evidence of gasoline-related contaminants that would be harmful to human or aquatic health in the Skagit River or Skagit Bay.  
 
Operations at the site will continue through the holiday weekend.

Tuesday, Dec. 19, 2023 -- 7:00 p.m.

Approximately 7,388 gallons of gasoline have been recovered to date. This number will be updated when the oily/water mixture being collected has sufficient time to settle and be measured. Approximately 25,000 gallons were released in the incident.

Responders have removed approximately 275 cubic yards of impacted soils near the source of the gasoline release. The soils were loaded onto trucks and will be transported to a hazardous waste facility in Arlington, Oregon, for treatment and disposal.

Olympic Pipeline spill in Conway WA _ Overhead view of the site

Olympic Pipeline spill near Conway WA _ Dec. 19, 2023. Topsoil excavation

Olympic Pipeline spill in Conway WA_ Hill Ditch

 

Monday, Dec. 18, 2023 -- 6:00 p.m.

Teams have evaluated 4.4 miles of shoreline for potential spill impacts, and trace impacts from the spill have been found on 1/3 of a mile of shoreline.

Approximately 2,300 feet of boom are currently deployed in the response.

Approximately 7,000 gallons of gasoline have been recovered to date. This number will be updated when the oily/water mixture being collected has sufficient time to settle and be measured. Approximately 25,000 gallons were released in the incident.

Members of the public who come upon injured or deceased wildlife are asked not to touch or relocate affected wildlife and to call 1-800-22BIRDS.

Saturday, Dec. 16, 2023 -- 6:00 p.m.

Teams have evaluated 3.9 miles of shoreline for potential spill impacts, and trace impacts from the spill have been found on 699 feet of shoreline. 

Area residents who live along Hill Ditch may continue to see sheen as pockets of gasoline that were trapped by vegetation and other debris on the water and along the shoreline are released by wind, rain, and the natural rise and fall of stream levels. Teams are locating and removing these pockets of gasoline.

Friday, Dec. 15, 2023 -- 6:00 p.m.

Unified Command released a statement regarding recreational and tribal Dungeness crab fisheries. There are no known impacts to these fisheries from the Olympic Pipeline spill in Conway. Unified command is conducting water sampling in the Skagit River and Skagit Bay, and will collect samples of Dungeness crab. When results of this sampling are available, it will be shared with tribes, public health agencies, and Washington Department of Fish and Wildlife. Any impacts to recreational, tribal, or commercial fisheries will be included in Unified Command updates.

Teams have evaluated 3.7 miles of shoreline for potential spill impacts, and trace impacts from the spill have been found on 436 feet of shoreline.

Approximately 2,300 feet of boom are currently deployed in the response. 

Thursday, Dec. 14, 2023 -- 9:30 p.m.

The pipeline was shut down and the leak was stopped on Sunday, Dec. 10. Efforts to clean up spilled gasoline are continuing. Approximately 6,993 gallons of gasoline have been recovered to date. Approximately 25,326 gallons were released in the incident.

Members of the public who come upon injured or deceased wildlife are asked not to touch or relocate affected wildlife and to call 1-800-22BIRDS. Teams have recovered one American beaver, one pine siskin bird, one mallard duck, and one American widgeon duck deceased because of the spill.

Teams have evaluated 5,280 meters (3.5 miles) of shoreline for potential spill impacts and have found 30 meters (98 feet) impacted by the spill.

After regulatory approval, the pipeline system was restarted on Dec. 13. 

A claims center has been established by the Olympic Pipeline. Please call 1-866-616-1558 to report any personal or property damages resulting from the spill.

Wednesday, Dec. 13, 2023 -- 7:30 p.m.

Approximately 271 gallons of gasoline were recovered today, bringing the total recovered to date to approximately 6,993 gallons. 

A claims center has been established by the Olympic Pipeline. Please call 1-866-616-1558 to report any personal or property damages resulting from the spill.

Members of the public are asked not to touch or relocate affected wildlife and to call the wildlife hotline (1-800-22BIRDS). To date, teams have recovered one American beaver, one pine siskin bird, and one mallard duck deceased as a result of the spill. 

Tuesday, Dec. 12, 2023 -- 7:00 p.m.

The unified command has adjusted the amount of gasoline spilled to approximately 25,326 gallons. Of that, 5,292 gallons of gasoline remained in the vault and the remainder was released into the environment. Approximately 6,722 gallons have been recovered to date.

Regrettably, wildlife response teams have recovered one deceased beaver, which was determined to have died as a result of the spill. Members of the public are asked not to touch or relocate affected wildlife and to call the wildlife hotline (1-800-22BIRDS). 

SR 534 remains open to one-way traffic as cleanup work proceeds. The unified command appreciates the community’s patience and understanding during these traffic disruptions.

Air monitoring conducted by the Department of Ecology and by BP at EPA’s and Ecology’s direction continues to indicate no public health risk from gasoline fumes. 

Monday, Dec. 11, 2023 -- 5:00 p.m.

Unified Command has determined that the leak was caused by the failure of 3/8” tubing inside a concrete vault that connected one of the pipelines to a pressure sensor. The current estimate is that approximately 25,000 gallons of gasoline was released into the environment, with 5,000 additional gallons captured by the vault.

Approximately 1600 feet of absorbent and containment boom has been placed at various locations in Hill Ditch and Bulson Creek as far as 2.25 miles downstream of the release site. No gasoline or sheen has been seen on the Skagit River. Air quality monitoring continues to indicate that there is no public health risk from gasoline fumes.

SR 534 will be opened to one-lane traffic at approximately 6 a.m. on Tuesday, Dec. 12.

Monday, Dec. 11, 2023 -- 1:00 p.m.

The unified command has placed approximately 1,600 feet of absorbent and containment boom in nearby Hill Ditch and Bulson Creek. There are no signs that gasoline has reached the Skagit River.
Hill Ditch and Bulson Creek both support salmon and many species of waterfowl and other wildlife. Thus far, there are no confirmed injuries or deaths of fish or wildlife in the spill area.

Air monitoring conducted by the Department of Ecology and by BP at EPA’s and Ecology’s direction continues to indicate no public health risk from gasoline fumes. 

Sunday, Dec. 10, 2023 -- 1:00 p.m.

Ecology is responding to a gasoline release from the Olympic Pipeline near Mt. Vernon. A Unified Command has formed consisting of Ecology, the U.S. Environmental Protection Agency, the Swinomish Indian Tribal Community, the Lummi Nation, Skagit Dept. of Emergency Management, and BP. 

A large concrete vault associated with the pipeline has overfilled, causing gasoline to flow overland and into a nearby irrigation canal named Hill Ditch, which discharges into Bulson Creek. Spill response contractors are on scene, and have boomed Hill Ditch and are recovering gasoline. Additional oil containment boom has been placed at locations downstream.

Highway 534 has been closed from the I-5 off-ramp to Bulson Road, a distance of approximately 1 mile. Air monitoring has been performed at nearby homes and gasoline vapor concentrations do not require evacuations.
 
The volume of gasoline released is unknown and the cause of the leak is under investigation.

News releases

Media contact

Scarlet Tang, Ecology, scarlet.tang@ecy.wa.gov, 206-920-2600

Franji Mayes, Ecology, franji.mayes@ecy.wa.gov, 360-529-7063

Jennifer Rogers, Skagit County, jrogers@co.skagit.wa.us, 360-630-6604

Pamela Brady, BP, pamela.brady@bp.com, 360-920-1171

Bill Dunbar, Environmental Protection Agency, dunbar.bill@epa.gov, 206-245-7452