Dunsmuir Historical Oil – Update #11

June 14, 2024

Operations to complete wet excavation (below the water table) for the southern half of the railroad site will resume in the coming weeks. Installation of an in-river isolation barrier (IRIB), consisting of large canvas sacks filled with sand and rocks, is underway and will be completed prior to the start of excavation activities. River flows are subsiding but remain swift.

River Safety Message signage has been posted in various public locations upstream of the railroad yard from the Sacramento Avenue overcrossing to Hedge Creek Falls.

Excavation depths vary throughout the site but will be taken down to bedrock in most areas. The areas are being backfilled with clean imported material, compacted, and graded to final shoreline configuration.

Excavated material will be loaded onto trucks or railcars and properly disposed of off-site.

The containment boom in the river along the retaining wall was removed during high winter and spring flows as it may have dislodged and become hazardous. Boom will be reinstalled on the outside of the IRIB and prior to initiating 2024 excavation activities. River monitoring will continue, and cleanup equipment is staged onsite if needed. Containment strategies have

been effective in confining an oil seep observed last year and no visible sheen or product has been observed outside of the containment boom since.

Dust control measures taken at the site on roads and soil stockpiles include application of water using a water truck. As needed, a soil stabilizer and dust control agent, Gorilla-Snot, is being applied utilizing a water truck. Gorilla-Snot is non-toxic when dry, and commonly used for dust and soil control.

Truck traffic through the City of Dunsmuir will increase with the onset of excavation activities.

Dunsmuir Historical Oil Update #10

January 5, 2024

Excavation operations have been completed for the 2023 work season and the site is being winterized in preparation for inclement weather. Operations to complete wet excavation for the southern half of the railyard site will resume after the 2024 winter weather season.

Dry excavation for the entire railyard site has been completed. The retaining wall along the river was not removed in 2023 and will remain in place over the winter. Removal of the wall will occur during 2024 operations. The in-river isolation barrier has been removed while construction activities cease for the winter and will be reinstalled this year.

Excavation depths vary throughout the site but will be taken down to bedrock in most areas. Excavated areas are being backfilled with clean imported material, compacted, and graded to final shoreline configuration.

Containment boom currently remains in the river along the retaining wall and weekly river monitoring is ongoing. In anticipation of wet weather and river level rise, the boom will likely be removed as it may become hazardous with high flows. Additional response equipment is staged onsite if needed.

Increased truck traffic through the City of Dunsmuir will continue while backfill material is being delivered to the site and excavated material is being off hauled from the stockpile pads. Truck traffic will slow down once the site is winterized and hauling of material to or from the site is complete for the work season.

Dunsmuir Historical Oil – Update #9

October 23, 2023

Excavation work continues along the Upper Sacramento River at the Dunsmuir Railyard, where cleanup and restoration is ongoing to address historic petroleum seepage.

Planned excavation will continue through December before winterizing the site in preparation for inclement weather. The overall project schedule was updated during the summer and proposes to carry out operations through the end of 2024.  

Dry excavation for the entire north railyard site has been largely completed. Wet excavation (below the water table) began in mid-September 2023 for the northern half of the work site, and is expected to be completed in November 2023.

Operations continue to remove the retaining wall along the river. The wall will be removed prior to initiating shoreline restoration activities. An in-river isolation barrier was installed prior to initiating wet excavation activities to keep product contained within the immediate project area. The barrier consists of sand and rock filled supersacks, as well as sorbent boom and a silt curtain.

During excavation operations on October 18, a turbidity plume (a plume of sediment temporarily suspended in the water column) was released outside of the in-river isolation barrier into the Sacramento River. Whereas turbidity is expected with the excavation work, there was an unknown breach causing the plume to be released. Excavation operations ceased, and crews were on-scene repairing the breach. 

With the installation of the in-river isolation barrier, River Safety Message signage was posted in September at various locations upstream of the barrier. 

Excavation depths vary throughout the site but will be taken down to bedrock in most areas. Excavated areas will be backfilled with clean imported material, compacted, and graded to final shoreline configuration. Excavated material is being loaded onto trucks or railcars and properly disposed of off-site.

Containment boom remains in the river along with the in-river isolation barrier and weekly river monitoring is ongoing. Additional response equipment is staged onsite if needed. Containment strategies have been effective in confining an oil seep and no visible sheen or product has been observed outside of the containment boom.

Shoreline restoration is planned to be completed in early 2024, which will expand riparian habitat.

Increased truck traffic through the City of Dunsmuir will continue as excavation work and transfer of material to the south stockpile area continues. Signs along the trucking routes are placed along the streets notifying times and dates of increased truck traffic and any no parking zones as needed.

Dunsmuir Historical Oil – Update #8

October 18, 2023

At approximately 12:00 pm today (October 18, 2023) a turbidity plume (a plume containing sediment temporarily suspended in the water column) was released outside of the in-river isolation barrier (IRIB) along the Dunsmuir Railyard into the Sacramento River due to ongoing operations to remove contaminated soil. Excavation operations were occurring along the shoreline which created turbidity in the water.  Whereas turbidity is expected with the excavation work, there was an unknown breach in the IRIB causing the plume to be released. Excavation work has ceased, and crews are currently on-scene repairing the breach.

Safety information on the Dunsmuir Historical Oil response

Active restoration and cleanup is occurring at the Dunsmuir Railyard located along the Sacramento River. Please read the flyer on important safety information for the public planning to engage in recreational activities in the area.

For more information on the Dunsmuir Historical response, go to https://calspillwatch.wordpress.com/tag/dunsmuir-historical-oil/

Media contact: Mary Fricke, Public Information Officer, Mary.fricke@wildlife.ca.gov or 916-417-0210

Dunsmuir Historical Oil – Update #6

May 30, 2023

After pausing excavation activities over the winter months due to inclement weather,
cleanup and restoration efforts are set to resume this month at the Dunsmuir Railyard,
where historic petroleum seepage has impacted soil and the adjacent Upper
Sacramento River.

Two buildings will be demolished this month so that excavation can resume in June. Excavated material will be loaded onto railcars and trucks for proper disposal, and
once the project is complete, the shoreline will be expanded and restored with native
plants, generating additional riparian habitat.

Increased truck traffic through the City of Dunsmuir will continue as excavation work and
transfer of material to the south stockpile area continues. Signs along the trucking
routes are placed along the streets notifying times and dates of increased truck traffic
and any no parking zones as needed.

OSPR scientists continue to monitor the river and there have been no observed impacts
to wildlife.

Dunsmuir Historical Oil – Update #5

Dec. 8, 2022

Excavation work continues along the Upper Sacramento River at the Dunsmuir Railyard, where a Unified Command of state and federal agencies (including OSPR and Union Pacific Railroad), is overseeing cleanup and restoration efforts that stem from historic petroleum seepage. 

Crews have continued excavation directly behind a retaining wall along the river, removing soil to a depth of 10 feet. Officials are mitigating potential runoff from incoming storms by covering the soil and taking other precautions.

Excavated material is being loaded onto trucks that transport the material offsite to an appropriate waste disposal site. Construction of a stockpile area in the south railyard has been completed and trucking of excavated material to the stockpile area will begin this month. A de-watering system has been constructed in the north railyard in preparation of shoreline excavation planned for next year.

Truck traffic through the City of Dunsmuir increased with the onset of excavation work to remove contaminated soil and to deliver clean fill. Signs are posted along the trucking routes and placed along the streets notifying times and dates of increased truck traffic and no parking zones as needed.

Dunsmuir Historical Oil – Update #4

UPDATE on the Dunsmuir Historical Oil response: Excavation work started along the Upper Sacramento River at the Dunsmuir Railyard, where a Unified Command of state and federal agencies (including OSPR and Union Pacific Railroad), is overseeing cleanup and restoration efforts that stem from historic petroleum seepage. 

Crews began excavating activities last week, removing soil to a depth of 10 ft. directly behind the retaining wall along the Sacramento River. Officials are mitigating potential runoff from incoming storms by covering the soil and taking other precautions.

Excavated material is being loaded onto trucks that transport the material offsite to an appropriate waste disposal site. Construction of a stockpile area in the south railyard is nearing completion and trucking of excavated material to the stockpile area will begin as needed.

Truck traffic through the City of Dunsmuir increased with the onset of excavation work to remove contaminated soil and to deliver clean fill. Signs are posted along the trucking routes and placed along the streets notifying times and dates of increased truck traffic and no parking zones as needed.

Dunsmuir Historical Oil – Update #3

Oct. 14, 2022

UPDATE on the Dunsmuir Historical Oil response: Excavation work is set to begin next week along the Upper Sacramento River at the Dunsmuir Railyard, where a Unified Command of state and federal agencies (including OSPR), is overseeing cleanup and restoration efforts that stem from historic petroleum seepage. 

Contractors will load excavated material onto trucks and will transport the material offsite to an appropriate waste disposal site. Construction of a stockpile area in the south railyard will be completed, and trucking of excavated material will begin as needed.

Truck traffic through the City of Dunsmuir will increase with the onset of excavation work to remove contaminated soil and to deliver clean fill. Signage along the trucking routes will be placed along the streets notifying times and dates of increased truck traffic and any no parking zones as needed.

Dunsmuir Historical Oil – Update #2

June 29, 2022

A Unified Command of federal and state agencies, and Union Pacific Railroad (UPRR) continues to oversee cleanup and restoration at the Dunsmuir railyard, where historic petroleum seepage has impacted soil, groundwater, and the Upper Sacramento River.

Construction operations recently resumed following a winter hiatus and are expected to continue during the warmer months through 2023. So far this year, in addition to routine in-river boom maintenance and inspections, contractors have begun drilling and collecting soil samples as well as abandoning wells that lie within the footprint of planned excavations.

Planned work for the remainder of the project includes:

-Removal of riverfront retaining walls and the adjacent walkway -Excavation of oil-impacted soil along 1,000 feet of shoreline -Riverbank restoration along the shoreline to increase river capacity and create additional habitat for birds and fish.

CDFW-OSPR has monitored the waterway since 2018 and has not observed any impacts to wildlife. Additionally, the state Office of Environmental Health Hazard Assessment (OEHHA) assessed the river (as recently as May 2022), and recommended the fishery remain open after concluding the situation did not reach the threshold of being a threat to public health.

(Scroll down for prior updates and background information on the response)