The site housed an above-ground black tank that stored petroleum products, primarily the thick, heavy oil known as bunker C for fueling trains. The site also had an above-ground red tank that was used to store and transfer diesel. Areas of soil are contaminated, and a 7-acre plume of petroleum rests on groundwater 170 feet underground.
|Cross-section showing petroleum contamination in soil and groundwater|
(Courtesy of ERM)
Excavation with offsite disposal or capping are proposed for contaminated shallow soil. Five groundwater cleanup options are under consideration: biodegradation, bioventing/biosparging, bioventing/biosparging and manual petroleum removal, bioventing/biosparging and steam-enhanced extraction, and smoldering combustion. Bioventing/biosparging is BNSF and Marathon's preferred cleanup option.
These cleanup methods are summarized in the fact sheet and fully described in the remedial investigation and feasibility study report.
When contamination intersects with a freewayThe Washington State Department of Transportation (WSDOT) is building the North Spokane Corridor (NSC) to connect US Highway 395 with Interstate 90 in Spokane. The Hillyard portion of the NSC is within the Black Tank cleanup site. Ecology, BNSF, Marathon, and WSDOT are working together to keep both projects running smoothly.
BNSF and Marathon have committed to a cleanup timeframe of less than 20 years, and WSDOT is planning freeway construction work to accommodate multi-purpose cleanup infrastructure so cleanup options will not be limited by the presence of the NSC.
Educating the public about the Black Tank site and soliciting your input are important steps in the cleanup process. We have been impressed by the outpouring of public interest, which gave us the opportunity to meet with the community about this cleanup site 17 times since late 2015! The cleanup and the freeway design have and will continue to benefit from meaningful public engagement.
It’s all about the life-giving aquiferOur business is protecting people and the environment. The Spokane-Valley Rathdrum-Prairie Aquifer provides drinking water to nearly 500,000 residents in the Spokane area. Protecting this vital, sole source of drinking water is our top priority for this site. Not only do we care about your health and the environment, but we drink that water, too!
Because the contamination is a heavy oil, it is staying on top of groundwater with very little mixing occurring (imagine oil and vinegar dressing that isn’t shaken up). Because water wells are not located close to the site, drinking water is not affected by the contamination at this time, and we monitor it regularly.
Next stepsPlease submit comments to Jeremy Schmidt online, by email, or mail (4601 N. Monroe, Spokane, 99205) by June 22. We will respond to the comments we receive.
Then we’ll use the data gathered thus far and your feedback to draft a cleanup plan. We will hold a public meeting during the comment period for that cleanup plan.
There is no easy answer, but working together, understanding one another’s values and constraints with a willingness to compromise, we will protect people and the environment, preserve our precious drinking water, and successfully build a freeway.