Stillwater Holdings Chevron

After being identified as the source of the spill in September 2023, Stillwater Holdings hired an environmental consultant and contractor to investigate and help create a cleanup plan. Last November, the owner informed Ecology and local officials that they were working with their insurance company to fund and remove the leaking tank, and then clean up the contaminated soil. Stillwater Holdings’ insurance policy includes up to $1 million to cover potential spills and leaks. 

Ecology held a public comment period for the draft State Environmental Policy Act documents for the underground storage tank system replacement April 1–15, 2024. We responded to comments from four people, and we thank them for their input.  

In May, Stillwater Holdings told Ecology that they could pay for little or no more work, and that Ecology would need to take over. By law, Stillwater Holdings is responsible for the pollution, responding to the emergency, and cleaning up the contamination. 

Generally, Ecology does not use taxpayer funds to pay cleanup costs when the company has money available. Ecology is prepared to take over and fund the Walla Walla cleanup if needed because the spill poses significant risks to the community.

Local, state, and federal agencies, along with third-party contractors, have deemed the area safe for residents and visitors with protection measures and air quality monitoring in place. Testing of Walla Walla's municipal water and wastewater systems and nearby Mill Creek has shown no evidence of contamination.

On September 14, 2023, the Marcus Whitman Hotel was evacuated due to volatile organic vapors entering the building, also known as vapor intrusion. The Walla Walla Fire Department called in Ecology’s Spill Response Team to help assess the situation and identify the source. 

Testing identified potentially harmful vapors and gasoline in the basement, and in two nearby buildings. The buildings were ventilated to eliminate the risk of an explosion, and the buildings’ drainage systems, also known as sumps, were pumped to reduce vapor concentrations. 

An investigation found that gasoline from a Stillwater Holdings’ underground tank had leaked and was pooling in adjacent buildings’ sumps. The leaking tank was taken out of service and has been emptied.