Proposed Petition for Removal from the Hazardous Sites List
Public Comment Period: November 16, 2023 – December 17, 2023
15410 Main Street, Duvall, WA 98019
FS ID# 48143795
CS ID# 9397
The Washington State Pollution Liability Insurance Agency (PLIA) invites the public to comment on the cleanup at Town Center Mini Mart Texaco (Site). This notice is a proposal to remove this Site from the Department of Ecology’s Hazardous Sites List.
The Town Center Mini-Mart Property Site is currently occupied by a service station and convenience store which were constructed in 1987. In 2009, two 10,000-gallon gasoline underground storage tanks (USTs) and one 12,000-gallon gasoline UST and associated piping were decommissioned and removed from the Site. At that time, 1,200 tons of petroleum-contaminated soil (PCS) were also removed from the Site. PCS remained in place at some sidewall and bottom locations upon completion of the excavation.
In 2019, an additional excavation removed 550 tons of additional PCS from the Site. Additionally, approximately 1,040 pounds of powdered Regenesis ORC Advanced amendment was placed within the excavation at the water table to enhance residual petroleum biodegradation in soil and groundwater. An impervious paved surface has since been installed at the Site over the remaining PCS exceeding state cleanup requirements.
PLIA performed regulatory oversight of the Site under the agency’s Technical Assistance Program (TAP). Based on the Site review, soil sampling, and vapor and groundwater monitoring results, PLIA has determined that the Site meets the substantive requirements of the state clean up regulations regulations, Chapter 173-340 WAC Model Toxics Control Act, and no longer poses a threat to human health or the environment. The inaccessible residual contamination left in place will be managed through institutional controls under an environmental covenant filed with King County.