It will take years to mitigate the petroleum contamination that has spread from a former Texaco gas station site to neighboring southwest properties in Lower Queen Anne, the extent of which is still being assessed.

Vibrant Cities was aware of the contamination on the Manhattan Express Deli site before purchasing the property on the southwest corner of West Roy Street and Queen Anne Avenue North in 2017.

Vibrant Cities was cleared by the West Design Review Board to seek permits for its 93-unit Roystone Apartments project at 631 Queen Anne Ave. N. back in February, and had informed the Washington Department of Ecology about its plans in 2018. The developer’s interim cleanup proposal was deemed a cost-effective approach to addressing contamination on the property, said Ecology site manager Jill Song during a June 27 public meeting about the Texaco 211577 Monterey Cleanup Site.

Vibrant Cities cofounder and principal Pui Leung said Ecology has been great to work with in remediating the site. The hope is to have the property cleaned up and cleared for redevelopment by Q4 2019.

“A lot depends on the city process and also Ecology’s timeline,” he said.

Texaco owned the property at 631 Queen Anne Ave. N. from 1927 to 1977, at which point William and Erma Arnold purchased the site and operated its own service station there. They attempted to sell the property in 1989, according to Ecology, but the sale was rescinded in 1993 due to petroleum hydrocarbon contamination, and the Arnolds were ordered to stop selling gasoline. Seven underground storage tanks were removed from the property, and one was abandoned in place, filled with concrete.

Manhattan Express Deli began operating on the site in 1993. Vibrant Cities purchased the property in October 2017, and the deli closed in 2018; the building served as a pop-up produce market through the holidays last year.

Prior to addressing the contaminants found around the former gas station, Ecology worked with the Arnolds and Texaco to clean up the old Monterey Apartments to the southwest of the Roystone project site.

“A good portion of this area is contaminated with petroleum contamination that is coming from this Texaco facility,” Song said.

The Seattle Fire Department received multiple complaints about a gas odor coming from the Monterey’s basement between 1978 and 1985, when petroleum was found on top of a basement sump, Song said.

Ecology installed a vapor alarm in the basement and two recovery wells on the Monterey site between 1986-87, extracting 150 gallons of petroleum-based contaminants.

After Ecology shut down the gas station at 631 Queen Anne Ave. N., the agency installed a soil vapor extraction (SVE) and groundwater recovery system with a spray aeration vacuum extraction treatment system (SAVE). The SAVE system was replaced with a catalytic oxidizer in 1996, and Chevron Environmental Management Company (CEMC) replaced the SVE system with a dual phase extraction system in 2006, which it operated until April 2008, according to Ecology.

Texaco is a subsidiary of Chevron, which is identified as a potentially liable persons (PLP) in the Agreed Order that legally commits the company and Vibrant Cities to completing their respective remediation work.

The remediation system CEMC installed was shut down in 2008, when contaminant concentrations were too low for it to continue being effective, Song said, and vapor samples collected at Monterey and the Del Roy apartments, immediately west of the Texaco site, met state cleanup standards.

Vibrant Cities is responsible for its property, including sidewalk at West Roy Street and Queen Anne Avenue North that had once been part of the Texaco site.

That will include removing and disposing of contaminated soil at a permitted facility, and pumping and treating groundwater, which can then be discharged into the city’s sewer system, Song said. Once Roystone is built, new monitoring wells and a vapor mitigation system will be installed. Barriers will be installed at the basement level and along the property boundaries.

The agreed order, interim action work plan, SEPA checklist and determination of non-significance, and a public participation plan are available here for public review and comment through July 23.

CEMC is early in the process of assessing the extent of remediation work needed to address remaining soil and groundwater contamination at Monterey and Del Roy, as well as at Queen Anne Arms, Bank of America and a U-Park lot on the west side of First Avenue North. The groundwater contamination area is greater, Song said, due to its continuous flow southwest of the Texaco site, and a revised site boundary will be included in an environmental investigation mandated under the agreed order.

CEMC is expected to complete its remedial investigation by the end of 2020, making a report available for public review by mid-2021, Song said, and then a feasibility study will be conducted to determine how to proceed with cleanup; that report is expected to be available for review by early 2022, followed by a draft cleanup action report in 2023.