1215 North 45th St., Seattle, WA 98103

SITE STATUS - DECEMBER 2020

The Department of Ecology (Ecology) has negotiated a legal agreement called an Agreed Order (AO) with Chevron Environmental Management Company (CEMC) and Stone Way Apartments LLC (Stone Way) for the Chevron 209335 cleanup site (Site). The AO names CEMC and Stone Way as Potentially Liable Persons (PLPs) and requires them to investigate the site and develop cleanup alternatives, in a document called a Remedial Investigation /Feasibility Study (RI/FS) Report, and to develop a plan based on that report, called a draft Cleanup Action Plan (dCAP). 

Ecology is hosting a public comment period for the following documents from December 7, 2020-January 20, 2021. We invite you to review and comment on them using the links below, and get more information by attending one of our online public meetings (see links to Public Meeting below to register).

• Agreed Order – requires the PLPs to investigate environmental conditions, complete a RI/FS Report that presents the results of the investigation and an evaluation of the cleanup alternatives. The dCAP describes how the selected cleanup alternative will be performed.  

• Public Participation Plan – describes how Ecology will inform the community about Site activities and opportunities to be involved in the cleanup process.

Site Location Diagram

SITE BACKGROUND

The Site is located at 1215 N. 45th Street, Seattle, WA 98103 (Property). The Property is currently owned and operated by Stone Way as a mixed-use affordable housing building.
A service station operated at the Property from at least 1935. Standard Oil Company (Standard) (a predecessor of Chevron U.S.A. Inc.) purchased the Property in 1954 and operated a gasoline service station at the Property until the removal of the service station building and service garage in 1969. Standard sold the Property in 1978 to the Seattle Housing Authority (SHA). The SHA then sold the Property to Housing Resources Group (HRG) in 2005, which immediately transferred ownership of the Property to Stone Way. The Property has since been developed into a four-story, mixed-use retail/residential building with an underground parking garage.

Previous Cleanup Work

2005: The Property was excavated, and impacted soil was removed to a depth of 13 to 18 feet below the original grade. In addition, a total of 20 large-diameter bucket auger borings were drilled to approximately 42 feet below the original ground surface to remove deep 
petroleum-hydrocarbon impacted soil. Approximately 2,490 tons of soil were removed and backfilled with clean soil or control-density fill (CDF). Five underground storage tanks were removed from the Property as well. The underground parking garage is next to North 45th Street, Stone Way North and a utility corridor that prevented further excavation. Additional groundwater monitoring wells were installed in 2005.

2005 – 2018: Groundwater samples were collected semi-annually through 2018. Additionally, light non-aqueous phase liquids (LNAPL, or petroleum products that float on top of groundwater) were removed from one monitoring well (bi-weekly to daily) from February 2006 to August 2006. A surfactant injection for enhanced LNAPL recovery occurred in 2013. 

2018 – Today: LNAPL continued to be observed at the Site through 2018 in one groundwater monitoring well. The remaining petroleum contamination does not likely pose a health risk to the businesses or residents of the building due to the presence of a below ground parking garage, garage ventilation system and a protective vapor barrier beneath the building. A Vapor Intrusion Assessment (VIA, or study of the air in the garage) will be conducted during the remedial investigation to confirm this understanding.

Chemicals of Concern

Chemicals remaining in soil and groundwater include:

• Petroleum products (Gasoline, Diesel, Oil-range Total Petroleum Hydrocarbons) 
• Benzene, Toluene, Ethyl-Benzene, and Xylene (BTEX)

ECOLOGY'S CLEANUP PROCESS

The Model Toxics Control Act (MTCA) is Washington’s environmental cleanup law.  It provides requirements for contaminated site cleanup and sets standards that protect human health and the environment.  Ecology enacts the MTCA and oversees cleanups. 
The MTCA site cleanup process is completed in steps over a variable timeline (see graphic below). 

RELATED INFORMATION

• Washington State Department of Ecology website   
• Washington State Department of Ecology Cleanup Sites website  

ADDITIONAL RESOURCES

• Acronyms used by the Toxics Cleanup Program
• Cleanup Process: Major Steps & Definitions
• Data Submittal Requirements for All Cleanup Sites
• Toxics Cleanup publications