King County Metro Transit S Annex

11911 E Marginal Way S Tukwila, King County
Facility Site ID: 8422289 Cleanup Site ID: 7790

  • Site Status

  • No Further Action

More about cleanup

Status

Ecology issued a Site No Further Action opinion letter for this site (Voluntary Cleanup Program project NW3301) on February 13, 2024.

Site Background

The property is located in an industrial-zoned area in the City of Tukwila and was farmland prior to initiation of development by Metro Transit in 1985.  The South Facilities area of the property on the west includes the operations building and the Annex area of the property on the east consists of bus parking lots, open storage, and a training yard.  During removal of three underground storage tanks (USTs) from the property in 1997, petroleum-contaminated soil and groundwater was encountered.

Site Cleanup In Process

Soil and groundwater samples collected from September 2019 through November 2022 confirmed compliance with Model Toxics Control Act cleanup levels, the absence of soil-vapor and surface-water contaminant exposure pathways, and successful completion of the Site cleanup.

Contaminants Of Concern

Gasoline-, diesel-, and oil-range petroleum hydrocarbons (TPH-G, TPH-D, and TPH-O), and benzene, toluene, ethylbenzene, and xylenes (BTEX) into the Soil and Groundwater.

Voluntary Cleanup Program

This site was cleaned up under our Voluntary Cleanup Program, which provides technical help to owners of contaminated sites.

Voluntary Cleanup Program customers pay fees to cover our costs for technical help and reviewing cleanup reports. Sites in this program must meet the same cleanup standards as the sites Ecology manages under legal orders.

Places to see print documents
Legal 1
Document Title Document Date Document Type
King County Metro Transit S Annex - RCU Status Update 3/4/2013 Early Notice Letter
Technical Reports 12
Document Title Document Date Document Type
Remedial Investigation Addendum, King County Metro South Facilities 2/28/2023 Remedial Investigation Report
King County Metro Transit S Annex—NW3301 RI/FS Summary Report 11/13/2020 Site Specific Technical Document - other
King County Metro Transit S Annex—Phase II ESA Report 5/21/2020 Site Specific Technical Document - other
King County Metro Transit S Annex—Push Probe Investigation Results 4/21/2020 Site Specific Technical Document - other
King County Metro Transit S Annex—Status Update 10/22/2019 Site Specific Technical Document - other
King County Metro Transit S Annex—Groundwater Sampling Report 1/10/2019 Site Specific Technical Document - other
King County Metro Transit S Annex - SHA Rank Letter 8/19/2015 Site Specific Administrative Document - other (Administrative correspondence)
King County Metro Transit S Annex - Site Hazard Assessment 8/19/2015 Site Hazard Assessment Report
King County Metro Transit S Annex - SHA Notification Letter 4/7/2015 Site Specific Administrative Document - other (Administrative correspondence)
King County Metro Transit S Annex - UST Closure Assessment Report 1/18/1997 Site Specific Technical Document - other
King County Metro Transit S Annex - Pre-Construction Assessment Report 1/30/1995 Site Specific Technical Document - other
King County Metro Transit S Annex - Report on Geotechnical Investigtion 4/27/1984 Site Specific Technical Document - other
Voluntary Cleanup Program 3
Document Title Document Date Document Type
Site No Further Action Opinion Letter NW3301 2/13/2024 VCP Opinion on Site Cleanup – NFA
Technical Assistance Regarding Silica Gel and Groundwater Samples 12/1/2023 VCP Technical Assistance
King County Metro Transit S Annex - NW3301 Opinion on Remedial Action 5/7/2021 VCP Opinion on Remedial Investigation
There may be more documents related to this site. To obtain documents not available electronically, you will need to make a public records request.

Places to see print documents

  • Northwest Regional Office
    15700 Dayton Ave N
    Shoreline, 98133
    Please schedule an appointment to view print documents at this location.

Contaminants 5

Contaminant Type
Soil
Groundwater
Surface Water
Air
Sediment
Bedrock
Non-Halogenated Organics - Benzene RB RB
Non-Halogenated Organics - Other Non-Halogenated Organics RB RB
Non-Halogenated Organics - Petroleum-Diesel RB RB
Non-Halogenated Organics - Petroleum-Gasoline RB RB
Non-Halogenated Organics - Petroleum-Other RB RB
S
Suspected
C
Confirmed Above Cleanup Levels
B
Below Cleanup Levels
RA
Remediated-Above
RB
Remediated-Below
R
Remediated
This contaminant list was based on our best information at the time it was entered. It may not reflect current conditions at the site.