Fox Ave Building

Cleanup is underway.

In 2012, Ecology entered into an Agreed Order (legal agreement) with the current property owner, Fox Ave Building LLC, to require implementation of the Cleanup Action Plan. The Agreed Order was amended in 2013 to reflect new cleanup levels.  The selected cleanup action includes thermal treatment by electrical resistance heating (ERH), soil vapor extraction (SVE), and bio-polishing by enhanced reductive dechlorination (ERD), followed by monitored natural attenuation (MNA). 

Why this cleanup matters

This site is part of Ecology’s Lower Duwamish Waterway
source control efforts, because it is contributing pollution to the Lower
Duwamish Waterway (LDW) Superfund Site. The 5-mile stretch of the Duwamish
River that flows north into Elliot Bay was added to the Superfund National
Priorities List by the U.S. Environmental Protection Agency (EPA) in 2001. 

The sediments (mud) in the river contain a wide range of
contaminants due to decades of industrial activity and runoff from urban
areas. EPA is leading efforts to clean up the river sediments. 

Ecology is leading efforts to control sources of
contamination from the surrounding land area. The long-term goal is to minimize
recontamination of the river sediment and restore water quality in the river. 

The Fox Ave Building Site is one of several sites that
will be cleaned up as part of Ecology’s Source Control Strategy – controlling
sources of pollution to the river. Contaminants in the soil and groundwater
around the river pose a risk to human health and the environment. They can also
find their way into the river through storm runoff and other pathways. For more
information, visit our Source Control page.

Site history

Seattle Chain and Manufacturing Company
leased the property from King County, from 1918 until 1937 when it
purchased the property. Seattle Chain and successor companies operated coke and
oil fired furnaces and warehouses on the property.

For the next 20 years, ownership of the property changed hands several times.
In 1956, Marian Properties LLC Enterprises bought the property and leased a
portion of it to Great Western Chemical (GWC). GWC operated a chemical and
petroleum repackaging and distribution facility on the property. GWC pumped
bulk product through buried pipes as well as hoses on the surface. The
facility had a number of underground and above ground storage tanks which
stored chemical and petroleum products, including solvents, acids, and lube
oils.

From the 1960s through the 1980s, GWC replaced and upgraded many of their
warehouse structures. Several other companies leased parts of the property
over the years. A number of chemicals and petroleum products were handled
at the Site.

In 2003, Fox Avenue Building LLC bought the GWC property. Cascade Columbia
Distribution now leases the property and uses the warehouse as a chemical
distribution facility.

The groundwater from the Site reaches the Lower Duwamish Waterway,
making it a concern for source control to prevent recontamination of the
Lower Duwamish Waterway Superfund site.


Contamination

Contamination at the site is the result of industrial use since 1918. The contaminants of concern in the soil and groundwater are:

•Chlorinated solvents
•Petroleum hydrocarbons
•Semi-volatile organic compounds (SVOCs)
•Dioxins and furans


Previous cleanup work

In 1989, Great Western Chemical (GWC) closed six underground storage tanks (USTs) in place which still remain under a concrete pad.  The same year, GWC also decommissioned ten other USTs, and removed these from the property in 1990.  As part of an overall remodel, GWC retained the services of Hart-Crowser to provide engineering assistance in the removal of the tanks.

 In 1991, GWC entered into an Agreed Order with Ecology. Under this agreement, GWC agreed to do a Remedial Investigation/Feasibility Study. 

In 1993 GWC finished the Remedial Investigation and Preliminary Risk Assessment
Report (RI/PRA).  More work was done following this report and summarized in a Supplemental Remedial Investigation and Feasibility Study report in 2000.  Previous investigations and cleanup work performed by GWC and Fox Avenue Building since 2000 include:

•Soil and groundwater sampling
•Seep and soil vapor sampling
•Installation of groundwater monitoring wells
•Various other investigations to define the nature and extent of contamination
•Operation of a soil vapor extraction system
•Pilot testing of various remediation technologies, including injections of chemical oxidants into groundwater
•Underground and above ground storage tank removals

In 2009, Ecology entered into an Agreed Order with Fox Avenue Building requiring them to do the following:

•Perform an interim cleanup measure to control the discharge of tetrachloroethylene (PCE) to the Lower Duwamish Waterway. This used Enhanced Reductive Dechlorination (ERD) to
stimulate naturally-occurring bacteria to degrade contaminants

•Perform a pilot test to see how effective ERD may be in degrading contaminants in soils in the source area for the plume

•Do a source area data gap investigation to better identify the measures and cost needed to clean up this area

•Collect air samples to find whether PCE vapors are reaching the office part of the Fox Avenue Building facility. If so, evaluate restarting the existing soil vapor extraction (SVE)
system to control vapor intrusion

•Do a Supplemental Feasibility Study to evaluate cleanup alternatives and enable Ecology to select a cleanup action that will achieve cleanup levels under state law within a reasonable time frame

•Prepare a draft Cleanup Action Plan (CAP) that documents the cleanup action selected by Ecology

The Model Toxics Control Act (MTCA; Chapter 70.105D RCW 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 (see graphic below) over a variable timeline.

A periodic review is conducted every five years following a cleanup action when institutional controls are used as part of the remedy, as required by the Model Toxics Control Act (MTCA). The purpose of the periodic review is to evaluate current site conditions and to ensure continued protection of human health and the environment.


The 2022 Periodic Review concluded:

• Past and ongoing remedial actions appear to have been effective in reducing concentrations of volatile organic compounds in the subsurface, although some groundwater contaminants currently remain at levels exceeding the cleanup levels (CULs) and remediation levels (RLs). Continued groundwater monitoring and implementation of the ongoing remedial action is required by the Cleanup Action Plan (CAP).  The remedy is expected to be protective of human health and the environment once cleanup levels are met; however, the cleanup is still in process.

• Additional groundwater/seep monitoring to assess the current concentrations and potential rebound of chlorinated volatile organic compounds was recommended.  Additional evaluation of ERD performance and an up-to-date bio-polishing injection plan to address current groundwater conditions was also recommended.

•Additional vapor intrusion assessment was recommended.

• The groundwater CULs should be updated to be protective of surface water in accordance with the current state water quality criteria.

•Additional details can be found in the 2022 Periodic Review report.