South Park Landfill

SITE BACKGROUND

The South Park Landfill site is generally located at 8100 & 8200 2nd Avenue South in Seattle, Washington in the South Park neighborhood, on the west side of the Lower Duwamish Waterway (see map).
The South Park Landfill site encompasses approximately 40 acres. About 19.4 acres of this property were previously owned by King County. This portion of the property is currently owned by South Park Property Development, LLC. The remaining area consists of the South Recycling and Disposal Station which is owned by the city of Seattle (City), and a portion of the Kenyon Business Park property owned by private parties.

The property was used as a landfill as early as the 1930s. Open refuse burning was a common practice at the site until 1961. Starting in the 1950s, part of the landfill was also used as an auto wrecking yard which continued into the 1970s. The landfill stopped accepting refuse when the City built the South Transfer Station in 1966 to ship trash out of the area.

From 1984 to 1996 King County leased portions of the site to a variety of lessees for storage, mostly consisting of truck storage. In 2006, King County sold its remaining 19.4 acre parcel to South Park Property Development, LLC (SPPD).

Lower Duwamish Waterway Site

The South Park Landfill site is located within the source control study area for the Lower Duwamish Waterway site in south Seattle. The cleanup of the South Park Landfill site may have importance not only for the immediate area, but may also be important for source control for the Lower Duwamish area.

The Lower Duwamish Waterway site is approximately 5.5 miles long and flows into Elliott Bay. This part of the waterway is designated as a contaminated site under both state and federal law. Ecology and the U.S. Environmental Protection Agency (EPA) are working to clean up contaminated sediments and control sources of recontamination in the Lower Duwamish Waterway . The Lower Duwamish Waterway was added to the National Priorities List (Superfund) by EPA on September 13, 2001. Ecology added the site to the Washington State Hazardous Sites List on February 26, 2002.

There are several sites located within in the Lower Duwamish Waterway study area that are being cleaned up by EPA and Ecology under the Model Toxics Control Act (MTCA) and the Resource Conservation and Recovery Act (RCRA).

Click here for more information on the Lower Duwamish Waterway site

Contamination at South Park Landfill site

In the groundwater, the detected contaminants of concern for the South Park Landfill site are:

Trichloroethene
Dichloroethene
Vinyl chloride
Arsenic

Landfill gas is also present at the South Park Landfill site.

Previous Cleanup Work

Environmental investigations began at the site in the mid-1980s. In 1999, King County entered into Ecology’s Voluntary Cleanup Program (VCP) to address contamination on the site, some of which had migrated off the landfill properties. King County, working independently with technical assistance and advice from the VCP, made progress towards defining the nature and extent of contamination associated with the South Park Landfill site. Now the site will be going through Ecology’s formal cleanup process to complete the investigation into the nature and extent of contamination, to assess remedial action alternatives, and to complete the cleanup.

Agreed Order

The proposed agreement, called an Agreed Order, is a legal agreement between Ecology and the owners and operators of the site (known as potentially liable parties, or PLPs). The PLPs for this Agreed Order are the City of Seattle and South Park Property Development, LLC. King County is also a named PLP at the South Park Landfill site but is not a signatory to the current Agreed Order.

The purpose of the Agreed Order is to protect human health and the environment. It ensures that the cleanup happens in a timely manner and according to Washington State’s cleanup law, the Model Toxics Control Act.

The work done under this Agreed Order will be completed based upon the schedule as shown in Exhibit C of the Order.

Under the Current Agreed Order, the city of Seattle and the current property owners, South Park Property Development, LLC will perform a RI/FS and prepare the first draft of the Draft Cleanup Action Plan. The Agreed Order includes the following activities:

The RI/FS will define the nature and extent of contamination associated with the South Park Landfill site, and evaluate any remedial actions necessary to clean up the Site.

The RI/FS Work Plan will compile and analyze past work done at the South Park Landfill site, identify data gaps, and specify what is necessary to complete the RI/FS.

The Draft Cleanup Action Plan will use the findings in the RI/FS to identify a preferred cleanup action and a schedule to remediate the contamination.