Park Lake Homes Maintenance Shop

This site was cleaned up under our Voluntary Cleanup Program, which provides technical help to owners of contaminated sites. The Site No Further Action (NFA) opinion letter was issued by Ecology on August 23, 2024.

This cleanup project was supported by an Independent Remedial Action Grant (IRAG) in 2025 for $74,000 state share (TCPIRA-2325-HiCoHA-00109). IRAGs encourage and expedite independent cleanups by providing funding to local governments that investigate and clean up contaminated sites under Ecology’s Voluntary Cleanup Program (VCP), and decrease the associated costs of cleanup for ratepayers and taxpayers.

The area in White Center that includes the Site was developed in 1943 as a temporary housing complex known as White Center Heights, and consisted of 569 units for workers building warplanes at the nearby Boeing plant in Seattle. The Word War II-era units were removed by the King County Housing Authority (KCHA) in 1963 during construction of the Park Lake Homes affordable housing project that included 1,025 units on a 100-acre tract that included the Site.

Maintenance buildings were constructed during the housing complex renovation (Figure 4). The housing units and associated maintenance buildings were demolished by KCHA in 2005 to construct the present housing development known as Greenbridge, which consists of 165 units in 71 residential buildings. The Site is located within the Greenbridge development.

Site contamination sources included facility maintenance shops with floor drains and dry wells, a 1,000-gallon underground tank (UST) that stored gasoline, a sub-slab hydraulic hoist, and hazardous materials storage (including pesticides).

Following UST removal, groundwater extraction with off-Site disposal was completed, followed by injection of oxygen-release chemicals to treat residual petroleum hydrocarbons.

Approximately 2,600 tons of contaminated soil were also excavated and disposed of off-Site. Confirmation soil and groundwater samples documented successful compliance with state cleanup standards (Model Toxics Control Act (MTCA)) cleanup levels.