King County will collect groundwater, soil, and vapor samples near a former dumpsite under Pacific City Park in preparation for the Pacific Right Bank Flood Protection Project.

The project’s aim is to substantially reduce the potential for White River flooding in Pacific and improve environmental conditions along that portion of the river.

The sampling is a precautionary measure that is part of a multi-step dumpsite investigation. Sampling completed to date has found no hazardous materials that could pose a health and safety risk to park users.

Some previous groundwater samples showed concentrations of a chemical called vinyl chloride above screening levels used to guide when further investigation or immediate action may be necessary. The Washington State Department of Ecology advised further investigation with additional sampling.

The county will conduct sampling on voluntary basis on private property and public-right-of-way slightly west of Pacific City Park. The process could begin as early as February and take several weeks to install equipment and collect samples. Groundwater sampling will continue for at least a year after additional wells are installed.

Results from sampling will help determine if cleanup and containment is recommended as part of construction of the flood risk reduction project.

This property was used as a dumping ground from as early as 1914 to 1966, until it was filled with soil in the late 1960s. The property was transferred to a city park in 1972.

King County is committed to working with the Department of Ecology under the Voluntary Cleanup Program to investigate potential dumpsite contamination. Signs will be posted near sampling locations for people to learn more about the effort.

King County staff will be available during sampling to answer questions from community members.