FREEWAY II STORMWATER SYSTEM ASSESSMENT

Plateau Geoscience Group conducted an assessment of potential sources of iron and aluminum in the stormwater collection system at the Freeway II property in southeast Portland, Oregon. The Freeway property is a large industrial property with several tenants operating a variety of businesses including combinations of mixing, storage, and handling areas and is subject to a 1200-Z General Industrial Stormwater Permit administered by the City of Portland Bureau of Environmental Services. The Freeway stormwater system collects stormwater from across the site via stormwater catch basins, and sloped paved and unpaved surfaces. The storwater is directed to a stormwater collection pond prior to discharge to Johnson Creek. A report was prepared providing conclusions regarding potential sources of contaminants detected in stormwater, and recomendations for system improvement.