Whatcom Environmental Services is directing the delineation and monitoring of the dissolved phase groundwater plume (gasoline) as part of a Model Toxics Control Act (MTCA) independent remedial action. The ongoing investigation at the gasoline tankfarm is focused on the collection of groundwater samples from monitoring wells screened in the perched water system. Eleven perched water monitoring wells, including a background well, were installed using a direct-push sampling drill rig.

Whatcom Environmental Services currently conducts semi-annual groundwater monitoring at the site which includes sampling of the monitoring wells using a low-flow sampling procedure. Geographic information systems (GIS) are used to depict changes in groundwater elevation and gasoline concentration contours. The groundwater data indicate significant biodegradation of hydrocarbons downgradient of the spill sources, and groundwater geochemical data trends indicate that monitored natural attenuation is occurring.