
Zipper Geo Associates provided environmental consulting services in response to historical releases of dry cleaning solvents (primarily tetrachloroethylene) at two adjoining tenant spaces in this strip mall located in Bothell, Washington. The purpose of the project was to facilitate a property transaction. Our Remedial Investigation included collecting groundwater samples from eight monitoring wells and assessing the extent of soil and groundwater impacts using new and existing soil and groundwater quality data. Soil and groundwater impacts only slightly exceeded cleanup levels, and were found to be limited to the immediate vicinity of the tenant spaces. ZGA also assessed regional hydrogeologic conditions and current and reasonably likely future land and groundwater uses in the vicinity of the site. These data were used to develop a conceptual site model that included consideration of sources and release mechanisms for contamination at the site, potential human and ecological receptors, and potential routes of exposure for identified receptors. Fifteen remedial action alternatives were evaluated for the Feasibility Study. Alternatives deemed to be not protective, feasible, or appropriate for the subject site were eliminated from further evaluation, except that certain alternatives were retained as a component of other technologies. Those alternatives that were deemed effective, could be implemented with minimal impacts to the community, workers, and the environment and that had a lower cost were retained for further evaluation. Enhanced reductive dechlorination was selected as the most cost effective remedial alternative.