Lessons Learned from a Dual-Phase Extraction Field Application
A field-scale Dual-Phase Extraction (DPE) system was installed and operated at the Pinellas Science, Technology, and Research (STAR) Center, formerly the U.S. Department of Energy (DOE) Pinellas Plant, in Largo, Florida, from August 1997 through September 1999. The goal of applying the DPE system was to enhance the pump-and-treat remediation of volatile organic compounds (VOCs) (primarily vinyl chloride, toluene, trichloroethene, and 1,2-dichloroethene) from a shallow surficial aquifer at the Pinellas STAR Center 4.5 Acre Site. Initial operating data for the DPE system demonstrated an aggressive groundwater recovery rate; however, influent groundwater contaminant concentrations were less than those experienced with the pump-and-treat system. In addition, multiple issues complicated initial operations. Following numerous system and operational changes, the system responded with consistent on-line time and daily operation; although contaminant recovery rates did not increase.