In-situ Substrate Addition to Create Reactive Zones for Treatment of Chlorinated Aliphatic Hydrocarbons: Vandenberg Air Force Base

Abstract : This final technical report documents the demonstration of an innovative groundwater remediation technology performed at Vandenberg Air Force Base (VAFB) Site 35 by ARCADIS G&M, Inc. (ARCADIS). The general purpose of the demonstration program was to evaluate the efficacy of the In-Situ Reactive Zone (IRZ)/Enhanced Reductive Dechlorination (ERD) technology in removing chlorinated aliphatic hydrocarbons (CAHs) from impacted groundwater in a range of geologic conditions and CAH concentrations. This site provided an opportunity to evaluate IRZ at a site that was initially highly aerobic with minimal evidence of CAH natural attenuation. Ultimately, the objectives of the demonstration were to demonstrate the ability to remediate contaminants in the subsurface over a relatively short time period (from one to five years in typical full-scale applications) and to gather information that can be used to estimate long term treatment effectiveness, life span and costs. Also important in this demonstration was to show that the degradation of CAHs does not dead-end at undesirable by-products such as cis-1,2- dichloroethene (cis-DCE) and/or vinyl chloride (VC). The primary benefits of IRZ technology include its ease of regulatory acceptance, its in-situ nature and its relatively low cost.