Draft Treatability Study in Support of Remediation by Natural AttenuationBuilding 1212 at Fairchild Air Force Base, Spokane, Washington

摘要

This report presents the results of a treatability study (TS) performed byParsons Engineering Science, Inc. (Parsons ES) at Building 1212, Fairchild Air Force Base, Washington to evaluate remediation by natural attenuation (RNA) of dissolved fuel-hydrocarbons in the shallow groundwater. The TS focused on the fate and transport of dissolved benzene, toluene, ethylbenzene, and xylene (BTEX) in the shallow groundwater system at the site. Residual light nonaqueous-phase liquid (LNAPL) present within the vadose zone and phreatic soils serves as a continuing source for the dissolved groundwater contamination. There is no evidence of mobile LNAPL at this site. The site history also is summarized in this report. No previous investigations have been conducted at the Building 1212 site to determine the nature and extent of soil and groundwater contamination. Comparison of BTEX, electron acceptor, and biodegradation byproduct isopleth maps for the Building 1212 site provides strong qualitative evidence of biodegradation of dissolved BTEX compounds.