Subsurface Interim Measures/Interim Remedial Action Plan and Decision Document for the 903 Pad, Mound, and East Trenches Areas (Operable Unit No. 2). Public comment, Responsiveness summary: Final.

摘要

The Department of Energy (DOE) is pursuing an Interim Measure/Interim Remedial Action (IM/IRA) at the 903 Pad, Mound, and East Trenches Areas (Operable Unit No. 2) at the Rocky Flats Plant (RFP). This MIRA is to be conducted to provide information that will aid in the selection and design of final remedial actions at OU2 that will address removal of suspected free-phase volatile organic compound (VOC) contamination. The Plan involves investigating the removal of residual free-phase VOCs by in situ vacuum-enhanced vapor extraction technology at 3 suspected VOC source areas within OU2. VOC-contaminated vapors extracted from the subsurface would be treated by granular activated carbon (GAC) adsorption and discharged. The Plan also includes water table depression, when applicable at the test sites, to investigate the performance of vapor extraction technology in the saturated zone. The Plan provides for treatment of any contaminated ground water recovered during the IM/IRA at existing RFP treatment facilities. The proposed MVIRA Plan is presented in the document entitled ''Proposed Subsurface Interim Measures/Interim Remedial Action Plan/Environmental Assessment and Decision Document, 903 Pad, Mound, and East Trenches Areas, Operable Unit No. 2, '' dated 20 March 1992. Information concerning the proposed Subsurface IM/IRA was presented during a DOE Quarterly Review meeting held on 07 April 1992 and a public meeting held on 07 May 1992, at the Marriott Hotel in Golden, Colorado. The Responsiveness Summary presents DOE's response to all comments received at the public meeting, as well as those mailed to date to DOE during the public comment period.