SITE INFORMATION AND CORRESPONDENCE_2004-2014

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Mr. Maurice Benson August 20, 2009 Page 2 to remediate volatile organic compound (VOC) mass responsible for the offsite trichloroethene (TCE) plume west of DDJC-Sharpe. The report should mention the currently active remedial technologies being implemented in the South Balloon (solid potassium permanganate), Central Area (EHC — Integrated Carbon and Zero Valent Iron), and North Balloon (Emulsified Oil Substrate) in an attempt to remediate the persistent source areas. 3. Page 1-1, section 1.0.3; The section discusses the five metal sites recommended for no-further action including the land use control (LUC) remedy for waste left in place above unrestricted use levels. While the analytical data supporting the No-Further Action (NFA) determinations for each respective metal site was thought to be included in previous Remedial Action Reports, the OU2 ROD Amendment should be all encompassing and include the sampling confirmation data and figures showing that the cleanup objectives have been achieved at each "metals" site recommended for NFA. DTSC requests that supporting figures and data be provided for each site recommended for NFA as Appendices to the report and identified in the Introduction section. It is inappropriate to recommend a NFA determination for the metal sites with contamination remaining in place above unrestricted use/unrestricted exposure levels. LUCs are necessary for the metal sites and therefore constitute an action of implementing, maintaining, monitoring, and enforcing the controls to prevent unacceptable exposure pathway to human and ecological receptors. DTSC cannot concur with the determination of NFA when in reality implementing LUCs constitute a remedial action. 4. Page 1-2, Section 1.0.6; This section does an excellent job discussing the ROD Amendment, Administrative Record requirements, and provides a clear understanding for the public of how one obtains access to documents related to the Installation Program at DDJC-Sharpe. 5. Page 1-3, Figure 1-1, Status of Soil Sites, DDJC-Sharpe; The figure depicts sixteen TCE sites at DDJC-Sharpe 'Requiring No Further Action." While most of the TCE.sites recommended for NFA are currently inactive and do not appear to be acting as a persistent source of VOC contamination to groundwater, a set of sites at DDJC-Sharpe do not meet this criteria. Specifically, Sites P-1 E, P-1 G, P-8A, and P-5A currently have innovative technologies in place in an attempt to remediate existing VOC persistent source mass in the saturated soil and groundwater interface.