SITE INFORMATION AND CORRESPONDENCE

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documentation was not provided to justify the Post-ROD change from the asphalt cover to the AB cover and institutional controls documented in the ESD. The Final Draft RAR does not indicate that the analytical results obtained through the DDCE were compiled into a report, or how these data were evaluated to justify 1) the change from the asphalt cover to the AB cover, and 2) the reduction in size of the cover. Please provide the DDCE analytical results and associated report as an appendix to the Final RAR. SPECIFIC COMMENTS 6. Executive Summary, last paragraph,Page ES-2: The last paragraph of this section recommends "no further remedial action" for DSERTS 67, even though EPA considers engineering and institutional controls to be remedies. Section 8.1 (page 8-1) of the EPA ROD Guidance ("A Guide to Preparing Superfund Proposed Plans, Records of Decision, and Other Remedy Selection Documents",EPA 540-R-98-031,July 1999) states that "no action" means "no treatment, engineering controls, or institutional controls." The Draft Final RAR, however, proposes engineering and institutional controls (i.e., AB cover, signs, and maintenance) to manage concentrations of manganese that are higher than the risk-based cleanup standard without building the asphalt cover specified in the ROD. The concentrations of manganese left in place at the site represent a potential noncarcinogenic hazard to occupational workers. Therefore, a"no action" alternative does not appear to be appropriate. Please revise the Executive Summary to remove the recommendation for "no further remedial action" for DSERTS 67. 7. Section 2.2, Determination of Cleanup Standards and Future Land Use,Page 2-1: It appears that responsibility for institutional controls is not spelled out in sufficient detail. The second paragraph of Section 2.2 states, "If ownership of the installation is transferred to private or nonfederal entities,restrictive covenants shall be written into the land property deed to prevent schools, playgrounds, hospitals, or housing from being built at the site until COCs [contaminants of concern] are below levels of concern. Cooperation among the DLA [Defense Logistics Agency], the US Army, San Joaquin County, and signatories to the ROD will be required to enact the restrictions on access and land use." We concur that the level of cooperation between the various stakeholders in DDJC-Tracy will be required, and is likely to be sufficient. However, the organization that will be responsible for tracking the potential land use restrictions for DSERTS 67 should be named in the RAR. Please revise the RAR to identify the organization that will be responsible for tracking the potential land use restrictions for DSERTS 67 in anticipation of a change in ownership of the installation. 3