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8. Section 1 .2, Post ROD Action Plan; and Table 1-3 , Primary Document Schedule Table 1-3 implies that the following documents will not be submitted for regulatory agency review: the 308 Design Analysis Report (DAR) , the 1008 DAR, and the draft final versions of the Remedial Design Work Plan (RDWP) , the Remedial Action Work Plan (RAWP) , and the Remedial Action Report (RAR) . Only the 608 DAR and draft versions of the other reports are identified for agency review. EPA recommends that DDJC-Tracy provide the 308 DAR for agency review. If agencies have significant design concerns, it will be more cost effective to identify such concerns early on in the design process, rather than to wait until the 608 design. Also, depending on the nature of agency comments on the draft RDWP, RAWP, and RAR, draft final versions of these documents may need to be submitted to the regulatory agencies for review. EPA and DDJC-Tracy can discuss further if these other documents should be considered primary or secondary documents. Section 1.2 and Table 1-3 should be revised to address these concerns. 9 . Section 3 .2.2.3, SWMU 8 Groundwater Remediation, page 3-13 Please modify the text to indicate that if dieldrin is not reported above the aquifer cleanup standard during 1998 and concentrations are not increasing, then "immediate" groundwater remediation is not necessary. However, please indicate that continued monitoring is required, and that groundwater remediation is not completely precluded at the end of 1998. The RI/FS modeling evaluation, as reported in Section 6.3 .7.4.6.5 of the RI/FS, indicated a peak dieldrin concentration of 7.0 ug/L after 30 years. This implies that concentrations observed in 1998 may be exceeded at a later date, and thus there exists a potential future need for groundwater remediation. 10. Section 3 .2.2.4, OU-1 Groundwater Design Data Gaps, page 3-13 Reference to Section 4.3 .2 should be corrected to 4.2.3 . 11. Section 3 .2.2.7, Northwest Corner of Depot Extraction Well; and Figure 3-2, Proposed CPT Wells Extraction well EW048A (Figure 3-2) seems prematurely located considering that additional CPT sampling and monitoring well sampling have yet to be performed. Please modify this section to indicate that the proposed well location and pump tests are based on available data only, and that these may be modified based on the results of further groundwater sampling. 12 . Figure 3-1, Proposed Extraction Wells Figure 3-1 should differentiate between proposed extraction wells which are expected to be installed and proposed extraction wells which may not be installed (i.e. , EW040AU, EW041AU, EW042AU, and EW045AU) , as explained in the text. 4