SITE INFORMATION AND CORRESPONDENCE FILE 2

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Messrs Trommer and Ln. 19 June 2008 Preliminary Five-Year Review Letters Page 3 of 7 Various Sites 1645 Cherokee Road. • The CUF concurs with the EHD directive and work plan approval for additional site assessment and recommended conducting regular quarterly monitoring and uploading existing data to GeoTracker; the EHD has directed these actions. 440 Charter Way, W. • The CUF has recommended that the EHD issue directives to assess remedial groundwater technologies and implement active groundwater remediation without delay. The EHD intends to issue such directives after the second monitoring event that includes these new wells has been reported and reviewed to better tailor the directives to site conditions. 2905 and 2908 Benjamin Holt Drive. • The CUF has recommended that the remediation systems continue to operate to achieve WQOs in a timely manner. The sites are not currently under active remediation, the consultant notes in their reports that the remediation method is natural attenuation, which the EHD has not approved as the appropriate remediation method at this time. A municipal_well is within 300 feet of one of the sites and in the past the municipal well has been impacted by the plume; monitoring wells down-gradient of the municipal well are currently impacted. The. monitoring wells on the Chevron station were destroyed during a station rebuild and were later reinstalled; with receipt and review of the fourth quarterly monitoring event on the new wells, the EHD plans to review all data and issue directives related to remediation requirements. 2050 Fremont Street, E. The CUF has recommended that the EHD direct the RP to define the extent of contamination, assess remedial technologies, and implement active remediation that will achieve WQOs in a timely manner; the EHD agrees with these recommendations and notes that directives have been issued. 602 California Street, N. • The CUF has recommended that the EHD direct assessment of remedial technologies and implement active remediation without delay; the EHD agrees with these recommendations. A feasibility study has been directed, SVE has been tested and found to be an effective technology to,remediate impacted soil and the EHD approved preparation of.a work plan to install an SVE system; the consultant then recommended DPE without a technical justification. As a technical justification has not been provided after having been requested in- writing, nwriting, the EHD has issued a directive to submit a work plan for SVE. A report of findings for recently installed monitoring wells is pending. 1112 Harding Way, E. • The CUF has recommended that the EHD direct the RP to assess remedial technologies that may achieve WQOS more rapidly; the EHD agrees with this 5-Year Review Comment Letter 061908.doc