Laserfiche WebLink
M. Scott Mansholt - 2 - 18 July 2008 <br /> Chevron OVP <br /> Former Tracy Pump Station <br /> SAIC proposed that the site be divided into two separate projects for consideration of future <br /> No Further Action Required determination. One project would include the former pump station <br /> facility, storage tank locations, and the UPRR easement. The second project would include <br /> the offsite parcel, east of the UPRR easement. However, access issues may delay future <br /> characterization work at the second project and SAIC indicated that Regional Water Board <br /> staff assistance may be needed to communicate with the property owner. <br /> Based on our review, Regional Water Board staff has the following comments: <br /> • The lateral extent of affected soil and groundwater onsite has been defined. However, <br /> the vertical extent of affected groundwater onsite needs to be determined. <br /> • We concur that additional borings and sampling are needed offsite and downgradient to <br /> characterize soil and groundwater conditions east, northeast, and southeast of the <br /> property. <br /> • Appropriate laboratory Method Detection Limits should be used when comparing <br /> non-detect results with the applicable ESLs and/or PRGs used for health risk <br /> consideration. <br /> • Once the onsite and offsite soil and groundwater conditions have been delineated, we <br /> will address SAIC's suggestion that the site be divided into two separate projects. <br /> We concur with SAIC's proposal to conduct the additional investigation described above <br /> provided our comments are addressed. Please continue to provide updates to Regional <br /> Water Board staff regarding access to the downgradient property. <br /> By 1 September 2008, please submit the additional soil and groundwater characterization <br /> workplan for the project. <br /> If you have any questions or comments, please contact Dean Hubbard at (559) 445-5179. <br /> c <br /> SHELTON R. GRAY C. DEAN HUBBARD <br /> Senior Engineering Geologist Engineering Geologist <br /> P.G. No. 6357 <br /> Enclosure(s) <br /> cc: Michael Infurna, San Joaquin County DEH, Stockton <br /> Gary Dobler, Tracy <br /> Michael Jenkins, SAIC, Sacramento <br /> CDH/Rstaff\OVP\Tracy PS/rpt/W P/Ju1y2008 <br />