Laserfiche WebLink
o . <br /> hood <br /> October 23, 2013 <br /> Mr. Johnny Yoakum GHD Job No.: 03009-10016-37140 <br /> San Joaquin County Environmental DGS Contract#: 3152182 <br /> Health Department Site#: EAR#R09-123 <br /> 1868 East Hazelton Avenue <br /> Stockton, CA 95205-6232 <br /> Re: Workplan for Well Destruction and Site Closure Activities <br /> Former Blue Star, Project Site "L",4040 East Main Street, Stockton, CA <br /> CVRWQCB Case#391140, San Joaquin County LOP Case#1350 <br /> Dear Mr. Yoakum: <br /> GHD Inc. has prepared this Workplan for well destruction and final site closure proceedings to be <br /> performed at the Former Blue Star site located at 4040 East Main Street, Stockton, California (Figure <br /> 1). In an October 21, 2013 electronic correspondence (Appendix A), the Central Valley Regional Water <br /> Quality Control Board (CVRWQCB) concurred with GHD's request for no further action related to site <br /> cleanup and directed GHD to decommission the existing monitoring wells and dispose of the generated <br /> waste. <br /> This Workplan summarizes the proposed scope of work to proceed with the final site closure by <br /> properly destroying the existing groundwater monitoring wells MW-1 through MW-5 (Figure 2). A GHD <br /> field geologist will coordinate and observe the destruction of the monitoring wells in accordance with the <br /> Standard Operating Procedures (SOP) for Groundwater Monitoring Well Destruction outlined in <br /> Appendix B. A copy of the boring logs for MW-1 through MW-5 are provided in Appendix C. GHD has <br /> also included a Site-Specific Health and Safety Plan (Appendix D) that has been prepared to outline <br /> safe working conditions at the site. <br /> MONITORING WELL DESTRUCTION BY DRILLING <br /> The site will be marked and Underground Services Alert(USA)will be notified of the planned work at <br /> least 48 hours prior to drilling to define all utilities in the area of monitoring wells MW-1 through MW-5. <br /> Well destruction will be performed by Woodward Drilling of Rio Vista, California, a C-57 licensed <br /> (#710079) drilling contractor specializing in environmental investigations. <br /> A hollow-stem auger drill rig will be used to destroy the monitoring well. The casing and well <br /> construction materials will be drilled out to 81 feet below ground surface (bgs) for MW-1, MW-2 and <br /> MW-3, and to 75 feet bgs for MW-4, and 78 feet bgs for MW-5 and handled as investigation derived <br /> residuals (IDRs) per GHD's SOP for Groundwater Monitoring Well Destruction (Appendix B). The <br /> augers will be advanced to a depth of one foot below the original well/point boring depth. After removal <br /> of the well casing, sand pack, and seal, the boreholes will be tremie-grouted through the hollow-stem <br /> augers with a cement/bentonite slurry to approximately 2 feet below grade. The surface will be <br /> completed to match the surrounding ground surface. <br /> INVESTIGATION DERIVED RESIDUALS <br /> The well casing, well construction materials, soil cuttings, and groundwater will be handled as IDRs. <br /> The IDRs will be temporarily stored on site in DOT approved drums and/or a covered roll-off bin until <br /> disposal at a permitted facility can be arranged. A composite soil sample will be collected to <br /> GHD Inc. <br /> 3831 N. Freeway Blvd Suite 220 Sacramento CA 95834 USA <br /> T 1 916 372 6606 F 1 916 372 6616 E sacramento@ghd.com W www.ghd.com <br />