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1 Kristi Shelton <br /> Page 2 <br /> December 17,2008 <br /> iThe three deep groundwater monitoring wells were destroyed in two phases. The 2-inch- <br /> diameter well casings were pressure grouted in place on June 5,2008,by Gregg Drilling and <br /> 1 Testing. The near-surface portions of the 2-inch-diameter PVC well casing and 8-5/8-inch- <br /> diameter steel conductor casings were removed on August 14,2008,by NRC under the <br /> oversight of Gregg Drilling and Testing. NRC destroyed the near-surface portions of the <br /> 1 wellheads by excavating the soils and concrete around the well and protective casings (with <br /> backhoe and jackhammer) to a depth of 3 feet below ground and then cutting off the steel <br /> casings to 2.5 feet below ground. NRC placed concrete in each excavation to approximately <br /> 1 0.5 feet below ground. NRC then restored the excavations by placing dirt (removed during <br /> excavation) on top of the cement. The work was performed under field oversight of <br /> CH2M HILL. SJCEHD was kept informed during the work,and all key field events were <br /> 1 witnessed by an onsite SJCEHD inspector (Margaret Lagorio). <br /> The surface and subsurface materials removed during the well destruction activities were <br /> 1 placed into a roll-off box staged onsite. One composite sample (solid matrix)was collected <br /> on June 5, 2008,for characterization and disposal at Foreword Landfill. The sample was <br /> sent to Alpha Analytical in Sparks,Nevada,for analysis as follows: <br /> 1 Analysis Laboratory Method <br /> CAM Metals EPA Method SW6020 <br /> 1 TPH, Extractable and Purgeable EPA Method SW8015B/DHS LUFT Manual <br /> BTEX EPA Method 8260B <br /> 1 The analytical results are included as Attachment B. NRC transported the waste bin and <br /> well destruction materials to Forward Landfill on October 28,2008. The waste manifest is <br /> included as Attachment C. <br /> 1 Please let me know if you have any questions or require additional information regarding <br /> the destruction of the 10 SVE wells or 3 deep monitoring wells. <br /> 1 Sincerely, <br /> CH2M HIL <br /> 1 <br /> /Y ' 60t <br /> 1 Mark Wuttig,RG <br /> Project Manager <br /> 1 c: Jeff Wong,San Joaquin Environmental Health Department <br /> 1 <br /> 1 ES122006006SC0/MONITORING WELL DESTRUCTION AT HOLT RELEASE SITE_WL769.DOC/083520005/ <br />