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0 0 <br /> L &M OPERABLE UNIT- FIRST QUARTER 2014 SITE STATUS, REMEDIAL SUMMARY, AND <br /> GROUNDWATER MONITORING REPORT <br /> Attachment 2 <br /> Page 6 <br /> installed deep off-site wells MW-40 through MW-44 and MW-46. Three <br /> groundwater samples were collected at 117, 128, and 139 ft bgs using a <br /> HydropunchTM sampling device in soil boring SB-7. Results are summarized in <br /> SECOR's report entitled Additional Assessment Report and Work Plan for <br /> Additional Deep Groundwater Zone Assessment dated July 29, 2004. <br /> From March 21 through April 10, 2005, additional assessment activities were <br /> conducted at the Site. Seven B-zone groundwater monitoring wells (MW-47 <br /> through MW-53), one groundwater monitoring well intended to be a C-zone well <br /> (MW-54), and one groundwater monitoring well intended to be a D-zone well <br /> (MW-55) were installed, and three Geoprobe soil borings (GP-1 through GP-3) <br /> were advanced. Results are summarized in SECOR's report entitled Additional <br /> Deep Groundwater Zone Assessment Report, dated May 25, 2005. <br /> From July 13 through July 15, 2005, 16 soil vapor points were installed to monitor <br /> soil gas concentrations over time and determine radius of influence of the <br /> previously installed SVE system. On July 19 and 20, 2005 baseline soil vapor <br /> samples were collected from 12 of the 16 vapor points. The SVE system was <br /> initiated on August 18, 2005 for select wells. The complete scope of work and <br /> results of the soil vapor well installations, SVE start-up, and soil vapor sampling <br /> were summarized in SECOR's report entitled Soil Vapor Well Installation and Soil <br /> Vapor Extraction Start-Up Report, dated November 30, 2005. <br /> From March 21 through March 23, 2006, additional assessment activities were <br /> conducted at the Site in accordance with the Work Plan submitted January 4, <br /> 2006 entitled Work Plan for Additional DPE Feasibility Testing and Expanded <br /> Remedial System Installation. Seven piezometers and one DPE well were <br /> advanced for the purpose of conducting radius-of-influence analysis on several <br /> existing DPE wells. <br /> Pilot testing on DPE wells was conducted between April 4 and April 26, 2006. A <br /> temporary above ground extraction line was installed on DPE-13 as part of these <br /> pilot testing activities. Results from the pilot testing were used to design and <br /> implement remedial system upgrades to better optimize contaminant mass <br /> removal from soil and groundwater beneath the L&M OU. Remedial system <br /> upgrade installation activities were completed during the second quarter 2007. <br /> Beginning on September 1, 2006 SPH is periodically extracted from a select <br /> group of L&M OU monitoring wells that have had consistent SPH thickness over <br /> recent quarters. Extraction is performed on groundwater wells MW-4, MW-10, <br /> ® Stantec <br />