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04 November 2008 <br />AGE-NC Project No. 02-0926 <br />Page 3 of 5 <br />Borings VW1 and VW2 were completed as soil vapor wells using 2-inch diameter polyvinylchloride <br />(PVC) casing with a 0.030-inch slotted screen installed from 10 feet to 35 feet bsg. Filter pack <br />(coarse aquarium gravel) was installed from total depth to approximately one to two feet above the <br />slotted screen, and a nominal 1 to 2-foot bentonite plug was installed above the filter pack and <br />hydrated. <br />The wells were then grouted to near the surface with Type II Portland cement, and water-tight, <br />traffic-rated well boxes were installed over the wells. As-built well diagrams are depicted on the <br />boring logs in Appendix B. <br />2.4. WELL DEVELOPMENT <br />On 24 July 2008, monitoring wells MW-5 and MW-6 were developed; off-site well MW-4 was <br />developed on 29 September 2008. Monitoring wells were developed by an AGE representative, in <br />accordance with AGE's monitoring and sampling procedures provided in Appendix C. Groundwater <br />was purged from each monitoring well until purge water was visually sediment-free; between 30 and <br />55 gallons of water were removed from each well. Purged ground water was containerized in <br />properly labeled, DOT-approved 55-gallon drums and stored on-site. Monitoring well development <br />field logs are provided in Appendix D. <br />Ground water samples from new monitoring wells will be collected during the monitoring event <br />following installation. <br />2.5. WELL HEAD SURVEY <br />On 10 September 2008, a California state-licensed surveying engineer from Morrow Surveying <br />surveyed the location and elevation of all monitoring wells; the global positioning system (GPS) <br />location was surveyed to the nearest 0.1-foot relative to coordinate datum NAD 83 (1986), and the <br />elevation at the notch in the top of the well casing was surveyed to the nearest 0.01-foot relative to <br />NAVD 88 from GPS observations. The elevations of monitoring wells MW-4, MW-5, and MW-6 <br />were determined to be 18.18 feet above mean seal level (MSL), 18.58 feet above MSL, and 18.53 <br />feet above MSL, respectively. Geo-coordinantes (X, Y and Z) files, and GeoMap, were error- <br />checked and uploaded to the State Water Board's Geotracker data base; the confirmation numbers <br />are 9475872218, 5371550619, and 7916905283. The surveying report is presented in Appendix E. <br />Advanced GeoEnsironmental, Inc.