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12 November 2010 AGE-NC Project No. 907-1587 Page 3 of 7 1,2-dibromoethane (EDB) and 1 ,2-dichloroethane (1,2-DCA) in accordance with EPA Method 82608. 2.1.2. Well Completions The pilot borings were completed as ground water monitoring wells using two-inch diameter PVC casing with 0.020-inch slotted screen. The screen was installed from approximately 55 feet to 60 feet bsg (MW-1 B, MW-21B, MW-3B and MW-413) and 20 feet to 40 feet bsg (MW-1 A)with blank casing extended to the surface. The filter pack(No. 2/12 Lonestar sand)was installed from approximately 53 feet to 60 feet bsg (MW-1 B, MW-2B, MW-313 and MW-46)and 18 feet to 40 feet bsg (MW-1 A).A minimal 2-foot bentonite pellet plug was then installed above the filter pack and hydrated. The wells were surged to aide in the setting of the filter material. The wells were then grouted to near the surface with portland cement.Water-tight, traffic-rated well boxes were then installed over the wells. As-built well diagrams are depicted on the boring logs in Appendix B. Confirmation for the submitted geowell log files to GeoTracker are: 9406312346, 6771470069, 2901544034, 7428361296, 8787805140. 2.2. MONITORING WELL DEVELOPMENT On 14 August 2010, the five new monitoring wells were developed. The monitoring wells were developed utilizing a dedicated inertia pump. Ground water was purged from each monitoring well until sediment was visibly reduced in the ground water. Approximately 30 and 60 gallons of water were removed from the various wells MW-1A through MW-413. Ground water temperature, pH and conductivity were measured at regular intervals during purging using an Oakton water analyzer. Field sheets and data are included in Appendix C. Purged water was temporarily stored on-site in properly labeled, 55-gallon Department of Transportation (DOT)-approved drums. 2.3. GROUNDWATER MONITORING WELL SURVEY On 24 September 2010, a California state-licensed survey engineer from Morrow Surveying, Inc. (MSI) surveyed the locations of all newly-installed wells (MW-1A through MW-4b)to the nearest 0.01-foot using coordinate datum NAD 83(1986)and vertical datum of the North American Vertical Datum (NAVD88) from global positioning satellite (GPS) observations. The MSI surveying report is presented in Appendix D. Advanced GeoEnviron mental,Inc.