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N 30 July 2008 AGE-NC Project No . 99-0682 Page 4 of 13 2.2. MONITORING WELL INSTALLATION Based upon the analytical results of grab ground water samples collected during the CPT investigation, on 13 and 14 March 2008, two ground water monitoring wells, MW-9 and MW- 11 , were installed on-site and one ground water monitoring well, MW- 10, was installed off-site at 521 East Oak Street. The monitoring wells were developed on 20 and 21 March 2008 and surveyed on 02 April 2008 . The newly installed monitoring wells were sampled on 20 and 21 March 2008 as part of the first quarter 2008 ground water monitoring event at the site; laboratory reports are presented in the AGE-prepared report entitled Quarterly Report - First Quarter 2008. 2 .2. 1 Drilling and Sampling A CME-75 truck-mounted drill rig was utilized to advance soil borings MW9, MW 10 and MW l l to total depths of 70 feet bsg using 8-inch diameter hollow-stem augers . The drill rig and three-man crew were supplied by Mitchell Drilling, Inc. of Eureka, California. Auger returns generated by the drilling were containerized in properly labeled, Department of Transportation (DOT)-approved 55-gallon drums and stored on-and off-site pending proper disposal. Soil samples were collected from all borings beginning at 50 feet bsg at five foot intervals to the total depth of the borings. Soil samples were collected ahead of the drill bit using a California modified 18-inch split-spoon sampler loaded with three pre-cleaned, 2-inch by 6-inch brass sleeves . The number of blows required to advance the sampler over each 64rich increment of the 184rich sampling interval between 50 feet bsg and the total depth of the borings were recorded on the boring logs. After sample recovery, both ends of the middle sleeve were covered with Teflon sheets, capped, and sealed with tape. Sealed sample sleeves were labeled, stored on ice, and transported under chain of custody to CTEL, a CPDH-certified analytical laboratory in Paramount, California. Selected soil samples from borings MW9 and MW 10 were analyzed for the following constituents: • TPH-g and TPH-d in accordance with EPA Method 8015M; • BTEX and the fuel oxygenates MTBE, DIPE, ETBE, TAME and TBA in accordance with EPA Method 8260B; and • Lead scavengers 1 ,2-dibromoethane (EDB) and 1 ,2-dichloroethane (1 ,2-DCA) in accordance with EPA Method 826013 . Advanced GeoEnvironmental, Inc.