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27 February 2004 <br /> • AGE-NC Project No 95-0141 <br />' Page 2 of 5 <br /> EX-1 Wells MW-6,MW-9B and MW-10B were purged dry prior to evacuating three casing-water <br />' volumes The wells were allowed to recharge prior to sampling <br /> Temperature,pH and conductivity of purged ground water were measured at regular purge Intervals <br />' using an Oakton water analyzer The field data and field sheets are Included In Appendix B Purged <br /> water was temporarily stored on-site In 55-gallon Department of Transportation (DOT)-approved <br /> H-17 storage drums pending proper disposal <br /> 1 <br /> 2 12 Ground Water Sample Collection and Analysis <br /> Pnor to the collection of ground water samples,the depth to ground water was re-measured In each <br /> well to ensure that a minimum of 80% of the Initial water volume had recharged A water sample <br />' was then collected from each well using a new, dedicated, disposable plastic bailer Immediately <br /> upon retrieval,the sample was transferred Into three properly labeled 40-m1 EPA-approved volatile <br /> organic analysis(VOA)vials containing 0 5 ml 18%hydrochloric acid as a sample preservative The <br /> samples were logged on a chain-of-custody form, stored In a chilled container and transported under <br /> chain-of-custody to Cal Tech Environmental Laboratories (CTEL), a California Department of <br /> • Health Services (DHS)-certified laboratory, The ground water samples were analyzed for <br />' 0 Total petroleum hydrocarbons quantified as gasoline (TPH-g) In accordance with EPA <br /> Method 8015 Modified, <br />' 0 Benzene,toluene, ethylbenzene and total xylenes(BTEX) In accordance with EPA Method <br /> 8260B, and <br />' DI-Isopropyl ether (DIPE), ethyl tertiary-butyl ether (ETBE), MTBE, tertiary-amyl methyl <br /> ether(TAME),tertiary-butyl alcohol(TBA), 1,2-drbromoethane(EDB), 1,2-drehloroethane <br /> (1,2-DCA), ethanol and methanol In accordance with EPA Method 8260B <br /> 1 <br /> ' 3.0. FINDINGS <br /> Ground water elevation, flow direction, and gradient were determined from field data collected on <br /> 22 December 2003 The contaminant Impact to ground water was assessed from the laboratory <br /> ' analytical data collected on 22 December 2003 <br /> ' 3 1 GROUND WATER ELEVATION AND GRADIENT <br /> At the time of the December 2003 monitoring event,depths to ground water ranged from 21 10 feet <br /> ' to 22 31 feet below the tops of the well casings (btoc) Ground water elevations at the site ranged <br /> from 13 51 feet below mean sea level (MSL) In well MW-10B5 to 14 74 feet below MSL In well <br /> ' Advanced GeoEnwronmental,Inc <br />