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. 14 May 2004 AGE-NC Project No 96-0235 Page 2 of 5 After recording water level measurements,wells MW-1,MW-2,MW-3, MW-6 (A and B),MW-8 (A and B),MW-9,MW-11 (A and B)through MW-15 (A and B)and EW-2 were purged of standing water utilizing a Waterra inertial pump or a dedicated disposable plastic bailer, between 5 and 59 gallons of water were removed from each of the wells With the exception of well MW-15B, a minimum of 3 casing-water volumes per well was evacuated, well MW-15B was bailed dry prior to evacuating 3 casing-water volumes For the intermediate and deep wells,groundwater was purged from near the top of the water column to remove water trapped within the non-screened interval of the well casings Ground water temperature,pH and conductivity were measured at regular purge- volume intervals using an Oakton water analyzer Field sheets and data are included in Appendix B Purged water was stored on-site in labeled, 55-gallon DOT-approved drums Wells MW-4, MW-5 and MW-7 were not purged and sampled during the first quarter 2004 monitoring event Well EW-1 was destroyed to facilitate over-excavation activities at the former UST Cluster area, well MW-10 was damaged during over-excavation activities conducted during the fourth quarter 2003 and was not sampled . 2 1 2 Collection and Analysis of Ground Water Samples Water samples were collected from each purged well using new disposable plastic bailers after allowing the wells to achieve a minimum 80%recovery of the pre-purge water volume Each water sample was transferred into 40-m1 volatile organic analysis (VOA) vials containing 0 5 ml 18% hydrochlonc acid as a sample preservative and into 1-liter amber bottles without preservative After collection, the samples were properly labeled, placed in a chilled container and transported under chain-of-custody to Cal Tech Environmental Laboratories(CTEL),a State of California Department of Health Services (DHS)-certified analytical laboratory, and were analyzed for • Total petroleum hydrocarbons quantified as (TPH-g) and as diesel (TPH-d) in accordance with EPA Method 8015M, • Benzene,toluene,ethylbenzene and total xylenes(BTEX)and the fuel additives di-isopropyl ether(DIPE),ethyl tertiary-butyl ether(ETBE),methyl tertiary-butyl ether(MTBE),tertiary- amylmethyl ether(TAME),tertiary-butyl alcohol(TBA), 1,2-dibromoethane(EDB)and 1,2- dichloroethane (1,2-DCA) in accordance with EPA Method 8260B 3.4. FINDINGS The hydrocarbon-impact to ground water was quantified by laboratory analysis of the ground water samples Ground water elevation and gradient was determined by utilizing data collected from the field Advanced GeoEnvironmental,Inc