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<br /> 16,August 2004
<br /> •,` AGE-NC Project No 96-0235 F
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<br /> After recording,water level measurements,wells MW-1,MW-2,MW-3,MW-6(A and B),MW-7,
<br /> MW-8 (A and B),MW-9, MW-11 (A and B)through,MW-15 (A and B) and EW-2 were purged of
<br /> standing water utilizing a Waterra inertial pump or a dedicated disposable plastic bailer,between 5
<br />' and 60 gallons of water were removed from each of the wells,With the exception of wells MW-6B r -
<br /> and MW-15B, a minimum of 3 casing-water volumes per well was evacuated, wells MW-613 and
<br /> MW-15B were bailed dry prior to evacuating 3 casing-water volumes For the intermediate and deep
<br />' wells, ground water was purged from near the top of the water column to remove water trapped ,
<br /> within the non-screened interval of the well casings Groundwater temperature,pH and conductivity '
<br /> W were measured at regular purge-volume intervals using an Oakton water analyzer Field sheets and
<br />' data are included in Appendix B Purged water was stored on-site in labeled, 55-gallon Department ,
<br /> of Transportation (DOT)-approved drums
<br />' Wells MW-4 and MW-5 were not purged and sampled during the Second Quarter 2004 monitoring
<br /> event Well MW-10 was damaged during over-excavation activities conducted during the Fourth
<br /> Quarter 2003 and was not sampled
<br /> 2 1 2 Collection and Analysis of Ground Water Samples
<br /> Water samples were collected from each purged well utilizing the discharge tube of the Waterra
<br /> inertial pump or a new, dedicated disposable plastic bailer after allowing the wells to achieve a
<br />' minimum 80%recovery of the pre-purge water volume Each water sample was transferred into 40-
<br /> ml volatile organic analysis (VOA) vials containing 0 5 ml 18% hydrochloric acid as a sample
<br /> preservative land into l-liter amber bottles without preservative After collection, the samples were
<br /> properly labeled, placed in a chilled container and transported under chain of custody to Cal Tech '
<br /> Environmental Laboratories (CTEL), a State of California Department of Health Services (DHS)-
<br /> certified analytical laboratory, and were analyzed for
<br /> • Total petroleum hydrocarbons quantified as (TPH-g) and as diesel (TPH-d) in accordance
<br /> with EPA Method 8015M,
<br /> • Benzene„toluene,ethylbenzene and total xylenes(BTEX)and,the fuel additives di-isopropyl -
<br /> ether(DIPE),ethyl tertiary-butyl ether(ETBE),methyl tertiary-butyl ether(MTBE),tertiary-
<br /> amyl methyl ether (TAME), tertiary-butyl alcohol (TBA), 1,2-dibromoethane (EDB) and
<br /> 1,2-dichloroethane (1,2-DCA) in accordance with EPA Method 8260B
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<br /> 1 '' Advanced GeoEnvironmental,Inc
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