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r W <br /> 30 April 2005 <br /> . AGE-NC Project No 98-0465 <br /> t Page 2 of 4 v <br /> , <br /> 22 COLLECTION AND ANALYSIS OF GROUNDWATER SAMPLES- <br /> Water samples were collected from each monitoring well using dedicated,disposable plastic bailers <br />' after allowing the well to achieve a minimum 80% recovery of the pre-purge water volume The <br /> samples from each well were transferred into three 40-milliliter(ml)volatile organic analysis(VOA) <br /> t vials containing 0 5 ml 18% hydrochloric acid solution as a sample preservative and one'1-liter <br />' amber bottle without preservative The samples were labeled with the monitoring well designation, <br /> date,time of sampling, and the sampler's initials and transported in a chilled container under chain <br /> of custody to Cal Tech Environmental Laboratories (CTEL), a Department of Health Services- <br /> certified analytical laboratory, for analysis The samples were analyzed for <br /> • Total petroleum hydrocarbons quantified as gasoline (TPH-g) aild diesel (TPH-d) in <br />' accordance with EPA Method 8015-modified, <br /> • Volatile aromatic compounds benzene, toluene, ethylbenzene, and xylenes (BTEX) in <br />' accordance with EPA Method 8260B, and <br /> • Fuel oxygenates MTBE, di-isopropyl ether (DIPS), ethyl tertiary-butyl ether (ETBE), <br /> • tertiary-amyl methyl ether (TAME), and tertiary butanol (TBA) in accordance with EPA <br />' Method 8260B, and <br /> G Fuel scavengers ethylene dibromide(EDB)and 1,2-dlchloroethane(1,2-DCA)in accordance <br />' with EPA Method 8260B <br /> 3.0. FINDINGS ' <br /> Ground water elevation and flow direction were inferred from field data collected on 14 January <br />' 2005,hydrocarbon`impact to ground water was quantified by laboratory analysis of the ground water <br /> h <br /> samples' ' <br /> 1 , <br /> , <br /> , r <br /> 3 1 GROUND WATER GRADIENT AND FLOW DIRECTION ` <br /> The elevation of ground water in each of the monitoring wells was calculated,by subtracting the <br /> depth to ground water from the surveyed casing eldvations (Table 1) Depths to ground water , <br /> averaged 10 11 feet below surface grade (bsg) Ground water elevations at the site ranged from <br /> z 6 84 feet(MW-4)to 7 01 feet(MW-2)below mean sea level (MSL) Ground water elevations at the <br /> adjacent slte,(Sanchez Property)ranged from 4 75 feet(MW-5)to 5 15 feet(MW-6A)below MSL <br />' (Table 1) During this monitoring event, the ground water elevations were within the screened <br /> intervals of the wells <br /> Advanced GeoEnvironmental,Inc <br /> 4 a = <br /> r <br />