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' lease y 16 August 2001 AGE-NC Project No. 01-0852 Page 3 of 7 ASTs known to AGE, the former distillation unit, and the known and suspected sumps were analyzed by EPA Method 8015M for gasoline range hydrocarbons and by SW Method 846 8021 for benzene,toluene,ethylbenzene and total xylenes(BTEX).Although not requested,the samples were also analyzed for methyl tert butyl ether (MTBE) by SW846 8021. Selected samples were also analyzed for ethanol by EPA Method 8260B. 3.0. SAMPLING TARGETS As noted above, former ASTs potentially utilized by the gasohol operation, the distillation unit, a suspected and operating sump,the new pond and an old pond were the primary potential sources of contamination targeted for this investigation.The samples were collected from trenches orpotholes advanced with a backhoe, except for one shallow hand-auger boring (HA1-2). The sample designations indicate the method of sampling (T = trench or pothole, HA = hand auger) or the sampling locality(NP =new pond, OP =old pond). The number following the initial designation indicates the specific sampling locality number(T4=the fourth trench).The final digit indicates the approximate sampling depth(T4-5 =Fourth trench at 5 feet below surface grade). Figure 3 shows the sampling localities and the targeted potential sources targeted by the investigation. Four suspected former ASTs (identified ori aerial photograph) formerly located northeast of the warehouse building were targeted by T1, T2, T10 and T11. T10 and T11 were advanced to further investigate low concentrations of hydrocarbons detected in sample T2, which will be reported below. Trenches T3,T 13 and T 14 targeted the'area of the distillation unit utilized for the gasohol operation. The latter tree samples collected to further assess low concentratiAs of hydrocarbons encountered in the T3 sample, as will be reported in the section below. Trenches T4,T16,T17,T18 and T19 targeted the former cooling tower southwest of the distillation unit(Cooling Tower No. 1). The latter four sampling localities were selected to further assess the lateral or horizontal extent of hexavalent chromium detected in a sample from T4,as will be further reported below. T8, T20, T21, T22 and T23 targeted the cooling tower located between the former fermentation room building and the former boiler room(Cooling Tower No.2).Again,the latter four sampling localities were selected to further assess the lateral or horizontal extent of hexavalent chromium detected in a sample from T8, as will also be further reported below. Trench T5 targeted the approximate area of the suspected former sump and T7 targeted the area of the active sump. Trench T12 targeted two or possibly three suspected ASTs northeast of the distillation unit that were identified'on the 1993 aerial photograph. a Advanced GeoEnvironmental,Inc.