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<br />Sample holes SH-1 and SH-2 were advanced with atwo-man auger within the bermed area <br />to evaluate soil and groundwater conditions adjacent to the ASTs. SI-I-1 was advanced <br />adjacent to the east of the 20,000-gallon diesel tank to a total depth of 3.5 feet below ground <br />surface. Clayey sand was encountered in SH-1 to a depth of 2.8 feet below ground surface <br />vvtlere a clay layer was encountered to a depth of 3.4 feet. From a depth of 3.4 to 3.5 feet, <br />clayey sand was observed in SH-l. Split soil santple SH-1:2.5 was collected from SI-I-1 at a <br />depth of 2.5 feet for laboratory analysis and for field photo-ionizing detector (PID) organic <br />vapor screening. Organic vapors were measured at a concentration of 103 parts per million <br />(ppm) for soil sample SH-1:2.5. <br />Following advancement of SH-1 to a depth of 3.5 feet, groundwater was observed rising in <br />t}te san\ple hole. A grotndwater sample was collected from SH-1 with a dedicated PVC <br />bailer for laboratory analysis. To avoid creating a conduit for groundwater to permeate the <br />observed clay layer, a monitoring well was not constructed at SH-l, therefore, the <br />groundwater sample from this location was collected without undergoing conventional well <br />development and purging procedures. <br />SI-I-Z was advanced adjacent to the east of the 20,000-gallon diesel tank. Clayey sand was <br />encotmtered in SH-2 from the ground surface to the total a depth of 2.5 feet below ground <br />surftce. Split soil sample SH-2:2.5 was collected from SH-2 at a depth of 2.5 feet for <br />laboratory analysis and for field PID organic vapor screening. Organic vapors were <br />measured at a concentration of 235 ppm for soil sample SH-1:2.5. A groundwater sample <br />.vas not collected from sample hole SH-2 because the sample hole did not readily produce <br />ground~vatcr. SH-2 vvas not advanced below a total depth of 2.5 feet to avoid auger <br />penetration of the clay layer observed in SH-1 from a depth of 2.8 to 3.4 feet. Both SH-] <br />and SH-2 were backfilled with hydrated bentonite chips following s~unplc collection. <br />'Che soil and groundwater samples collected from the sample holes, boreho]es, and <br />monitoring wells were temporarily stored in an ice chest maintained at a temperature of <br />approximately 4° Celsius pending transfer to the analyzing laboratory. Appropriate sample <br />chain-of-custody procedures were followed with transfer of the collected samples. The soil <br />and groundwater s~unples were submitted to Envirorunental Chemistry Services (ECS) in <br />Englewood, Colorado for analysis in accordance with USEPA S W-846 for total extractable <br />petroleum hydrocarbons (TEPH) and benzene, toluene, ethylbenzene, and xylenes (BTE3~ <br />by methods 8015 and 8020, respectively. <br />1.l Borelroles <br />Boreholes BH-l0 through BH-16 were advanced upgradient and in the vicinity of the AST <br />system. The boreholes were located to evaluate soil conditions immediately beyond <br />observed staining described above in Section 2.0. The boreholes were advanced to depths <br />of approximately 10 feet below ground surface to allow for subsequent monitoring well <br />installation. Goodson and Associates, Inc. advanced the boreholes with a CME-75® <br />hollow-stem auger rig by continuously driving 1.5-inch diameter split-tube samplers. Soils <br />were collected with the sampling tubes from the boreholes at 2-foot intervals, logged, and <br />ERA1-ROCKY MOUNr~VN, INC. <br />P:\IOOOISWPC1961019ViEPORT.DOC Printed on Rerycled Paper <br />3 <br />