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I Site Background Information: Quick Save # 1 Page 3 of 6 and 1 ,420mg/kg of benzene, toluene, ethylbenzene, and xylenes, respectively in boring B 1 -35'. MONITORING WELL INSTALLATION On 17 and 18 March 2004, four soil borings (MWI through MW4) were advanced at the site. A CME-75HT truck mounted drill rig was utilizing to advance 8 .254nch diameter hollow-stem augers to the total depth of each boring. The drill rig and three-man crew were supplied by Cascade Drilling Incorporated of Rancho Cordova, California. Soil samples were collected ahead ofthe drill bit using a California modified split-spoon sampler loaded with three pre-cleaned 2-inch by 6-inch brass sleeves. The samples were collected from the pilot borings at 5-foot intervals, beginning at 10 feet bsg, using a 140-pound hammer to advance the sampler. Generally, an orange-brown, dry, clayey silt (fill material),was encountered from surface grade to approximately 6 feet bsg. Orange brown to brown, dry, silts and clayey silts were encountered from approximately 6 feet bsg to 26 feet bsg. Orange brown to blue grey hydrocarbon stained, slightly moist, clay was encountered from approximately. 26 feet to 36 feet bsg in MW 1 , MW2 and MW3 and from 20 to 24 feet bsg in the area of MW4 . Gray hydrocarbon stained, moist to saturated silty sand was encountered from approximately 36 feet bsg to 53 feet bsg. Saturated soil was encountered at 40 feet bsg,. $ lue, hydrocarbon-stained clay was encountered from approximately 53 feet bsg to 55 feet bsg. Pilot borings MWI and MW3 were completed as ground water monitoring wells using 2-inch diameter PVC casing, with 0.020-inch slotted screen installed from approximately 35 to 55 feet bsg; MW2 was completed in a similar manner with slotted screen installed from approximately 25 to 45 feet bsg; and MW4 was installed in a similar manner with slotted screen installed from approximately 30 to 50 feet bsg. TPH-g was detected in soil samples collected from borings MWI through MW4 at maximum concentrations in each boring of 1 .2 milligrams per kilogram (mg/kg) (MWl40), 2 .9 mg/kg (MW2-45), 5 .7 mg/kg (M W3-45) and 2 .7 mg/kg (MW4-40), respectively. At least one ofthe BTEX constituents were detected in soil samples collected from borings MW 1 through MW4 at maximum concentrations of 0.44 mg/kg (benzene), 0.072 mg/kg (toluene), 0. 12 mg/kg (ethylbenzene) and 0.20 mg/kg (xylenes), respectively. MTBE was detected in soil samples collected from borings MW2 and MW4 at a maximum concentration of 0.31 mg/kg in sample MW2-35 by EPA Method 8260 . No additional analytes were detected at or above laboratory detection limits in the samples analyzed. SOIL VAPOR AND GROUND WATER EXTRACTION WELL INSTALLATION On 16 and 17 August 2005 , four vapor extraction wells (VW- 1 through VW-4) and one ground water extraction well (EW- 1 ) were installed at the site for performance of a ground water pumping Advanced GeoEnvironmental, Inc.