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N � � d Y I Site Background Information - Fernando ' s Place AGE-NC Project No. 00-0769 Page 2 of 4 surface grade (bsg) for the collection of soil samples. Analyzed samples contained concentrations of total petroleum quantified as gasoline (TPH-g) as high as 14, 100 milligrams per kilogram (mg/kg). Additionally, samples were collected from the soil boring for ground water monitoring well MW- 1 , installed on 28 April 1998 . Analyzed samples from MW- 1 contained high concentrations of TPH-g and benzene, toluene, ethylbeneze, and total xylenes (BTEX) to a depth of approximately 50 feet bsg. Four additional groundwater monitoring wells were installed by FE between 08 and 12 March 1999 . Analyzed soil samples collected from monitoring well soil borings contained detectable concentrations of TPH-g to depths as great as 105 feet bsg, and BTEX compounds to depths as great as 120 feet bsg. Between 14 and 21 August 2001 , Advanced GeoEnvironmental Inc. (AGE) advanced six Cone Penetrometer Testing (CPT) borings on- and off-site to depths between 122 and 175 feet bsg. Based on data collected from the CPT borings, AGE identified four potential hydrogeologic units (First Water Zone, Second Water Zone, Third Water Zone, and Fourth Water Zone) . Significant concentrations of TPH-g, BTEX, and 1,2-DCA compounds were detected in grab ground water samples collected from each of the hydrogeologic units. INSTALLATION OF ADDITIONAL MONITORING WELLS Between, 27 August and 10 October 2002, AGE prepared for and advanced seven soil borings for the collection of soil samples and/or the installation of monitoring wells (MW-4 through MW-9). Screen intervals were installed at the following intervals : 20 feet to 40 feet bsg, 115 feet to 120 feet bsg, 141 feet to 146 feet bsg, and 165 feet to 170 feet bsg. Monitoring wells MW-4 and MW-5 were constructed with a fifth screened interval from approximately 193 feet to 198 feet bsg. A total of 28 soil samples were analyzed. The highest concentrations of petroleum hydrocarbon compounds were detected from soil samples collected at between 40 feet and 60 feet bsg, in HU-1 Middle Zone. TPH-g was detected in soil samples collected from soil borings MW-4, MW-5, and B-2 at concentrations as high as 4,500 milligrams per kilogram (mg/kg) (MW4-58), 3,600 mg/kg (MW5-50), and 2,000 mg/kg (132-50). Benzene was detected in soil samples collected from MW-4, MW-5, and B-2 at maximum concentrations of 33 mg/kg (MW4-58), 21 mg/kg (MW5-50), and 20 mg/kg (112-50); toluene was detected at maximum concentrations of 180 mg/kg (MW4-58), 100 mg/kg (MW5-50), and 54 mg/kg (132-50); ethylbenzene was detected at maximum concentrations of 19.5 mg/kg (MW4-58), 30 mg/kg (MWS-50), and 13 mg/kg (B2-50); and total xylenes were detected at maximum concentrations of 224 mg/kg (MW4-58), 182 mg/kg (MW5-50), and 77 mg/kg (132-50). Advancer! GeoEnvironmental, Inc. ,