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<br /> . On 07 through 09 October 2002, Advanced GeoEnvironmental, Inc (AGE) advanced seven soil
<br /> borings at the site Pilot borings MW5 through MW 10 were completed as ground water monitoring
<br /> wells using two-inch diameter PVC casing with 0 020-inch slotted screen installed from
<br /> approximately 4 feet to 14 feet bsg in borings MWS,MW9, and MW 10 and from approximately 50
<br /> feet to 60 feet bsg in borings MW6,MW7 and MW9 with blank casing extended to the surface EW 1
<br /> was completed as a ground water extraction well using six-inch diameter PVC casing with 0 020-
<br /> inch slotted screen installed from approximately 4 feet bsg to 19 feet bsg
<br /> TPH-g was detected at a maximum concentration of 4,000 mg/kg(MW6-5) BTEX was detected at
<br /> a maximum concentration of 34mg/kg,310 mg/kg, 110 mg/kg and 720 mg/kg,respectively(MW6-
<br /> 5) The fuel oxygenates MTBE and TAME were detected at maximum concentrations of 56 mg/kg
<br /> (EPA Method 8260B) and 2 2 mg/kg in sample MW6-5 TBA was detected at a concentration of
<br /> 0 30 mg/kg in soil sample MW7-5 Additional information can be found in the AGE-prepared
<br /> Monitoring and Extraction Well Installation Report dated 01 November 2002
<br /> On 22 and 23 October 2002, AGE advanced three soil borings at the site to assess the vertical and
<br /> lateral down-gradient extent of MTBE-impacted ground water A total of twenty-four soil samples
<br /> were submitted for laboratory analysis TPH-g was detected in soil samples B 11-22, B 11-23,B 12-
<br /> 20, B12-22, B13-6 and B13-10 at a maximum concentration of 2,200 milligrams per kilogram
<br /> (mg/kg) in sample B 11-22 TPH-d was detected in samples B11-22, B 11-23 and B12-20 at a
<br /> maximum concentration of3,500 mg/kg(B 11-22) BTEX compounds were detected in samples B 1I-
<br /> 22, B11-23, B11-26, B12-20, B12-22, B12-26, B12-30, B 13-6 and B13-10 at maximum
<br /> concentrations of 5 4 mg/kg benzene(1311-23),86 mg/kg toluene(1312-20), 38 mg/kg ethylbenzene
<br /> (B 11-22) and 131 mg/kg total xylenes (B 12-20) MTBE was detected by EPA Method 8260B in
<br /> samples B13-6 and B13-10 at concentrations of 0 5 mg/kg and 0 038 mg/kg, respectively In
<br /> addition,MTBE was detected in samples B 11-30,B 11-34,B 11-42,B 11-46,B 12-14,B 12-26,B 12-
<br /> 30,B 13-6 and B 13-10 at a maximum concentration of 99 micrograms per liter(4g/1),in sample B 13-
<br /> 6, utilizing EPA extraction Method 1311 (TCLP)
<br /> Physicochemical analysis of four selected soil samples (B12-26, B12-38, B13-14 and B13-23)
<br /> determined a pH range of between 7 1 and 7 2,nitrate-nitrogen range between 6 and 9 ppm,nitrate
<br /> ion range between 26 4 and 39 6 ppm, ammonia-nitrogen range between 17 and 24 ppm, ammonia
<br /> ion range between 2193 and 30 96, ortho-phosphate range between 34 and 38 ppm and potassium
<br /> range between 56 and 64 ppm
<br /> Microbial enumeration determined the populations of general microbes(heterotropic, nonspecific)
<br /> at(12 1 to 17 8) x 105 and specific microbes(gasoline/diesel specific) at(2 4 to 3 5) x 105, specific
<br /> microbes comprised between 16 88% and 19 83 % of the microbe population
<br /> TPH-g was detected in the ground water samples collected from borings B 11, B 12, and B 13 at
<br /> concentrations of 5,300 µg/1, 7,900 µg/1 and 6,500 µg/l, respectively BTEX compounds were
<br /> detected in the ground water samples collected from the borings at concentrations as high as 330µg/1
<br /> benzene (B 12), 670 µg/1 toluene (B 13), 330 µg/1 ethylbenzene (B 12) and 1,520 µg/1 total xylenes
<br /> (B 12) Fuel additives, including MTBE,were not detected at or above laboratory reporting limits in
<br /> Advanced GeoEnvironmental,Inc
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