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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 MW5,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 B11-22,B11-23,B12-
<br /> 20, B12-22, B13-6 and B13-10 at a maximum concentration of 2,200 milligrams per kilogram
<br /> (mg/kg) in sample B11-22. TPH-d was detected in samples B11-22, B11-23 and B12-20 at a
<br /> maximum concentration of 3,500 mg/kg 0311-22).BTEX compounds were detected in samples B 11-
<br /> 22, 1311-23, 1311-26, B12-20, B12-22, B12-26, B12-30, B13-6 and B13-10 at maximum
<br /> concentrations of 5.4 mg/kg benzene(B 11-23),86 mg/kg toluene(B 12-20),38 mg/kg ethylbenzene
<br /> (B11-22) and 131 mg/kg total xylenes (B12-20). 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 1311-30,B11-34,Bl 1-42,1311-46,B12-14,B12-26,B12-
<br /> 30,B13-6 and B 13-10 at a maximum concentration of 99 micrograms per liter(µg/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 21.93 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 B11, B12, and B13 at
<br /> concentrations of 5,300 µg/1, 7,900 µg/1 and 6,500 µg/1, respectively. BTEX compounds were
<br /> detected in the groundwater samples collected from the borings at concentrations as high as 330µg/1
<br /> benzene (1312), 670 µg/1 toluene (B13), 330 µg/1 ethylbenzene (B12) 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 GmEnvironmentel,Inc.
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