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V 19 October 2012 AGE-NC Project No. 97-0312 Page 17 of 22 6.3. ANALYTICAL RESULTS OF EIGHT-HOUR HVSVE PILOT TEST SAMPLES TPH-g were detected in the soil-vapor samples at concentrations ranging from 28,000 micrograms per liter(Ng/1)to 34,000 pg/l; benzene, toluene, ethylbenzene and total xylenes were detected in the soil-vapor samples at concentrations as high as 490 pg/I benzene, 1,400 tag/I toluene, 380 pg/I ethylbenzene and 1,500 pg/I total xylenes; these values calculate to nearly 9,500 parts per million by volume (microliter per liter of soil vapor)for TPH-g, 150 ppmv benzene, 370 ppmv toluene, 86 ppmv ethylbenzene and 330 ppmv xylene. Additionally, TPH-d were initially detected at 840 milligram per cubic meter (mg/m3), while concentration concluded at 1,100 mg/m3 (parts per billion: ppb). 6.4. MASS CALCULATION OF RECOVERED PRODUCTS On 18 February 2010, a HVSVE pilot test was operational for 8 hours. The average analytical results (30,000 pg/1) of the HVSVE soil vapor samples, average flow rates (45 scfm) and the operational period (8 hours) were used to calculate the approximate mass of extracted gasoline during this period. During the operational period, the combined mass of SVE hydrocarbons extracted by SVE operations was calculated to be approximately 40 lbs of gasoline or equivalent to a volume of approximately 6.439 gallons of gasoline. 7.0. EXTENDED HVSVE PILOT TEST On 14 February 2011, an extended duration, HVSVE pilot test was conducted at the site using vapor well VW-1 (screened 10 feet to 30 feet) as the extraction well. The proposed operational duration was five days. The same HVSVE system design was used for the five day pilot test as previously utilized ,., for the eight-hour test. AGE extracted soil-vapor from on-site soil vapor extraction well VW-1 (4-inch diameter well screened 10 to 30 feet bsg). The soil vapor matrix was collected into an entrainment liquid separator, which removes the majority of the condensate collected during the vacuum extraction process. The operation of the high vacuum SVE unit was performed according to DPE unit manufacturer specifications. The HVSVE vacuum pump, under standard temperature and pressure, was capable of producing a maximum vacuum of 28-inches Mercury (Hg) with a capacity of 100 SCFM. HVSVE was accomplished from well VW-1 by installing a 2-inch diameter PVC pipe from the top of VW-1 through a flow meter and to a 2-inch diameter flexible reinforced rubber hose connected to the HVSVE unit. Once the HVSVE was operational, the hydrocarbons in soil-vapor and volatilized hydrocarbons were processed through an electric heated ti Advanced CeoEnvironmental,[ne. 4r