ARCHIVED REPORTS_XR0003804 - Laserfiche WebLink

Home Browse Search

• 24 May 2005 AGE-NC Project No 98-0448 iPage 4 of 9 i In order to monitor the efficiency of hydrocarbon removal, 1) the SVE air flow of the influent stream was monitored routinely utilizing an organic vapor analyzer(OVA)equipped with a photo- ionization detector (PID Thermo Environmental 580B, 10 0 eV, calibrated to isobutylene), and i 2) influent air flow vapor stream sample was collected from sampling ports installed upstream (influent)ofthe vacuum blower and analyzed Field measurements were recorded at regular intervals and are summarized in Table 6 i 32 IN-SITU AIR SPARGING SYSTEM PROCEDURES iBetween December 2004 and March 2005, the IAS system utilized a 71/2 horsepower, Westward (model no 5Z639) electric air compressor to infect air beneath the water table From the outlet of i the air compressor,a manifold network of one-inch diameter,schedule 80 PVC piping was installed underground to the well heads at IAS wells AW-1 through AW-4(screened 25-30 feet),AW-5 (30- 35 feet) and IAS well MW-413 (screened 45-50 feet) A Wilkerson oil filter (model no M18) and iWilkerson air pressure regulator(model no R28)are installed at the outlet of the air compressor for added controls, Wilkerson air pressure regulators (model no R18) are installed at each IAS well i• head to enable independent control over the varying pressures required to displace water within each air sparge well casing, resulting in continuous air sparging in the IAS network system i Generally,air pressure was discharged at shallow screened IAS wells AW-1 through AW-5 between 5 and 8 pounds per square inch (psi), and to deeper screened well MW-4B between 13 and 15 psi A liquid-filled, air-gauge was installed at each of the above well heads to monitor air pressure 1 3 3 COLLECTION AND ANALYSIS OF VAPOR EXTRACTION AIR FLOW SAMPLES iA total of three extracted air flow vapor samples were collected on 18 January, 16 February and 08 March 2005 from the influent stream of the regenerative vacuum blower unit to measure iconcentrations of hydrocarbon vapor The samples were collected in Tedlar bags utilizing an electric air-vacuum pump i Following sample collection,the samples were properly labeled, placed in a covered container and transported under chain of custody to a DHS-certified laboratory for analysis Each sample was analyzed within 72 hours of collection for TPH-g and BTEX/MTBE in accordance with EPA iMethods 8015M Modified and 8021, respectively 1 IAdvanced GeoEnvironmental,Inc