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A 09 April 2002 AGE-NC Project No. 97-0301 Page 13 of 14 simultaneously to determine effectiveness of SVE and IAS . An internal combustion (IC) driven engine will be used to apply a vacuum on SVE well V W- 1 while wells VW-2, EW- 1 and MW-7 will be utilized as observation points. During the SVE pilot test, SVE operational parameters including soil-gas vapor concentrations, air flow and vacuum measurements will be monitored at %z-hour intervals utilizing Dwyer Magnehelic vacuum gauges and a photo-ionization detector (PID : Thermo Environmental 580A, 10.0 eV; calibrated to isobutylene). A compressor driven unit will be used to I nject air into the subsurface via IAS well AW- 1 while air sparging rate, vapor concentrations, ground water depths and dissolved oxygen will be measured at approximate ''/a-hour intervals from wells EW- 1 , VW- 1 , VW-2, MW- 1 , MW-2, MW-3, MW-4, MW-5, MW-6 and MW-7 . I Soil vapor samples will be collected at 2-hour intervals in Tedlar bags and analyzed for TPH-g, BTEX and MTBE from aDHS-certified laboratory. Soil vapor fieldparameters and analytical results will facilitate the design of an SVE system and will be used to determine a general radius of influence for spacing of SVE wells, selection of an appropriate SVE system and determine feasibility of IAS as a remediation alternative. i 4. 8. IN-SITU OZONE SPARGING PILOT TEST l Ozone spargmg is an in-situ air stripping process utilizing fine bubbles of ozone that will be injected into saturated soil via OW- 1 to extract and decompose dissolved petroleum hydrocarbon constituents. An ozone generator will be utilized to produce gaseous ozone which will be injected into the subsurface via microsparge points. The "microbubbles" (approximately 50 micrometers) will be forced out into the surrounding saturated soil and react with the target analytes, producing carbon dioxide and water. The frequency and duration of ozone injection periods will be be regulated at the ozone generator control box. Initially, operation of the ozone injection systein will be based on the manufacturer' s recommendations. Injection rates, frequency and duration may be adjusted to compensate for site conditions during thepilot test. The ozone sparge feasibilitytest will be performed for approximately four weeks; ground water samples will be collected and analyzed monthly from the existing monitoring well network and the proposed cluster well to evaluate the effectiveness of the ozone sparge system. Grab water samples will be collected at 1 -week intervals for six weeks (four weeks during ozone sparging and two weeks thereafter) from wells EW4 , VW- 1 , VW-2, AW- 1 , MW4 , MW-7 and MW-8 and submitted to a DHS-certified laboratory for the following constituents: • TPH-g/TPH-d/TPH-k/TPH-mo in accordance withEPAMethod 8015 Modified/5030/3550; • BTEX, methanol, ethanol, 1 ,2-DCA, EDB, MTBE, TAME, DIPE, ETBE and TBA by EPA Advanced GeoEnvironmental, Inc.