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21 June 2018 AdvancedGeo <br />AGE Project No. 11-1847 Environmental <br />Page 6 of 8 <br />3.4. IN-SITU AIR SPARGE WELL COMPLETION <br />Each IAS well will be completed as a single-casing well utilizing 2-inch diameter schedule <br />40 polyvinylchloride (PVC) 0.010-inch slotted well screen and blank well casing. Based <br />on geologic conditions and petroleum hydrocarbon impact, a 5-foot length of well screen <br />from 30 to 35 feet bsg is anticipated for installation of each SVE wells. <br />After installing each well casing, a filter pack material consisting of #2/12 Lapis Lustre <br />sand will be added over the screened interval to approximately two feet above the <br />screened interval. <br />A nominal three-foot bentonite seal (coated bentonite pellets) will be placed above the <br />filter pack to minimize the potential for grout penetration into the screened section of the <br />well. The bentonite seal will be formed by pouring bentonite pellets into the annulus and <br />allowing them to settle on the filter pack. The bentonite pellets will be allowed to hydrate <br />for a minimum of one-half hour prior to grouting. <br />The remaining annular space will be filled to the ground surface with a cement grout. The <br />grout mixture will consist of Type I/II Portland neat cement and not more than 6 gallons <br />of water per 94-pound sack of cement. The grout will be placed by pumping through <br />tremmie pipe. <br />A diagram for the proposed construction of IAS wells IAS-1 and IAS-2 is depicted in <br />Figure 10. <br />3.5. SOIL VAPOR EXTRACTION & INSITU AIR SPARGE PILOT TEST <br />An 8-hour SVE and IAS pilot test will be performed at the site. The 8-hour SVE/IAS pilot <br />test will be conducted from wells VW-1 and from IAS-1. The 8-hour pilot test will be <br />conducted at the site utilizing a minimum 21/2-horsepower, regenerative vacuum blower <br />that is rated at a maximum 150 cubic feet per minute. The inlet of the vacuum blower will <br />be directly routed to the VW-1 well head connected by 2-inch diameter PVC piping. The <br />outlet of the vacuum blower will be directly routed through four 400-pound, vapor-phase <br />activated carbon adsorption canisters located adjacent the vacuum blower. <br />Air-tight, 2-inch diameter PVC well caps fitted with attached Magnehelic (Dwyer) vacuum <br />gauges will be attached to observation wells (VW-2 and VW-3) and the induced vacuum <br />will be measured (i.e. inches of water) at these monitoring points. The induced vacuum <br />will be monitored in 30-minute intervals during the pilot test and recorded in inches of <br />water. <br />Additionally, the vapor stream from the extraction well (i.e. VW-1) will be monitored for <br />the presence of organic vapor using the PID. The vacuum applied at the SVE well should <br />cause hydrocarbons in the vadose zone to volatilize and flow into the operated vapor well