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28 September 2009 AGE-NC Project No. 98-0440 Page 2 of 4 2.2. WELL COMPLETION Boring MW-13 was completed as a two-inch diameter groundwater monitoring well using PVC well casing with 0.020-inch slotted screen installed from approximately 69 feet to 79 feet below surface grade(bsg)and with blank well casing extended to the surface.The filter pack(No.3 Lonestar sand) was installed from 68 feet to approximately 79 feet bsg. A 3-foot bentonite seal (318-inch pellets) was installed above the filter pack and hydrated for 30 minutes. The well was then grouted to near- surface with portland type II cement,and a water-tight,traffic-rated well box was installed over the well.An as-built well diagram is depicted on the boring log in Appendix D. 2.3. MONITORING WELL DEVELOPMENT On 08 September 2009,monitoring well MW-13 was developed utilizing a steel bailer and a Waterra inertial pump with dedicated%-inch plastic tubing. Ground water was purged from well MW-13 until ground water was visually sediment free.Approximately 110 gallons of water were removed from the well. Ground water temperature,pH and conductivity were measured at regular intervals during purging using an Oakton water analyzer.Field sheets and data are included in Appendix C. Purged water was stored on-site in properly labeled, 55-gallon DOT-approved drums. 2.4. COLLECTION OF GROUND WATER SAMPLES Upon completion of well development activities a water sample was collected from well MW-13 using a Waterra inertial pump and dedicated%-inch plastic tubing.The ground water sample set was transferred into three 40-m1 volatile organic analysis(VOA)vials.After collection,the samples were properly labeled,placed in a chilled container and transported under chain of custody to Cal Tech Environmental Laboratories (CTEL) a State of California Department of Public Health-certified analytical laboratory, for analysis. Each sample was analyzed for: • Total petroleum hydrocarbons quantified as gasoline(TPH-g)by EPA Method 8015M; and • Benzene, toluene, ethylbenzene, and xylenes(BTEX)by EPA Method 8260B. 3.0. FINDINGS Depth to ground water was determined from field data collected on 08 September 2009. The hydrocarbon impact to ground water was quantified by laboratory analytical data. Advanced GeoEnvironmental,Inc.