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23 September 2008 AGE-NC Project No.07-1537 Page 3 of 8 from approximately 30 to 50 feet bsg in shallow wells MW-7 through MW-10, and from approximately 100 feet to 110 feet bsg in well MW-11. A filter pack, consisting of#2/12 Lonestar sand, was installed from approximately 28 to 50 feet bsg in the shallow wells, and from approximately 95 feet to 99 feet bsg in MW-11. A 2-foot bentonite seal consisting of non-coated bentonite chips was installed above the filter pack of the shallow wells and hydrated. A nominal 4-foot bentonite seal consisting of coated bentonite pellets was installed above the filter pack of well MW-11 and hydrated. Wells were then grouted to near the surface with portland cement, and water-tight, traffic-rated well boxes were installed over the wells. As-built well diagrams are depicted on the boring logs in Appendix C. 2.1.4. Well Head Survey On 29 April 2008, a California state-licensed surveying engineer from Baumbach & Piazza, Inc surveyed the location and elevation of monitoring wells MW-7 through MW-11; the global positioning system(GPS)location was surveyed to the nearest 0.1-foot relative to coordinate datum NAD 83(1986)and the elevation at the top of the well casings were surveyed to the nearest 0.01 foot relative to the City of Stockton Bench Mark# 182 at 15.77 feet above mean sea level (MSL). The elevations of wells MW-7, MW-8, MW-9, MW-10 and MW-11 were determined to be 16.70 feet MSL, 16.63 feet MSL, 16.18 feet MSL, 15.96 feet MSL, and 16.48 feet MSL, respectively. Geo-coordinantes (X, Y and Z) files, and GeoMap, were error-checked and uploaded to the State Water Board's Geotracker data base;the confirmation numbers are 4213196277, 5890396595,and 8403063714. A copy of the survey report is included in Appendix D. 2.2. SOIL PROBE BORING ADVANCEMENT On 04 April 2008, AGE advanced one soil boring (B5) utilizing a van-mounted Geoprobe 5400 direct-push probing unit equipped with 1.25-inch probing rods. The Geoprobe advanced the soil probe boring using a hydraulic hammer to drive soil sampling tools to specified depths. Boring B5 was advanced to a depth of approximately 50 feet bsg for the collection of soil samples and a grab ground water sample. The location of soil boring B5 is illustrated on Figure 2. 2.3. SOIL AND GROUND WATER SAMPLE COLLECTION Soil samples were collected at 5-foot intervals beginning at 5 feet bsg to total depth of the boring. Each sample was collected utilizing a 1.5-inch Geoprobe soil sampling assembly loaded with four six-inch stainless steel sleeves.After collection,the ends of the second stainless sleeve was covered with Teflon sheets,capped and sealed with tape.The sleeve was labeled with the sample designation, Advanced GeoEvironmental,Inc.