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Weldon Church Site Background Information Page 6 of 12 AQUIFER VOLUME TEST On 17 August 2010, two aquifer volume tests were performed at the site. During the shallow aquifer test, a total of 161 gallons of potable water was injected between 5 feet and 12 feet bsg. Approximately 23 gallons of water per foot was injected for an average of 15 minutes resulting in a calculated flow rate of 1.5 gallons per minute (GPM). At the start of the shallow injection test, depth to water was measured in well MW-2 at 6.68 feet below the top of the well casing (btoc). At the completion of the test, depth to water was measured at 6.65 feet btoc. During the deep aquifer test, a total of 233.5 gallons of potable water was injected between 13 and 21 feet bsg. Approximately 30.5 gallons of water per foot was injected for an average of 18.6 minutes resulting in a calculated flow rate of 1.6 GPM. During the test, water injection refusal was encountered at 21 feet bsg when water began surfacing. The aquifer test was terminated at 21 feet bsg and before reaching the proposed depth of 25 feet bsg. At the start of the deep injection test, depth to water in well MW-2 was measured at 6.71 btoc. At the completion of the test, depth to water was measured at 6.71 feet btoc. SOIL VAPOR SAMPLING SEPTEMBER 2010 On 14 September 2010, temporary soil vapor sampling points V-1 through V-5 were installed on-site to assess the potential for soil vapor intrusion. Soil borings V-1 through V-5 were advanced to total depths of 5 feet below surface grade (bsg) utilizing a 3-inch diameter hang auger. Soil samples were not collected during the advancement of the borings. Soil vapor sampling points V-1 through V-5 were completed using 0.75-inch diameter, schedule 40 polyvinylchloride (PVC) casing with 0.020-inch slotted well screen installed from approximately 4.5 to 5.0 feet bsg and with blank well casing extending to the surface. The filter pack was (#2/12 sand) installed from 4 feet to 5 feet bsg. Following the filter pack installation, a mixture of Volclay and water was used to fill the void space from near surface grade to 4 feet bsg. The soil vapor points were completed approximately six- inches above surface grade and capped. On 16 September 2010, two soil borings (V-6 and V-7) were advanced near the former UST area for collection and analysis of soil vapor samples. The borings were advanced utilizing a van-mounted Geoprobe 5400 direct-push probing unit equipped with 1.25-inch probing rods. Soil vapor borings V-6 and V-7 were advanced to approximately 5 feet bsg. Advanced GeoEmironmental,Inc.