SITE INFORMATION AND CORRESPONDENCE

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Ms. McCartney August 11, 2008 Page 2 of 3 locating firm will be contracted, if necessary, to identify any additional on-site utilities not marked by USA. Results of utility locating by USA will be reviewed and the final locations of the monitoring wells will be selected. Groundwater Monitoring Well Installation and Development Activities will include installing three groundwater monitoring wells. The following is a description of the methods that will be employed. Prior to the commencement of drilling activities, the first 5 feet of each borehole will be hand cleared as an extra measure to protect against damage to underground utilities. The soil borings (necessary for well installation) will be drilled to a total depth of approximately 40 feet below ground surface (bgs). Drilling and sampling will be conducted using hollow-stem auger drilling techniques. Soil samples will be collected at 5-foot depth intervals. Visual description of soil samples will include the following information with depth: • percentage of sample recovery; • depth to first encountered groundwater; • grain size classification (USCS; percentages of gravel, sand, silt, and clay); • color (Munsell color chart); • density; • odor; and • degree of moisture. The wells will be constructed using two-inch diameter schedule 40 polyvinyl chloride (PVC). The well screens will be designed to monitor the shallow water-bearing zone. It is anticipated that the well screen for these wells will extend from 20 to 40 feet bgs. The well screens will be constructed using two-inch diameter schedule 40 PVC with 0.010-inch slots. The sand pack will be #2/12 Monterey or equivalent. Bentonite pellets will be placed above the sand pack and hydrated followed by placing a neat cement grout to the surface. Following a 72-hour curing period, the wells will be developed by pumping, bailing and/or surging. During development, water quality parameters including pH, temperature, electrical conductivity, and visual turbidity will be monitored to calculate stabilization within 10%of each parameter and ensure that groundwater representative of the aquifer is entering the wells. A minimum of ten casing volumes of water will be removed from the wells during development. Well development field data will be documented on groundwater monitoring well field sampling forms. Following development, the wells will be surveyed to a common datum, referenced to mean sea level (msl). Soil cuttings, well development water, and decontamination water produced during sampling will be stored onsite in properly labeled containers. Waste will be profiled and transported to an appropriate disposal facility. The Source Group,Inc.