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Ms. Margaret Lagoria • • December 5, 2007 Page 3 of 4 conductor casing will be installed to a depth of approximately 150 feet bgs. The annular space of the conductor casing will be sealed using neat cement. The casing seal will be allowed to cure for a minimum period of 48-hours. Following curing, drilling mud present in the conductor casing will be removed and drilling will resume using mud rotary drilling techniques. The boring will be advanced to a depth of approximately 200 feet bgs. The wells will be constructed using two-inch diameter schedule 40 PVC. The well screens will be designed to monitor the deeper water-bearing zone. It is anticipated that the well screens will extend from 160 to 200 feet bgs. The well screen will be constructed using two-inch diameter schedule 40 PVC with 0.020 inch slots. The sand pack will be #2/12 Monterey or equivalent. Bentonite chips will be placed above the sand pack and hydrated, followed by placing a neat cement grout to the surface. Following installation, each well will be developed to produce representative water quality samples. Wells will be developed by pumping, bailing, and/or surging. Well development will continue until the groundwater is reasonably free of sediment. During development, water quality parameters including pH, temperature, conductivity, and turbidity will be monitored to calculate stabilization within 10% of each parameter and ensure that groundwater representative of the aquifer is entering the well. The physical measurements obtained during well purging will be recorded. A minimum of ten well casing volumes of water will be removed from the well during development. Well development field data will be documented on a groundwater monitoring well field sampling form. Following development, the monitoring well will be allowed to recover to within 2 feet of the initial water level prior to sampling or 24 hours, whichever comes first. Following development, the well will be surveyed to a common datum, referenced to mean sea level (msl). Following development, wells will be purged and sampled using standard methods. At least three well casing volumes of groundwater will be removed from the well using a clean submersible pump, TeflonTm bailer or polyethylene disposable bailer. During purging, water parameters including pH, temperature, conductivity, and turbidity will be monitored to calculate stabilization within 10% of each parameter and ensure that groundwater representative of the aquifer is entering the well. After purging, the well will be allowed to recharge to at least 80% of its original capacity prior to sampling. Groundwater samples will be collected using a clean (triple-rinsed) TeflonTm bailer or polyethylene disposable bailer attached to clean string. Samples will be placed on ice for transport to a California certified laboratory for analysis. All non-disposable sampling equipment will be cleaned with a non-phosphate detergent solution, rinsed with tap water, and rinsed a third time with deionized water prior to use. A Chain-of-Custody Record will be initiated in the field to accompany the samples to the laboratory. The groundwater samples will be analyzed for nitrate using EPA Method 300 and possible additional analysis. The Source Group,Inc.