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v `Nod V Based on field observations, select soil samples from each borehole will be submitted to an O". FLAP-certified laboratory for analysis under chain of custody protocol. The samples will be analyzed for TPH-D under EPA method 8015 (modified), and for BTEX and MTBE under EPA method 8020. At least two soil samples from each borehole will be analyzed: the sample with the greatest PID reading and a sample from the capillary fringe. All sampling equipment will be cleaned with non-phosphate detergent and rinsed with tap and deionized water before and after each sampling drive. Each borehole will be completed to a depth of approximately 22 feet below grade. A monitoring well will then be constructed in each boring (Section 3.3). V 3.3 Monitoring Well Installation Monitoring wells will be constructed using 2-inch diameter Schedule 40 PVC casing with flush threads and 0.010-inch-slot well screen. The well screen will be installed from 8 feet to 22 feet bsg. A filter pack or very fine sand will be placed around the well screen from the well base to 7 feet bsg. A bentonite seal (hydrated in place) will be installed from 5 to 7 feet bsg. The remaining annular space will be filled with concrete and topped with a traffic rated street-box with a watertight bolted lid; each casing will be secured with a locking, expandable cap. A �. graphical representation of planned well construction is depicted in Figure 8. 3.4 Well Development The new monitoring wells will be developed by swabbing and bailing approximately 72 hours after installation. Swabbing will consist of moving a vented surge block or large PVC bailer in up and down strokes, no more than three feet in length, beginning at the top of the screened well casing and progressing to the bottom of the well. The swabbing activity will be performed to draw fine sediments from the screen filter pack and into standing well water, to be removed by hand bailing. A minimum of five static well volumes of water will be removed from the well. The field measured parameters of pH, temperature, conductivity, and turbidity will be monitored. When these parameters have stabilized, the well development process will be terminated. V 3.5 Groundwater Sampling and Analysis �. Prior to sample collection, a minimum of three static well casing volumes will be purged from each well using a new disposable bailer. During the purge process, pH, specific conductivity and V CNCD\04-28/03\SHAREkUST\03-0027.doc 4 L V