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F BC-20), and a Marl M5T limited access drill rig (for Well BC-18), both equipped with nominal 10.5-inch outside diameter, continuous flight, hollow stem augers. The boring for Well BC-19 was continuously cored from grade to the completion depth. The remaining two borings were sampled at approximate 5-foot intervals using a California modified split spoon sampler lined with 2-inch by 6-inch brass tubes. Samples were collected at five foot intervals from Boring BC-19 and from each of the sampling intervals in Borings BC-18 and BC-20, placed in a re- sealable plastic bag, and allowed to sit in the sun for a minimum of 10 minutes. The head space in the plastic bag was then aspirated through a flame ionization device and the resulting gas concentration, in parts per million, was recorded on the boring log. The lithology encountered in each boring was described following the Unified Soil Classification System and recorded on the field boring log forms. Additional notations such as depth to water, visual or olfactory identification of chemically impacted soil or groundwater, and other significant field conditions were also recorded on the boring logs. Copies of the boring logs are included in Appendix C. One soil sample was collected from each boring, within the capillary fringe zone, for laboratory analysis. Samples were collected by driving a Califomia-modified split-spoon sampling device, lined with three pre-cleaned brass liners, ahead of the drilling augers into undisturbed soil. The brass liners were immediately removed from the sampling device. The ends of the lower-most brass tube were covered with aluminum foil and plastic caps and sealed with plastic tape. The tube was appropriately labeled and stored in a cooler containing crushed ice until being delivered to an analytical laboratory The soil borings were completed as groundwater monitoring wells using 4-inch diameter, schedule 40 polyvinyl chloride, blank, and 0.020-inch factory-slotted casing. Lonestar No. 3 sand was placed in the annulus from the bottom of the borehole to approximately three feet above the top of the slotted casing to act as a filter pack. Approximately three feet of hydrated bentonite pellets were placed above the filter pack to seal the well. The remaining annular space was backfilled with neat cement. Monitoring Wells BC-18 and BC-19 were completed in above ground steel monuments and monitoring Well BC-20 was completed with a flush mounted, water tight, traffic rated well box set in concrete. Well construction details are summarized in Table 1 and on the boring logs included in Appendix C. The top-of-casing elevations were surveyed by a 3-2