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not possible to locate these wells at this time. These monitoring wells will be constructed using Schedule 40, 2-inch diameter flush-threaded PVC casing. The well screen to be used on all monitoring wells will have a 0.020-inch slot size. This slot size was selected by assessing the variability of subsurface conditions and the fact that many of the permeable zones contain silty, fine sands. If hydrocarbons are encountered during drilling, the monitoring well will be completed so that free product can be measured. This will be accomplished by constructing the well such that part of the screen is above the water table. The filter material which surrounds the screen will be a clean, washed medium to coarse sand (Lapis Luster No. 2/1 2). In our opinion, this choice is appropriate for the variety of subsurface conditions expected (clay, silt, fine to coarse sand, and gravel). The seal immediately above the filter material will consist of a one foot-thick plug of 1/4-inch diameter bentonite pellets which will be tremmied into place. The sealant placed above the bentonite pellets will consist of a cement/bentonite mixture of one sack of Type I Portland cement with 4 1/2 to 8 gallons of potable water and up to 4% by volume of powdered Ca-rich montmorillonite clay bentonite. PVC casings and screens will be steam cleaned prior to placement in the bbrings. Any slough or drilling debris will be removed from the borings prior to placement of the well materials. A protective steel casing with a lock will be placed over the PVC well. In addition, all wells will be surveyed to mean sea level and to the California Coordinate System for horizontal position. Further details on borehole and monitoring well design and installation procedures are presented together with information on sample collection and handling protocol in Appendix A. Procedures for ensuring 5-3 inc