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<. WIWI k Prior to sampling, the well was developed by purging a total of one well casing volume. Develcp-ent volumes were reduced from the five used in Phase I, to one, when it became apparent .� that neither well was capable of yielding significant amounts of water. Development water was periodically monitored for ph and electrical conductivity, and drummed onsite for ultimate disposal pending analytical results. !" A ground water sample from each well was collected immediately after development. Upon collection, groundwater samples were 1a stored on ice, and delivered that day to Anlab, Sacramento, 1s for chemical analyses. V4 4 . 2 LITHOLOGIC SEQUENCE AND FIRST GROUNDWATER Boring logs fcr all three monitor weds are presented in the 1� Appendix. Briefly, the subsurface strata consist primarily. of sandy clays and silty sands of variable moisture content through a depth of 95 feet. &.:4 For MW-1 , both coarsest lithologic units and elevated HNu readings, as shown in Table 4-2 and Figure 4-3, were associated primarily with the depth interval 65--75 ft, and served as the basis for setting the well screen interval at a 14 depth sufficient to intersect this lithologic sequence. It should be noted however, that HNu instrument malfunction Prevented 1,1D readings over the entire boring (during Phase fY 1 ) . Similarly, field evaluation of moisture content did not suggest the need for a shallower screening interval, to the r ons),te geologist. During Phase II, field HNu readings were inconclusive, and were not used in determining screening }� interval. After well completion and development, water level recovered to a depth of approximately 31 feet below around surface (Mv;- �,.� 1 i . Water level was subsequently reneasuzed on July 27, 6 P11, 4-7