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6 The direction of shallow ground-water flow has consistently been to the southeast during the last two years with only slight fluctuations of shallow ground-water levels beneath the area. The ground-water elevation contour maps for March and October 1994 (Figures 5 and 6, respectively) I illustrate the shallow ground-water flow direction and areal change in ground-water levels i between the early spring and fall of that year. During 1995, the water table declined to the i lowest observed levels by Iate spring to summer and generally recovered by the fall, as shown in ground-water elevation contour maps for these periods (Figures 7 and 8, respectively). The n ground-water gradient became slightly more shallow during 1995 as water levels to the northwest declined slightly while those to the southeast remained fairly stable. The contour maps were prepared without including the observed water levels from the deep South Tracy 91 or Brown's 41 wells because they are representative of the deep ground water zone. Also, the observed water levels from the Petz well, which is completed in both shallow and deep zones of the underlying aquifer, were not used in preparing the contour maps. The Petz well water levels have been in an intermediate elevation range between those measured in wells solely I completed in the shallow or deep wells, and may represent a "composite" of shallow and deep zone water levels. i Ground-Water Quality ' General mineral analyses of ground-water samples conducted during the last two years indicated 1 that the ground water beneath the area is hard to very hard with intermediate electrical conductivity (EC) and total dissolved solids (TDS) values (Tchobanoglous, 1985), as shown in Table 2. Hardness values ranged from 230 to 360 mg/1 (Figure 9), and EC values ranged from. i 790 to 1,100 umbo/cm with the highest EC values in san-pies from the shallow wells (Figure 10). 4 Samples from all wells were of a similar sodium/calcium quality, but the proportions of major anions varied with aquifer depth. The shallow ground water appeared to be of a bicarbonate/chloride quality, Such as shown by the Hall well analyses (Figure 11), while deep i ground water appeared to be of a bicarbonate/sulfate quality as shown by the Brown's New well analyses (Collins, 1928; Piper, 1953; Hein., 1959) (Figure 12). ® LIJF-UFFFF= C;s il.,Mw1f l!',Ji