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E r1 7 F� pumped at the time and the pumping levels were deeper than the length of the sounder, 300 to 400 feet). These water levels are well below shallow ground-water levels, recovering each winter to an elevation of 45 to 55 feet MSL. Measurement of the water level in the Ponderosa production well has not been possible due to a blocked airline. The airline of the Brown's New production well was repaired in mid-1996, temporarily facilitating water-level measurements from the well. However, the measurements have not been consistent and may indicate that there is a problem with the airline r or its reported length. eThe ground-water elevations and fluctuations observed during the last six years of monitoring illustrate the difference between the shallow and deep zones beneath the monitoring network area. In � n the shallow wells, ground-water elevations have ranged from 76 to 87 feet MSL across the area with generally less than three feet of seasonal fluctuation, indicating the upper zone (above the confining clay) is an unconfined or "water table" aquifer. Alternatively, in the deep wells (i.e., those completed below the base of the confining clay, which is at an approximate elevation of 75 feet below mean sea level), static ground-water elevations have ranged from 17 feet below mean sea level to 55 feet MSL across the area. These ground-water elevations combined with observed fluctuations as great as 40 �i n feet indicate the lower zone is a confined aquifer and that a downward vertical gradient exists between the upper and lower zones. S The direction of shallow round-water flow has generally been to the souuttheast�durin th 11ast:six g g Y g I� 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) illustrate f the shallow ground-water flow direction and minor areal change in ground-water levels between the r, early spring and fall of that year. During 1995, the water table declined to the lowest observed levels by late spring to summer and generally recovered by the fall. Ground-water levels rose very gradually beneath the eastern portion of the area during 1996 and 1997 with a slight shift in flow direction toward the east-southeast and a slight flattening of the gradient beneath the monitored area. r� This change in direction of flow (to a more easterly direction) generally continued into 1998, as seen in the ground-water elevation contour map for May 1998 (Figure 7). During the last year, shallow F © LUHOORFF & SGALMANINI