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contour maps from the District indicate that ground water is currently first encountered at elevations of -10 to -20 feet MSL in the site area. The flow gradient is regionally to the southwest. Water-level data acquired by EMCON during this investigation indicates that current water levels in wells in the area range from elevations of -19 to -27 feet MSL (see Table 2) . The local gradient is very flat over most of the area, but appears to be generally to the west- southwest (see Figure 4) . Actual local flow direction conditions are believed to be influenced by seasonal pumpage of irrigation wells. No springs were identified on site or within 1 mile of the proposed landfill site. The area was inspected by examining aerial photographs and searching for vegetation reflective of springs. B. SITE HYDROGEOLOGY Ground water is found in site wells (G-1, G-2, W-1 , and W-2) at depths ranging from 124 to 156 feet (see Table 2) . Ground water underlying the proposed landfill site occurs under unconfined or partially con- fined conditions within gravelly or silty sands. Static water levels in Wells G-1 and G-2 are higher than levels at which ground water was first encountered during drilling, indicating some limited confine- ment. Boring G-3 was not converted to a well due to (1) lack of a readily recognized water table above a depth of 170 feet (borehole dry overnight) , (2) borehole instability, and (3) use of a mud-rotary drilling system, which concealed or temporarily sealed off water- bearing zones. Depth to ground water beneath the base of the planned landfill ranges from 96 to greater than 118 feet. Capillary rise is estimated to be less than 5 feet. This estimate is based on data in Lohman (1972) correlating the height of capillary rise with the grain size of unconsolidated soil . PJ9 9390206.00D 10