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since pumping started. All have shown some decrease in salinity with time, as shown on Table 10. Since it is a matter of record that freshening of the aquifer has occurred in the brief period during which pumping has been carried on, studies were made to predict the rate at which this would occur in future years. The estimate of the rate of salinity reduction of the pumped water from the Wellton-Mohawk area is based upon the following assumptions: (1) Average drainage-pumping discharge will be 300 cubic feet per second. (2) The salinity was uniform throughout the aquifer at 6,000 parts per million at the time pumping began. (3) The salinity of water passing the root zone on its way to the water table is 2,200 ppm. (4) There will be an interface between the saline water and the new water. There is no mixing of the waters across the interface. (5) The deep percolation loss is equal to the amount pumped. (6) The well casing is perforated only through the gravel portion of the lower aquifer. (7) The actual porosity of the aquifer has not as yet been computed. Therefore, the volume of water is determined on the basis of 30, 35, and 40 percent porosity pending final determination. 52Epson Perfection 4870 Photo, 400 dpi, 8 bi