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The salinity estimates have the same limitations previously expressed for Phase 1 in that the redistribution of pumping necessary to maintain the water table to satisfactory levels in all parts of the Wellton-Mohawk aquifer is not yet known. Such studies are now under way. 3. Phase 3. Completion of work contemplated under Phases 1 and 2 will permit accomplishment of the majority of the objectives listed previously in this report. To provide overall river regulation on the Lower Colorado River and to produce further reduction in peak salinities, additional works identified as Phase 3 are proposed. In Phase 3, it is contemplated that approximately 27 wells, electrical service facilities, a collection system, and an evacuation conduit would be installed or utilized on the east side of the Valley Division of the Yuma Project. Nine of the above wells are existing and are presently being operated by the Yuma County Water Users' Association. These wells now discharge into the Yuma Main Canal and the Yuma drainage system. Under the proposed plan the existing new wells would operate on an unbalanced pumping schedule and discharge into a buried concrete conduit which would terminate in the river section above Morelos Dam. It is anticipated that the well water so collected would contain approximately 1,500 ppm of dissolved solids. At certain times of the year it may be necessary for some of the wells to discharge into the Yuma canal or main drain. At present, the flow of water delivered across the Sonora land boundary near San Luis averages somewhat less than 200 cfs. Under 95Epson Perfection 4870 Photo, 400 dpi, 8 bit, 9,038,336 byte