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San Joaquin County Community Environmental Setting, Impacts,and Mitigation Measures _ Development Department Groundwater and Groundwater Quality of 370 ac-ft/yr because the 10 acres used for the mine's processing plant would not be replanted with agricultural crops. Dry Pit Conclusions. All of the stages of the proposed Project, except for Stage IV-B,would be anticipated to result in a net increase in water consumption compared to baseline conditions(Table 3.H-1). Water use under the proposed _ Project would represent a shift from the use of surface water for baseline agricultural operations to total dependence on groundwater. The water use increment between the premining conditions and Stages I through IV-B may be greater than described because the actual premining consumptive use estimate may be lower than the estimated premining use, which does not consider the quantity of irrigation water that may seep into the ground and recharge the aquifer. — Wet Pit Projected direct water demand for the wet pit operations would be similar to those of the dry pit operations(approximately 380,000 gallons per day). Indirect water demands would include evaporative loss at the pits as they were being mined and evapotranspiration from undisturbed or reclaimed almond crops. To determine the level of impact that might result from these consumptive uses,the amount of water that would be used is described in detail and compared against historical water use in the project area. Premining Period. The premining conditions would be the same as those described under the Dry Pit discussion. Stages I through III. For Stages I through III, consumptive use of water for the aggregate processing,dust control,concrete production, and truck washing would be approximately 425 ac-ft/yr(380,000 gallons per day). This freshwater consumptive use does not include moisture retained in the product(gravel). As mining displaces irrigation-related consumptive use, the overall water budget would reflect a net increase in water use from a low of approximately 370 ac- ft/yr under current conditions to a peak of approximately 1,411 ac-ft/yr during Stage II (Table 3.H-2). For all of these stages, estimated water consumption would range from approximately 947 to 1,411 ac-ft/yr(Table 3.H-2). On-site wells and pumps would supply groundwater for the mining and reclamation operations. Stages IV-A and IV-B. As part of both Stages IV-A and IV-B,North Pits I and — 2 would be reclaimed and returned to agricultural uses. However, under Stage IV-A, only a portion of North Pit 3 (10.2 acres)would be reclaimed, and the ` remainder(24.8 acres)would be used as an agricultural pond. The net consumption of water in the project area during Stage IV-A would decrease from the peak during Stage II and would represent evaporative losses from the agricultural pond and evapotranspiration from the 182 acres of reclaimed and undisturbed land used for agricultural purposes. Estimated consumptive use would be approximately 453 ac-ft/yr,which is approximately a third of the peak mining period use. DeSilva Gates Quarry Project Draft Environmental Impact Report 3.H-12 As osIO&M