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dominance and total dissolved solids concentrations on the order of 760 mg/1, and a tendency for dominance of <br />sodium, calcium and sulfate. <br />• Well data indicates some influence in water quality over the period 1995 to date. When compazed to upstream alluvial <br />well 006-AY-1 9Figure 4j), well 006-AZ-3 (figure 4k) located downstream of discharge site 115, it has exhibited an <br />increasing trend in conductivity (1300 to 1800 umhos/cm) and total dissolved solids (600 to 1500 mg/I) since 1995. <br />This is not as readily apparent in the alluvial wells located downstream of 006-AZ-3. <br />The water quality data from alluvial wells exhibit seasonal fluctuations reflecting recharge of the alluvium during <br />spring runoff. <br />(b) The application shall contain additional information, which describes the recharge, storage, and discharge <br />characteristics of aquifers and the quality and quantity of ground water for the proposed permit and adjacent <br />areas, according to the parameters and in the detail required by the Division. The application shall also <br />provide well locations and reported yields from all wells within the proposed permit and adjacent areas, <br />which are registered with the Office of the State Engineer. <br />Twentymile Park, which includes the proposed permit and adjacent areas, lies within asemi-arid climatic zone with <br />an average annual precipitation of only 16 inches. With the exception of the spring snowmelt, which results primarily <br />in surface runoff, most of the precipitation received is lost through evapotranspiration and sublimation. As a result, <br />the amount of precipitation available for Bound water rechazge is limited. <br />All ground water aquifers in the general area, except the alluvial aquifers, are rechazged by infiltration in outcrop <br />areas. Outcrop areas for the principal Bound water aquifers are shown on the Twentymile Sandstone Potentiometric <br />Surface Map (Map 33). <br />• Bedrock Aquifers <br />The configuration of the potentiometric surface for the Wadge overburden aquifer (Map 13, Twentymile Park <br />Hydrology) indicates the direction of Bound water movement in this unit. Ground water movement is generally <br />oriented perpendicular to the potentiometric contours in the direction of decreasing potentiometric elevation. The <br />map indicates that ground water tends to move from the recharge aeeas at the outcrops of these units near the southern <br />and western margins of Twentymile Pazk Basin toward the center of the basin, reflecting the structural dip of the <br />lithologic units. The general trend of movement in the permit area is to the north and northwest. Discharge from the <br />Wadge overburden to alluvial aquifers and surface streams is believed to occur in the vicinity of the outcrop area in <br />the eastern and northeastern margins of the basin. A major fault zone in this area may be a significant conduit for <br />much of this discharge. <br />Ongoing monitoring and a series of pump tests conducted by various government agencies and independent <br />consultants have delineated characteristics of the Wadge Overburden in the permit and adjacent areas. The pump tests <br />were conducted under a broad range of conditions and varied in duration from 30 minutes to 72 hours. The <br />characteristics of specific intervals within the Wadge Overburden were tested utilizing temporary well packers and <br />monitoring variations in water levels and flows in adjacent observation wells with continuous water level and <br />discharge recorders. <br />Characteristics of the Wadge Overburden determined for specific monitoring wells in the permit and adjacent area are <br />summarized in Exhibit 9, Aquifer Test Data. The highest permeability values for the Wadge Overburden (0.3 and 0.6 <br />ft/day) are calculated from observation well date (wells 006-82-74A and 74C), and may reflect effects of using radial <br />PR 03-06 2.04-25.1 05/07/03 <br />