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the SPDSS Groundwater Hydrobase-compatible database. This procedure was used to assure <br />quality for all data added to the database. <br />3.0 Results <br />The following sections discuss the data analysis and mapping results for aquifer configuration <br />of the South Platte Alluvium Region. The aquifer bottom elevations, groundwater level <br />elevations, ground surface elevations, and saturated thickness grids will be provided to the <br />CWCB in ArcGrid format as part of this TM. Additionally the picks presented in Figure 2 will <br />be provided in shapefile format. <br />3.1 Aquifer Bottom Elevations <br />Figure 7 presents the grid and contours for the aquifer bottom elevations of the alluvium. As <br />discussed in Section 1.2, the grid was created by digitizing contours from various reports, <br />merging the contours together, modifying the contours based on new pick data, exploding the <br />contours to points, gridding the points, and then limiting areas of the grid exceeding ground <br />surface to ground surface. The color fill grid shows generally how the elevations change <br />throughout the region. The bottom elevations in Division 1 range from a low of 3,254 feet near <br />Julesburg at the state line to a high of 7,045 feet near at the southern end of the Kiowa Bijou <br />designated basin. The bottom elevations in Division 2 range from a low of 5,486 feet at the <br />outlet of the Upper Black Squirrel Creek drainage to a high of 7,044 feet in the north end of <br />Upper Black Squirrel Creek drainage. Also shown are contours in intervals of 50 feet, which <br />show the center of the paleochannels, as indicated by the v-shaped contours. The bottom of the <br />alluvium is sufficiently characterized as depicted in Figure 7 to begin development of a <br />groundwater model. <br />3.2 Groundwater Level Elevations <br />Figure 8 presents the grid and contours for the groundwater elevations in the alluvium. The <br />gridding and contouring methods are discussed in Section 1.2 and summarized in Section 3.1. <br />For the purposes of this study, the water table surface was used to define the saturated <br />thickness. The groundwater elevations in Division 1 range from a low of 3,415 feet near <br />Julesburg at the state line to a high of 6,902 feet near the southern end of the Kiowa Bijou <br />designated basin. The groundwater elevations in Division 2 range from a low of 5,557 feet near <br />the outlet of the Upper Black Squirrel Creek drainage to a high of 6,718 feet in the north end of <br />the Upper Black Squirrel Creek drainage. Also shown are contours in intervals of 50 feet, which <br />highlight the geometry of the water table. As discussed in Section 1.2.4, the historical <br />groundwater surface shown is indicative of current groundwater levels. <br />3.3 Ground Surface Elevations <br />Figure 9 presents the ground surface elevation data from the USGS 30-meter NED. For the Task <br />48 modeling, ground surface will be used to define the upper limit of the alluvial aquifer. <br />Within the alluvial extent, ground surface elevations in Division 1 range from 3,427 feet to 7,123 <br />feet, while in Division 2 they range from 5,580 feet to 7,301 feet. <br />3.4 Saturated Thickness <br />Figure 10 presents the saturated thickness of the South Platte Alluvium calculated as the <br />difference between the groundwater level and bottom of alluvium grids. Saturated thickness <br />SPDSS Phase 3 Task 42.3 TM -Final 12 <br />11/30/2006 <br />