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• Eicher, Hedland, & Miller, 1957) to the northeast near the axis of the Nucla-Sagers Wash Syncline at a <br />saddle between northwest and southeast plunging synclinal axes (Umetco, 1995b). <br />This area was little affected by the Uncompahgre- or La Sal-related faulting. The Lumsden fault is the <br />only fault identified within the area. It trends N70°E through the center of Lumsden Canyon (see Map <br />G-2) and dips steeply to the south (Umetco, 1995b). The displacement is estimated to be about 65 feet <br />between the Lost Dutchman and Hubbard portals. To the west, drill data plots suggest that the vertical <br />displacement is on the order of 100 feet. Eicher, et al (1957) show a similar range of displacements of <br />70 to 90 feet on their cross sections. Lateral displacement, if any, has not been determined. The <br />Lumsden fault was reportedly encountered in at least two headings in the Bonanza Mine. Water flow <br />was not observed and thus the Lumsden fault does not appear to be a water pathway (Umetco, 1995b). <br />5. Ground Water and Surface Water Systems <br />The upper 1,000 feet of Beaver Mesa from the Summerville aquiclude up through the Burro Canyon <br />• and lower sandstones of the Dakota Sandstone is an isolated ground water regime consisting of small <br />sandstone aquifers with limited recharge areas (Umetco, 1995b). Figures G3 and G4 show the recharge <br />areas for the mesa in cross-sectional view and plan view, respectively. The Burro Canyon and Dakota <br />hydrologic unit has a recharge area of 5.7 square miles, which is very small but still greater than the <br />total recharge area of the Brushy Basin and Salt Wash combined. These units outcrop in steep areas <br />and have a relatively narrow recharge area due to steep slopes. Because of the small recharge areas, <br />ground water occurrence is limited in extent and size. When considering that the area receives an <br />average of only 20 inches of total precipitation per year, and much of this is lost to evaporation, surface <br />water runoff, and soil and plant retention; there is not much left for recharge into aquifers. <br />Surface water is also limited in extent and volume with Lumsden Creek flowing only intermittently in <br />response to snow melt and major storms (Wright Water Engineers, Inc. (WWE) 1999). There are a <br />number of small stock ponds on Beaver Mesa above the mines (see Map G-1) that are fed by <br />stormwater runoff. The three small springs located in the area (i.e., DP, PR and Lumsden Springs) <br />discharge water into the creek; however, these flows infiltrate into the streambed downstream within a <br />• short distance (typically about'/4-mile or less) (BLM, 1993). DP Spring, with an average flow of about <br />Whirlwind Mine 07 (rev. April 08) G-6 <br />