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PR-12 Exhibit 71 12 <br />is 3.1 Shallow Sediments <br />Limited ground water occurs in the alluvium, colluvium, and landslide deposits in the SOD area. The saturated <br />alluvium in the SOD area drainages (Dry Fork, Lick Creek, Deep Creek, and north fork of South Prong Creek) is <br />too limited to be considered a viable ground water resource. Two alluvial wells located in the SOD area are <br />installed in the Dry Fork alluvium: the Upper and Lower Dry Fork Alluvial wells. The depth of alluvium at these <br />wells ranged from 23 feet at the Lower Dry Fork Alluvial Well to 30 feet at the Upper Dry Fork Alluvial Well. <br />The width of the alluvial valley floor at both of these locations is less than 100 feet. Based on observations during <br />the drilling and development of these wells, the estimated hydraulic conductivity of the alluvium is about 10-4 <br />cin/sec (0.3 ft/day) (HydroGeo, 2003b). Monitoring data have been collected from these wells since 2003. The <br />locations of these wells are shown on Map 1 and a summary of the well completion data is shown on Table 3. <br />3.2 Bedrock <br />Even though ground water occurs in numerous bedrock horizons in the region, including the Rollins Sandstone, <br />Bowie Sandstone, and Mesaverde Formation, aquifer tests indicate that the water production potentials of these <br />strata are low and they are not considered viable aquifers (CDMG, 2005a). <br />Eight bedrock monitoring wells located in the SOD area are currently being monitored including: SOM-23-H-1, <br />SOM-23-H-2, SOM-23-H-3, SOM-23-H-4, SOM-C-76, 96-2-2, SOM-3E, and SOM-3B. The wells are installed <br />in strata from the B-Seam to above the F-Seam. A summary of the well characteristics is presented in Table 3 and <br />the well locations are shown on Map 1. <br />3.2.1 B-Seam <br />Wells SOM-23-H-1 and SOM-3B are installed in the B-Seam and are currently being monitored. Based on slug <br />tests and observations made during the drilling and development of these wells, the estimated hydraulic <br />conductivity of the B-Seam ranges from 5x10-5 cm/sec (0.14 ft/day) in well SOM-23-H-1 to about 1x10-6 cm/sec <br />(2.3x10-' ft/day) in well SOM-3B. <br />Monitoring data were collected from well SOM-23-H-1-from 1994 to 1998. Monitoring and data collection at <br />this well was re-initiated in 2005. Water quality and water level data were collected in the rising limb and peak <br />flow periods in the spring and summer of 2006, but no data are available for the low flow period in 2006 because <br />the casing is compromised. Monitoring data have been collected continuously from well SOM-3B since 2003. <br />The B-Seam ground water quality data indicate consistently high levels of TDS, iron, and manganese. <br />3.2.2 E-Seam <br />Wells SOM-23-H-2 and SOM-3E are installed in the E-Seam and are currently being monitored. Based on <br />observations made during the drilling and development of well SOM-3E, the estimated hydraulic conductivity of <br />the E-Seam is about 1x10-6 cm/sec (2.3x10-' ft/day). During development activities the flow from SOM-3E was <br />Septeriber 2007 HrdroGeo, Inc. <br />CJ