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Exhibit 71 Hydrologic Characterization South of the Divide Area and Monitoring Plan 11 <br />• 3.1 Shallow Sediments <br />Limited ground water occurs in the alluvium, colluvium, and landslide deposits in the SOD area. The <br />saturated alluvium in the SOD area drainages (Dry Fork, Lick Creek, Deep Creek, and north fork of South <br />Prong Creek) is too limited to be considered a viable ground water resource. Two alluvial wells located <br />in the SOD azea are installed in the Dry Fork alluvium: the Upper and Lower Dry Fork Alluvial wells. <br />The depth of alluvium at these wells ranged from 23 feet at the Lower Dry Fork Alluvial Well to 30 feet <br />at the Upper Dry Fork Alluvial Well. The width of the alluvial valley floor at both of these locations is <br />less than 100 feet. Based on observations during the drilling and development of these wells, the <br />estimated hydraulic conductivity of the alluvium is about 10~ cm/sec (0.3 ft/day) (HydroGeo, 2003b). <br />Monitoring data have been collected from these wells since 2003. The locations of these wells are shown <br />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 <br />Sandstone, Bowie Sandstone, and Mesaverde Formation, aquifer tests indicate that the water production <br />potentials of these strata are low and they aze not considered viable aquifers (CDMG, 2005a). <br />Eight bedrock monitoring wells located in the SOD area aze currently being monitored including: SOM- <br />23-H-1, SOM-23-H-2, SOM-23-H-3, SOM-23-H-4, SOM-C-76, 96-2-2, SOM-3E, and SOM-3B. The <br />wells are installed in strata from the B-Seam to above the F-Seam. A summary of the well characteristics <br />is presented in Table 3 and the well locations are shown on Map 1. <br />3.2.1 B-Seam <br />Wells SOM-23-H-1 and SOM-3B ate installed in the B-Seam and are currently being monitored. Based <br />on slug tests and observations made during the drilling and development of these wells, the estimated <br />hydraulic conductivity of the B-Seam ranges from 5x10.5 ctn/sec (0.14 ft/day) in well SOM-23-H-1 to <br />about 1x10" cm/sec (2.3x10-3 ft/day) in well SOM-3B. <br />Monitoring data were collected from well SOM-23-H-1-from 1994 to 1998. Monitoring and data <br />collection at this well was re-initiated in 2005. Monitoring data have been collected continuously from <br />well SOM-3B since 2003. The B-Seam ground water quality data indicate consistently high levels of <br />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 aze currently being monitored. Based <br />on observations made during the drilling and development of well SOM-3E, the estimated hydraulic <br />conductivity of the E-Seam is about 1x10"6 cm/sec (2.3x10"3 ft/day). During development activities the <br />Apd12006 AydraGen, lne <br />