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Assuming a recharge area of 7.1 E7 ft= (that area of the Jumbo Mountain Tract from the B-Seam sub-crop on the • north to the divide to the south and the mine plan area from east to westl, this equates to approximately 42 gpm of water available for discharge. The majority of this discharge would recharge deeper hydrogeologic units, and only a fraction would be available for discharge along the outcrops or downdip. Flow or discharge from in the B- Seam can be calculated using Darcys Law in which: ~ = kia where: 0 = flow k = hydraulic conductivity i = hydraulic gradient a = area Assuming a thickness of 25 feet, an outcrop length oT 11,200 feet, a hydraulic gradient of 0.05 ft/it (see Figure 2), and a hydraulic conductivity of 0.016 ftlday Ibased on SG-1 pumping test), the total flow in this seam, toward the outcrop area, is on the order of only 1.16 gpm. This is considered a very low flow rate and reduces the significance of the B-Seam to the overall hydrologic balance. • Rollins Sandstone -The Rollins Sandstone in the direct vicinity of Jumbo Mountain as described in the West Elk Mountain permit aDPlication is part of the Mesaverde Formation and consists of a white to buff, well sorted, fine to medium grained, massive cliff-forming sandstone of a marginal marine origin, ranging in thickness Trom 150 to 300 Teet in the area. It outcrops as cliffs south and west of Jumbo Mountain and is buried by landslide debris on the north side. Dipping at a rate of 4.6° [o the northeast, it underlies the North Fork of the Gunnison River just north of the West Elk Mine site. Outcrop evaluation of the Rollins Sandstones indicates that this unit is highly calcareous with salts occurring along fractures and bedding planes. Groundwater flow mostly occurs along these lectures. In the region, the Rollins Sandstone has been considered a major aquifer because of its aerial extent and potential yielding capability. However, in the direct vicinity of Jumbo Mountain the Rollins Sandstone appears to be hydraulically isolated. To the south and west, the Rollins Sandstone outcrops in the form of cliffs; and to the north and northeast, it discharges into the North Fork of the Gunnison River. Little recharge occurs along the outcrops because of their vertical nature. Recharge is therefore limited to infiltration from direct precipitation and would be expected to be on the same order of magnitude as the B-Seam of 0.5 in/year. The transmissivity of this unit is also considered very low based on two slug tests performed by MCC in the West Elk Mine area. One test was on monitoring well SOM 128-H, which is located in the surface facilities area • 3