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2.04.7 <br /> Mesaverde Forration, above the Rollins Sandstone, were interpreted. Both <br /> are characterized as locally discontinuous saturated strata occurring as <br /> perched horizons. One is stratigraphically between the Rollins Sandstone <br /> member and the "C" coal seam, typically 200 ft. below the "D" coal seam <br /> (refer to the potentiometric surface presented on Map 11, Lower Perched <br /> Water Zone). The other, is located above the "D" coal seam (refer to the <br /> potentiometric surface presented on Map 10 Upper Perched Water Zone). <br /> The "D" coal seam is located 400 feet above the Rollins Sandstone and is <br /> separated from the Rollins Sandstone by sandstones, siltstones, clays, and <br /> coal seams. Although no data for permeability or transmissivity of the <br /> saturated portions of the coal bearing member of the Mesaverde Formation <br /> are available within the permit area, the experience by others (Brooks,1983) <br /> suggests that the Mesaverde Formation transmits little water. Mountain Coal <br /> Company reports a yield of 3 gpm from the 245 interval of the Rollins <br /> Sandstone from its monitoring well R-1 (MCC permit section 2.04.7). The <br /> primary (granular) permeability is low due to the lithologic composition of the <br /> sandstone and the secondary (fracture) permeability is not well developed. <br /> Extensive core drilling within this strata shows that fracture zones are not <br />• well developed. Similar observations were made in the Orchard Valley <br /> underground mine by CWI. Fracture zones or zones of lost circulation <br /> during drilling do not appear to extend~from hole to hole. Fracture and fault <br /> zones, although encountered, are not well developed. <br />The groundwater flow direction in the sandstone strata in the coal bearing <br />member of the Mesaverde Formation is from the recharge area near the <br />outcrop of these strata north toward the lower parts of the basin. An <br />interpretation of the potentiometric surface in this water bearing strata is <br />shown on Maps 10 and 11. <br />These were prepared utilizing exploration data obtained from static water <br />measurements from monitoring wells and, geophysical logging and drill logs. <br />A table entitled "Static Water Levels in Exploration Drill Holes" located in <br />Volume III, Exhibit 3, was compiled primarily from geophysical logs run <br />during the exploration process. <br />In some older drill holes on the site, few field records of the type and amount <br />of drilling fluid, casing (if any), and logging activities are available. Although, <br />the drill medium is usually noted on the electric logs (if available). More <br />PR-03 2.04 - 25 - 5/99 <br />