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within the permit application (Section 2.04.7(1) and will continue to provide data as new holes are <br />drilled. The following description of ground water was prepared using information within the permit <br />application, information in the Chimney Rock Mine permit application (C-81-023), and site <br />observations by DMG staff. <br />Ground water in the general azea of the mine occurs in the Pictured Cliffs Sandstone, the interbedded <br />and lenticular sandstones and coal seams of the Fruitland Formation, the Quaternary Terrace Deposits <br />and alluvium of the Animas River. <br />The Pictured Cliffs Sandstone is a regional sandstone aquifer which overlies and underlies the lowest <br />coal seam to be mined, the "C" seam. No water wells are presently completed in this aquifer in the <br />general area. Springs along Carbon Junction Canyon are, in part, supplied by discharges from this <br />aquifer, given the outcropping and subcropping of this sandstone in the stream valley. Spring flows <br />in Carbon Junction Canyon vary from seeps of less than a gallon per minute to over five gallons per <br />minute during dry periods in the fall. Flows are expected to vary seasonally, with increased flow rate <br />recorded in spring and early summer. <br />Ground water flow may not be uniform throughout the Pictured Cliffs sandstone. The applicant's <br />consultant had an 18-inch section of core from the Lower Fruitland-Upper Pictured Cliffs transition <br />zone tested in the laboratory. This sample consisted of hard, poorly sorted, clayey, very fine grained <br />sandstone. The porosity of this sandstone averaged 14 percent and had essentially no permeability. <br />This sample, however, represents a relatively small part of the massive Pictured Cliffs Sandstone and <br />may not be representative of its entire cross-section. No exploration drill holes penetrate the entire <br />section of the Pictured Cliffs Sandstone. Regionally, the Pictured Cliffs Sandstone in outcrop is a <br />massive, hard, well sorted, clean, fine to medium grained sandstone (Fassett and Hinds, 1971, and <br />Shomaker, et. al., 1971). This massive section of Pictured Cliffs Sandstone is permeable and could <br />support ground water flows. <br />The interbedded and lenticular strata of the Lower Fruitland Formation support local discontinuous <br />aquifer systems. Water bearing zones were observed at the base of the Lewis ("C) coal zone, 1.3 feet <br />thick; above the Shamrock ("A") coal zone, 96 feet thick; and above the Shamrock rider coal zone, <br />17 feet thick. Two monitoring wells, 17-B and 82-5, are completed in the first two water bearing <br />zones respectively. The water bearing zone associated with [he Shamrock coal overburden was <br />air-lift bailed at about 50 gpm with no measureable drawdown. This indicates that the Shamrock coal <br />overburden may produce significant inflows to the pit. <br />Oakridge Energy, Inc. has applied for and received a well permit to drill and use water from the <br />water-bearing zone associated with the Shamrock rider seam. This zone was encountered in borehole <br />84-2 (see Map 4-2). An estimated yield of 150 gpm was measured in an air lift during drilling. The <br />recharge area is likely restricted [o the outcrop and subcrop of this zone. <br />At the Chimney Rock Mine, about 30 miles east of the Carbon Junction Mine, pumping tests were <br />run on the Lower Fruitland Formation. These pumping tests yielded a value for transmissivity (T) <br />of 210 gallons per day per foot (gpd/ft) and a value for storativity (S) of 1.3 x 10;. These values <br />