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<br />1. Quanfitanvr Impacts of Mining <br />49,950,279 ft3 x 7.4805 gal/fC' = 373,653,062 gallons <br />Flooding occurred over approximately 4 years, at 365 days per year, 24 hours per day and 60 <br />minutes per hour, or over 2,102,400 minutes. <br />1,276,248,741 gallons / 2,102,400 minutes = 177 gpm <br />Mine inflows at New Elk were reported to be 176 gpm during the 1989 survey. This correlation <br />is unexpected as the mine workings typically are not hydraulically connected due to mine <br />configuration and seals. In addition, there may be some upslope workings with trapped air <br />pockets. Portions of the mine may have been left to flood at varying times and rates over the <br />years; mine records are not available to reconstruct events or to establish a flooding history. <br />Basin will commence a monitoring program to estimate current rates of inflow. <br />The 1980 WWL report made a projection that drawdowns of one foot would be seen at distances <br />ranging from 4100 - 7700 feet from the perimeter of the mine based on varying estimates of <br />vertical leakance. The previous mine inflow analysis indicated that Cases IIB and ]IIB <br />reasonably fit the results observed at the Golden Eagle Mine. Therefore, new estimates of the <br />• drawdown are calculated based on revised vertical leakance values (Table 7). These estimates <br />suggested that one foot of drawdown would be evident from 1.7 to 2.1 miles from the perimeter <br />of the mine. <br /> <br />Concerns about drawdown in the itnmediate adjacent areas was quantified through the <br />observation of depths to water in some holes immediately adjacent to the Golden Eagle Mine <br />(Figures 5 and 7). Actual drawdown in four wells located within 900 feet of the perimeter of <br />the mine have shown drawdowns as much as 175' at a distance of 125' from the perimeter of <br />the mine and 13.6' at a distance of 500' from the perimeter of the mine. Well 218 does not fit <br />the curve and shows a drawdown of 258' at 900' from the perimeter of the mine. This site is <br />surrounded on three sides by mining and is located along the Notch fork of the Purgatoire river <br />in the Picketwire Valley. <br />23 <br />