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• approximately one mile is determined to be between 50 and 60 feet. This is comparable to <br />the 60 foot drawdowns projected in the PHC for the overlying Twentymile Sandstone at a <br />distance of one mile from the location of mine subsidence. No measurable drawdown has <br />been observed in the Twentymile Sandstone. The impacts observed in the Middle <br />Sandstone are comparable to the worst case projections developed for the Twentymile <br />Sandstone. An increase in the dissolved solids in Williams Fork Alluvium Well AVF-3 <br />appears to have leveled off. The cause of this increase is unknown; however, the data <br />indicates that it is not from the mine discharge or from the waste water lagoon. The <br />increased TDS in the 7 North Angle Discharge seen in 1991 remained approximately the <br />same in 1994, averaging about 1000 mg/I. This increase in TDS was due to the <br />accumulation of water in the North Angle Sump location which was able to equilibrate with <br />oxidized rock within old workings and rubbelized rock within subsidence panels. The <br />• maximum concentrations of 1474 mg/I represents this equilibrium concentration. <br />Concentrations decreased in 1994 when the pump has been running. Flow from the #1 <br />Strip Pit spring discharge was within the range observed during 1982 through 1986. Flow <br />from this spring is influenced by both snowmelt and ditch seepage associated with the 7 <br />North Angle discharge. <br />• <br />12 <br />