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<br />1 <br /> <br /> <br /> <br /> <br /> <br /> <br /> <br />1 <br /> <br /> <br />L <br /> <br /> <br /> <br /> <br />1 <br />and Wildlife refused to grant permission to do so because of the endangered squawfish being <br />planted in the river. WFU has not received WQCD's approval of this plan. <br />The toxicity problem with the mine water was limited to the first longwall district. Mining in this <br />district was completed in eady 1993. The district has since then been sealed underground. There <br />was no pumping of accumulated water in this district during this water year. The second longwall <br />mining district water is pumped through SDH-3 and SDH-5. No toxicity was indicated during this <br />water year. <br />2.3 Red Wash Alluvial Monltoring Program <br />Portions of Red Wash have experienced subsidence due to longwall mining at the Deserado Mine. <br />As required by CMLRD, Western Fuels initiated a detailed hydrology monitoring program in Red <br />Wash above the first longwall panel to be mined. The monitoring program consists of nine (9) holes <br />drilled in the Red Wash alluvium across the predicted zone of subsidence from longwall panel 1 <br />(LW-1). Water levels in the holes were monitored before, during and after active subsidence took <br />place. The purpose of the monitoring program was to determine if surface flow in Red Wash was <br />being lost to bedrock as the result of subsidence. <br />The monitoring data, analysis and conclusions reached were submitted to CMLRD in an Interim <br />Report, November 1987, and in the Third Annual Hydrology Report, January 1988. The purpose of <br />the monitoring program was met in that it was determined that surface flow in Red Wash was not <br />lost to bedrock as a result of subsidence. The major conclusions of the study were: <br />• Recharge of the basal alluvium is from the upper sandstone facies (bedrock) <br />and not from infiltration of surface runoff. <br />• Subsidence cracks in Red Wash as the result of longwall mining are quickly <br />filled with clay and silt preventing loss of surface water flow to bedrock. <br />Although the purpose of the monitoring program has been met, Western Fuels is continuing to <br />monitor the Red Wash alluvial holes. The monitoring results are reported in Appendix F and <br />hydrographs far each monitoring hole are presented in Appendix G. <br />Longwall mining of panel 2 (LW-2) passed under Red Wash in September 1988. The surface <br />elevation has subsided approximately 3.7 and 4.1 feet at RW-7 and RW-9 respectively. Events in <br />Red Wash over LW-2 were expected to occur in the same fashion as those seen over LW-1. The <br />subsidence trough was developed and any subsequent flow in Red Wash was expected to form a <br />16 <br /> <br />