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not necessary to do this task since the mine passed the'WET test during for three water years (1994-1997). Besides, no mine water is discharged at this time requiring WET testing. See Appendix H of the Thirteenth Annual Hydrology Report for WQCD's letter. The toxicity problem with the mine water was limited to the first longwall district. Mining in this district was completed in early 1993. The district has since been sealed underground. There has been no pumping of accumulated water from underground during this water year. 2.3 Red Wash Alluvial Monitoring Program Portions of Red Wash have experienced subsidence due to longwall mining at the Deserado Mine. As required by CMLRD (now DMGj, BME initiated a detailed hydrology monitoring program in Red Wash above the first longwall panel to be mined. The monitoring program consisted of nine (9) holes drilled in the Red Wash alluvium across the predicted zone of subsidence from longwall panel 1 (LW-1). Water levels in the holes were monitored before, during and after active subsidence took place. The purpose of the monitoring program was to determine if surface flow in Red Wash was being lost to bedrock as the result of subsidence. The monitoring data, analysis and conclusions reached were submitted to CMLRD in an Interim Report, November 1987, and in the Third Annual Hydrology Report, January 1988. The purpose of the monitoring program was met in that it was determined that surface flow in Red Wash was not lost to bedrock as a result of subsidence. The major conclusions of the study were: • Recharge of the basal alluvium was from the upper sandstone facies (bedrock) and not from infiltration of surface runoff. • Subsidence cracks in Red Wash as the result of longwall mining were quickly filled with clay and silt preventing loss of surface water flow to bedrock. Longwall mining of panel 2 (LW-2) passed under Red Wash in September 1988. The surface elevation subsided approximately 3.7 and 4.1 feet at RW-7 and RW-9 respectively. Events in Red Wash over LW-2 were expected to occur in the same fashion as those seen over LW-1. The subsidence trough was developed and any subsequent flow in Red Wash was expected to form a pond. The pond would trap sediments carried in the flow(s) until full, at which time flow in Red Wash would likely resume flowing in a relatively narrow active channel. ' The conclusions noted above were further confirmed during 1989. On July 29, 1989 a large flow event occurred in Red Wash. The subsidence trough over LW-2 filled with water. The trough over LW-1 also filled, but to a lesser depth as it had filled with sediment in the past. Water level ll