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' mine that produce water over the long term. Most wet areas encountered during mining flow for relatively short periods (hours or days), in the form of profuse drips, and then gradually dry out as the flow stops and the ventilation air carries the moisture out of the mine. These areas are ' generally associated with stackrock in the roof. stackrock is a sandstone laminated with very thin layers of silty carbonaceous material. These laminations range in thickness from a few inches ' to a few millimeters thick. Water in the stackrock appears to be connate in origin and not from the rechargeable groundwater systems. The smallest quantity of water entering the mine is the incidental category. This category includes leakage from water lines, dust control watering in the haulage entries, and washdown ' water used in the slope and other locations. Outyoiny Water AS coal is mined, it is wet by dust control sprays on the continuous miners, the longwall shearer and at transfer points along the conveyor belt system. This water is then carried out of the mine as surface moisture on the raw coal. This added coal surface moisture ' represents a 2% increase in the raw coal moisture content. The raw croal tonnage produced during this reporting period was 1,613,812 tons. ' Water leaving the mine as ventilation humidity represents a large quantity in the water balance. The temperature of the exhaust ventilation air is almost constant, ranging from 60° in winter ' months to 63°F in summer months. The relative humidity of this air ranges from 80% in the summer to 95% in January and February. Throughout the year, except for the months of June, July and August, the ventilation air is warmed as it passes through the mine. This increases its moisture carrying capacity and the air picks up considerable quantities of moisture wherever there is water available. During the summer months the air is actually cooled, however, the difference ' in relative humidity still allows the exhaust air to carry away more moisture than is brought in with the intake air. ' Some of the water entering the mine is collected in sumps at various locations. In the past, this water was eventually pumped out of the mine through the East Intake or to process pond two (PP2). All water discharged from the mine is now discharged at SDH-2. 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, Western Fuels initiated a detailed hydrology monitoring program in Red Wash above the first longwall panel to be mined. The monitoring program consists of nine ' (9) holes drilled in the Red Wash alluvium across the predicted zone of subsidence from longwall 13