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Jtm Herron -2- March 7, 1984 5. The mayor source of mine inflows to the Roadside Mtne is through the dewatering of the Cameo coal seam. Ground water in the coal flows through cleats (internal fractures within the coal). The inflows from the coal seam appear as weeping coal faces and ribs. These weeping coal faces and ribs are located around the outermost extents of the mine which are adjacent to undisturbed coal. Pillars and ribs within the interior of the mine have been dewatered and are dry. Dewatering of ribs was observed in the mine while travelling to the active faces. The wetted area of the ribs Increased as we approached the active faces. A distinct line of wetting was observed rising from the mine floor to the roof as we approached the active areas. 6. Powderhorn Coal Company has very effectively controlled sediment loads in their mine water by ditching the water along the side of entries and by diverting flows into entries which do not receive much traffic. This reduces the exposure of the water to coal fines and rock dust, and also reduces the churning up of suspended solids Into the water by mining equipment. This means of mine water handling should extend the life of the mine sumps (reduce sedimentation) and minimize contamination of the mine waters. The water quality improvements also improves the reusability of the water within the mine. 7. The mine was discharging water at a rate of between 40 and 50 gallons per minute. Mine waters which are discharged to the surface are pumped from a sump in the northern end of the mine near the north decline fan. water 1s pumped from the sump through a borehole to a series of two sediment ponds on the surface. The outflow from the lower pond 1s metered by an in-line flow meter which records the cumulative discharge and the flow rate. /mt cc: Brian Munson Candace Thompson Joe Oliver Phil Saletta Jim Pendleton Doc. No. 9921