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Mr. John Walters - page 2 <br />• coal seems to be more fractured within several hundred feet from <br />the fault. The east fault was approached at 7 locations within <br />the mine. This fault, dipping approximately 60 - 70° to the <br />northwest, has typically 4 to 12 inches of gouge and does not <br />contain highly permeable materials. The Cameo coal seam is <br />visibly arching within the mined graben. <br />Water Inflow Into the Mine <br />The first water inflow into the mine occured when the east <br />mains reached the east fault. However, the inflow was limited <br />and lasted only several days. Two exploration boreholes were <br />drilled from the east face of the 1st and 4th mains through the <br />fault toward the east at an updip angle of 45 to 36 degrees. <br />Both boreholes penetrated the strata between the displaced parts <br />of the Cameo coal seam and water was dripping from both boreholes <br />for several months. At the time of the site visit, both <br />boreholes were dry. A limited water inflow from the fault into <br />the mine was observed at two other locations (5th, 6th and 8th, <br />9th crosscuts) where the fault was contacted by the mine <br />crosscuts. Located at these locations are two of the three <br />existing mine sumps. An increase in water inflow into the mine <br />was observed in June, 1982 when the mine progressed approximately <br />to the 12th crosscut. The Cameo coal seam floor in this area is <br />at an elevation of approximately 5,580 feet. With the mine <br />• advancing toward the northeast between June and December, 1982 <br />the water seepage into the mine was gradually increasing. <br />According to Mr. Walters, water was seeping through the floor <br />between the mine face and about 200 yards behind the face. Small <br />gullies eroded by water flowing toward the mine face are still <br />visible in the mine. At the time of the mine visit no visible <br />water seepage from the floor was observed, however, the mine <br />floor in the last several hundred feet from the face was moist. <br />There is no evidence of water inflow into the mine from the <br />roof. No dripping or stains around the roof bolts were observed. <br />Several boreholes drilled upward from the crosscuts 7 to 40 feet <br />above the mine roof experienced only temporary dripping after <br />completion. The only exception where water was found dripping <br />from the roof was at the 1-14 crosscut. At this location the <br />water dripping from the roof created a stalagmite type of icicle <br />about 8 inches in length. <br />Due to the type of water inflow into the mine it is <br />difficult to measure the exact rate of water flowing into the <br />mine. However, from well documented water handling between <br />January, 1982 and January, 1985 it was possible to interpret the <br />general trend of water inflow into the mine. According to the <br />presented Salt Creek documentation, the mine water is stored in <br />three in-mine sumps and pumped on an as-needed basis out of the <br />mine. During the mine operation part of the mine water was used <br />for dust control, a small quantity was exported to the Munger <br />Canyon mine and the rest was pumped into the sedimentation pond <br />and discharged into McClave Creek. <br /> <br />