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• pressure, accompanied by high flows of water and methane and <br />forced progressive withdrawal along the section. The water <br />inflow rate was estimated to be in excess of 400 gallons per <br />minute, whereas the rest of the mine was only contributing <br />37 gpm. The available pumping systems could not cope and, until <br />additional pumping capacity was installed, it was necessary to <br />allow a portion of the section to flood. <br />The additional methane liberation from the anomaly, whose <br />nature was not known at that time, was calculated to be <br />3.3 million cubic feet per day. <br />The section was progressively recovered and, on February <br />25, 1988 it was possible to examine the face of No. 1 Heading, <br />where the anomaly was found to be the start of a step-down fault <br />system. During the recovery period, the water inflow rate <br />reduced to approximately 185 gallons per minute and the methane <br />• liberation reduced to 1.8 million cubic feet per day. <br />Geologic conditions of First and Second Right sections <br />were indicating a relatively rougher ground roll and undulating <br />roof and floor than in other areas of the mine. Increasing <br />upward flows of water and gas emissions, particularity from old <br />drill holes and the exposed mine floor in both sections, were <br />observed. No indications of faulting were apparent before <br />contact. <br />A series of fault location holes (as shown on Figure 2a) <br />was undertaken to identify the magnitude, direction and extent <br />of the fractured zone. The forward progress of the companion <br />First Right Development Section has been suspended until enough <br />data has been acquired to implement measures to prevent a <br />repetition of the incident. <br /> <br />2.04-6(c) (Revised 09/01/89) <br />