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<br />r1 <br />U <br />• <br />water year. Therefore, water quality sampling did <br />not begin until water year 1991. The results of this <br />sampling will be included in next year's report. <br />Mine Water Monitoring <br />Mine water inflows in areas being actively mined <br />were mapped during water year 1990. Areas of <br />previous mine inflows were monitored by occasion- <br />al visits. Exhibit II shows locations of inflows and <br />estimated amounts of mine inflows. Areas of <br />standing water are also shown. <br />Average flows were estimated for the spring runoff <br />season and the low-flow time of year (Exhibit II). <br />InOows into previously mined areas along Sylvester <br />Gulch and near the main portals continued to be <br />responsive to the spring runoff season. However, <br />the duration and amount of inflow were Icss than <br />in years previous to water year 1990 because of low <br />precipitation and runoff. Areas along the Sylvester <br />Gulch Main Mine Fan entries produced measured <br />(lows ranging from 0.25 to 0.5 gpm during low Oow <br />conditions. Spring runoff flows ranged from 3 to 5 <br />gpm. The old Sylvester Gulch area (entries 14 <br />through 2l, main intakes) produced estimated <br />Oows ranging from 0 gpm during low Oow condi- <br />tions to 1 gpm during spring runoff conditions. <br />Flows in the main portal area (entries 1 through 5) <br />were similar to those of the 1989 water year. <br />Estimated flows ranged from 0 to 0.25 gpm during <br />low Oow conditions. Spring runoff conditions <br />produced Oows of 1 to 3 gpm. Entry 1 on the east <br />side of the main intake from crosscut 1 to crosscut <br />7 had standing water year-round. Flows in this area <br />were estimated at 0.0 to 0.5 gpm during low flow <br />conditions and 2 to 5 gpm during the spring <br />runoff. Entry 9 on the west side of the southwest <br />main intakes from portal entry 5 to crosscut 7 <br />produced flows estimated at 0 to 0.25 gpm during <br />low Oow conditions and 0.5 to 1.0 gpm during <br />spring runoff conditions. <br />6 <br />AcGViuu <br />New areas mined in 1990 produced minor damp <br />and wet areas with no associated measurable flows. <br />The wet areas consisted of damp and wet roofs in <br />Panels 1W1N and 2W1N and wet roofs and Moors <br />in Panel NW1S and the "B" scam development. <br />Roof fractures and nearby sandstone channel <br />margins are probably the sources of the water. <br />During 1990, samples of mine discharges were <br />taken from the MB-l and MB-2 sediment ponds. <br />They were tested for pH, electrical conductivity, <br />total suspended solids, total dissolved solids, and <br />total iron. Results of the analysts are shown on <br />Table 5. The quality oC water sampled was good <br />and posed no problem for direct discharge to a <br />stream or other surface feature. <br />The mine water balance, based on actual and <br />estimated Oows, is shown in Table 6. The quantity <br />of water discharged or pumped from the mine was <br />approximately 35 acre feet. Water unaccounted for <br />is lost through seepage and evaporation into the <br />ventilating air. Both of these losses can be large, <br />depending on conditions. <br />