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Source of Water Inflow <br />• As detailed in previous reports, the water flowing into the mine <br />seems to be a mix of water infiltrating tl~e graben along the <br />faults and water in the' coal seam. The zone of saturation of the <br />coal seam was initially estimated using the results of exploration <br />drilling. The drilling indicated that holes in tyre McClarie graben <br />were dry; specifically, holes 7-15-3 and 7-21-1. Additionally, a <br />piezometer installed downdip from the mine outside of the graben <br />has not realized water to date. Since the well is down-dip and is <br />dry. Salt Creek surmises that the water flowing into the mine is <br />from a perched aquifer in the area of the coal mine. <br />The water witYrin the perched aquifer flowing into the mine <br />probably comes from surface water- infiltration along the faults <br />east and west of tYie mine. This assumption is supported by the <br />cyclical nature of water inflow corresponding with periods of <br />precipitation. BotYi faults have ephemeral drairiaaes crossing <br />their surface trace near the mine and may receive water from the <br />drainages. The water tYren infiltrates the coal seam which has <br />become saturated over time. Since 002 North section is updip of <br />the faces in 001 North the area has already been dewatered. <br />HUNGER CANYON MINE <br />To date there has been no water encountered by this mine: <br />therefore. there has been no effect on tl~e hydrologic regime of <br />• the area. A current mine workings map is included as Figure 2 arrd <br />Table 1 documents that there has been no water imported or used at <br />the mine. <br />PRECIPITATION <br />The 1990 water year was the driest of the decade and is tYie third <br />Year in a row of below normal precipitation (See Table 3). Only <br />10.73 inches of precipitation fell during tY,e year. This quantity <br />was 55% of the average for the decade. Snow pack during the <br />winter months was minimal. Most areas had none. !n those areas <br />where snow did accumulate, it was only ankle deep. A normal <br />snowpack is usually knee deep. <br />• <br />Page - 3 10/19/90 <br />