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TABLE 1 <br />WATER INFLOW INTO THE ORCHARD VALLEY MINE <br />1985 - 1989 <br />YEAR MINED AREA MINE INFLOW TOTAL MINE <br />(acres) IN THE INFLOW <br />' SPECIFIC (gpm) <br />AREA (gpm) <br />' 1984 660 4.0 4.0 <br />1985 142 0.9 4.9 <br />1986 130 0.8 5.7 <br />1987 108 0.7 6.4 <br />1988 234 1.4 7.8 <br />1989 141 0.9 8.7 <br />' TOTALS 1,415 8.7 8.7 <br />' Table 1 indicates that by the end of year 1989 the total <br />water inflow into the Orchard Valley mine will be approximately <br />double the existing inflow. This should be considered a worst <br />case scenario, because the inflow in the old sections of the mine <br />are not constant and tend to decrease with time. This is due to <br />the absence of significant aquifers and surface streams in the <br />mined area. (Refer to map No. 2-4, 5 Year Mine Plan of the <br />application for permit to mine). <br />2.2.2 Mine Plans After 1989 <br />No precise mining plans are available for the years <br />following 1989. The mine will be developing toward the north- <br />east and the north-west and west of the exisitng mine. Mine <br />' development after 1989 is shown on Figure 1. in the north-east <br />sector of the mine, no significant surface streams will be <br />undermined and the thickness of the majority of overburden will <br />' be over 1,000 feet. Therefore, no significant changes in the <br />mine inflow patterns and quantities are anticipated in the north- <br />eastern sector of the mine. For this reason, the method of <br />Hydrogeologic Analogy was used for the calculation of the water <br />' inflow in this part of the mine. <br />Mine inflow characteristics could change during the <br />' development of the north-western sector of the mine. In this area <br />more significant surface streams, Stevens Gulch and East Roatcap <br />Creek, will be undermined. Although maximum precaution of <br />leaving in-place buffer zones underneath the referenced streams <br />is included in the mining plans, certain increase in the mine <br />water inflow is anticipated. <br />An initial increase in water inflow could be experienced <br />while driving the West Mains underneath the two mentioned <br />drainages as shown on Figure 2. The knowledge of local geology <br />and the experience from other mines in the Somerset mining <br />4 IIPUNU-fl:U CI4VSULT IVT3 <br />