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-2 - Mine water importation is best estimated from recorded flows and related tonnages at the Orchard Valley Mine from September of 1985 through April of 1986. Calcu- lations from recorded measurements indicated approximately 2.SX by weight of im- ported water (in relation to the total raw coal tonnage) is used for face and roadway dust control. 'Ibis relates to an import water usage of 3,666,000 gallons from July of 1988 through June of 1989. From detailed coal sampling at the face and on the moisture gain from the inplace value to the train Consequently, 1,466,000 gallons of water are imported Therefore, approximately 2,200,000 gallons of water control, with a small percentage of this evaporating being expelled from [he mine. HYDROLOGIC INPACTS surface, an approximate 1% loadout point is apparent. for face coal dust control. are used for roadway dust as humidity into the air and No significant increase in mine inflow occurred relevant to undermining Panel G d wring the last year. As stated previously, small seeps were evident in the crosscut ~f20 area in a northwest oriented direction after advancement was com- pleted. Overall, Panel G was relatively drv. Inflow amounts should not increase significantly within the next year, as the area within Panel H projections indicates an approximate 1X increase in inherent moisture. Small seeps will probably be evident for short intervals after mining, but will probably be consistent with past history and dry up over the long term. Projections of small seeps in the area of lateral shears from Panel G are ex- pected in Panel Hat the orientation seen previously. Panel N will not undermine any major drainages and will be under an average deeper overburden than Panel G. Within the next year, little more than short-term natural inflows should occur in the newly mined out areas. M y increase in natural inflow will be approximately proportional to the increase in developed area. CONCLUSIONS Present mine inflow into the Orchard Valley West Mine is low. •Ihe present flow rate is slightly below 1,400,000 gallons anually. Cyprus Orchard Valley Coal Corporation anticipates that water inflow into the mine will be increasing ap- proximately proportional to the amount the D seam is developed. Cyprus Orchard Valley Co a1 Corporation plans no mine discharge during 1989 or 1990. 'Hierefore, the quality of surface water adjacent to the Orchard Valley West Mine will not be affected. Cyprus Orchard Valley Coal Corporation will continue to submit an Annual Subsi- dence and Hydrology Report, which will summarize all subsidence and hydrology data. This study is part of that annual report.