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The inflows at the Orchard Valley West Mine continue to be <br />• minimal events consisting of seepage from both the roof and floor <br />sources. Seeps continue to exhibit the characteristic pattern <br />expected when mine workings intercept perched aquifers; flows <br />dissipate and essentially cease anywhere from one to four weeks <br />after interception by mine workings. Seeps encountered during the <br />past year failed to produce even moderate flows (>3 gpm) for any <br />significant periods of time. <br />Overall, water quantities within the mine increased slightly <br />as compared to 1992. The number of seep sources and the extent of <br />the sumps mapped are indicative of the relatively higher inflows as <br />compared to 1992. The higher incidence of inflows corresponds to <br />the extended mine area developed during the year. No water was <br />discharged from the mine to the surface during the '92 - '93 <br />reporting period. Cyprus Orchard Valley again has no plans to <br />discharge water from within the mine to the surface during the '93 <br />- '94 reporting period. No water has been discharged from the <br />mine to date. The northern end of the South III Submain remains <br />available to hold excess water which may be encountered although <br />this is not anticipated based upon the patterns of inflow <br />established thus far. <br />Water Importation and Balance <br />• Approximately 1,062,000 tons of coal was produced from the <br />Orchard Valley West Mine from July 1, 1992 through June 30, 1993. <br />Production estimates for the following twelve month period call for <br />approximately 1,000,000 tons of coal to be mined. <br />Mine water importation is estimated from recorded flows and <br />related tonnages at the Orchard Valley Mine from September of 1985 <br />through April of 1986. Calculations from recorded measurements <br />indicated approximately 2.5% by weight of imported water (in <br />relation to the total raw coal tonnage) is used for face and <br />roadway dust control. This translates to an import water usage of <br />approximately 7,770,000 gallons from July, 1992 through June, 1993. <br />From historical detailed coal sampling at the face and on the <br />surface, an approximate 1$ moisture gain from the inplace value to <br />the train loadout point is apparent. Consequently, approximately <br />3,108,000 gallons of water were imported for face coal dust <br />control. Therefore, approximately 4,662,000 gallons of water were <br />used for roadway dust control with a small percentage of this <br />evaporating as humidity into the air and being expelled from the <br />mine. <br />Hydrologic Impacts <br />• A slight increase in overall natural mine inflow occurred <br />during the 1992 - 1993 mining year addressed by this report. The <br />II West Submains and Panels Y and Z were found to be slightly <br />