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1992 ANNUAL MINE INFLOW REPORT <br />• <br />Introduction <br />In compliance with Stipulation No.29, Permit No. C-81-038, <br />Cyprus Orchard Valley Coal Company submits the following Annual <br />Mine Inflow Report for the period of July 1, 1991 through June 30, <br />1992. <br />Mining Locations and Projections <br />Pillar retreat mining of Panel A was underway in July, 1991 <br />and was completed in through December, 1991. Extension of the II <br />West submains had progressed to crosscut 1 by July 1, 1991, and <br />continued to crosscut 27 by June 30, 1992. Panel A+ development <br />initiated in January 1992 and was completed by the end of February. <br />Retreat mining of Panel A+ was completed by mid-March. Panel B <br />development was initiated in December 1991 with four crosscuts <br />developed by January 1, 1992. Development continued in March and <br />was completed by mid-April. Retreat mining, including limited <br />floor extraction within the buffer zone over Stevens Gulch and full <br />pillar extraction outside of the buffer zone, continued through <br />June 30, 1992. <br />Mining projections for the period of July, 1992 through June <br />• 1993 include the completion of retreat mining in Panel B, and <br />advance and retreat mining in Panel C. Further development of the <br />II West submains to the west of East Roatcap Creek will continue as <br />well. <br />Mine Inflow <br />The mine inflow study at the Orchard Valley West Mine was <br />completed during June, 1992. Advance development of the II West <br />submains and retreat mining of Panel B was underway during this <br />time. No measurable inflows were noted during the mine inflow <br />inspection. Four locations exhibited minor seepage from both roof <br />and floor sources, while six locations were mapped as having <br />accumulated water in sumps. One additional location was mapped <br />this year as exhibiting minor flow associated with a fault within <br />the mine and one wet area was noted to be caused by a water line <br />leak. No measurable flows were occurring at any site during the <br />monitoring tour. <br />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 />