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:~ ANNUAL MINE INFLOW REPORT 1988 Page -2- MINING LOCATIONS AND PROJECTIONS Development of sub-main entries within the Orchard Valley West Mine (OVWM) has entailed the major mining functions since initial production started during Jan- uary, 1987. Initial development of the I West Sub-Main from the portals in a westward direction was completed in February, 1987. The South III Sub-Mains were then driven northward with completion in July, 1987. The II West Sub-Mains were then developed in an eastward direction off the South III Sub-Mains with completion of II West in April, 1988. Panel G development was started in May, 1988, in a northeastern direction off the II West Sub-Mains. Projections for the next year are limited to continued advancement of Panel G in a northward direction to the location of the projected 47' displacement fault. CWI anticipates mining in only one section for the remainder of 1988 and throughout 1989 (see mining projections map). MINE INFLOW The mine inflow study at the Orchard Valley West Mine was completed in July of 1988. Total natural mine inflow at present is at 1,566,000 gallons annually. This equates to an inflow of 2.98 gal./min. There is presently one major location of mine inflow, the existing pilot hole for the proposed ventilation shaft at X-cu[ 4f10 of the South III Sub-Mains. The pilot hole is approximately 300' deep and from drilling records most of the wa- ter inflow supply is located 70' below the surface. This water elevation indi- cates ground water flow through bedrock. Flow from the pilot hole into the mine has been occurring since completing the pilot hole on 05/28/88. This pilot hole is the major contributor to mine inflow at present. This flow is expected to continue at least until [he vent shaft construction is completed and possibly longer depending on whether grouting will be implemented into the construction phase. The remaining inflow at [he OVWM consists of seepage both from [he roof and floor but predominantly from the floor. After immediate exposure some of the water inflow exists as a measureable flow for one to four weeks while most of the inflow exists as wet strata (roof, floor, ribs, etc.). There has been a greater number of "seeps" in relation [o mined area at the Orchard Valley West Mine than what was observed at the Orchard Valley Mine. However, the OVWM still remains a relatively dry mine with respect to other mines in [he North Fork Val- ley. MINE OUTFLOW CWI has no plans for discharge of water from within the mine to the surface. No water has been pinnped to the surface from the Orchard Valley West Mine. If ex- cessive mine inflow does occur, this excess water will be pumped into the north- ern end of the South III Sub-Mains. CWI has no long-term plans of retreat min- ing this area as it lies within the Roatcap Creek buffer zone protection area. Eventually the South III Sub-Mains will be sealed at approximately 18 X-cut and therefore this area will be available for handling any excess water.