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Mining Activities Open Degas Well The Golden Eagle Mine installs methane degas wells in the center of each longwall panel at regular intervals. During the February 1, 1995 inspection, degas well GE-42-89, identified on the 2/11/95 methane drainage drilling program map, was noted approximately 870 feet north of the windmill well. This degas hole was open, gas was noted issuing from the well, and running water could be heard. A depth probe was sent down the well and encountered water at 192 feet. From the map, the elevation of the water level is estimated to be 7083 feet. The well is located just south of the center of the longwall panel NW-1. Mine Ventilation Shag A ventilation shaft for the Golden Eagle Mine is located 355 feet to the northwest of the windmill well. According to the mine permit, this shaft has an inside diameter of nine feet and is approximately 600 feet deep. It serves to ventilate the longwall mining that is occurring to the northeast of the shaft. The shaft is steel-cased and was sealed with a three-hole injection grout curtain prior to being bored upwards from the workings. The grout curtain is used to seal fractures in rock surrounding the borehole shaft and to minimise mine inflows. The borehole and surrounding mine workings were initially reported to be taking in an estimated rate of up to 20 gallons per minute (gpm), but measurements taken by mine personnel with a flume in January 1995 (and as reported in the annual hydrology report) show that the current inflow is 0.2 gpm. The source of the inflow into the ventilation shaft is not known, but the shaft's close proximity to the windmill well would create a cone of depression that would likely extend to the well and thereby effect the water level in the windmill well. This cone of depression could decrease the saturated thickness of the aquifer and that could thereby result in a reduction in the well's yield. The 1st I.eR Longwall Panel (NW-1) The Golden Eagle Mine is mining the azea to the north and northeast of the windmill well using longwall techniques. As measured from the 1/24/94 subsidence monitoring map, the panels aze 600 feet wide and the development mains aze about 130 feet wide in the far west end of the mining area. The development mains, also called chain pillazs, aze located on either side of the longwall panels and are designed not to subside, as they aze needed to provide ventilation and access to the gob areas of the subsided mine workings. As indicated on the mine progress map, the panels run along the strike of the coal (North 25 degrees West). The south edge of the first left longwall panel (panel #1) is 530 feet from the windmill well according to the USGS quadrangle and the subsidence monitoring plan map. The location of the windmill well was transferred from the USGS quadrangle map onto the 3