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<br />undisturbed coal surrounding the mine workings. Ground water would <br />stagnate in the mine workings and react with fragmented roof, floor, <br />coal, rock dust, and other materials in the mine cavity. This ground <br />water would have a poorer quality than water currently pumped from <br />underground workings, which is similar to ground water observed in the <br />New Elk refuse pile. The total dissolved solids levels are expected to <br />equal or exceed 2600 mg/1 (Exhibit 6, Table 13 of the permit <br />application). This ground water would spread as a plume down dip. The <br />= ~- effect of having two mining operations affecting strata in hydrologic <br />communication with one another would be to decrease dilution within the <br />aquifers and increase the distance a detectable mine water plume would <br />spread. The degradation of water quality in the coal aquifers will not <br />impact ground water use in the general area, since the poor quality and <br />depth limited use originally. <br />The two operations are expected to cumulatively affect the flow in the <br />Purgatoire River stream/alluvial aquifer system. The New Elk Mine is <br />located on the Middle Fork of the Purgatoire River. This fork joins the <br />North Fork of the Purgatoire to form the Purgatoire River. The Golden <br />Eagle Mine is located adjacent to the Purgatoire River immediately <br />downstream from the New Elk ~4ine. Both operations have undermined and <br />will further undermine the stream/alluvial aquifer systems. The amount <br />of depletion of flow in the Purgatoire River alluvial aquifer has been <br />estimated to be 5 gpm for the New Elk Mine, and 2.3 gpm for the Golden <br />Eagle t4ine. The combined predicted depletion of the stream/alluvial <br />system is 7.3 gpm (0.016 cfs) which amounts to approximately 0.1% of the <br />Q7-10 low flow in the Purgatoire River (10.9 cfs). This minor loss in <br />stream flow would be offset during mining by the discharge of mine waters <br />from the underground workings. The most current average discharge is 75 <br />gpm from the IJew Elk Mine, and 55 gpm from the Golden Eagle Mine. Full <br />development at the currently inactive New Elk Mine, however, could <br />increase mine discharge to 180 gpm; full development at Golden Eagle <br />could result in a discharge approaching 500 gpm. <br />Only the Golden Eagle Mine, as a result of encountering an artesian water <br />flow in company with a fracture zone in the Second Right entries, has the <br />apparent potential to impact bedrock aquifers below the mining level. <br />Flows of water from this source initially approached 500 gpm and <br />currently exceeds 200 gpm. Depression of the potentiometric surface in <br />the underlying aquifer as a result of this continuing flow is no doubt <br />occurring. The Trinidad Sandstone would appear to be the likeliest <br />source of this water. It is a regional aquifer with potential recharge <br />areas at and above the water level maintained by the fracture zone in the <br />mine. Because the Trinidad aquifer lies some 900 feet below the level of <br />the lowest coal worked in the New Elk/Golden Eagle Mines, no wells in the <br />area are producing water from this sandstone. As a result, continued <br />production of water from the fracture zone does not reduce use made of <br />this aquifer. Water flowing from the fracture zone into the mine is <br />discharged as mine water to the Purgatoire River as Golden Eagle. <br />-27- <br />