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<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 exceed 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. Asa 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 at Golden Eagle. <br />During operations, water quality in the stream/alluvial aquifer system <br />would be affected by the discharge of water from the underground workings <br />and by seepage from existing and proposed coal refuse piles. At the New <br />Elk Mine site, existing and proposed coal refuse piles and maximum mine <br />water discharge add approximately 180 mg/1 to the total dissolved solids <br />concentration during Q7-10 low flow conditions in the tAiddle Fork of the <br />Purgatoire. This would add approximately 32 mg/1 during the low flow in <br />the vicinity of the Golden Eagle tAine due to dilution by the North Fork. <br />Maximum anticipated mine water discharge at the Golden Eagle Mine would <br />add another 58 mg/1 to low flow total dissolved solids concentrations in <br />the Purgatoire. The cumulative effect of the mine discharges and the <br />New Elk refuse pile is to increase the total dissolved solids <br />concentrations by 90 mg/1 in the Purgatoire River at Golden Eagle under <br />low flow conditions. Added to baseline concentrations of approximately <br />200 mg/1, this increase would not limit the use of water for either flood <br />irrigation, livestock watering, domestic or municipal purposes downstream. <br />The proposed Ciruela Canyon refuse pile at the Golden Eagle Mine is less <br />than one-third the size of the refuse piles in the alluvial plain at New <br />Elk Mines. Seepage from these piles is anticipated to result in a <br />negligible increase in TDS values for a Middle Purgatoire Q7-10 low flow <br />less than 15 percent of that occurring in the Purgatoire River at Golden <br />Eagle. Precipitation and infiltration values should be similar for these <br />adjacent mines. Consequently the Ciruela Canyon refuse area has little <br />potential to raise TDS or SAR values in the Purgatoire River nearby. <br />Following mining, mine water would no longer be discharged to the river. <br />Only seepage from the coal refuse piles would potentially continue to <br />affect water quality in the stream-alluvial aquifer system. Continued <br />seepage from the New Elk and Golden Eagle piles would, however, not add <br />significantly to either TDS or SAR values of the Purgatoire River. <br />-2a- <br />