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3.1 WATER QUANTITY <br />3.1.1 Springs and Seeps. <br />• Assessment of springs and seeps (Appendix C) indicate that mine operations at the New Elk <br />Mine have not affected current uses of springs and seeps. Theoretically, these resources in the <br />vicinity of mining activity, especially over those areas of longwall mining, could be affected. <br />There is some potential for the loss of spring and seep flows into the underground mine <br />workings by fracture systems developed through land subsidence. No impacts to flow have <br />been documented to date. The monitoring requirement for these sites was terminated in 1999 <br />with the liability release for areas of underground mining <br />3.1.2 Purgatoire River System [Surface (Streams and Rivers), Ponds and Direct <br />Discharges, and Alluvial Groundwater] <br />Use of the river in the area of the mine is limited to livestock watering, habitat for fish and <br />terrestrial wildlife, flood irrigation on bottom land terraces, and water supply for the New Elk <br />Mine preparation plant. Because of closure of the Golden Eagle Mine and no processing of <br />coal at the New Elk prep plant, there was no consumptive water use at the mine. The average <br />annual runoff of the Purgatoire River at Madrid (USGS site 07124200) between 1972 and 1995 <br />is 51,740 ac ft. <br />There is a slight potential that flows in the Purgatoire River might be diminished by recharge <br />seepage into the mine along the river. Vertical permeability of the overburden on the mine <br />property has been estimated at 0.00021 feet per day (mine permit document). When this low <br />permeability is multiplied by the horizontal surface area of saturated alluvium in the area of the <br />• mine, downward flow of water is estimated at 2.3 gpm. With the flow measured in the <br />Purgatoire River, this small water loss would not be detectable. Similarly, any loss in alluvial <br />groundwater would likely be undetected. Flows of the river replenish any alluvial groundwater <br />lost to seepage. However, as the theoretical permeability is very low, no loss of river or alluvial <br />water has been detected. <br />The effects on the side canyon drainages should be similar to the Purgatoire alluvium. Based <br />on general geologic mapping, the alluvial area of each canyon was multiplied by the <br />permeability. The water lost to seepage in Apache Canyon has been estimated at 0.3 gpm. This <br />represents less than one percent of the calculated runoff for this canyon system. <br />The Purgatoire River monitoring sites, PRS-1 and PRS-4, had flow throughout the year similar <br />to those encountered in previous years. <br />The water supply system and the sewage treatment plant (NE-033) were out of service for the <br />entire year. <br />No discharge from any of the ponds at the property was recorded in 2007, due to limited <br />operational activities and average climate conditions. Pond 8 operated as a "pass through" <br />facility thoughout 2007. The outlet to pond 7 was maintained in the closed position. The <br />operational plan calls for a preliminary water sample to be collected and tested for settleable <br />solids prior to initiating any discharge from the pond. <br />• Water levels for alluvial wells (PAW -series) were within historic ranges for water levels at <br />individual sites. <br />14