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3.1 WATER QUANTITY <br />3.1.1 Springs and Seeps. <br />Assessment of springs and seeps indicate that mine operations at the New Elk Mine have not <br />affected current uses of springs and seeps. Theoretically, these resources in the vicinity of <br />mining activity, especially over those areas of longwall mining, could be affected. There is some <br />potential for the loss of spring and seep flows into the underground mine workings by fracture <br />systems developed through land subsidence. No impacts to flow have been documented to date. <br />The monitoring requirement for these sites was terminated in 1999 with the liability release for <br />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 coal <br />at the New Elk prep plant, there was no consumptive water use at the mine. The average annual <br />runoff of the Purgatoire River at Madrid (USGS site 07124200) between 1972 and 1995 is <br />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 Purgatoire <br />River, this small water loss would not be detectable. Similarly, any loss in alluvial groundwater <br />would likely be undetected. Flows of the river replenish any alluvial groundwater lost to seepage. <br />However, as the theoretical permeability is very low, no loss of river or alluvial water has been <br />detected. <br />The effects on the side canyon drainages should be similar to the Purgatoire alluvium. Based on <br />general geologic mapping, the alluvial area of each canyon was multiplied by the permeability. <br />The water lost to seepage in Apache Canyon has been estimated at 0.3 gpm. This represents less <br />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 to <br />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 throughout 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 suspended <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 each <br />of the monitoring sites. <br />14