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I 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 Mine have not <br />affected current uses of springs and seeps. Theoretically, these resources in the vicinity of mining activity, <br />especially over those areas of longwall mining, could be affected. There is some potential for the loss of spring <br />and seep flows into the underground mine workings by fracture systems developed through land subsidence, No <br />impacts to flow have been documented to date. The monitoring requirement for these sites was terminated in <br />1999 with the liability release for areas of underground mining <br />3.t.2 Purgatoire River System (Surface {Streams and Rivers), Pouds and Direct Discharges, and <br />Alluvial Groundwater <br />Use of the river in the area of the mine is limited to livestock watering, habitat for fish and ten-estrial wildlife, <br />flood imgation on bottom land terraces, and water supply for the New Elk Mine preparation plant. Because of <br />closure of the Golden Eagle Mine and no processing of coal at the New EIk prep plant, there was no consumptive <br />water use at the mine. The average annual runoff of the Purgatoire River at Madrid (USGS site 07124200) <br />between 1972 and 1995 is 51,740 ac ft. <br />There is a slight potential that flows in the Purgatoire River might be diminished by recharge seepage into the <br />mine along the river. Vertical permeability of the overburden on the mine property has been estimated at 0.00021 <br />feet per day (mine permit document). When this low petmeability is muhiplied by the horizontal surface area of <br />saturated alluvium in the area of the mine, downward flow of water is estimated at 2.3 gpm. With the flow <br />measured in the Purgatoire River, this sma0 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 lost to seepage. <br />However, as the theoretical permeability is very low, no lass of river or alluvial water has been detected. <br />The effects on the side canyon drainages should be similar to the Purgatoire alluvium. Based on general <br />geologic mapping, the alluvial area of each canyon was multiplied by the permeability. The water lost <br />to seepage in Apache Canyon has been estimated at 0.3 gpm. This represents less than one percent of <br />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 those <br />encountered in previous years. <br />The water supply system and the sewage treatment plant (NE-033) were out of service for the entire <br />year. <br />No dischazge from any of the ponds at the properly was recorded in 2006, due to limited operational <br />activities and average climate conditions. Pond 8 operated as a "pass through" facility thoughout 2006. <br />The outlet to pond 7 was maintained in the closed position. The operational plan calls for a preliminary <br />water sample to be collected and tested for settleable solids prior to initiating any dischazge from the <br />pond. <br />Water levels for alluvial wells (PAW -series) were within historic ranges for water levels at individual <br />• sites. <br />14 <br />