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The effects on the side canyon drainages should be similar to dre Purgatoirc alluvium. Based on general <br />• geologic mapping, the alluvial area of each canyon was multiplied by the permeability. The water lost to <br />seepage in Apache Canyon has been estimated at 0.3 gpm. This represents less than one percent of the <br />calculated runoff for this canyon system. <br />The Purgatoirc River monitoring sites, PRS-I 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 vut of service for Ore entire year. <br />Pond 8 discharged after precipitation events in July and August. No discharges from any of the other <br />ponds at the property were recorded in 2004, due to limited operational activities and average climate <br />conditions. Pond 8 operated as "pass through" faoility in 2004. An cxccdcnce of the alternative limitation <br />for sediment (settleable solids) was reported for [he pond 8 outfall. As a mitigative measure, water levels <br />in the pond wcrc reduced by pumping water to pond 6 to provide addilioual retention time for fidure <br />precipitation events. Additionally, the active surface of the refuse disposal area contributing the majority <br />of the flow to pond 8 was regraded to reduce erosion due to the intensity of flow from the surface area. <br />The outlet to pond 7 was maintained in the closed position. The operational plan calls fora preliminary <br />water sample to be collected and tested for settleable solids prior to initiating any discharge from the <br />pond. <br />Water levels for alluvial wells (PAW -series) wcrc within historic ranges for water levels at individual <br />sites. The depth to water was lower throughout the year, responding directly to reduced water flows in <br />• the river. <br />3.1.3 Groundwater <br />As might be anticipated from no noticeable impact from dewatcring activities conducted in the 19811'x. <br />there has been no noticeable impact on groundwater hydrology from d+e gradual flooding of the New Elk <br />Mine. The apparent low vertical transmissivity and integrity of the surrounding rocks might inhibit any <br />effect of free water on the recharge of the overburden."I7re depths to which recovery might be taking <br />place aze probably too far removed from the ground surface to manifest any impacts at the surface (seeps <br />and springs) at this time. <br />3.1.4 Piezometers <br />Refuse Disposal Area piezometer readings arc included in this report (Table B-IOI. TH-201, on the first <br />bench, and TH-202 and TH-203 on the second and third benches had minimal water throughout the year. <br />Embankment stability, the primary purpose of the piezomcters, is discussed within [he quarterly waste <br />pile certifications. <br />3.2 WATER QUALITY <br />3.2.1 Springs and Seeps <br />The 2004 spring and seep survey occurred in August. No significant flows wcrc observed at any of the <br />• four monitoring sites; minor seepage was noted at Apache Canyon 12 and 14, and Parras Canyon Spring <br />19. There is no evidence that mining activities have affected the water quality of springs or sccps, nor are <br />such changes anticipated. Additional discussion of springs and sccps is contained in Appendix C. <br />15 <br />