Laserfiche WebLink
October 2012 Page 3 -2 <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. <br />Based 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 systems. <br />The Purgatoire River monitoring sites, PRS -1 and PRS -4, had flow throughout the year <br />similar to those encountered in previous years. <br />The sewage treatment plant operated into September 2011. The treated water flows to a <br />non - discharging pond. The STP has been removed from service and the effluent transported to <br />the City of Trinidad water treatment plant for treatment. A larger plant is being permitted with <br />CDPHE and will be designed to meet PEL standards. It is expected to be in service by mid -2013. <br />Until then effluent will be treated by the City of Trinidad Plant. There was not sediment pond <br />discharge during the year. <br />Water levels for alluvial wells (PAW- series) were within historic ranges for water levels <br />at each of the monitoring sites. <br />3.1.3 Groundwater <br />As might be anticipated from no noticeable impact from dewatering activities conducted <br />in the 1980s, there has been no noticeable impact on groundwater hydrology from the gradual <br />flooding of the New Elk Mine. The apparent low vertical transmissivity and integrity of the <br />surrounding rocks might inhibit any effect of free water on the recharge of the overburden. The <br />depths to which recovery might be taking place are probably too far removed from the ground <br />surface to manifest any impacts at the surface (seeps and springs) at this time. <br />3.1.4 Piezometers <br />Refuse Disposal Area piezometer readings are included in this report (Table B -10), <br />TH -201, on the first bench, and Th -202 and TH -203 on the second and third benches had <br />minimal water throughout the year. Embankment stability, the primary purpose of the <br />piezometers, is discussed within the quarterly waste pile certifications. <br />3.2 Water Quality <br />3.2.1 Springs and Seeps <br />There is no evidence that mining activities have affected the water quality of springs or <br />seeps, nor are such changes anticipated. Springs and seeps were not monitored during the year. <br />3.2.2 Surface Water (Streams and Rivers, and Ponds and Direct Discharges) <br />Results of water monitoring by the USGS indicate a change in water quality between <br />Stonewall, a location above the New Elk Mine, and Madrid, a location below the Golden Eagle <br />