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Technical Revision No. 49 was approved in October 1998 to remove sediment pond 3 <br />and pond 4 after a demonstration that the area had been stabilized and was not <br />producing sediment in excess of adjacent un-mined areas. <br />In June 2001, Technical Revision No. 52 (TR-52) was approved to eliminate water <br />monitoring of surface water sites since the mine no longer discharged water to the <br />surface system via sediment ponds or mine water discharge. The mine has no effect or <br />contribution that would cause any exceedance of the receiving stream standards for the <br />Middle Fork of the Purgatoire River. TR-52 also increased the monitoring frequency of <br />the sites monitoring the mine flooding to better characterize the rate and quality of the <br />ground water entering the abandoned mine workings. <br />Technical Revision No. 53 was approved in June 2002 and the operator adequately <br />demonstrated that a ground water point of compliance was not necessary for the <br />alluvial ground water of the Purgatoire River adjacent to the reclaimed mine area. In a <br />reclaimed state, the chance that the mine could impact the alluvial water quality is <br />negligible. Monitoring data supports this conclusion as demonstrated by a comparison <br />of data collected from the upstream and downstream alluvial wells PAW-5 and PAW-9, <br />respectively. <br />In July 2004 Technical Revision No. 54 reduced water sampling of the workings to an <br />annual sample and reduced measurements in deep wells to water level only. This <br />revision also terminated spring and seep monitoring requirements entirely. Monitoring <br />during the post-subsidence period indicated no impact to springs or seeps. No springs <br />or seeps exist over the Golden Eagle mine workings. <br />The applicant has successfully demonstrated through monitoring and revision to the <br />hydrologic monitoring program over the bond liability time period that mining has not <br />negatively impacted the surface or ground water system outside the permit area. All <br />remaining water monitoring not previously approved for termination is proposed to <br />cease in conjunction with this proposed decision. Through permitting actions during the <br />bond liability period the applicant has demonstrated no impact to springs, seeps, <br />surface water, alluvial water, or deep bedrock water quality. No pollution of surface or <br />ground water has occurred or is expected to occur as a result of mining and <br />reclamation. Ground water is entering the mine workings as predicted following the <br />cessation of mining and the quality of that water is similar to water discharged during <br />the operational period. Measurements in deep wells surrounding the mined area show <br />stable or recovering water levels. The mine did not directly undermine and subside the <br />alluvial valley floor of the Purgatoire River and the absence of impacts to surface and <br />alluvial ground water supports the conclusion that the function and capacity of the <br />alluvial valley floor has been protected. <br />Support of the Post Mining Land Use <br />All hydrologic and revegetation data collected indicates that the post-mining land uses <br />of rangeland and pastureland have been successfully achieved. Periodic inspection by <br />the Division has documented use of the reclaimed area by large mammals such as elk