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3} Hole 29-4 4) Engleville Mine Discharge A revision was approved on March 27, 1995 to discontinue monitoring of ail sources due to the established data, which showed little fluctuation in the well conditions and water quality. Also, the mine had ceased operations and had been reclaimed, so that no new effects were possible. Surface Water The quality of the impounded water in the sediment pond is acceptable, as shown in the analysis of discharge submitted for the NPDES permit and the annual reports submitted to the Division. This water represents the runoff from virtually the entire disturbed site. The pond was originally designed for a larger disturbed area than that actually disturbed, therefore, it has extra capacity to detain sediment. Also, the original pond design assumed that the disturbed area would have a high CN (disturbed). The site has re-vegetated well, thus further reducing the sediment that enters the pond. Due to these factors, it is clear that the pond will meet all applicable State and Federal water quality standards. The sediment pond was approved in the 1995 Renewal to remain as part of the post-mining use of rangeland. 6.Other Hydrolo¢ical Impacts No other impacts to the surround area's hydrology have been observed at the site. 7. Vegetation Analyses Vegetation analyses were preformed in the summers of 2002, 2003, and 2004 under the state's SOAP program. The 2002 analysis showed insufficient vegetative growth, however this is attributed to the severe drought experienced during that period. Studies performed in 2003 and 2004 showed cover of greater that premine conditions. Copies of the vegetation studies are included in Appendix B. 8. Subsidence Features Active mining in 1993 did encounter narrow underground workings from the late 1800's Engleville Mine. All exposed workings were backfilied using heavy equipment, and the land was returned to approximate original contour. The approximate area where workings were uncovered was 1.5-2.5 acres. Since backfilling in 1993, only one small subsidence hole, 1-2 feet in diameter, was found and refilled. Given the passing of 12 years since backfilling, there is no reason to believe subsidence will be a future problem. In fact, the chance of subsidence has been greatly lessened in area the surface mine encountered underground workings.