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SECTION 2.05.6(3)(b)(v) <br />HYDROLOGIC RECLAMATION PLAN <br />INTRODUCTION <br />The hydrologic reclamation plan for NHN permit area is presented in two parts. The first part <br />focuses on specific practices which are conducted to minimize the impact of mining on the <br />hydrologic balance within and adjacent to the permit boundary. The second part addresses those <br />impacts that may occur regardless of these practices. The emphasis of the second part is on the <br />monitoring of the extent and magnitude of mining impacts. Where possible, reference has been <br />made to those sections which contain details regarding certain practices. <br />PRACTICES EMPLOYED TO MINIMIZE THE IMPACTS OF MINING ON THE <br />HYDROLOGIC SYSTEM <br />Ground Water Oualily The mining practices that involve replacement of spoil material into <br />mine pits are detailed in Section 2.05.4(2)(c), Backfilling and Grading. Topsoil and overburden <br />handling plans are detailed in Section 2.05.4(2)(d), Topsoil (Redistribution). An extensive <br />analysis of the spoil water quality and quantity was done for the bond release of New Horizon #1 <br />area in the year 2000. Based on years of monitor hole data and spoil spring data, it was shown <br />that although pyrite oxidation would slightly increase the Total Dissolved Solids (TDS) of the <br />water emanating from the spoil, the levels of increased TDS and pH were low enough that when <br />mixed with Tuttle Draw and the San Miguel River, the increases were negligible. It was found <br />that the increases were expected for a considerably long period of time, probably from 400 to <br />1500 years. After this amount of time, the pyrite will be fully oxidized and the ground water <br />quality will be back to background levels, which is still high in TDS. Because of the findings on <br />negligible impacts to water quality, no special handling of materials is anticipated for mining <br />operations conducted. The method of mining by removing the weathered, oxidized, free dig <br />material separately from the unweathered bedrock and then covering the unweathered <br />overburden with the weathered oxidized free dig material is done routinely to aid the mining <br />operation and is not considered "special handling ". The practices of dilution of any unsuitable <br />overburden and burial have worked to date at the adjacent New Horizon Mine. Selective <br />handling would only be used if some unforeseen overburden zone is much worse than any <br />encountered to date. In this case, it would be buried deeper in the backfill spoil than what would <br />occur in the normal overburden mixing. <br />Each exploration hole, other drill or borehole, well, or other exposed underground opening <br />except those used solely for surface blasting will be plugged or sealed to prevent acid or toxic <br />drainage from entering the ground water, minimize disturbance to the prevailing hydrologic <br />balance, and ensure safety. Any holes, wells or other exposed underground opening that will be <br />Section 2.05.6(3)(b)(v) Page 1 April 2011 <br />