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• TAB 16 <br />PROTECTION OF THE HYDROLOGIC BALANCE <br />Surface mining activities conducted at the Nucla Mine mining area, that are outlined in this revised <br />Permit Application Package (PAP), were planned to minimize impacts on the hydrologic balance. <br />Reclamation and monitoring plans and data reporting have been developed to be consistent with the <br />significant findings of the Probable Hydrologic Consequences analysis presented in Tab 17. The <br />following discussion addresses reclamation and monitoring plans, and data reporting in the context <br />of how they relate to ground and surface water protection and monitoring. Reference to those Tabs <br />which contain details regarding reclamation plans and practices have been incorporated. Finally, <br />discussions on stream buffer zones, alluvial valley floors, and water rights are also included. <br />The discussion for ground water protection has been divided into three parts: 1) ground water <br />qualify; 2) ground water quantity; and 3) ground water monitoring. <br />• Ground Water Quality. Mining practices that involve replacement of spoil material into mine pits are <br />detailed in Tab 20, Backfilling and Grading. Topsoil and overburden handling procedures are <br />detailed in Tab 21, Minesoil Reconstruction. These handling procedures were developed after <br />reviewing the physical and chemical properties of the overburden, coal, and interburden in both <br />mining areas (see Tab 6, Geology, and the section entitled Impacts of Spoil Water Quality on <br />Ground and Surface Water Quality in Tab 17, Probable Hydrologic Consequences). In Mining Area <br />1 (SW Pit), class 4 material as defined in Tab 21 (p. 21-2) has limitations for ground water quality, <br />including acidity which requires special handling to keep it elevated 10 feet above the SW pit base. <br />Naturally occurring waters in the surrounding undisturbed ground water system exhibit a high degree <br />of mineralization (see Tab 7, Hydrologic Description). Well yields from these units are low, and most <br />recharge to the local undisturbed ground water system is from both the Lower Second Park and the <br />west lateral irrigation ditches and associated laterals via seepage. This localized, artificial source <br />of ground water recharge will augment slower, natural recharge contributions during the spoil <br />resaturation process. As spoil resaturation progresses, the quality of ground water in the spoil will <br />likely approach the water quality of surrounding units. <br />Mixing and the overall high degree of neutralization potential of the spoil material will minimize <br />changes in ground water quality. Based on physical and chemical analyses performed on core <br />• <br />16-1 <br />