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The Operator should describe the ACP and ANP methods used jot the static rests given in Appendix A. /f the carbonate minerals include an appreciable percent ojeirher siderite or attkerite, the ANP should be adjusted accordingly. /jtoral carbon tests tivere run, and if the rock contains carbon species other than carbonates, those should be reported. If the test methods employed titrations or other neutralization reactions that x gold include silicate buffering, the ANP values should be re-examit7ed..46sent this, the Operator should address the question itt a narrative ar in further calculations showing that, high estimated NNP values aside, the n~srem still brill be able to minimize impacts to the h}~drologic balance. 5. The geological and mineralogical presentations show that average NNP of the Cresson pit is somewhat strongly positive (acid neutralizing) while the average NNP for the proposed North Cresson, East Cresson, and the Main Cresson lateral extension are somewhat negative (acid generating). While the overall NNP of the diatreme as a whole appear to be strongly positive, for the system to contain a substantial increase in metal concentrations waste rock from the negative NNP areas would need to be amended with alkali or blended or interstratified with waste rock from the positive NNP areas to neutralize acid generation at its source, or the waste would need to be capped to minimize infiltration of surface water. Provided acid produced from the upper mining zone is neutralized at or very near its source this could minimize dissolution of metal-bearing minerals. The mine-diatreme-groundwater system may have a limited capacity to precipitate and adsorb zinc (and other potentially problem metals) during non-upset conditions. Although modeling predictions show that the Carlton dischazge is saturated with respect to hemimorphite - Zn(SizO~)(OH)t~H~O) - none has yet been observed in the system. Absent confirming mineralogy it is presumed that zinc adsorption by carbonates precipitated in the diatreme and outside the Carlton is the dominant control over dissolved zinc. It appears important to maintain zinc contributions to the groundwater at steady state levels and this may mean not increasing the Zinc load to the subsurface without increasing the volume of carbonate precipitates. The operator should demonstrate that the x~aste hartdlirrg plan will assure either acid neutralization in the Arequa Gulch and Squaw Gulch overburden storage areas, or minimize surface water infiltration to ACOSA and SGOSA, or submit an alternative plan. XIII. 6.4.8 EXHIBIT H -Wildlife Information -Adequate IX. 6.4.9 EXHIBIT I -Soil Information A. All available growth material no matter how small, has to be salvaged. The Division will allow temporary placement of these stockpiles in close proximity prior to placement in a permanent area. 7i. 6.4.10 EXHIBIT J -1'egetation Information -Adequate XI. 6.4.1] EXHIBIT K -Climate -Adequate XII. 6.4.12 EXHIBIT L -Reclamation Costs