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D) The results of all monitoring will be submitted to the regulatory <br />authority within 30 days of data collection and analysis. <br />E) Due to the current temporary cessation of operations at the Munger <br />Canyon Mine, items A, B, and C listed above are modified as follows: <br />Quarterly flow measurem n n^l--y-at-surface water <br />m i e SW-3. Ground water levels will be taken at <br />moni~to~i~ng-s-ite GTi~6. Water quality samples shall be taken twice a <br />year (once during spring snowmelt and once during a storm event). <br />Surface water samples must be chemically analyzed for the parameters <br />listed below. <br />pH Magnesium (Mg+2) <br />Specific Conductance Chloride (Cl-) <br />Temperature (field) Carbonate (C03) <br />Bicarbonate (HC03) Sulfate (SOq) <br />Calcium (Ca+2) Iron (Fe) <br />Ground water samples must be analyzed for pH, conductivity and static <br />water level. This modification is in effect only for such period of <br />time that the operation is under a Division approved temporary <br />cessation of operations and no additional disturbances are created. <br />Sediment and Runoff Control <br />Information dealing with sediment and runoff control is presented in <br />Sections 2.2.7, 2.3.1, 2.3.4, 2.3.5, of Volume I, Appendix M of Volume V, <br />and Sections 2.3.5, 2.3.6, 2.3.7, 2.3.8 and Appendix As of Volume VI of <br />the permit application. This information has been reviewed by the <br />Division for compliance with the rules and Regulations and the resulting <br />analysis is presented below. <br />Mine Bench Sediment Pond <br />The proposed pond at the mine bench is designed to hold a volume of <br />runoff and sediment of 0.45 acre-feet. This capacity allows for the <br />storage of runoff resulting from the 10-year, 24-hour storm event (0.24 <br />acre-feet), as well as storage of the sediment produced from the <br />disturbance over a two-year period (0.21 acre-feet). The Division <br />requires that a sediment clean-out marker be installed in the pond to <br />indicate the level at which sufficient storage will remain for both <br />runoff and sediment generated by the 10-year, 24-hour storm event. <br />The collector ditch into the pond will be stable under the flow from the <br />10-year, 24-hour storm event. The emergency spillway is designed to <br />convey flow from the 25-year, 24-hour event without eroding. The design <br />of the pond is presented in the amended application includes provisions <br />for a dewatering device to dewater the pond down to the maximum sediment <br />storage level. <br />Currently there is an alternate sediment control structure at the mine <br />portal area. This sediment trap is adequately sized to control a <br />10-year, 24-hour storm event. Calculatins for this trap are located in <br />Appendix M (viii). The volume of the sediment trap is approximately <br />0.10 acre-feet. The Division approved the design of this sediment trap <br />_22_ <br />