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Part I Page No. 3 Permit No.: CO-0046348 TERMS AND CONDITIONS PARTI Beginning no earlier than the effective date of this permit and lasting through October 31, 2007, the pemtittee is authorized to operate under the terms and conditions of this pemvt. Discharges are authorized only from the following specific outfalls, as shown on Figure 4 of the Permit: Outfall OOlA, which is the discharge to Arequa Gulch from the sedimentation pond located downstrean of the Valley Leach Facility (VLF) at monitoring point AG 1.5, which is located approximately 350 feet downstream of the sedimentation pond crest, and Outfall OOSB, for qualifying precipitation related discharges from the VaIIey Leach Facility at a point below Outfa11001A. In accordance with the Water Quality Control Conunission Regulations for Effluent Limitations (5 CCR 1002-62) and the Colorado Dischazge Permit System Regulations (5 C.C.R. 1002-61), the permitted dischazge shall not contain effluent parameter concentrations, which exceed the limitations specified below, or exceed the specified flow limitation. a. "Nn T)iccharge" T.imitation for the VT.F Except as allowed under the exemptions described in the sections below, there shall be no dischazge from the VLF, pursuant to federal effluent guideline regulations at 40 CFR, Part 440.104. This ]imitation does not apply to any flows from the ground water drainage system underlying the VLF. b. Anmtal precipitation Fxemntinn Frnm "No T)iccharoe" T imitation - Outfall OOSR Ptrsuant to 40 CFR Part 440.104, in the event that the annual precipitation (measured as a 365-day, moving average) falling on the VLF and the drainage area contributing surface mnoff to the VLF exceeds the annual evaporation (also measured as a 365-day moving average), a volume of water equal to the difference between annual precipitation falling on the VLF and the drainage area contributing surface runoff to the facility and the 365-day moving average evaporation may be discharged subject to the limitations set forth in Table VI-2 for Outfall OOSB. Verbal notification shall be given within 24 hours, and written notification shall be submitted to the Division within 5 days o£ any discharge from the VLF that would qualify for this exemption. e, Ctnrm Fxemntion Frnm Federal Ffflnent T imitations - (~ntfall OOSR Pursuant to 40 CFR, Part 440.131, if, as a result of precipitation, the Valley Leach Facility has a dischazge, which violates limitations of 40 CFR Part 440 or water quality standazd based limits, the discharge may qualify for an exemption from such limitations if the following conditions are met: i) The facility is designed, constructed and maintained to contain the maximum volume of process water stored and contained by the facility during normal operating conditions without an increase in volume from precipitation and the maximum volume of water resulting from a 10-yeaz, 24-hour precipitation event. In computing the maximum volume of water, which would result from a 10-yeaz, 24-hour precipitation event, the facility must include the volume, which would result from all areas contributing runoff to the Valley beach Facility (i.e., all runoff not diverted from the active ore leaching area). For the purposes of this pemtit, the 10-yeaz 24-hour rainfall depth has been determined to be 2.4 inches. ii) The pettnittee takes all reasonable steps to minimize the dischazge. iii) All notification requirements of the pemtit aze complied with, including those listed below. Verbal notification shall be given by CC&V immediately to the Division upon beconung awaze of an imminent dischazge and no later thazt 24 hours after the start of any discharge from the Valley Leach Facility that may qualify for the exemption described herein. A report must be submitted within 5 days of the said dischazge, documenting that the facility was maintained to contain the previously specified volumes. The pemuttee must also submit documentation of the storm event, including results gathered from the precipitation gauge station in close proximity to the VLF (or the pemrittee's own gauge), the volume of mnoff produced and the steps taken to maintain treatment and minimize the amount of overflow.