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J. J. Dudash - 2 - October 28, 1998 The storage volume of the West Ridge Waste Pile was estimated to be approximately 261,000 cubic yards and is near full at this time. The new East Ridge Pile will store approximate]y 310,000 cubic yards of waste material, which should take care of the mine for the next twenty yeazs depending on future production rates of the mine. The DMG has been concerned about the status of the run-of--mine stockpile. Although the stockpile is bonded for the amount of material present, a proper waste disposal area is not available for that amount of material. The new East Ridge Pile will provide adequate capacity for the run-of--mine stockpile. The East Ridge Waste Pile construction methods, topsoil handling, access, site preparation, waste disposal, maintenance and reclamation shall comply with the historically successful West Ridge Waste Pile design. Drainage routing and structures aze shown on revised Map No. 6A-1F found in Volume 6A, Maps. Surface drainage on the east side of the cover-fill stockpile is routed to existing Pond #2. Runoff from the west side of the cover-fill pile and the east side of the waste pile is routed to Pond #3 via various collection ditches. The west side of the waste pile and the West Ridge pile is drained through various collection ditches into the Waste Area Pond. The capacities of the Waste Area Pond and Ponds #1, #2, #3 and #4 were evaluated to verify the runoff from the 10 yeaz-24 hour storm event can be contained since additional ground disturbance and drainage changes are proposed. This evaluation showed additional water storage capacity was required. Therefore, the Waste Area Pond will be enlarged prior to construction of the East Ridge pile. The run-off and ditch sizing calculations are presented in Volume 8, Drainage Ditches, pages 1 through 20. The plan to enlazge the Waste Area pond is presented on Map 6A-2C. Although there has been no recorded groundwater within the East Ridge Waste Pile footprint, an underdrain has been developed to ensure the interception of any ground water present beneath the pile. Drain material must be permeable and protected by a fabric filter. The drain will be covered with natural material to protect against entrance of leachate from the waste. The drain itself will be constructed in the natural drainage located within the footprint of the East Ridge Waste Pile. The upper end of the rock drain will end at the toe of the crushing and screening level fill. The rock drain shall be terminated at the toe of the East Ridge Pile, immediately north of the access road culvert where any discharge will be routed to Pond #3. The underdrain specifications are derived from the East and West Rock Drain design prepazed by Bukavansky Assoc. Ltd. and Hydro-Triad Ltd. in 1994, presented in Volume 8, New Disposal Area, Pages 3 &4 and Figure 3. The drain layout and design is shown again on Map No. 6A-1F. The estimated reclamation bond may increase, however a credit should be given for task #22 which has been completed on the existing waste pile. The new pile will require placement of approximately 33,500 cubic yazds of cover material.