2001-01-29_INSPECTION - M1977493

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MINE ID # OR PROSPECTING ID #: M- 1977 -493 PAGE: 7 INSPECTION DATE: 9 -26 -00 INSPECTOR'S INITIALS: ACS • Potential impediments to successful revegetation of portions of the E -dump are the lack of topsoil in certain locations as described above. Also, the potential for die back of vegetation below areas of exposed sulfidic rock due to acidic runoff. Climax is considering the installation of a limestone drain to manage the acid seep on the west side of E -dump that was described in the DMG's 8/30/99 inspection report. Climax will consult with DMG regarding corrective measures for this seep prior to their implementation. • In most locations on the topsoiled areas of the E -dump it was noted that dozer tracking occurred parallel to the slope. On steep slopes, equipment must travel in this direction for safety. However, when possible the DMG recommends that final grading of topsoil be completed on the contour to minimize the risk of rill and gully development. • It was noted that ideal grading configuration was prevented in some areas of the west slope of the E -dump due to the location of the East Tailing Delivery Line. Climax may be required to regrade certain portions of the slope to reduce slope angle and redirect runoff at the time that the tailing delivery line is removed. The south part of the E -dump west out slope is broken by two main benches. These benches serve to reduce the overall slope, shorten the flow paths for runoff on the dump, redirect runoff to the edges of the reclaimed area, and carry roads and the East Tailing Delivery Line. It was noted in the DMG's 8/30/99 inspection report that storm water management through maintenance of ditches and berms on these benches was necessary. At the time of this inspection it was observed that runoff has been spilling over south end of the bench over a wide area and has resulted substantial erosion of the slope and deposition of gravel, sand, and silt at the toe of the slope. The approved reclamation permit states that E -dump is "designed for stability, diversion of runoff, and control of drainage," (1989 amendment AM -02). The 1989 permit amendment further states that "grading will incorporate sufficient recontouring to maintain drainage control and area stability." Climax must implement measures to reroute the runoff into a controlled non - erosive flow path and to repair the damage done be the erosion and siltation on and at the toe of the slope. These measures are to be implemented no later than the year 2001 construction season. The issues mentioned above that require corrective action on the west slope of E -dump and the Highway 91 frontage reclamation area are minor in comparison to the extensive reclamation that has been completed in this 57 acre area. Climax has surpassed the permit requirements for final slope angle and topsoil placement greatly enhancing the potential for successful revegetation in this highly visible area of the mine. The correction of issues with erosion and drainage as discussed in this report and in the 8/30/99 DMG inspection report fall under the category of maintenance and are covered in a separate section of the cost estimate used to establish the bond than the primary backfilling, grading, and topsoiling costs. Climax will continue to monitor vegetation on the reclaimed portions of E -dump and the Highway 91 frontage and will take action as necessary to promote the establishment of a self sustaining plant community. Climax has requested a reduction of bond in the amount of $421,289.00 for the reclamation work that has been completed along E -dump and the Highway 91 frontage. This dollar figure is taken from the February 1999 Climax estimate for the west side E -dump grading task and the E -dump topsoiling task. The DMG concurs that the west side E -dump grading has been completed and meets or exceeds permit requirement. The amount of bond dedicated to this grading task in the cost estimates may be eliminated.