2001-01-29_INSPECTION - M1977493

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MINE ID # OR PROSPECTING ID #: M- 1977 -493 PAGE: 8 INSPECTION DATE: 9 -26 -00 INSPECTOR'S INITIALS: ACS However, the E -dump topsoiling task is dedicated to the placement of 4 inches topsoil over a 15 -acre area on top of the dump with topsoil to be derived from the McNulty stockpile. The topsoil placed on the west out slope was from opportunistic salvage at Eagle Park and did not deplete the McNulty pile. Also, topsoil has not yet been replaced on the E -dump top surface. For these reasons, the DMG will continue to hold the relatively small amount of bond dedicated to topsoil replacement on E -dump. The Robinson Tailing Pond surface area was inspected. Dam Nos. 1 and 2 that impound the Robinson tailing are not included in the SR -03 application and were not inspected. The SR -03 application, in section 3.5, states that the "permit requires that the Robinson impoundment flats be capped with rock material to a minimum depth of 6 (inches)." DMG's position on the permit requirement for rock cover on all three tailing impoundment flats at Climax is that the minimum thickness is 1 foot. Reference page E -8 from the 1989 permit amendment AM -02 that states the tailing flats will be "capped with rock from the open pit and /or rock dumps (variable depth of 1'- 3')." A six -inch minimum rock cover thickness is specified on page E -7 for interim cover on the Mayflower Pond only. This discrepancy does not appear to be an issue since the contract for the Robinson Pond rock - capping project targeted the installation of an 18 -inch thick layer. A hand held power auger was used to drill test holes in the Robinson Pond rock cap in several locations selected by the DMG during this inspection. The high density and rocky character of the capping material made penetration with the auger difficult. More than a dozen borings were attempted, with three penetrations completed into the tailing. The depth to tailing was measured at 16 inches in two of the holes and 17 inches in the third. Rock cover depths of approximately 18 inches were also observed at the edges of the rock - capped area. Based on observations made during this and previous DMG inspections, as well as the information provided in the SR -03 application and in the Climax Mine annual reclamation reports, DMG has determined that the rock capping and haul road installation requirements on Robinson Pond have been satisfied over a 448 acre area. The 219 -acre water pool area remains to be stabilized and capped, and sufficient bond money must be reserved for this purpose. The McNulty cofferdam and haul road across the Robinson tailing surface was constructed using open pit slough rock. The remainder of the rock cap and the haul road across the tailing to No. 1 -Dam were constructed using material excavated from the E -dump. The rock cap material grades from boulder size down to coarse sand. The material is rocky, essentially devoid of organic matter, and contains a percentage of pyritic sulfur making it an acidic soil based on botanic standards. Clearly revegetation of the rock capped tailing presents a significant reclamation challenge. Climax has established a biosolids program on the Robinson Tailing Pond that will improve the texture of the cap material for plant establishment and, more importantly, will provide an organic component to the material. In addition, Climax is incorporating alkaline amendments into areas that will be seeded in an effort to buffer the acidity. Climax is to be commended for these efforts to build a viable plant growth medium from the rock cap material, and is further commended for their success in minimizing dust generation through large scale capping of tailing dams and surfaces. Reclamation of the disturbed area designated as C -14 in the 1989 amendment AM -02 was inspected. This area is located to the north and east of Eagle Park Reservoir and was originally a borrow pit used during the construction of 4 -Dam. The overall slope of C -14 is approximately 3.5:1 with small sections of much steeper slope located around the rim of the regraded borrow pit and in certain small locations where bedrock