2001-01-29_INSPECTION - M1977493

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MINE ID # OR PROSPECTING ID #: M- 1977 -493 PAGE: 3 INSPECTION DATE: 9 -26 -00 INSPECTOR'S INITIALS: ACS • Commit to a limitation of 4 -foot maximum cover fill thickness over the slab. • Figure 29 provided with the SR -03 application is described as an "as- built" drawing. However, the drawing is dated 6 -30 -96 whereas the project was constructed beginning on 7 -1 -96 and ending 9- 30 -96. Please provide a certification, as described in Rule 7.3.2(2) of the Hard Rock /Metal Mining Rules, for the 7 -shaft seal, or provide an as -built report certified by the project engineer or manager. • Provide a description of any evaluations, observations, or testing that was done on the shaft collar to determine that it would be an adequate footing for the slab • Provide an evaluation of the influence or lack of influence the use of 30 foot long wide flange beams over the center of the 28 foot shaft opening may have on the stability of the cast -in -place slab as opposed to 32 foot long beams that would be employed under IMP specifications. • Test or otherwise evaluate the cast -in -place concrete slab and provide a demonstration that the specified compressive strength specification has been met. • Describe how the steel wide flange beams were treated to resist corrosion. The reclaimed portions of the Storke Yard were inspected. Extensive building demolition was completed in the Storke Yard during 1994. Inert debris disposal from the demolition project occurred in a disposal trench as approved by the DMG in consultation with the Colorado Hazardous Materials and Waste Management Division. The Disposal trench included a compacted soil liner and leachate management system that appears to be functioning in accordance with the design intent. The leachate from the disposal trench is routed to the Storke Waste Water Treatment Plant. The remaining buildings in the Storke area include the 5 -shaft head frame and the wastewater treatment plant. There are also some foundations to be reclaimed in the 7 -shaft area as discussed previously, and in the concrete batch plant location where a backhoe was pulling up concrete foundation slabs on the day of this inspection. If Climax determines that the 5 -shaft head frame should be left as a permanent feature in the reclaimed area, the permit must be modified to remove the demolition requirement for this structure in accordance with Rule 3.1.11. The higher ground in the southeast part of the Storke Yard, above the primary storm water management ditch, has been graded to between 5 and 10:1. Some small -scale ponding of water is occurring in the regraded area; this is caused by water flowing in from the wetlands above. The regraded surface was left in a roughened and undulating condition with some medium to large sized boulders scattered throughout. The topography that has been created will provide a variety of microclimates to promote plant growth and diversity, and will provide cover for wildlife. The wet areas may eventually develop high quality wetlands similar to those in the adjacent undisturbed areas. The soil and subsoil present at the surface has been directly seeded with no application of stockpiled topsoil or other growth media. Climax determined that the application of topsoil or other cover fill would not be necessary since this part of the Storke Yard was used as a borrow area; there is no mine waste or development rock in this area so the limited available stockpiled topsoil could be more effectively used for other reclamation projects at the mine. Tree and shrub tublings have been planted. The revegetation effort in this area is doing well, but does not yet meet the performance standards of Rule 3.1.10. The DMG will reduce the surety held for grading in this area as requested by Climax in the SR -03 application. Some mining debris was noted at the surface of the regraded area, primarily rebar