2024-04-02_REVISION - M1977493

• Permit No: M1977493
• IBM Index Class Name: Revision
• Doc Date: 4/2/2024
• Doc Name: Proposed Revision Materials
• From: Climax Molybdenum
• To: DRMS
• Type & Sequence: TR37
• Email Name: DMC
• Email Name: ACY
• Email Name: THM
• Media Type: D
• Archive: No

Permit M-1977-493—Climax Mine Technical Revision 37 (TR-37)
E-11 Site-Specific Reclamation Planning
Using the general guidelines for grading, soil placement, soil amendments, and seeding described above, specific
reclamation strategies have been outlined for several areas on the mine. This section includes reclamation plans
for the open pit, McNulty and North 40 OSFs, and the three TSFs. Figures G-03 through G-07 (Exhibit G)
illustrate the final reclamation design with respect to water management. Figures F-01 through F-07 (Exhibit F)
illustrate the final reclamation design with respect to revegetation and which seed mixes to be used on selected
areas of the mine. Figure F-02 indicates the approximate location for each stockpile used in the reclamation
process. The four stockpiles located east of State Highway 91 will be used for facilities such as the Mill, North 40
OSF, and McNulty OSF. Stockpiles located west of the highway are generally insufficient to provide full cover to
their designated areas. Most cover for these areas will originate from proposed Stockpile 30 that will contain the
reclamation cover from the future expansion areas of the Mayflower TSF, as shown in Figure F-02. A summary of
acres of reclamation cover to be placed for each facility is included in Table E-8.
Table E-8: Reclamation Cover Areas by Facility
Facility Reclamation Cover Areas (ac)
McNulty OSF 683.4
North OSF 235.4
Mayflower TSF 883.4
Tenmile TSF 625.1
Robinson TSF 456.8
Robinson Lake Area 42.6
1 Dam 126.8
3 Dam 28.9
5 Dam 60.9
Mill and Pit Area 241.1
Roads 112.8
E-11.1 Open Pit
Most of the open pit will not be revegetated due to accessibility and safety concerns (Figures F-03 and G-03,
Exhibits F and G, respectively). Thus, most of the open pit will be reclaimed to a talus community (see Exhibit J:
Vegetation Resources for community description). The final slopes will likely remain at their current configuration.
Weathering, colluvial deposition by gravity, and ice action will cause natural reshaping of the benches and
highwalls over time, but blasting may also be used to soften visual impacts. Administrative controls (fencing and
access restrictions) will be maintained to control public access.
A haul road fill area is located on the south crest of the open pit (also known as Ceresco Ridge). This road fill will
be excavated down to the pre-mining ground, hauled, and placed on the bottom of the pit. The pre-mine ground
beneath the haul road fill will be reclaimed with reclamation cover.
On the margins of the pit, where slopes are less steep, some revegetation may be possible. In these cases,
topsoil may be hauled from a nearby reclamation cover stockpile, then seeded with the appropriate seed mix.
E-11.2 McNulty and North 40 Overburden Storage Facilities
The lower portions of the McNulty and North 40 OSFs may be reclaimed concurrently with production, but final
reclamation will not be completed until the OSF is no longer required for production. Final grading of the OSFs will
be not steeper than 2H:1 V with some areas considerably less steep.
Prior to reclamation cover placement, the angle of repose inter-bench slopes will be flattened to 2H:1 V with
sideslope channels graded into the remaining benches. The sideslope channels will report to articulated concrete
Exhibit E E-12 March 2024