2001-02-21_REVISION - M1977493 ‎(4)‎

• Permit No: M1977493
• IBM Index Class Name: REVISION
• Doc Date: 2/21/2001
• Doc Name: Appl. and Exhibits
• From: Climax Molyb
• To: DMG
• Type & Sequence: AM4
• Email Name: ACS
• Media Type: D
• Archive: No

• 0
• Climax was placed in a ready state, care and maintenance condition as a swing producer capable
of production from the open pit as the market dictated. Since that time, Climax has operated at
market dictates. Other than a brief period of limited production in early 1995 in response to a
short-lived market upswing,recent activities at Climax have involved upgrading and maintenance
of the complex water control and treatment system and extensive closure and reclamation of
facilities no longer foreseen as required for production. As stated, Climax is considered a swing
producer within the industry and intends to maintain that status. Presently, the operation
employs approximately 25 people at the site.
1.1 Site Facilities
Major components and facilities at Climax include the Storke complex and water return systems,
open pit, mine and mill complex, E-dump, McNulty waste rock dump, Ten Mile tailings
impoundment, No. 3 dam (Ten Mile impoundment), pond shop area, Mayflower tailings
impoundment, water treatment facility area, Robinson tailings impoundment, Robinson Lake,
Eagle Valley borrow areas, Clinton gulch, haulage and access roads, and the extensive water
routing,pipeline, and flood control system. Conversion of the oxide tailing impoundment area,
located just below the Robinson Lake, to a fresh (non-process) water storage reservoir for Vail
• Associates ski area was initiated 1993 and completed in 1998. This site has been renamed 'Eagle
Park Reservoir". These aforelisted facilities are subject to the financial warranty presently held
by DMG. Map 1 identifies these facilities and is the reference base map for this petition.
1.2 Mayflower Tailings Impoundment and Borrow Area History
Located directly downstream of the Ten Mile tailings impoundment and No. 3 dam, construction
of the Mayflower tailings impoundment and No.5 dam was completed in the late 1970s. The
Mayflower tailings impoundment was designed and constructed at a time when Climax was in
full production and the molybdenum market was stable and showing signs of significant increase.
The Robinson tailings impoundment was near design capacity, and the Ten Mile impoundment
was forecast at capacity within a decade. Mayflower was engineered as a modern tailings facility
for that period and designed with the ability to raise the dam incrementally with on-going mine
and mill production. However, as discussed at the beginning of this section, the world market for
molybdenum collapsed in the early-mid 1980s causing Climax to cease production in 1987.
During this period, Climax engineers determined that the optimal approach to managing the
operation and, particularly, water balance and treatment, would be to maintain the Ten Mile
tailings impoundment as operational for tailings deposition while incorporating the Mayflower
impoundment into the water treatment system as a large end-line settling basin.
. Climax was cited by DMG for blowing tailings dust during an inspection in 1986. The result of
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