1989-10-10_REVISION - M1988112 ‎(12)‎

• Permit No: M1988112
• IBM Index Class Name: Revision
• Doc Date: 10/10/1989
• Doc Name: GENERAL OPERATION INFORMATION
• Type & Sequence: AM1
• Media Type: D
• Archive: No

D.6.5.4.1 Main Embankment
• The main embankment has been designed as a zoned
earthfill which will be constructed in three stages.
During Phase 1 of the operations, the embankment will
be raised to an elevation of 8,590 feet. Out slopes will- be
3H:1V on the downgradient side and 2.5H:1V on the upgradient
side. The downgradient side has been designed at 3H:1V to allow
concurrent reclamation and will be revegetated upon completion
of construction as discussed in Exhibit E. The Phase 1
embankment will have a crest length of 1,450 feet. A 30 foot
wide road will be constructed on the crest for tailings
distribution lines and an access road. In addiition to the
access roads, a bench will be constructed at an elevation of
8,550 feet on the upgradient side of the Phase l embankment.
the bench will be used for initial tailings distribution.
During Phase 2 of operations two additional raises will
• be constructed on the upgradient side of the main embankment.
The raises will occur when the tailings elevations reach 8,582
feet and 8,600 feet. Construction of the raises will occur to
provide that sufficient freeboard is available within the
disposal area to contain stormwater inflows resulting from the
probable maximum rainfall (PMF). Raises will be oaf an upstream
construction type and will be placed on dewatered, consolidated
tailings. The results of the deposition modelling and
desiccation analyses indicate that the Phase 2 construction
over the shallow depth of tailings will be viable. Confirmation
of the physical properties and suitability of the tailings will
be obtained prior to Phase 2 construction.
The final main embankment will have an ultimate crest
length of 1,900 feet and an ultimate elevation of 8,620 feet.
The maximum embankment height will be approximately 155 feet.

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