PERMFILE60741

• Permit No: M2006080
• IBM Index Class Name: Permit File
• Doc Date: 2/23/2007
• Doc Name: Response to Adequacy Review Comments of January 31, 2007
• From: WSI
• To: DRMS
• Media Type: D
• Archive: No

6.4.4 Exhibit D -Mining Plan
Water Diversions and Impoundments
Water diversions will include pumping groundwater from dewatering trenches in
Phase I -Cell 4 and precipitation inflows into the mine cells into a sediment pond
before discharging to the river. The location of the sediment pond, shown in
Exhibit C-2 -Mining Plan, may change during the mining processes such that
the sediment pond will always be located in between the current mining operation
and the river.
Timetable and Size of Mining Areas
The mining operation is expected to last for 15-20 years; however this could vary
depending upon market conditions. The approximate size of areas to be worked
at any one time generally correlates to the size of the mining cells. The
exception is on the East Pit when Cell 3 will be partially mined during the non-
flood season concurrently with mining of Cell 1. Table 6.4.4-2 shows the mining
cell size and the approximate timetable for working each cell.
Table 6.4.4-2. Mining Timetable
Mining Phase
and Cell Area
(acres) Approximate
Time Complete
Each Cell
(years) Approximate
Cumulative Time
Until Complete
(years)
Phase I -Cell 1 9.4 1.5 - 2 1.5 - 2
Phase I -Cell 2 29.9 4,5 - 5 6- 7
Phase)-Cell3 13.7 2-2.5 8-9.5
Phase I -Cell 4 13.1 2 - 3 10 - 12.5
Phaseil-Cell1 12.2 2-2.5 12-15
Phase II -Cell 2 9.1 1.5 - 2 13.5 - 17
Phase I I -Cell 3
(seasonal mining) 11 4 2- 3 15.5 - 20
TOTAL 99 -- 15.5 - 20
February 20, 2006 Bokelman/Walters Pit
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