2010-12-08_PERMIT FILE - C1981008A ‎(12)‎

• Permit No: C1981008A
• IBM Index Class Name: Permit File
• Doc Date: 12/8/2010
• Doc Name: Backfilling and Grading
• Section_Exhibit Name: Section 2.05.4‎(2)‎‎(c)‎ Backfilling and Grading
• Media Type: D
• Archive: Yes

Table 2.05.4(2)(c) - WFC Property Topography Properties
The new surface drainage patterns for the WFC property are shown on Map 2.05.3(3) -1 -2.
Western Mining Area Backfilling Plan
The backfilling sequence for the New Horizon Mine west of 2700 Road is shown on both Map
2.05.3(3) -1 -2 and Attachment 2.05.4(2)(c) -7. The mining cuts from Attachment 2.05.4(2)(c) -7
correlate to the numbered cuts on Map 2.05.3(3) -1 -2.
The backfilling sequence has been designed to minimize the need for stockpiling of overburden
and material re- handling. For most of the mine sequence this is done with castblasting of the initial
overburden into the previously mined out open cut. The remaining overburden material is then
hauled from the new mining cut into the mined out cut. In most cases this leads to each cut
backfilling the one that precedes it (ex: Cut -92 material backfills Cut -91). However, as the shape
of the mining area changes (Cut -94 and Cut -95), not enough material is generated from new
excavation to backfill the previous cut.
In order to mitigate this problem, and ensure that post -mine topography is achieved, two things are
done. Firstly, the mining cut that needs more backfill than the next cut can generate will remain
"open" until enough material is generated by mining to successfully backfill. Secondly, backfill will
be hauled from a variety of cuts ahead of the "open" cut and used to fill the "open" cut. The source
cuts for backfill material can be seen in the Backfill Source column of Attachment 2.05.4(2)(c) -7.
(Revised June 2010) 2.05.4(2)(c) -7
Pre -Mine Topography
Post -Mine Topography
Average Elevation
5624
5604'
Maximum Elevation
5673
5575'
Minimum Elevation
5550
5560'
Average Land Slope
1 2.71%
12.61%
Steepest Slope
1 37.7%
27.6%
The new surface drainage patterns for the WFC property are shown on Map 2.05.3(3) -1 -2.
Western Mining Area Backfilling Plan
The backfilling sequence for the New Horizon Mine west of 2700 Road is shown on both Map
2.05.3(3) -1 -2 and Attachment 2.05.4(2)(c) -7. The mining cuts from Attachment 2.05.4(2)(c) -7
correlate to the numbered cuts on Map 2.05.3(3) -1 -2.
The backfilling sequence has been designed to minimize the need for stockpiling of overburden
and material re- handling. For most of the mine sequence this is done with castblasting of the initial
overburden into the previously mined out open cut. The remaining overburden material is then
hauled from the new mining cut into the mined out cut. In most cases this leads to each cut
backfilling the one that precedes it (ex: Cut -92 material backfills Cut -91). However, as the shape
of the mining area changes (Cut -94 and Cut -95), not enough material is generated from new
excavation to backfill the previous cut.
In order to mitigate this problem, and ensure that post -mine topography is achieved, two things are
done. Firstly, the mining cut that needs more backfill than the next cut can generate will remain
"open" until enough material is generated by mining to successfully backfill. Secondly, backfill will
be hauled from a variety of cuts ahead of the "open" cut and used to fill the "open" cut. The source
cuts for backfill material can be seen in the Backfill Source column of Attachment 2.05.4(2)(c) -7.
(Revised June 2010) 2.05.4(2)(c) -7