PERMFILE101223

• Permit No: M1977378
• IBM Index Class Name: Permit File
• Section_Exhibit Name: EXHIBIT A LEGAL DESCRIPTION CONT
• Media Type: D
• Archive: No

Once the slashers are set, the faces in the doq holes are
advanced to intersect the end raises to forma scram drift.
Pockets are driven into the footwall side of the scram on 25 foot
centers, raised up and belled out from hanging to footwall and
pocket to pocket to form the undercut. As soon as the undercut
is established, the raises are driven up to that level. At that
point, the prep phase is considered to be complete.
To avoid leaving pillars on the levels, some stopes are
prepared by driving a lateral drift parallel to the vein and then
driving cross-cuts back to the vein. The lateral is normally
driven on the footwall side and 30 feet off the vein.. The
location of the vein is established before the lateral is driven
by an exploration drift driven on the vein. Two back cuts are
taken out of the drift to make room for the swell from they first
shrink cut.
Two raises are started up on each end of the ore bloc:k from
the drift, and cross-cuts from the lateral are connected to the
raise bottoms for access during stoping, Crosscuts are then
driven on 30-foot centers from the lateral into the vein drift.
Waste rock from the pockets and lateral development is stacked in
the drift between the pocket opening. This reduces the amount of
waste rock that needs to be hauled from the area and hill the
area between pockets that cannot be reached with the LHD or
mucking machine. At this point, both shrink stops preparation
methods can proceed in similar fashion.
stoping commences by drilling and shooting a box cut just to
one side of the center raise. Subsequent rounds consist of
upside down bench blasting into the box cut advancirn3 along
strike in both directions toward the ends of the block. Rounds
are drilled with hand-held stopers using six-foot steel. After
every other cut, the raises are advanced to the nominal top of
the muck pile.
The stops is carried upward with nominal six-foot cuts off
of the back until the top of the oreshoot is reached or the
remaining drift sill pillar equals the vein width. In order to
maintain sufficient work room between the muck pile and the stops
back, approximately one third of the broken ore is drawn during
the stoping phase by selectively slushing the pockets on the
scram level.
Overhand Cut and Fill Stoping
Ore blocks are developed by driving an undercut drift (vein
width) along strike of the ore block.
Production stoping consists of filling the undercut with
waste rock fill and then breasting down ore on top of ttie fill.
LHDs work on top of the fill, and muck out the broken ore. After
the ore is removed, waste rock is placed in the void and another
breast cut is taken. Access to the area is maintained by
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