In the simulation process, it is found that the stability of the stope
after the third step is the worst.
With the advance of heading face, the hanging space of stope
continuously increases, to a certain degree, the overlying strata start to break from bottom to top, which forms the breaking arch [8-10].
Using a stoping dilution at 10% at zero grade and a stope
recovery of 80% mining studies estimated an extraction of 65% of this resource or 878,000 tonnes @ 7.95g/t Au (224,000 ounces) from development and stoping.
layout is standard in all mining areas with a stope
span of 23 m and a 7 m wide rib pillar.
45-13-0 produced lustrous disphenoids ([less than] 1 mm) intimately associated with sphalerite on gemmy clear quartz crystals.
Lack of mining flexibility required mining stopes
prior to completing ore control drilling which contributed to a lower than expected grade profile.
The company expects to have five stopes
in production on that level by the end of the fiscal year, which closes out on April 30.
Boart Longyear already has over 30 of its new generation stope
drill rigs operating in the platinum and chrome mines of southern Africa.
Of three stope
sizes analyzed, "the 23-m x 11-m long-hole open size was chosen to minimize the number of stopes
, it being the least costly of the options," McKirdy reported.
In massive open stoping areas, the sub-outcrop of the reefs coincides with reduced waste middling between the reefs, and this package of multiple, steep reefs lends itself to the creation of a large massive open stope
. The stope
shape has unsupported sloped sidewalls to improve safety and to channel the broken rock into the trough drive below.
AMC examined the existing fleet of stope
equipment (jumbos, LHDs, long-hole drills, and bolters) at the mine and established optimal drill-and-blast designs for the selected vein widths, dips, drift profiles (square and shanty), drift size (height and width), and mining methods, which could immediately be implemented to reduce dilution, without additional equipment purchases.