Specialized Operations

Underground
Mining

Deep rock extraction utilizing mechanized narrow-vein and bulk mining methodologies. Precision operations in challenging geologies with comprehensive ground support and ventilation management.

3,500m Max Depth Capacity
1.2m Minimum Vein Width
98.5% Ore Recovery Rate
24/7 Continuous Operations
01

Narrow Vein Mining

Specialized extraction for orebodies less than 3 meters in width, requiring surgical precision to minimize waste dilution. Our mechanized approach utilizes single-boom and twin-boom electric hydraulic jumbos capable of drilling 45mm to 64mm blastholes in headings as narrow as 1.2 meters.

Ground support installs concurrently using mechanized bolters with resin-grouted rebars and mesh screen systems. Mucking operations employ 2-yard to 4-yard LHDs (Load-Haul-Dump units) with remote control capability, removing operators from unsupported ground.

  • Mechanized drilling: 150-200 meters per shift
  • Dilution control: <15% waste rock inclusion
  • Ground support: Combination bolts, mesh, and shotcrete
  • Ventilation: Auxiliary fans and ducting systems
  • Haulage: Electric downhill tramming to main declines

Applications include high-grade gold-quartz veins, epithermal deposits, and steeply dipping base metal sulphides where selectivity is paramount to economic viability.

Narrow Vein Mining Operations
02

Longhole Stoping

Massive mining method utilizing downhole drilling equipment to create large stopes with minimal development requirements. Stoping widths range from 4 meters to 20 meters, utilizing parallel blastholes up to 40 meters in length.

Ring drilling patterns are established from upper levels, with ore drawn from lower extraction levels. This vertical retreat mining minimizes personnel exposure while maximizing production rates of 500 to 1,500 tonnes per day per stope.

  • Drilling: ITH percussion rigs and top hammer systems
  • Blasthole diameter: 89mm to 127mm
  • Stope support: Cable bolts and cemented fill
  • Extraction: Remote-controlled LHDs and ore passes
  • Dilution: 10-20% depending on wall stability

Cost-effective for steeply dipping, consistent orebodies where large-scale mechanized operations outweigh the capital costs of extensive development.

Longhole Stoping Method
03

Cut & Fill

Flexible overhand mining suitable for irregular, steeply dipping orebodies where controlled extraction sequencing is required. Operations progress upward in horizontal slices (cuts) of 2.5 to 3 meters, with each cut backfilled to create the working floor for the subsequent lift.

Backfill systems utilize either pastefill (cemented aggregate slurry) or hydraulic fill with depository farms on surface. Fill retention is provided by paste walls or timber/steel bulkheads.

  • Drilling: Jumbos and rising drills for breasting
  • Mucking: 6-yard LHDs in main levels
  • Fill placement: Reticulation system from surface
  • Recovery: Sequential extraction with 85-90% recovery
  • Support: Point-anchored resin bolts and mats

Ideal for high-grade, irregular deposits where maximum recovery takes precedence over bulk production rates.

Cut and Fill Mining
04

Room & Pillar

Horizontal mining methodology for flat-lying or gently dipping deposits, creating a grid pattern of excavated rooms (7m to 12m wide) separated by supportive pillars. Pillar size is calculated based on overburden depth and rock mass rating to ensure long-term stability.

Mechanized room-and-pillar utilizes continuous miners or drill-and-blast cycles with shuttle cars and feeder breakers. For harder formations, we employ remote-controlled surface drills with precisely timed blasts.

  • Extraction ratio: 60-75% depending on depth
  • Pillar design: Square or herringbone patterns
  • Ventilation: Intake/return drift systems
  • Haulage: Battery-powered trucks or conveyor belts
  • Roof support: Bolts, cables, and steel mats

Suited for potash, limestone, coal, and stratiform base metal deposits where surface subsidence must be strictly controlled.

Room and Pillar Mining
05

Shrinkage Stoping

Overhand mining technique where broken ore remains in the stope to support walls while providing a working platform for subsequent lifts. Approximately 60% of broken ore supports wall stability during extraction; the remaining 40% is withdrawn from drawpoints at the stope base.

Miners drill blastholes upward from the broken ore cushion into the stope back. After blasting, the swell (volume expansion of broken rock) provides headroom for the next drilling cycle.

  • Drilling: Air-leg or hydraulic rigs from broken ore
  • Mucking: Remotely operated LHDs from drawpoints
  • Recovery sequence: Final withdrawal after completion
  • Dilution: 15-25% from wall sloughing
  • Geology requirement: Competent host rock essential

Applied to steep, narrow veins with competent walls where mechanized cut-and-fill is uneconomical, though less common due to safety considerations.

Shrinkage Stoping Method
06

Vertical Crater Retreat

Highly mechanized bulk mining method utilizing large-diameter blastholes (165mm-270mm) drilled from upper levels downward. Cratering charges break successive vertical benches, with ore mucked from underlying extraction levels.

VCR eliminates the need for drilling within the stope, maximizing operator safety while achieving production rates exceeding 2,000 tonnes per day. Bench heights typically range from 3 to 5 meters.

  • Drilling: Down-the-hole (DTH) drills from surface or upper levels
  • Blasthole pattern: Ring or parallel arrangements
  • Charging: pneumatic loading of ANFO or emulsion
  • Mucking: Remote 10-yard LHDs in extraction crosscuts
  • Support: Cable bolts for hanging wall reinforcement

Exclusively applied to massive, steeply dipping orebodies with consistent grade, where safety and productivity outweigh high capital drilling requirements.

Vertical Crater Retreat Mining

Specialized Equipment

Underground-specific machinery engineered for confined spaces and high-stress environments.

Jumbo Drill Electric

Two-Boom Jumbo

Twin-arm hydraulic drilling rig for development headings and production drilling with precision positioning.

45-64mm
5.5m
LHD Loader Diesel/Electric

Load-Haul-Dump

Articulated underground loaders with remote operation capability for mucking in unsupported ground.

6-14yd
18km/h
Shotcrete Sprayer Robotic

Shotcrete Sprayer

Robotic spraying systems for rapid ground support application with consistent thickness and minimal rebound.

30m³/h
15m
Underground Safety Systems

Zero Harm Philosophy

Underground operations demand uncompromising safety protocols. Our systems integrate real-time gas monitoring, refuge chambers, and emergency response infrastructure.

Ground Support

Immediate support installation protocols with retractable检视 platforms and mechanized bolters. Mandatory resin-grouted bolts within 1.5 tunnel diameters of the face.

Ventilation Control

Forced auxiliary ventilation with 0.25 m³/s per kW of diesel power minimum. Continuous methane and diesel particulate monitoring with automatic alarm systems.

Emergency Systems

Refuge chambers every 300 meters of development, stocked with 96 hours of breathable air, communications, and medical supplies. Dedicated rescue teams at every operation.

Communications

Leaky feeder radio systems providing 100% coverage, plus tracking tags for all personnel with real-time location monitoring in the control room.

Ready to Go Underground?

Discuss your deep-rock extraction challenges with our technical team. We provide feasibility assessments, method selection analysis, and full operational mobilization.

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