The Hidden Cost of Poor Geomechanical Modelling in Underground Mines

Underground mining is complex, high-risk, and capital intensive, yet many operations still rely on outdated or overly simplified geomechanical models. The consequences? Unexpected events, safety incidents, poorly design ground support, and potentially millions in lost productivity.*

At NEMCCO, we’ve supported mines across the globe and seen firsthand how poor geomechanical modeling silently erodes operational performance and how advanced numerical tools can reverse that trend.

Common Mistakes in Mine Site Modeling

1. Oversimplified Assumptions: Many sites still use 2D modeling or empirical charts to guide support design, ignoring complex stress redistributions in deep or irregular geometries.

2. One-Time Models That Age Poorly: A model built and often remains untouched for years, even as mining progresses and new data becomes available.

3. Poor Calibration with Field Data: When modeling isn’t validated against visual observations, ground surveys, seismic data, or Oreizon's data you get mismatches that reduce predictive power.

4. Tool Limitations: Generic tools not purpose-built for geomechanics (like CAD overlays or spreadsheet calculators) lack the resolution and physics to capture true ground behavior.

The Cost of Getting It Wrong

Poor modeling is rarely the direct cause of incidents, but it often plays a hidden role behind:

• Unexpected rockbursts due to poorly designed mine plans and sequence

• Over-designed support systems, adding cost and time

• Production delays, caused by unanticipated rehabs

• Stope dilution issues

A single ground control failure can cost hundreds of thousands in downtime, not to mention the reputational and safety impact.

What Better Modeling Looks Like

Our modeling approach focuses on site-specific, 3D-calibrated, and operationally useful outputs. We use tools like FLAC3D, IMAT, RS2, RS3, and Map3D to model:

• Stress redistribution around voids, drives, and pillars

• Seismic response to excavation sequences

• Backfill interaction with stope walls and barricades

• Support performance under actual loading conditions

We don’t just deliver a model, we build a workflow of best practices and provide decision-ready insights.

 A Real-World Example

At a deep narrow-vein gold mine in Latin America, ground support was performing poorly early in the mine sequence, and costs were escalating (rehab work). The original models underestimated the influence of adjacent mined-out zones.

NEMCCO:

• Conducted a FLAC3D model to evaluate high risk areas

• Calibrated it using field data

• Identified overstressed pillars between stopes

• Proposed a modified mining sequence with localized reinforcement

Result:

• 40% drop in unplanned rehab

• 18% reduction in bolt & mesh costs

• Improved safety compliance with regulator

The Bottom Line

In mining, you can’t eliminate uncertainty, but with better geomechanical modeling, you can manage it.

NEMCCO helps mines reduce risk, optimize design, and extend the life of their assets through advanced modeling, field-calibrated data, and decades of real-world experience.

Need a second opinion on your current models or support design?

Contact us at info@nemcco-international.com or visit www.nemcco-international.com