Stop Mining Haul Road Failures in Rainy Season
Key Takeaways:
- Rainy season road failures reduce mining output - Muddy and unstable haul roads increase cycle time, fuel use, maintenance costs, and cause missed production targets.
- Geosynthetics Significantly Improve Road Stability and Performance - Separation and subsurface drainage systems strengthen weak subgrades and maintain performance under heavy rainfall.
- Reinforced haul roads increase profitability - Indonesian mining case studies show productivity gains up to 26%, maintenance cost reductions around 22%, and substantial monthly profit increases. Proper haul road design is not an added cost but a strategic investment that enhances operational efficiency and financial performance.
Why Many Indonesian Mining Roads Fail During Rainy Season
In Indonesia, heavy rainfall significantly affects open-pit mining operations. When haul roads become wet, muddy, or unstable — especially during rainy seasons or in tropical climates — It will affects:
- Heavy trucks cannot maintain optimal speed
- Cycle time increases
- Fuel consumption rises
- Maintenance costs surge
- Production targets are missed
Poor haul road conditions directly reduce productivity and profitability. According to haul road management principles, road quality strongly influences truck speed, rolling resistance, and overall operational efficiency (Thompson & Visser, 2003).
The question is not whether rain will come.
The question is whether the road is engineered to withstand it.
Type of Geosynthetics Used In Mining Roads
Two main types of geosynthetics are widely applied in mining haul roads:
1. Geotextile (Separation + Reinforcement Layer)
Geotextiles prevent mixing between weak subgrade soil and aggregate base. They:
- Separate the structural base from weak subgrades
- Reduce mixing of soil and aggregate
- Distribute loads more evenly
- Extend road service life
Research confirms that woven geotextiles effectively reduced volumetric water content (VWC) in the subgrade and improved haul road stability under heavy loads (Araz et al., 2023).
2. Geonet (Drainage Layer)
Geonets function as subsurface drainage systems. They:
- Accelerate water flow horizontally
- Prevent water accumulation under road base
- Maintain soil strength during rainy seasons
Proper drainage is critical because excess pore water pressure drastically reduces soil shear strength (Koerner, 2005).
When combined, geotextile + geonet create a reinforced and well-drained road structure, which is essential for tropical mining environments.
Real Mining Case Studies in Indonesia
Case Study 1 – Gurimbang Mine Operation, PT. Berau Coal
A study on haul road improvement using geotextile at Gurimbang Mine showed measurable operational gains.
Results after geotextile installation:
- Truck speed increased by approximately 3 km/h
- Productivity increased by ~26%
- Monthly production rose from 43,821.63 bcm to 55,375.62 bcm
(Asof et al., 2023)
This demonstrates that improved road bearing capacity directly enhances hauling performance.
Case Study 2 – PT. Maruwai Coal
Another Indonesian mining study examined geosynthetic reinforcement (geocell-based system) on coal hauling roads.
Before reinforcement:
- Only 1.58 cycles/shift achieved
- Production loss ~26%
After reinforcement:
- Truck speed increased from 35.08 km/h to 38.66 km/h
- Production increased from 362,419 to 397,337 tons/month
- Maintenance costs reduced by approximately 22%
- Estimated profit improvement ≈ USD 8.24 million per month
(Raharjo et al., 2025)
This confirms that haul road reinforcement is not just a technical upgrade. It is a financial strategy.
How Better Haul Roads Increase Mining Profitability
Improved road engineering impacts mining operations in five major ways:
1. Faster Cycle Time
Higher average speed → more cycles per shift → more tonnage moved.
2. Lower Rolling Resistance
Smooth and stable roads reduce fuel consumption and tire wear (Thompson & Visser, 2003).
3. Reduced Maintenance Downtime
Less rutting means fewer grader interventions and road closures.
4. Lower Aggregate Requirement
Geosynthetics can reduce required base thickness, lowering construction cost (Koerner, 2005).
5. Extended Road Service Life
Reinforced roads last significantly longer than untreated roads under heavy traffic loads.
Why This Matters for Indonesian Mining Sites
Indonesia’s tropical climate presents unique challenges:
- High rainfall intensity
- Soft clay and peat soils
- Heavy off-highway trucks (>100 tons payload)
Without proper separation and drainage systems, road failure is inevitable during monsoon periods.
Using a geotextile + geonet system transforms haul roads from a recurring cost problem into a productivity asset.
Strategic Investment, Not Additional Cost
Many mine operators initially view geosynthetics as additional CAPEX.
However, the data shows:
- Productivity increase up to 26%
- Maintenance reduction around 22%
- Significant monthly profit improvement potential
In capital-intensive mining operations, even a 3–5% productivity gain can translate into millions of dollars annually. The documented cases show even higher improvements.
Proper haul road design should therefore be considered a profit optimization strategy, not merely an engineering decision.
Conclusion
Rainy season productivity loss is not unavoidable. It is often a road design problem.
Scientific studies and Indonesian mining case data demonstrate that using geotextile for separation and reinforcement combined with geonet for drainage can:
- Increase truck speed
- Improve production output
- Reduce maintenance cost
- Increase profitability
For mining companies operating in wet and soft soil conditions, geosynthetic-reinforced haul roads are no longer optional. They are a competitive advantage.
References
- Asof, M., Purbasari, D., & Agustian Putra, M. A. (2023). Perbaikan Jalan Angkut Menggunakan Geotextile untuk Meningkatkan Produktivitas HD 785 pada Site Gurimbang Mine Operation, PT. Berau Coal: Improvement of Hauling Road with Geotextile to Increase Productivity of HD 785 at Site Gurimbang Mine Operation, PT. Berau Coal. Cantilever: Jurnal Penelitian Dan Kajian Bidang Teknik Sipil, 12(1), 19-28. https://doi.org/10.35139/cantilever.v12i1.213
- Koerner, R. M. (2005). Designing with geosynthetics (6th ed.). Xlibris.
- Raharjo, O. F., Mudiyono, R., & Rochim, A. (2024). Inovasi Material Geosintetik (geocell) dan Kimia (geopoll) Untuk Optimalisasi Perbaikan Jalan Hauling di PT. Maruwai Coal. Wahana Teknik Sipil: Jurnal Pengembangan Teknik Sipil, 30(1). https://jurnal.polines.ac.id/index.php/wahana/article/view/6180
- Thompson, R. J., & Visser, A. T. (2003). Mine haul road maintenance management systems. Journal of the South African Institute of Mining and Metallurgy, 100(5), 303–312.
