Quarry geotechnical services cover the full lifecycle of quarry operations, from exploration and resource estimation through to extraction, slope management, and rehabilitation.
What Are Quarry Geotechnical Services?
Quarry geotechnics applies geotechnical engineering principles to the design, operation, and closure of quarries. Key activities include:
- Geological modelling and resource estimation
- Quarry slope design and stability analysis
- Blast design and vibration monitoring
- Rock quality assessment and QA/QC
- Bench and haul road design
- Stockpile management
- Rehabilitation planning
Exploration and Resource Assessment
Geological Modelling
| Activity | Purpose |
|---|---|
| Geological mapping | Map rock types, structure, weathering |
| Drilling programs | Assess resource extent and quality |
| Geophysical surveys | Map resource boundaries and overburden depth |
| Bulk sampling | Verify material quality for intended use |
Resource Reporting (JORC Code)
Quarry resources in Australia must be reported in accordance with the JORC Code (Australasian Code for Reporting of Exploration Results, Mineral Resources and Ore Reserves).
| Category | Confidence Level | Required Work |
|---|---|---|
| Measured | High | Detailed drilling, comprehensive testing |
| Indicated | Moderate | Sufficient drilling for geological continuity |
| Inferred | Low | Limited sampling, estimated continuity |
Quarry Design
Slope Design
Quarry slopes must be designed for stability over the life of the operation:
| Slope Element | Design Parameter | Typical Values |
|---|---|---|
| Bench height | Height of individual mining level | 5–15 m |
| Bench face angle | Individual bench slope | 60–85° |
| Overall slope angle | From crest to toe of final wall | 30–55° |
| Haul road width | Road width for truck operation | 10–25 m |
| Berm width | Catch bench width between benches | 4–10 m |
Slope Stability Analysis
| Analysis Method | Application |
|---|---|
| Kinematic analysis | Wedge, planar, toppling failure in jointed rock |
| Limit equilibrium | Circular/non-circular failure through soil/rock mass |
| Finite element / distinct element | Complex geology, discrete fracture networks |
Monitoring
| Method | Purpose | Frequency |
|---|---|---|
| Prism surveys | Wall movement monitoring | Weekly to monthly |
| Radar (SSR or InSAR) | Real-time slope movement | Continuous |
| Inclinometers | Deep-seated movement | Monthly |
| Crack monitoring | Surface crack propagation | Weekly |
| Groundwater piezometers | Pore pressure management | Continuous or weekly |
Rock Quality Assessment
QA/QC for Product Quality
| Test | Standard | Purpose | Typical Requirement |
|---|---|---|---|
| PSD (grading) | AS 1141.11 | Product size compliance | Customer specification |
| Los Angeles abrasion | AS 1141.23 | Wear resistance | < 30% (base course) |
| Wet-dry strength | AS 1141.22 | Weathering resistance | < 35% variation |
| Flakiness index | AS 1141.14 | Particle shape | < 25% (concrete aggregate) |
| Point load index | AS 4133.4.2.1 | Strength screening | > 2.0 MPa |
| Petrographic analysis | AS 1141.60 | Mineralogy, potential ASR | ASR-reactive minerals |
Stockpile Management
- Stockpile base preparation (drainage, compaction)
- Layered placement for homogeneity
- Sampling at time of loading for quality verification
- Moisture management (cover or sprinklers for dust)
Blast Design and Vibration Control
Blast Design Parameters
| Parameter | Description | Typical Range |
|---|---|---|
| Hole diameter | Drill hole size | 75–150 mm |
| Burden | Distance from hole to free face | 2–5 m |
| Spacing | Distance between holes in a row | 2.5–6 m |
| Stemming | Length of inert fill at top of hole | 2–4 m |
| Powder factor | Explosive per tonne of rock | 0.2–0.6 kg/t |
Vibration Monitoring
Blasting vibrations are monitored to comply with:
| Standard | Limit (PPV) | Structure Type |
|---|---|---|
| AS 2187.2 | 25 mm/s | Residential buildings |
| AS 2187.2 | 50 mm/s | Commercial / industrial |
| DIN 4150 | 20 mm/s | Historical / sensitive |
| USBM RI 8507 | 12.5–50 mm/s | Depends on frequency |
Air Overpressure Monitoring
| Level (dB Lin) | Effect |
|---|---|
| < 115 | Generally undetectable |
| 115–125 | Noticeable, acceptable |
| 125–133 | May cause complaints |
| > 133 | Potential structural damage |
Environmental and Regulatory Compliance
Environmental Approvals
| Requirement | Regulation |
|---|---|
| Development consent | State planning legislation |
| Environmental Impact Statement | Depending on scale and location |
| Water management plan | State EPA requirements |
| Air quality (dust) management | EPA licence conditions |
| Noise management | EPA licence conditions |
| Groundwater monitoring | If below water table |
Rehabilitation Planning
| Phase | Activity |
|---|---|
| Active operations | Progressive rehabilitation of completed areas |
| Final landform design | Contouring for drainage, final slopes |
| Vegetation establishment | Native species, erosion control |
| Monitoring and maintenance | Weed control, slope stability, drainage |
Australian Standards
| Standard / Code | Title |
|---|---|
| AS 2187.2 | Explosives — Storage and use |
| AS 4133 Series | Rock testing methods |
| AS 1141 Series | Aggregate testing methods |
| AS 1726-2017 | Geotechnical site investigations |
| JORC Code (2012) | Mineral resource and ore reserve reporting |
| ANCOLD Guidelines | Water management (quarry ponds) |
| State EPA Guidelines | Quarry environmental management |
Frequently Asked Questions
What is the typical life of a quarry?
Quarry life ranges from 10–50+ years depending on resource size, extraction rate, and market demand.
How is final wall angle determined?
The final wall angle is based on geotechnical assessment including rock mass strength, discontinuity orientation, groundwater conditions, and required safety berms. Typically 40–65° for the overall slope.
What is a catch berm?
A catch berm is a horizontal bench left between vertical benches to catch falling rocks. Berm width is typically 4–10 m, determined by bench height and slope angle.
Do quarries need groundwater monitoring?
If quarrying extends below the water table, groundwater monitoring (piezometers, pumping records, water quality) is required for environmental compliance and slope stability assessment.