A ground control management plan WA mines rely on is the single document that sets out how the mine identifies, designs for, monitors and responds to hazardous ground movement, and it is the centrepiece of the 2019 code of practice Ground control for Western Australian mining operations. Written under the old Mines Safety and Inspection Act 1994, it continues as a code under the Work Health and Safety Act 2020, but the duties it supports now sit in the Work Health and Safety (Mines) Regulations 2022, chiefly regulation 631B on geotechnical structures and regulations 627 to 629 on principal mining hazards.
This guide is for open pit and underground mines. It covers the code and guideline and their legal weight, maps the code to current regulation numbers, and sets out plan content, inspections, monitoring and trigger action response plans (TARPs). Quarry faces and batters are covered separately in our guide to the ground control management plan for a quarry.
Why ground control is regulated so closely
The 2019 code lists the ways hazardous ground movement injures or kills people: falling rock, wall failure and rock ejection, falls from height when an edge or excavation gives way, and entrapment when a sand pile collapses or a backfilled stope subsides. The code also names waste rock landforms, tailings storage facilities and ore stockpiles, not just pit walls and underground excavations.
The regulations match that breadth: under regulation 5 a “geotechnical structure” includes embankments, foundations, waste dumps, ore stockpiles, trenches, tailings storage facilities and underground and surface openings, so the geotechnical hazards at a WA mine are wider than the pit.
The 2019 code and guideline, and the weight each carries
Two WorkSafe documents cover the subject, with different legal standing.
The code of practice
Ground control for Western Australian mining operations: code of practice was published by the then Department of Mines, Industry Regulation and Safety in 2019. It is about seven pages, applies to all mines from sand pits to deep underground operations, and is built around a ground control management plan (GCMP) and the safe systems of work that sit under it.
WorkSafe lists it under transitional codes of practice. Section 420 of the Work Health and Safety Act 2020 provides that a code in effect under the old Act immediately before commencement day continues as if approved under section 274. That gives it section 275 weight: in a prosecution the code is admissible as evidence of whether a duty was complied with, and a court may rely on it to decide what was reasonably practicable. A mine can still show compliance another way that gives an equivalent or higher standard.
The guideline
Ground control management in Western Australian mining operations: guideline, also from 2019, is the long companion at about 29 pages. It explains how to build and run a GCMP, including monitoring, TARPs, hazard maps and an example plan structure. As a guideline, not a code, it has no section 275 status. It still matters, because under section 18 what an operator ought reasonably to know about a risk and its controls is part of what is reasonably practicable.
The catch: both cite repealed regulations
Both documents were written under the Mines Safety and Inspection Act 1994 and its 1995 regulations, and their legislation appendices list the old regulation numbers. Those numbers are no longer law. Read the technical content of the code and guideline as current good practice, and take the legal duties from the 2022 regulations.
What the 2022 regulations require
The Work Health and Safety (Mines) Regulations 2022 deal with ground in three layers: a specific duty for every mine, a heavier regime where ground instability is a principal mining hazard, and inspection and reporting duties around both.
Regulation 631B: geotechnical structures at every mine
In complying with regulation 617, the mine operator must manage the risks associated with the instability or failure of geotechnical structures. Regulation 631B(2) lists the matters the operator must have regard to, including:
- geological structures, the hydrological environment and their influence on stability
- design, location, construction and maintenance of geotechnical structures
- properties of the material
- operational factors and their influence on stability
- design, installation, quality control and maintenance of ground support and reinforcement
- design life
- inspection and monitoring
- competency of designers, planners, supervisors and operators.
Regulation 631B(3) applies the duty to design, construction, operation, maintenance and closure, so ground control is a life of mine obligation.
Regulations 612 and 627 to 629: ground as a principal mining hazard
Regulation 612(2)(a) names geotechnical structure instability as something that may be a principal mining hazard. The test in regulation 612 is a reasonable potential to cause multiple deaths in a single incident or a series of recurring incidents. Not every bench is a principal mining hazard, but a high pit wall above a busy ramp or a large underground opening may well meet the test. The wider rules are in our explainer on principal mining hazards in WA.
Where it is one, the operator must identify it and run a comprehensive and systematic risk assessment (r 627), prepare a principal mining hazard management plan (r 628) and review it when a control is revised (r 629). Regulation 628(3) requires, among other things, a record of the risk assessment, all control measures, the technical standards relied on, and the reasons for adopting or rejecting each control considered. Schedule 19 clause 1 adds matters specific to geotechnical structure instability, among them ground stresses, water and oxidation, seismic activity and its monitoring, procedures for emergencies due to ground failure, and how inspection and monitoring data is collected and analysed. The plan mechanics are explained in our guide to the principal mining hazard management plan in WA.
Regulation 634A: workplace inspections
The mine operator must have arrangements for regular workplace inspections, based on a risk assessment of the workplaces. The arrangements must set the procedures, when inspections happen, the competence required and how many competent people are needed. Inspections are carried out by the statutory supervisor where one is appointed for the place, by the underground supervisor where one is appointed, and otherwise by a competent person the operator appoints. See our guide to the statutory supervisor role in WA.
Regulation 675V: reporting ground events
The regulation 5 definition of a reportable incident includes a significant seismic event and extensive subsidence. Damage to plant or a structure that impedes its safe operation is also on the list. The mine operator must take all reasonable steps to notify the regulator in writing, in the approved form, as soon as possible after becoming aware of one. Notifiable incidents under the Act are a separate tier; both are covered in notifiable and reportable incidents at WA mines.
Mapping the code to current regulation numbers
Because the code still points at the 1995 regulations, anchor each GCMP element to a current duty. Our reading of the main links:
| Code element | Current duty it supports |
|---|---|
| Hazard and risk register; risk-based approach | r 617 (risk management), r 627 (PMH identification and risk assessment) |
| Ground control management plan | r 631B; r 628 and Schedule 19 cl 1 where ground instability is a PMH |
| Geotechnical model and safe design | r 631B(2)(a) to (c) and (f); r 628(3)(h) design principles and standards |
| Design implementation and ground support | r 631B(2)(b) and (e) |
| Monitoring, TARPs, review and validation | r 631B(2)(g); Schedule 19 cl 1(l) and (o); r 629 review |
| Workplace inspections | r 634A |
| Communication, training and supervision | r 631B(2)(h); r 628(3)(g) information and training |
| Incident reporting | r 675V and the regulation 5 reportable incident definition |
What a ground control management plan should contain
The code says the GCMP should be a single, overarching, easily accessible and easy to follow document, developed and maintained by competent persons, with detail scaled to the operation. A deep, geologically complex underground mine needs far more than a shallow sand pit. Drawing on the code and guideline, a plan for an open pit or underground mine should cover:
- Hazard and risk register. The foundation of the plan, reviewed through the life of the mine as operations expand or the risk profile changes.
- Roles and responsibilities. Who owns the geotechnical model, the GCMP, design input, verification, audit and training.
- Geotechnical model. Engineering properties of all materials and structures that influence the design, split into domains, updated as mining exposes more ground.
- Design methods and acceptance criteria. The methods used, the factor of safety or acceptable residual risk, the assumptions, and the justification, with more conservatism where uncertainty is higher.
- Sign-off protocol for key design elements.
- Design implementation. Drill and blast to design intent, ground support selection, installation and quality control, scaling, backfill, sequence and rate of extraction.
- Monitoring. What is measured, by instrument or observation, and the tolerance limits that mean something is wrong.
- TARPs for ground movement beyond the site’s tolerance limits.
- Safe systems of work. Procedures, work instructions and training requirements, included or referenced.
- Review triggers. After an incident or unexpected movement, before a change to design or methods, and when ground conditions change.
- Records and document control. Monitoring results, inspections, audits, incidents and the actions taken, with previous versions retrievable.
Where ground instability is a principal mining hazard, the same document can serve as, or sit inside, the principal mining hazard management plan, provided it meets every item in regulation 628(3) and Schedule 19 clause 1. One item a plan written to the code alone can miss is the reasons for rejecting controls that were considered.
Inspections, monitoring and TARPs in practice
Slope stability at WA mines is managed day to day through three linked activities.
Inspections
The guideline treats a visual workplace inspection before each shift as the minimum, but that minimum came from the repealed 1995 regulations. It also expects the frequency and depth of inspection to match the rate of mining and the potential consequences at each location. Regulation 634A sets no fixed frequency: the arrangements must rest on the operator’s risk assessment, so a cracking wall justifies tighter inspection than a stable, mined-out batter. For the field detail of a wall inspection, see our highwall inspection checklist.
Monitoring
The guideline notes that visual observation alone may not give enough warning for some failure mechanisms. It describes simple, robust equipment such as survey pins or crack monitors, combined with regular recorded visual observations, as appropriate for most mines as a starting point, scaling up to instrumented systems where the risk demands it. Monitoring verifies design assumptions and warns when tolerance limits are approached or exceeded, so people can be withdrawn in time.
TARPs
According to the guideline, a ground control TARP should have a clear purpose, address all potential outcomes of the relevant ground movements, define the monitoring, triggers and actions clearly, align with the site’s emergency arrangements, assign clear roles, and be available to and executable by everyone involved. It should be reviewed when ground conditions, systems of work, plant or designs change. A worked example of trigger levels is in our guide to digital TARPs in mining.
The guideline also recommends regularly updated geotechnical hazard maps to plan inspections and set site-specific TARP actions.
Where ground control management breaks down
- The GCMP is a design document nobody in the pit reads. The code wants a single, easily accessible, easy to follow document, not one filed with the geotechnical engineer.
- Old regulation numbers survive. A plan that still cites the 1995 regulations suggests to an inspector that it has not been reviewed since 2022.
- The TARP and the monitoring do not match. Nobody can say which level the wall is at right now.
- Inspections record the form, not the ground. A ticked “walls OK” carries no location and no photo.
- No review after the event. A minor failure is cleaned up without the back analysis and model update both documents call for.
- Reportable events go unrecognised. Nobody has decided in advance what “significant” seismicity or “extensive” subsidence means at this mine, so the regulation 675V call is made late or not at all.
Keeping the plan live on the mine map
Most of those failures come from the plan, the monitoring and the inspections living in different places: the TARP with the geotechnical engineer, the radar on its own screen, the inspection on paper in a ute.
HazView puts them on one interactive map of the site, over survey DXFs, drone imagery and hillshade. A wall or zone can carry a geotechnical TARP rating, for example levels 1 to 4, and an area state of open, restricted or closed, so everyone on site sees the current level at the place it applies. Slope monitoring radar can be shown on the map with its status history. Wall inspections use the site’s own forms, completed offline if needed and pinned to the location or attached to the hazard, with photos and comments on each question. TARP levels can sit in the answer options, so the TARP outcome comes straight from the inspection, and conditional logic opens an escalation section when an answer is non-conforming. Controls carry an owner, due date and status, and the hazard register exports to CSV or JSON for the review.
See how this works for the people who own the plan on HazView for geotechnical engineers, or book a demo with your own TARP and inspection forms. For the wider WA framework, return to our guide to quarry and mine safety in Western Australia.
Frequently asked questions
Is there a current ground control code of practice in WA?
Yes. Ground control for Western Australian mining operations (2019) is listed by WorkSafe as a transitional code of practice. Under section 420 of the Work Health and Safety Act 2020 it continues as if approved under section 274, so it carries evidentiary weight in a prosecution. Read its old regulation references against the 2022 Mines Regulations.
Is a ground control management plan mandatory in WA?
The regulations do not use the term GCMP. Regulation 631B requires every mine operator to manage the risks of geotechnical structure instability, and where that instability is a principal mining hazard, regulation 628 requires a written principal mining hazard management plan. The code sets out a GCMP as the way to meet those duties. A mine that takes a different approach should be able to show it gives an equivalent or higher standard.
Is every pit wall a principal mining hazard?
No. Geotechnical structure instability is a principal mining hazard only where it has a reasonable potential to cause multiple deaths in a single incident or a series of recurring incidents. The operator must identify which ones meet that threshold under regulation 627; every geotechnical structure is still covered by regulation 631B.
Does the ground control guideline have the same weight as the code?
No. The guideline is not a code, so section 275 of the Act does not apply to it. It is still relevant, because what a mine operator knows or ought reasonably to know about ground risk and its controls feeds into what is reasonably practicable under section 18.
Do ground falls have to be reported to WorkSafe?
Some do. A significant seismic event and extensive subsidence are reportable incidents under regulation 5, as is damage that impedes the safe operation of plant or a structure. The mine operator must notify the regulator in writing as soon as possible under regulation 675V. A death, a serious injury or a dangerous incident, which includes the collapse or failure of an excavation, is a notifiable incident under the Act and must be notified immediately under section 38.