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Report – Mining – Inundation or inrush of a substance – September 2025 to June 2026

This report provides the findings of an assessment program at tailings dams, water storages or waste tips at Coal and METEX mines focussing on inundation or inrush of a substance.

Sector Coal and METEX mines
Principal hazard plan Inundation or inrush of a substance
Material unwanted event Uncontrolled movement of tailings dams, water storages or waste tips
Topic Inundation or inrush of a substance

Operation type assessed

Operation type Number of mines assessed
Surface 22
Total 22

Criteria assessed

Critical control Criteria
The tails facility (tailings emplacement) or water storage is designed to a recognised standard (e.g. ANCOLD)  How has the mine ensured that tails facilities are designed and constructed to the required standard?
Reduce the magnitude of the source (i.e. reduction of reject/waste and/or treatment of reject/waste  Has the mine considered systems to reduce reject/waste material generation or treat reject/waste material?
Water management system How does the mine ensure their water management system remains fit for purpose and operating correctly?
Workers are restricted from accessing tailings storage facility (TSF)  Workers are restricted from accessing TSF
Onsite emergency management Does the mine have adequate systems to response to an emergency related to tails and water storage facilities?

Findings with issues identified

Critical control Criteria Findings of concern Findings of contravention Findings of immediate concern Total findings with issues
The tails facility (tailings emplacement) or water storage is designed to a recognised standard (e.g. ANCOLD)  How has the mine ensured that tails facilities are designed and constructed to the required standard? 0 1 1 2
Reduce the magnitude of the source (i.e. reduction of reject/waste and/or treatment of reject/waste  Has the mine considered systems to reduce reject/waste material generation or treat reject/waste material? 0 0 0 0
Water management system How does the mine ensure their water management system remains fit for purpose and operating correctly? 1 1 1 3
Workers are restricted from accessing TSF Workers are restricted from accessing TSF 0 0 0 0
Onsite emergency management Does the mine have adequate systems to response to an emergency related to tails and water storage facilities? 0 1 1 2
Total   1 3 3 7

Compliance notice type issued during the program

Notice type Notices 

Percentage of notices issued

WHS(MPS)A s23 notice of concerns 5

36%

WHSA s191 improvement notice 7

50%

WHSA s195 prohibition notice 2

14%

Total 14

100%

A total of 14 compliance notices were issued to 6 mines.

Note: This data represents all notices issued during the program and may include notices other than inundation or inrush topics.

Recommendations

Operators of coal and METEX mines managing the potential for uncontrolled movement of tailings dams, water storages or waste tips should review their site principal hazard inundation or inrush management plan and the critical controls assessed for the topic of inundation or inrush of a material or substance.

  • Review ANCOLD Tailings Dam Guideline 2019 for relevant testing and analyses to determine the overall Factor of Safety (FOS) of each wall section. Determine if the FOS is appropriate for the risk/consequence guidelines provided in ANCOLD 2019.
  • Ensure edge protection controls are suitable and fit for purpose to prevent mobile plant entering water bodies.
  • Review the risk controls for worker exposure to inrush and inundation hazards and workers working alone at tailings storage facilities (TSFs).
  • Ensure a plan is provided in the trigger action review plan (TARP) with dam break run out zones, evacuation routes and muster points (outside the dam break zones).
  • Ensure the registered tailings facility engineer and accountable persons receive applicable training in construction, monitoring and maintenance of TSFs.
  • Undertake regular mock emergency response scenarios with relevant stakeholders, including potential down-stream stakeholders.
  • Review the updated NSW Code of Practice: Inundation and inrush hazard management (April 2026) (PDF, 621.09 KB). The Code has been updated to reflect amendments to legislation.