Ground or strata instability is a major factor in mine collapse and poses a serious hazard. This guidance is for mine operators, site senior executives, mine managers, and anyone else involved in managing instability.

While this guidance has not been updated to reflect current work health and safety legislation (the Health and Safety at Work Act 2015 and regulations), it may still contain relevant information and practices to keep workers and others healthy and safe.

Please read this guidance in conjunction with all relevant industry standards that apply to you as a PCBU. This guidance will be progressively reviewed and either updated, replaced with other guidance, or revoked.

This document sets out our expectations for managing ground or strata instability in underground mining and tunnelling operations instability. It includes information on:

  • causes of ground or strata instability
  • geotechnical assessment
  • design and implementation of control measures
  • monitoring controls
  • review and audit requirements.

This information contributes to the contents of the ground or strata instability principal hazard management plan (PHMP).

ACOP: Ground or strata instability in underground mines or tunnels (PDF 2.4 MB)

Developing a PHMP for ground or strata instability

These guidelines list the minimum information required for the PHMP – it provides an example of how to produce a PHMP, rather than a template that must be followed. 

Developing a ground or strata instability principle hazard management plan (PDF 366 KB)