Using adaptive management plans to manage risk in Queensland coal seam gas projects

CASE STUDY

There are three major coal seam gas projects under way in southern Queensland which are closely monitored by the federal and the Queensland Governments.

Under the federal conditions of approval, each project has detailed water monitoring and management plans which are carefully scrutinised by Departmental officers and other experts. Queensland has a regulatory framework to support the responsible development of the coal seam gas industry. The monitoring systems put in place federally are designed to complement the management arrangements put in place by the Queensland Government’s Office of Groundwater Impact Assessment.

The Office of Groundwater Impact Assessment has now undertaken a significant body of work around coal seam gas. It has completed a cumulative assessment of the impacts of coal seam gas water extraction and developed integrated regional management arrangements in its Surat Underground Water Impact Report. The Surat report includes:

  • maps of predicted water level impacts
  • a water monitoring strategy
  • a management strategy for springs that could be affected by falls in water levels
  • assigned responsibilities for individual coal seam gas operators.

In line with an adaptive management approach, these plans are revised at least every three years to include the updated modelling and research findings from the Surat Underground Water Impact Report. Where matters protected by national environment law are not completely protected by state or territory government conditions, the proponent must still undertake additional monitoring and risk prevention activities.

The water management plans are based on strict industry codes of practice and national guidelines, including:

Conditions imposed under national environment law do not just protect our water resources but also the unique animals and plants that are found in these environments. That is why the federal approvals for these projects do not allow coal seam gas activities to have any adverse impact to ‘the community of native species dependent on natural groundwater discharge from the Great Artesian Basin ’. Almost 80 animal and plant species are known to only occur in Great Artesian Basin springs.

The Queensland Surat report contains a water monitoring strategy and a management strategy for springs that could be affected by falls in water levels. The federal approval conditions strengthen these arrangements for springs that are nationally protected. Santos, QGC and Australia Pacific LNG have developed a joint industry plan to coordinate their approach to protecting springs.  This acts as a framework for a groundwater monitoring and management system. It includes the location of monitoring bores, aquifers to be monitored, monitoring frequencies, a method for analysing results, drawdown triggers and response actions. The companies will also monitor potential impacts to groundwater.

Under the joint plan there are strict limits on what can happen before intervention is called for:

  • the investigation trigger value is set at 50 per cent of the drawdown limit
  • the management/mitigation trigger is set at 80 per cent of the drawdown limit
  • drawdown limits are set to a level that would correspond to zero drawdown at the spring.

This plan allows companies to detect and mitigate impacts to springs early. This means that mitigation measures such as reinjecting water into the springs source aquifer, providing flows at the springs, or the retirement of existing bores and substituting with bores into a different aquifer, can be swiftly put in place. This monitoring and mitigation approach is set out in Figure 2 below.

An example of an adaptive management approach drawn from the Joint Industry Plan for springs monitoring and management

Figure 2 - An example of an adaptive management approach drawn from the Joint Industry Plan for springs monitoring and management.

Santos’ water monitoring and management plan was approved November 2013.