Open Cut » Environment
A significant area of risk associated with mine closure is the question of completion criteria for native ecosystem rehabilitation ? will the regulators and the broader community accept defined standards as part of an overall mine closure plan, and agree to lease relinquishment? Both regulators and mining companies are addressing this issue across the country, but there are relatively few examples of mine closure strategies that have been through a full public review process and then been signed off by both the mining company and all regulatory authorities.
The objective of this project was to develop an agreed, workable process for addressing relevant issues relating to mine closure and associated completion criteria when establishing native vegetation communities following coal mining in the Hunter Valley of New South Wales. It follows a similar ACARP Project (C12045) conducted in Queensland's Bowen Basin. Both projects were intended to reduce the uncertainty relating to completion criteria for native ecosystem establishment.
Work was carried out in two stages. Stage 1, which commenced on 1 March 2004, involved reviewing workable processes that have been developed in conjunction with regulators. Discussions took place with staff at the New South Wales Department of Mineral Resources, Queensland's EPA, the Western Australian Department of Industry and Resources and mining companies in NSW, Queensland and WA to exchange views on processes for developing completion criteria.
Site visits were held concurrently with the above reviews. These involved visiting more than eleven coal mines in and near the Hunter Valley, and included all major mines attempting to establish native ecosystems following mining. At each site, discussions with the environmental officer took place, followed by an inspection of rehabilitation and surrounding unmined sites, and a review of relevant company reports.
Following Stage 1, a meeting involving mining industry attendees was held in July 2004 to review progress and plan the work program for Stage 2. Participants selected Xstrata's Westside mine and the Camberwell Coal mine to be used as case studies to demonstrate how a process for developing completion criteria might work in practice. At the same time, a general approach to addressing issues relating to completion criteria was developed. This approach includes the selection of specific rehabilitation objectives, design of monitoring programs (including key aspects such as what indicators, parameters and reference sites could be used), suggested techniques for demonstrating sustainability, selection of completion criteria (or at least a process for developing them, in the case of specific ecological targets) and addressing the needs for post-relinquishment management and monitoring.
The findings were synthesised into a set of principles that mines can use in designing monitoring programs and in the selection of rehabilitation completion criteria, reference sites, and key performance indicators. The principles are designed to assist companies in meeting regulatory authorities' expectations for obtaining a Development Consent, and subsequently fulfilling these requirements. A presentation and draft report outlining the project's findings and recommendations was reviewed by industry participants at a second meeting held in Singleton in December 2004.
This report explains the process undertaken, and outlines the reviews carried out, the process and guiding principles developed, and the two case studies used to illustrate how they might work in practice.