Water management in the mining industry has over time evolved with systems designed and constructed to meet operational water supply demands and to manage surface water and groundwater impacts. Some changes have also been required to meet new legislation and/or company standards. Progress in this area includes the integration of mine water management in the mine planning stages of mining developments to identify additional considerations and for staging the construction of water management infrastructure throughout the life of the mine. This includes the need for adequate rehabilitation provisioning (Treasury, 2017) and considering if the infrastructure is required post-closure, and if so, include post-mine use requirements into the design.
With the introduction of new or revised mining legislation, such as Queensland’s Mineral and Energy Resources (Financial Provisioning) Act 2018, there now is a requirement to develop a Progressive Rehabilitation and Closure Plan comprising both rehabilitation planning and a schedule to specifically define the nature and timing of works leading to post-mining land use, stabilised voids and rehabilitated waste storage facilities. This will require mine planners and designers to provide sufficient details on the integration of water management infrastructure into rehabilitation plans to ensure the plans achieve the agreed post-mining land use, or allow for effective management of non-use management areas. When relevant, the mining proponent will also have to undertake consultation to develop a Public Interest Evaluation Report to get stakeholder approval for these non-use management areas. Plans are required to provide details on area of activity, rehabilitation milestones, completion and milestone criteria and achievable milestone dates.
Developing a Progressive Rehabilitation and Closure Plan presents an opportunity to review the mine water management at every stage of the mine life and critically assess integration, timing and design requirements. Hence an opportunity exists to further improve mine water management as a support to the progressive rehabilitation requirements as a minimum, and to enhance and not hinder the rehabilitation progress.