Mine site rehabilitation conditions in Western Australia

Rehabilitating land following mining is a major and growing issue for Western Australia (WA), with around 2.5 Mha of land currently under an active mining lease. About 85% of mining project proposals assessed by the WA Environmental Protection Authority (EPA) have had rehabilitation and/or closure conditions recommended and subsequently applied by the Minister for Environment through a ministerial statement. This is in addition to the requirements for rehabilitation and/or closure specified under the Mining Act 1978 (Government of Western Australia 1978). This project collected and analysed publicly available information on mine rehabilitation conditions in WA to provide baseline information for the state. Closure conditions required by the EPA were assessed for 277 ministerial statements dating back to 1987. Until the 1990s, conditions related to rehabilitation have primarily been assigned to the decommissioning phase, with progressive rehabilitation requirements starting to appear from 1992 onwards. Despite the importance for assessing completion, just over 31% of the projects specified rehabilitation targets to be met. These rehabilitation targets focussed most often on the percentage of vegetation cover and species diversity. We further aimed to quantify the costs of rehabilitation works as part of assessing the achievability of recommended rehabilitation and/or closure conditions. However, obtaining cost data, evidence of rehabilitation progress, or evidence on rehabilitation success in publicly available documents proved challenging, with very limited amount of information available. The post-mining land use proposed at a site was not always specified and could often not be found for projects pre-2013. Current lack of transparency points at the need for knowledge sharing and/or a data repository where proponents, regulators, and researchers can jointly work towards achievable and acceptable mine rehabilitation.