Derelict mines' impacts into Sydney's drinking water catchments

![CDATA[A large proportion of the residents in the state of New South Wales in Australia rely on the water supply catchments managed by the Sydney Catchment Authority (SCA). Established in 1998, the SCA is responsible for protecting and managing Sydney’s water supply catchments covering an area of 16,000 km2. It also provides bulk water to a large proportion of 4.5 million Greater Sydney residents. There are over 100 derelict mines located within the drinking water catchments managed by the SCA. While the majority of these do not pose a significant risk to water quality and/or environment, there are a number of derelict mines within the catchment that may pose significant water quality and/or environmental risk and, therefore, deserve further attention (necessitating development and implementation of appropriate rehabilitation plans). This paper presents the outcome of an investigation into selected derelict mines within the SCA-managed Sydney’s Drinking Water Catchments (DWCs). The focus is on the mines identified as posing a significant risk to water quality and/or environment. Likely hazards at each of the mines and potential impacts of these hazards on catchment water quality are presented. The outcome is a ranking of derelict mine sites, with the principal view of developing and implementing appropriate rehabilitation strategies. A brief review on derelict mine risk assessment and prioritisation process used in the study is also presented.]]