Underground » Environment - Subsidence and Mine Water
THIS REPORT IS PROVIDED AS A SET, COMPRISING C8005, C9067 & C18015
Since March 1999, original research work has been carried out to study the impacts of underground coal mining on creeks, river valleys, gorges and clifflines.
Numerous longwall extractions have already been completed and many more longwalls are planned beneath creeks, river valleys, gorges and clifflines in the NSW Coalfields. Indeed, the very nature of the topography makes it virtually impossible to avoid such features. All of the current coal mining operations in the Southern Coalfield, and most of those that are planned in future, are taking place in areas of steep topography and are likely to have some impact on creeks, river valleys, gorges, clifflines and associated infrastructure.
The research work is being undertaken by a multi-disciplinary team of researchers and the various aspects of the work have been split broadly into four sections as follows:
Management of the project, literature search, state-of-the-art review, empirical study, development of empirical predictive techniques and preparation of the final report, incorporating the work of other researchers. (Waddington & Associates Pty Limited)
Surveys and monitoring of ground movements, geological investigations and hydrological studies, rock classification and testing and in situ stress measurements. (Carried out by BHP supported by external consultants, with data input from other collieries, the NSW Dams Safety Committee and Sydney Catchment Authority)
Numerical modelling and development of numerically based predictive methods. (CSIRO Petroleum)
Design and construction of a physical scaled model that can be used to illustrate the underlying mechanisms of strata movements for a range of different mining scenarios. (The School of Mining Engineering of the University of New South Wales)
The research work has been funded in two stages and this report describes the work completed in the first stage of the project, which was completed in August 2000.
The report includes a comprehensive state-of-the-art review and some initial findings that have arisen from the empirical studies, the numerical modelling work and the initial testing of the physical modelling facility. The research work is continuing and it is projected that these ongoing studies will provide new insights into the mechanisms involved as creeks, river valleys, gorges and clifflines are undermined.
The final output from the research project will be a set of management guidelines, to assist mining companies that are planning to mine in areas of steep topography in the future. The importance of ongoing research in this area can not be overemphasised, since future longwall approvals might well depend upon it.
An e-newsletter has also been published for this project, highlighting its significance for the industry.