Modifications to water temperature caused by the release of hypolimnetic water from thermally stratified reservoirs pose a major threat to the aquatic biota of lowland rivers in Australia's Murray-Darling basin. Keepit Dam is earmarked as one of several deep-release structures in the basin causing ecologically significant temperature modification over a large length of river. This study utilized discrete and continuously monitored historical water temperature data from stream gauging stations, together with reservoir thermal profile data, to assess the impacts of Keepit Dam on the thermal regime of the Namoi River. Modifications to selected components of the river's annual temperature cycle were quantified in relation to a pre-dam temperature regime estimated from statistical models incorporating catchment, hydrological and sample attributes. Keepit Dam has modified the thermal regime of the Namoi River. The effect was greatest immediately downstream from the dam where the annual maximum daily temperature was approximately 5.0°C lower and occurred three weeks later than the pre-dam condition. This change was sufficient to disrupt thermal spawning cues for selected Australian native fish species. The magnitude of disturbance progressively diminished with distance from the dam. Key aspects of the river's annual temperature cycle were largely restored to the pre-dam condition within 100 river km downstream from the dam, which is closer than previous estimates. However, there was marked inter-annual variation in the magnitude of thermal modification and ecological impact as a result of year to year changes in tributary flow and reservoir behaviour.

The conservation biology of Australasian freshwater mussels is hindered by While the need for a taxonomic revision is paramount, progress in conservation may 33 depend also upon involving the wider community.

Fundamental science and engineering research at Monash University and The University of Melbourne in Australia has enabled the alumina industry worldwide to reduce the volume of waste produced by about fifty percent. Valuable raw materials are recovered, and the risk of storage failure is eliminated. Across the mining industry, there are at least two major storage failures annually worldwide, resulting in deaths and environmental disasters. The failure in Hungary of a storage facility for bauxite residue in October 2011 resulted in eight deaths and a fine of 472 million euro ($US648 million) and the arrest of the CEO (later released). The new technique called dry disposal produces a paste for stacking and drying instead of a water-like suspension to be stored in a dam or pond. Simply removing water from the suspension and reusing and recycling water represents a step toward a more sustainable practice in the industry. As the concentration of such a suspension is increased as a result of dewatering, the materials exhibit non-Newtonian behavior, characterized by shear thinning, a yield stress, and in some instances, thixotropic behavior. Such high concentration, nonideal (dirty) suspensions in the resource industries has meant that new rheological methods and techniques were needed for both shear and compression rheology to measure and interpret the basic flow properties. Also, some older empirical techniques needed to be modified and interpreted in a more fundamental way so that the results could be used in design. The paper reviews these techniques and illustrates how the industry itself has motivated their development. Understanding and exploiting this rheology has resulted in dramatic improvement in the waste disposal strategy for some industries, but many have failed to embrace the available technology. Why? Is regulation the answer? Probably not. The paper concludes that a greater positive change in the waste management practice will occur in the future, motivated by a number of factors, including public perception, water recovery, the necessity to earn the right to operate, and perhaps even by common sense accounting. The paper is a review of thirty years of work with the resource industries on environmental waste minimization. Aspects have been published in the Proceedings of Paste and Thickened Tailings Conferences held annually since 1999 (Jewell, R. J., Fourie, A. B., Eds.; Paste and Thickened Tailings–A Guide, Second ed.; Australian Centre for Geomechanics: Perth, 2006), in Chemical Engineering Science (Boger, D. V. Chem. Eng. Sci. 2009, 64, 4525), and in the Proceedings of the Second International Future Mining Conference in 2011 (Jones, H.; Boger, D. V. Proceedings of the Second International Future Mining Conference 2011, Sydney, 22–23 November, 2011).

No abstract