The Asia Miner

APR-JUN 2019

The ASIA Miner - Reporting Important Issues to Mining Companies in the Asia Pacific Region

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Page 22 of 71

the asia miner • volume 16 • issue 2 21 WASTE TO ENERGY Coal ash has been reported to be one of Australia's biggest waste issues, accounঞng for 18 per cent of the naঞon's enঞre waste stream. Every year, Australian coal-fired power staঞons generate approximately 12 million tonnes of ash from burning coal, which can be turned into beneficial secondary products, but isn't. Reports show that approximately 44 per cent of coal ash is saved from dumps, but only half of that is used for beneficial purposes. With coal ash containing high concentraঞons of heavy metals that could pollute surrounding areas – either by controlled releases by the power staঞons, emergency dam overflows in heavy rain, or through seepage into the soil – it has become a growing health and environmental concern not only to the environmental groups, but also locals who live nearby coal-powered staঞons. Most countries line ash dams with an impermeable membrane to prevent water leaching into groundwater and nearby waterways, except in Australia, which may imply that all of them are polluঞng the environment to some extent. The ABC has reported on "extensive water and sediment sampling" conducted by the Hunter Community Environment Centre around the Vales Point and Eraring power staঞons in New South Wales. According to the ABC, the tests "found levels of selenium, zinc, nickel, copper, aluminium, iron, manganese, cadmium and lead in most samples" at "above healthy environment guidelines set by the Australian and New Zealand Environment and Conservaঞon Council". The NSW EPA warns fishermen not to eat more than three servings of fish from the lake due to high levels of selenium. Eraring's owner Origin Energy said it "monitored polluঞon as per its environment licence and that a new approach to ash management had helped reduce the potenঞal for polluঞon to migrate offsite". There are those, however, who have recognised coal ash not as a by- Coal ash – one of Australia's biggest waste issues Coal ash is one of Australia's biggest waste issues product, but a valuable resource for the construcঞon industry that can be turned into concrete. The fine ash, known as fly ash, can act as a parঞal subsঞtute to cement, with added benefits. Worldwide studies have proven that fly ash makes concrete that is technically beer, reducing the amount of cement used in concrete. Yet, Australia is a laggard in repurposing fly ash into beneficial secondary products. With only 44 per cent of fly ash being saved from ash dumps – and only half of that recycled into other products – Australia's rate is one of the worst in the world, where the global ash reuse averages 53 per cent, with Japan leading the way on 97 per cent. Despite significant research, Australia has also failed to develop other reuse industries which are growing overseas, including uঞlising coal ash to make bricks, construcঞon blocks and lightweight aggregate. Many see the prevenঞon of turning coal ash in Australia into a beneficial commodity driven by the cement manufacturing industry. And perhaps there is some weight behind that accusaঞon? According to the ABC, "the Australian Compeঞঞon and Consumer Commission has invesঞgated the industry in Queensland, and in 2017 Cement Australia was fined AU$20 million for restricঞng fly ash supply". But Industry body Cement Concrete and Aggregates Australia (CCAA), says fly ash must meet exacঞng standards to be suitable for concrete, and 90 per cent of what is available is used. As with everything, there are two sides to one story. At ঞmes, however, for the benefit of communiঞes, the environment and development of pathways towards closing the loop, it pays for those two sides to move in unison towards thinking and working outside the predictable disposable culture.

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