Bioremediation of acid mine lakes
Sunday, 10 January 2010
Depending on local mineralogy, pit lakes may form into acid mine lakes (AMLs), a phenomenon quite common in Australia. The Australian mining industry is facing major challenges in developing methods to remediate the adverse effects due of acid mine lakes. Though there are some chemical and biological based technologies available, none are fully developed for ready application. Bioremediation technologies are most attractive to industry because of the low implementation costs and their ability to develop ecologically sustainable recycling processes. Recent research in the Centre for Ecosystem Management has focussed on ways to remove acidity, sulphate and heavy metals from acid mine lakes to enable a self-sustaining and functioning aquatic ecosystem to establish. A series of Australian Coal Association Research Program (ACARP) funded projects from 2006-2010 has been researching sulphate reducing bacterial (SRB) based bioremediation for AML treatment on a North Queensland mine site using locally-available sewage sludge and garden waste. Research has explored the technology including aspects such as organic matter quality and quantity and the influence of environmental factors like wind mixing, cyclonic events and incoming acidity sources. A critical factor in the success of such treatments is the selection of the 'right' organic matter and then applying it at an optimum dose to initiate and then sustain the bioremediation process. The planned outcome of this research is for the expansion of this technology to the remediation of other acid mine lakes across Australia and internationally.