Independent testing completed on mine water discharges from West Cliff Mine
Media release: 7 September 2012
The NSW Environment Protection Authority (EPA) has received the results from independent water sample testing undertaken at four sites along the Brennans Creek and the Georges River.
Barry Buffier, EPA Chair and CEO, said the intent of the testing program was to help validate the information previously provided by BHP Billiton under recent Pollution Reduction Programs and to inform future strategies to manage the discharge waters.
“This latest round of testing was conducted over a six week period in May and June 2012 and measured the toxicity and chemical characteristics of mine water discharged from West Cliff mine to Brennans Creek and the Georges River.
“An extensive chemical analysis of the discharge, upstream & downstream waters was carried out, including a wide range of metals and salinity.
“The impact of the discharge on a suite of sensitive organisms, including fish, macro-invertebrates and micro-organisms was studied. The results show the discharge is affecting some sensitive aquatic life, but not all organisms. The detected eco-toxic effects were primarily limited to acute lethality effects on larval fish and reproductive impairment in water fleas,” Mr Buffier said.
Mr Buffier said the report, Chemical and Ecotoxicology Assessment of the Discharge Waters from the West Cliff Mines, highlights the complex nature of the discharge and the interplay of various factors that may give rise to the observed effects.
“For example the report found trace metals and bicarbonate may be contributors to this toxicity but the relative contribution of these factors is not currently clear. Bicarbonate appears to be a contributor to the observed effects and this is a new area that requires further consideration.
The Report, which was received by the EPA at the end of August, recommends further independent chemical modelling be carried out on the current data to better interpret the ecotoxic effects.
The EPA is reviewing its findings.
Mr Buffier said the information, together with the latest reports from West Cliff will help inform new licence requirements with respect to mine water discharges into Brennans Creek.
“We are aiming to have enforceable limit conditions on the licence by the end of October 2012,” Mr Buffier said.
“The EPA intends to invite public submissions on these proposed limits before they are placed on the licence.
“Once the licence limits have been established West Cliff will be required to implement them immediately and monitor results closely.”
The EPA is continuing to review the Office of Environment and Heritage (OEH) report, which is publicly available on the OEH website at - http://www.environment.nsw.gov.au/air/coalminingNSW.htm
Contact: Liza Cassidy
Page last updated: 14 September 2012