MORE than 500 derelict mines remain across the state, leaving a legacy of many thousands of hectares of degraded or contaminated land.
In his latest report, NSW Auditor-General Peter Achterstraat warned derelict mines might represent the state’s largest category of contamination liability.
His audit, of agencies focused on environment, water and regional infrastructure, which was released last week, noted 27 of the former mine sites had been cleaned up during 2011-12 at a cost of $2.1million under the government’s derelict mines program.
But 573 sites remained across the state, as of the end of June.
‘‘The derelict mines program has many thousands of hectares of degraded and contaminated land where mining companies abandoned mines without cleaning up or stabilising sites,’’ Mr Achterstraat said.
On Saturday the Newcastle Herald reported a Gillieston Heights couple faced financial ruin after unknowingly building their home above an old mine. The four-bedroom brick home of Andrew and Kylie Neale had shifted and cracked, and sink holes up to four metres wide had appeared on their property.
Last month, Resources minister Chris Hartcher announced a new advisory council would oversee the rehabilitation of former mines and look at best practice.
A new industry levy is expected to raise about $13.1 million, some of which will be spent on rehabilitation work.
Mr Achterstraat’s report also looked at the State Property Authority and noted a funding shortfall of $28.1million for remediation of former BHP land at Mayfield and Kooragang Island that the authority assumed liability for.
The shortfall was due to increased costs, he said.