Uranium miner ERA has escaped prosecution following an incident on December 7, 2013 when about 1,400 cubic metres of acidic slurry spilled after a leech tank collapsed at its Ranger site in the Northern Territory.
The spill was contained within the mine site, a statement from the NT Department of Mines and Energy said.
Department staff inspected the site the day of the incident and assessed the response by ERA.
The incident was also investigated by the Australian Government’s Supervising Scientist, NT Worksafe and an independent investigation for the Northern Territory and Australian governments.
The Supervising Scientist’s investigation report concluded that the spill did not result in any adverse impact to the offsite environment or any impact to the health of local residents or mine workers. This report was based on extensive surface, groundwater and radiological analysis.
The department said it had completed a thorough investigation into the incident.
Based on legal advice, the department has decided that it is not in the public interest to prosecute ERA under the Mining Management Act. A statement of reasons has been released.
It said quarterly audit reports over the past year had indicated ERA was making significant progress in implementing a process safety program and using process safety to define risk and controls to reduce the risk of a similar incident occurring again.