First it was Wambo mine now a dam has failed at Warkworth and Bengalla open cut mines.

Heavy rain is being blamed for two new dams spill at coal mines in the Hunter Valley.

NSW Environment Protection Authority (EPA) is investigating the collapse of part of a sedimentation dam wall at Rio Tinto’s Warkworth coal mine and further up the valley at the company’s Bengalla mine a dam overflowed following heavy rain last Thursday night and throughout Friday.

Photograph supplied by John Krey

Photograph supplied by John Krey

This comes on top of a dam failure at the neighbouring Wambo Mine where a wall collapsed releasing sediment laden water into the environment.

At Warkworth personnel contacted the EPA regarding the partial collapse of the wall on January 6. At that time, the company indicated that the event had not caused or threatened material harm to the environment. Nonetheless, the EPA requested an incident report.

The company also advised the EPA that it had undertaken work to contain the sediment laden water. However, photographs provided to the EPA on 15 January suggest that sediment laden water – made up of soil and sand is continuing to leave the site, and a quantity of sediment from the original incident is yet to be cleaned up. 

The EPA has requested additional information from Warkworth and will be conducting a site inspection to assess the impact. Depending on the outcome of the investigation, the EPA will consider further regulatory action.

A spokesman for Rio Tinto operators of the Warkworth mine said “A partial failure occurred in a sediment dam at the Mount Thorley Warkworth site during the heavy rainfall experienced across the Hunter Valley last week, with falls in excess of 100 millimetres recorded in the Singleton area.

“We voluntarily reported the incident on the same day to the Environmental Protection Authority as well as the Singleton Council, which sent an engineer to inspect the site and confirm there was no risk to motorists.

“The dam contained runoff water from pre-mining activities, and flowed through culverts under Wallaby Scrub Road on to Coal & Allied owned farm land.  The dam was drained and deepened to prevent further flow of water.

“As part of ongoing and regular monitoring of the area, we inspected the dam on Friday following rainfall to confirm that no water is leaving the dam.

“The incident is being fully investigated in cooperation with the Environmental Protection Authority.”

The company reported after heavy rain on Thursday and Friday last week, Bengalla Mine voluntarily contacted the EPA on Friday to advise that water from the mine water system had overflowed.

Bengalla is working with the EPA to investigate the incident, a Rio Tinto spokesman said.

“As the coal industry heads for the exit door, they are cutting costs and trashing the environment almost with impunity,” said Greens MP Jeremy Buckingham.

“Three coal mine dam failures in the Hunter, in addition to two major spills at other coal mines in the last six months indicates there is a systemic problem with the environmental standards being applied by the industry.

“Premier Baird needs to wake up and stop ignoring the reality that coal is in terminal decline, and his government needs to act to protect the environment and the community.

“Where is the strategy that recognises the direction of the energy market is away from fossil fuels and into renewable energy?  Where is the transition plan to assist workers and to provide an alternative basis regional economies?  Where is the plan to ensure these companies rehabilitate the landscape to an adequate standard and protect the environment?

“Without strong regulations and independent monitoring to prevent pollution incidents, the decline of the coal industry represents a toxic threat to the environment and community.”