Santos’ coal seam gas operations in northern NSW are being investigated for a leak at one of the company’s wastewater ponds.
The NSW Environment Protection Authority (EPA) told Fairfax Media it is examining an apparent leak from the company's Tintsfield pond, near Narrabri.
“The extent of the leak has been the focus of our investigations," an EPA spokeswoman said. "However, preliminary data suggests that there is no risk to the environment."
The possible leak was identified by an anti-CSG activist group, Lock the Gate, which uncovered the investigation from documents released under freedom of information rules.
In March, Santos was fined $1500 when another of its wastewater ponds at nearby Bibblewindi in the company's $1 billion Narrabri Gas Project was found to be leaking.
The “pollution incident” contaminated an aquifer below the pond, with water identified to contain uranium levels at about 20 times safe-drinking standards. Santos has stressed the aquifer was not used for household or livestock use.
The campaign co-ordinator for Lock the Gate, Carmel Flint, said the latest investigation underscores the risks associated with the storage of CSG wastewater, and called for “full disclosure on this case as a matter of urgency”.
“The Tintsfield wastewater ponds are on productive farmland within eight kilometres of the edge of the township of Narrabri,” Ms Flint said.
“When Santos was fined over the Pilliga leak, the investigation found that the dam liners were of poor quality and there is every reason to be concerned that the same problem has occurred at Tintsfield.”
The EPA spokeswoman said the authority was "hoping to finalise its report shortly”.
A Santos spokesman said the company had reported the findings in May 2013, and the firm was working with the EPA to monitor the water.
“Water-monitoring bores have identified elevated salinity and naturally occurring heavy metals - as is typical for the surrounding soil - underneath two water storage ponds on Santos-owned land, adjacent to the Wilga Park Power Station,” Santos said in a statement.
“The source of the water detected by the monitoring bores remains unclear; however, it is likely that some of the water detected is due to previous integrity issues associated with the lining of Tintsfield Pond 1,” the company said.
The company also downplayed any risk from leak to local water supplies.
“The water immediately underneath the ponds remains isolated and is not connected to any useable aquifer,” the statement said.
“This water is not used - nor is it viable to be used - for agriculture, stock irrigation, human consumption or domestic purposes and there is no risk to people or livestock.”
Santos and the EPA said neither of the Tintsfield ponds had received relocated wastewater from Bibblewindi for more than a year.
The story Suspected leak at Santos CSG project under investigation first appeared on The Sydney Morning Herald.