IN an effort to avoid prosecution for a caustic soda leak into waterway, Lithgow City Council is hoping to sign a legally binding agreement with the NSW Environment Protection Authority (EPA).
The leak, which occurred in October 2019, was caused by the failure of a caustic soda tank at the Wallerawang Sewage Treatment Plant (STP).
The leak went into an unnamed waterway that runs across a private property and also council-owned land adjacent to the STP.
Council was issued a remediation notice to clean up the affected area, with the EPA having oversight over the works.
Mayor Ray Thompson said council was advised of the EPA's intention to investigate the matter for possible breaches of the Protection of Environment Operations Act 1997 on October 30, 2019.
"Council has fully complied with the requirements of the NSW EPA, with formal interviews of staff being conducted recently," he said.
The EPA has since advised there are sufficient grounds to proceed to prosecution for a range of offences.
Cr Thompson said rather then prosecution, council hopes to enter an enforceable undertaking, which is a legally binding agreement with the EPA.
"The benefit of enforceable undertakings is that they are an efficient, flexible and transparent tool," he said.
"They allow the EPA to obtain a set of fit-for-purpose commitments that address specific issues in response to an alleged breach.
"Enforceable undertakings are a more serious regulatory response than issuing a penalty notice but less serious than prosecution."
Council's water and waste water manager Daniel Buckens said that as part of the undertaking council had proposed a range of measures to ensure this does not occur again.
"This hasn't stopped us from taking action now, so we have acquired a range of additional positions, and we are currently in the process of reviewing all operational procedures including standard operation manuals," he said.
"We are also checking the workers executed drawings because there were incorrect locations of pipe work which affected the plant.
"We are also reviewing our pollution incident report plan and have been taking a range of actions from the time it occurred until now and it will continue regardless if we go into an enforceable undertaking or not."
Cr Wayne McAndrew said that he believed the caustic soda tank met government specifications and had been checked correctly.
Mr Buckens said it was a public works design from 2012/13 and it met the standards at the time.
"It was checked by public works, a contractor and council, but the issue is that it this particular design has a common occurrence of failure now," he said.
Mr Buckens said council had eight tanks of a similar design, and two had experienced failure so far.
"Environment wasn't a factor, it was a sequence of events, including the bunding stacks they sit within which was signed off as being water tight and free from leaks but leaked in the spillage," he said.