Still chewing fat on spill bill
Eight months after a 60-tonne fat spill blocked part of New Plymouth’s sewerage system, less than half the $541,000 clean up cost has been paid back.
Last September, about 60 tonnes of tallow, a substance made from rendered animal fat which is used in pastries, margarines and biofuels, ended up in the district’s sewerage system.
This spill happened at GrainCorp Liquid Terminals on Port Taranaki land in New Plymouth.
The fat – enough to fill just over two 20ft shipping containers – set fast in a sewerage system pump station and left hundreds of residents unable to flush their toilets for several hours while it was cleaned out.
New Plymouth District Council took charge of the cleanup, which required the fat to be melted with hot water so it could be pumped out and trucked to the city’s Colson Rd landfill.
The work cost $541,000, of which the council had so far recovered $246,925 from GrainCorp.
Discussions were continuing to recover further costs, relating to landfill charges and internal staff time, NPDC risk management lead Rowan Betts told councillors at Tuesday’s committee meeting.
Should those discussions not reach the desired outcome, Mayor Neil Holdom asked if they could go to GrainCorp’s landlord – Port Taranaki, owned by the Taranaki Regional Council.
Infrastructure manager David Langford said that was a possibility, through the trade waste bylaw.
‘‘Both parties have some degree of liability,’’ he said.
‘‘The port are the holders of the trade waste consent with NPDC that allows them to discharge from their network into our network.’’
But they were making progress with the negotiations with Graincorp, he said.
‘‘I imagine we will meet a mutually acceptable outcome.’’
Investigation into the incident showed a discharge of hot tallow had entered the trade waste system, due to the interceptor (a mechanism to control flow) from the tallow site being left open, a report to Taranaki Regional Council noted earlier this year.
‘‘The liquid tallow had solidified in the sewerage system, resulting in the blockage of the pumps at the pump station and subsequent sewage discharge.
‘‘Investigation found that there was a white/yellow substance on Ngamotu Beach near the Hongi Hongi Stream approximately 30 metres long, and there was also a slight sewage odour near the Hongi Hongi Stream outfall.’’
The company explained that the fat had been discharged from a sight glass (a transparent area in a tank to see inside) on a storage tank.
In a statement yesterday Graincorp said its insurers were working with the New Plymouth District Council.