A truck servicing company has been fined $19,500 for discharging oil into a drain leading to an important wetland and wildlife refuge.

The penalty follows the company, Truck Stops (NZ) Ltd, having already forked out nearly $10,000 to clean up the accidental oil spill, upstream of the ecologically significant Ahuriri Estuary in Napier.

It also spent $7500 to remove oil from its Napier yard and to fix valves, lines and a pump in a washdown bay.

The company, through its lawyer Richard Flinn, told the Napier District Court that the spill in December 2021 was due to a systems failure stemming from “accidental, one-off events”.

These were a wrongly positioned valve in a service pit, the failure of a waste pump, and significant rainfall which triggered the system to discharge into the stormwater network.

The company was prosecuted by the Hawke’s Bay Regional Council. It pleaded guilty to a single charge of discharging a contaminant under the Resource Management Act.

Judge Melinda Dickey said that on the morning of December 15, 2021, council staff discovered an oily sheen on the surface water of Plantation Drain at Ford Road in Napier, close to the Onekawa industrial area.

The contaminants had flowed out of the drain into Purimu Stream and on to the Ahuriri Estuary/Te Whanganui ā Orotū.

The estuary is designated a significant conservation area under the Regional Coastal Environment Plan, a wetland of ecological importance, and it includes a wildlife refuge.

Council pollution officers put hydrocarbon-sorbent booms in place and used a specialist vacuum truck to collect the oil.

Council officers contained the spill with a hydrocarbon-sorbent boom. Photo / Hawke's Bay Regional Council

They then traced the spill back to the Truck Stop yard on Ford Rd through the stormwater system, by lifting manholes on a number of industrial properties.

Judge Dickey said that since the spill, the company had upgraded its systems to prevent another accidental discharge of oil to the stormwater drain.

She said there was no evidence of long-term effects on flora or fauna.

Counsel Nicola Graham, prosecuting for the council, said the offence was careless.

All parties acknowledged the system’s failure was a combination of unfortunate events and was not foreseeable.

However, Graham told the court that it was incumbent on the company to ensure no waste left its site through the stormwater system.

Judge Dickey said: “I acknowledge that accidents can happen and can combine to cause a failure in a system that otherwise works well.

“However, it is important that there be systems and procedures in place to manage potential risk, and in this case to ensure that waste oil cannot leave the site,” she said.

“The steps since taken by the defendant will ensure there is no repeat of this incident, and I […] commend it for that.”

Trent Smith, national operations manager for Truck Stops, issued a statement apologising to the community and mana whenua.

“The immediate remedial work we undertook at the time, along with our fast response and full co-operation with the investigation, was acknowledged by the court,” he said.

“This was the first time we have had an incident of this nature. We have identified a range of opportunities for improving our systems and processes and we are committed to implementing these in full.”