An investigation into the Refining NZ oil pipeline leak in Northland which caused flight disruptions and a serious fuel shortage in Auckland has found it cannot prosecute anyone over the incident.
The Northland Regional Council says while the 124 cubic metre spill last September was a breach of the Resource Management Act, they don't have a prosecution case for anyone involved.
The investigation found an unknown digger searching for swamp kauri may have triggered the pipeline leak.
However because the precise date and time of the damage are unclear, the leak could have happened at anytime.
The Northland Regional Council says while the discharge itself was a breach of the Resource Management Act, the council "does not have a case for prosecution of any party".