Dumping oil in New Zealand waters has cost a Korean company $37,000.
Juahn, a "small" company chartered by Sanford Ltd to help catch its fishing quota, was convicted after pleading guilty on two charges of discharging a harmful substance into New Zealand seas.
The case was heard by Judge Joanna Maze yesterday in the Timaru District Court.
Juahn was found to have broken the rules after it dumped oil at sea instead of putting it through an "oily water separator" once the ship returned to port.
The incident happened on January 14 after the chief engineer suggested a pump be used to discharge directly overboard.
Defence lawyer Anna Kraack said there was no way of knowing how much had been dumped, but she understood it was at the lower end of the scale.
"If it was a large quantity of oil we would have expected to have seen some sign of that in the environment."
She said the engineer did not tell the master or Juahn the practice was occurring.
"It was a rogue employee," she said.
"There's no understanding of the motive of the chief engineer, why he decided to direct this.
"Juahn, it is safe to say, was shocked when it found out this was occurring."
The chief engineer has been dismissed. Juahn has since put prevention measures in place to ensure such an event did not happen again, Ms Kraack said.
Judge Maze took into account the defence believed the amount discharged was not a significant amount and the company was remorseful for its chief engineer's actions.
"It was a single event, on a single day.
"It is relevant that the owner had processes in place to avoid this, but they were over-ridden, in effect, by its own employee."
She fined the company $37,000.
- The Timaru Herald