Bay of Plenty Regional Council is investigating a rosin spill in the Tauranga Harbour.
The spill happened on Saturday night after a hose split while a ship was bunkering crude tall oil or rosin at Mount Maunganui's tanker berth terminal.
Regional council pollution prevention team leader Stephen Mellor said thevessel Stolt Span was bunkering the product +- a liquid by-product of pine pulp manufacture - when a hose connecting the vessel to the terminal split.
Rosin was spilled over the ship's deck shortly before midnight, Mr Mellor said.
Most of the spill ended up on the deck of the vessel but some discharged over the side and into the water. The bunkering procedure was being monitored, so pumping was stopped within seconds.
Crew and bulk storage staff immediately began cleaning up the spill to prevent any further discharge into the harbour.
"Bulk storage estimate between 100 - 200 litres of the rosin was released, however most of this ended up on the vessel and was able to be contained," Mr Mellor said.
"The amount of rosin that reached the marine environment was minimal, and the effects on the environment were minor. Initial investigations indicate that the pipe work used is pressure-tested every six months, and it will be returned to the manufacturer for tests to try find out the cause of the split."
The rosin is readily bio-degradable but is very toxic for fish. All materials used during the cleanup were disposed of safely. Regional council staff checked for any remains of the spill in the area at daylight, and none was found.
"We take these incidents seriously. These hoses should be virtually failsafe and we need to know what went wrong," Mr Mellor said.