Discharges during bunkering and internal trasfer of fuel

The amounts per spill may be small, but in a port area or on a beach, even small spills can cause significant damage. Discharges of oil, diesel and substances harm nature and will affect algae, plants, fish, birds and animals.

What has happened?

A selection of reported incidents:

• During the internal transfer of diesel, a tank was overfilled, and an estimated 50 litres of diesel went into the sea.
  
  
• During the filling of diesel, the pressure was too high. This resulted in diesel coming out of the vent, with an estimated amount to the sea of 20–30 litres.
  
  
• After bunkering, there was some spillage on deck, which was thought to be under control. It turned out that some diesel had come out of the vent on the boat deck. There is no measurement of the a mount that was discharged into the sea, but an estimate is 20–50 litres.
  
  
• During the filling of the day tank on the flushing barge, it was overfilled with about 50 litres of diesel.
  
  
• Overfilling of 300 litres of diesel during bunkering of a cargo ship, absorbents have been deployed, and the fire department is on the way. The police and the Intermunicipal Committee Against Acute Pollution (IUA) have been informed about the incident.
  
  
• During the internal transfer of diesel on boards, there was an overfill, and approximately 20–40 litres went into the sea.
  
  
• The vessel overfilled at the quay, with an estimated 100–150 litres going into the sea. The bunkering was done from a tank truck. The Norwegian Coastal Administration was notified and the fire department was on its way.
  
  
• While conducting a ROV operation and filling the day tank, approximately 50 litres went into the sea due to human error.
  
  
• During the filling of diesel at the port, the fuel tank was overfilled, and fuel came up and out of the vent. When the hose was disconnected to end the filling, there was vacuum in the fuel tank, causing more fuel to spray out of the tank. It is estimated that around 30 litres went into the sea.
  
  
• Due to a possible fault in the diesl tank's gauging system, too much biodiesel was bunkered (completely full tank). This caused diesel to come out of the vent pipe on the deck after the vessel when the vessel started moving after leaving the quay. It is estimated that approximately 15 litres of biodiesel went into the sea through the drain pipes on deck.
  
  
• It is reported that during the trasfer of diesel to the day tank, diesel went onto the deck and into the sea. The peliminary estimate is up to 1,000 litres. The port and local fire department have been informed and are present.

The list does not include all recorded spills in 2024, but it illustrates the extent. There have also been reports of new spills in 2025.

Why do we have spills?

Each spill has its causes. It can be due to errors in reading the tank level, lack of monitoring during filling/transfer, technical faults with the level gauge, built-up pressure in the tank, hose breakage or other reasons.

All vessels should have their own bunkering procedures to ensure no spills occur. There should also be a plan for what to do if something goes wrong and in case of a risk of spills into the sea.

Onboard measures will be to limit and handle any spills with SOPEP* (Shipboard Oil Pollution Emergency Plan) equipment. If the vessel is at the quay or in a port, it will also be possible to get help from the port authority and the municipality. Always remember to report spills to the authorities.

Advice

If you have good procedures and established good routines on board and follow them, things will mostly go well. The list below is not exhaustive:

Before, during and when bunkering or transferring oil or diesel:

• Ensure that the equipment is intact, including connections and pipes, etc.
• Check how much space is in the tank/system, and if it needs to be completely filled
• Continuously monitor the bunkering and transfer process
• Keep an eye on the tank level before and during filling
• Have good stop procedures and emergency stop for filling
• Know where the SOPEP equipment is located and how to use it
• Make sure contact information for external help is easily available in case of an accident
• Maintain good communication with those on board and external parties at the tank facility, truck or boat

*SOPEP (Shipboard Oil Pollution Emergency Plan):
Emergency plan for oil pollution, MARPOL, Annex I, Regulation 37: Oil tankers of 150 gross tonnage and above, and all ships other than oil tankers of 400 gross tonnage and above, must carry an approved Shipboard Oil Pollution Emergency Plan.