Oil spill incident

A member has reported an incident in which a bunker hose parted and a 40 litre diesel oil spillage occurred onto the deck and into the water. The incident occurred during transfer of fuel to a shore-side road tanker. When the fuel transfer pump started, initially at low pressure, a knocking sound was heard followed by the bunker hose disconnecting and parting from the bunker manifold. Some 2 litres of diesel oil was sprayed into the sea owing to the wind, whilst the majority of the spill was contained on the vessel’s main deck. The Chief Engineer, who was on deck, gave the order by VHF to stop the fuel transfer pump immediately and at the same time he reported to Duty Officer on the bridge. The pump was stopped and Chief Engineer on deck with duty crew secured the hose on the vessel deck to avoid the diesel oil spraying in to the water and to minimize environmental pollution.

Emergency procedures were followed and the spill was cleaned up according to the Shipboard Marine Pollution Emergency Plan (SOPEP). The diesel oil spilled on the vessel deck was contained; patches of light sheen were observed on the sea water surrounding the vessel as a result of the small amount of diesel oil spraying from the hose. No injuries were reported; slight environmental pollution resulted from this incident.

Our member’s investigation revealed the following:

  • All personnel involved, including the Master, Chief Officer, Chief Engineer and 2nd engineer were properly certified and qualified and extensively experienced with this vessel and the nature of operation;
  • There was a risk assessment in place for bunkering and transfer of diesel fuel, as well as an environmental aspect impact register, outlining the possible risks involved in this operation, and listing the proper control measures. During interviews with the vessel’s crew, it was evident that officers and ratings were familiar with these documents;
  • A checklist, toolbox talk, and job hazard analysis were found to have been completed for bunkering and transfer of diesel fuel;
  • Before starting delivery of diesel oil, the Chief Engineer had conducted a thorough physical inspection of the delivery line, including valves, hose and connections etc.;
  • Communication between all parties was satisfactory;
  • The Chief Engineer had obtained verbal confirmation from the shore truck operator that the valves were open and the truck was ready to receive bunkers. In spite of this, it is believed that the immediate cause of the incident was that the road tanker receiving valve was closed at the time the transfer pump was started and caused the sudden rise of pressure in the bunker hose which resulted in the hose connection failure.

The following lessons were learnt:

  • Due to the nature of such operations, additional effort should be undertaken to ensure that the receiving party is ready ‘Valves open, communication effective, prepared for emergencies’, before starting the pump;
  • All connections in use should be appropriately certified, including hoses, reducers, camlock connections etc, with certificates available on site /vessel at all times;
  • All such connections should still be properly inspected before starting fuel transfer operations;
  • The temporary plugging of all deck openings during fuel transfer operations would prevent such damage to the environment in case any spill occurs;
  • Ensure remote stop for the fuel transfer pump on deck is operational and crew are familiar with how to use it.