- Peter Sif
- Accident date
- Accident area
- west of Ushant island
- Spill area
- Cause of spill
- Quantity transported
- 43 tonnes of diesel oil and 350 tonnes of bunker fuel oil
- Nature of pollutant
- diesel oil and bunker fuel oil
- Ship / structure type
- Built date
- 98.96 m
- 16.01 m
On 15 November 1979, the Peter Sif sank in Lampaul Bay off Ushant Island (Brittany). The bunkers contained 350 tonnes of fuel oil and 43 tonnes of diesel. The bunker fuel presented an immediate pollution threat for the environment. The wreck lies at a depth of 57 metres on a sandy seabed.
After the shipwrecking, the ship’s insurers were given formal notice to take all the necessary measures to stop the leaks reported by the French navy divers. Work was carried out to completely plug the leaks.
On 16 February 1980, the insurers decided to abandon the ship and deposited their limit of liability. Thereafter, it became the French State’s responsibility to respond to the threat posed by the wreck if deemed necessary. For several years, the wreck was regularly monitored by French navy divers on behalf of the State.
In October 1981, a report showed that pumping the remaining fuel out of the bunkers was technically possible but too costly. Blasting the wreck was also feasible, but the risks of polluting the bay were too high, even if all possible precautions were taken.
From September 1998, the wreck began to give signs of deterioration: several small leaks (1 to 5 litres/hour) had to be plugged during the winter and spring. In order to prepare for future operations, the wreck was studied closely, the relevant bunkers identified, currents measured and anchoring points positioned.
On 7 June, taking advantage of the clement weather, the Préfecture Maritime set men and machines in motion to parry the threat.
An action plan was drafted as follows: a floating cylindrical boom was to be moored above the wreck and fuel tanks opened one by one. The propulsion fuel would then to float to the surface and be contained by the boom, before being pumped out of the boom by a high capacity skimmer. The following factors contributed to the protection of the environment:
- clement weather conditions (the mild north easterly wind and no swell)
- divers were standing by to blank off the fuel tanks
- the floating boom was oil-tight (reinforced by additional sorbent boom)
- men and equipment were made ready at sea and ashore in order to clean up the oil should it slip under or over the boom.
130,000 litres of fuel oil were recovered in total and it became apparent that the estimates provided by the response team when the vessel sank may have been somewhat inaccurate. One tank which was said to contain 102,000 litres was found to be rusty and full of seawater, which pointed to the fact that the oil had left the tank quite some time ago.
In 1999, this emergency operation emptied large tanks where fuel remained in the wreck of the Peter Sif and thus saved the shores of Ushant Island from the threat of heavy pollution. As time went by and as corrosion started to set in, occasional upwellings of oil from the wreck remained possible, as some oil was no doubt trapped in some remote sections of the vessel.
Despite all these efforts, in October 1999, heavy sheen was observed on a daily basis off the coast of Ushand Island. In October 2003, extensive sheen was reported once again, this time by a fisherman. In November 2005, a breach was clearly identified by divers. Then in December 2005, the wreck began to leak more regularly and a small operation was carried out.
The Préfecture maritime, the mayor of Ushant Island and the response coordinator decided on an operation program to recover the 160 tonnes of oil remaining in the ballast tanks. A controlled operation to free the pollutant was to be carried out with surface recovery.
In early May 2006, the delicate pumping and waste recovery operations began. The Argonaute, an oil spill response vessel chartered by the French navy, was used to position buoys which would be used to deploy a floating boom. The other necessary technical installations for the pumping operation were also set up. The operation lasted about twelve days, before the weather conditions deteriorated and forced responders to call a halt to operations.
From 20 to 27 June, a second team of divers finished off the operation. In total, 11 tonnes of oil (14 m³) were pumped out of the wreck.
Before leaving the site, the divers installed 2 polyurethane socks with a capacity of 700 litres, each positioned at an opening in the hull to recover any fuel oil which may move towards the surface. A first operation to change these socks and recover the trapped oil was successfully carried out in March 2007.