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 Christos Bitas

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SpillsChristos Bitas

On 12 October 1978, the oil tanker the Christos Bitas was sailing from Rotterdam to Belfast, with a load of 35,000 tonnes of Iranian heavy crude oil, when she ran aground some 15 km off the Pembrokeshire coast. 4,000 tonnes of oil were spilled in the incident. The commanding officer managed to refloat the vessel without external help and decided to continue his journey, as he thought there was no longer any significant leak. He nevertheless warned the coastguards of the oil spill.

As the risks of environmental pollution were high, the owner of the ship (Adriatic Transports Ltd) and the owner of the cargo (British Petroleum (BP)) were immediately contacted by the coastguard. BP offered its services at once. It soon became obvious that the Christos Bitas was in fact seriously damaged and that she was still losing oil. Consequently, BP ordered the vessel to stop in order to avoid spreading the pollution.

Response operations were rapidly organised. Three distinct operations were simultaneously set up: the problem of dealing with the Christos Bitas, offshore response and onshore cleaning operations.


Dealing with the Christos Bitas

On 13 October, 2 tankers, the British Dragoon and the Esso York, sailed towards the Christos Bitas in order to lighter her. This operation lasted several days. By 20 October, 26,000 tonnes of oil had been removed from the Christos Bitas.

The question of the wreck of the Christos Bitas was then raised. The cost of repairing the vessel after cleaning and emptying the fuel tanks appeared excessive and the shipowner agreed to sink the vessel. This could however not be done in the Irish Sea because of the damage it would cause to the environment. The Christos Bitas was therefore towed in the Atlantic Ocean, to a very deep water area, 500 km west of Fastnet Rocks, where she would not interfere with navigation, fisheries or submarine telephone cables. She was scuttled on 31 October. An oil slick formed, but aerial observation showed that on 13 November it had dispersed naturally.


Lightering of the Christos Bitas by the British Dragoon (source: BP)


Offshore response

The foggy weather prevented aerial surveys from establishing the extent of the pollution. Nonetheless, all available personnel and equipment were sent to the grounding site. A fleet of 40 vessels rapidly gathered. They deployed booms to contain the oil and sprayed dispersants on it. They also used skimmers to recover the oil.


Dispersant spraying operations (source: BP)


On 16 October, the wind changed direction (from northwest to west) and strengthened. Aerial surveys were therefore made possible. They showed patches of oil near the islands of Skomer and Skokholm, which are nature reserves. In an attempt to stop oil from arriving on these islands, aerial spraying operations of dispersants were carried out. They considerably reduced the amount of oil. However they became less effective as the oil began to form an emulsion with the seawater.


Onshore cleaning operations

On 17 October, oil slicks began to arrive on the shores of Martin’s Haven and on the island of Skomer, both areas which were particularly fragile.

Martin’s Haven

Clean-up operations at Martin’s Haven lasted 4 days, from 17 to 20 October. Dispersant operations were largely ineffective on the mousse formed by water-in-oil emulsion. Therefore, manual techniques had to be used. About 35 tonnes of oil and oiled debris were removed using tractors, buckets and shovels. The cleaning operation ended with high pressure washing and dispersants.

Island of Skomer

This island is a nature reserve inhabited by a large number of seabirds and by 40 seals including newly-born calves. The use of dispersants in this environement was banned because of the rich ecosystem it represented.

Clean-up operations on the island started on 19 October. An estimated 350 tonnes of highly viscous mousse was on the beach. Access to the beach was quite difficult. Manual recovery operations were organised, however there were very few volunteers. Oil was confined using 3 booms and recovered by skimmers. However oil already treated by dispersants (aerial spraying) would not adhere to the belt skimmers. The decision was made to pump transfer the oil.

These operations recovered 300 tonnes of oil, 250 on the beach in 9 days and about 50 at sea from the booms in two and a half days. The manual operations had to be stopped on 28 October due to a lack of human resources.

On 25 October, small amounts of oil impacted the coasts of North Devon. Luckily, it was only slightly polluted and no cleaning operation was required. Action of the spring tides naturally removed the oil from rocks and beaches.


Localisation de l'île de Skomer

Localisation of the Island of Skomer (source : BP)


Name: Christos Bitas

Date: 12 October 1978

Location: Wales


Accident area: Pembrokeshire coastline

Cause of spill: grounding

Quantity transported: 35,000 tonnes

Type of pollutant: Iranian heavy crude oil

Quantity spilled: 5,000 tonnes

Ship type: oil tanker

Date built: 1963

Shipyard: Mitsubishi Nippon Heavy Industry, Yokohama

Length: 233.66 m

Width: 31.25 m

Draught: 16.08 m

Flag: Greek

Owner: Adriatic Transports Ltd




Impact on wild life

Out of the 40 seals living on Skomer island, 3 died from oiling. 1,520 birds were oiled, of which 1,035 died. The others were cleaned.

Species Total oiled Dead Alive birds
sent for cleaning
Guillemots 1030 660 370
Razorbills 346 319 27
Gannets 118 30 88
Puffins 7 7
Manx shearwaters 9 9
Common scoters 8 8
Black guillemots 1 1
Red-throated divers 1 1
What happened to oil birds ? (source: BP)



Oiled seal (source: BP)


Oil and debris disposal

After the coast had been cleaned, the problem was disposing of the oil and oiled debris. Refineries in Milford Haven agreed to take part of it. A temporary solution was found for the remaining part, involving pits dug at Angle Bay.

International co-operation

The Republic of Ireland was of course also particularly concerned by the incident, as it occurred in the Irish sea. The Irish coastline could have been polluted if the winds had been in the opposite direction. The Irish authorities were involved in the response operations.

As a member of the Bonn Agreement for co-operation in dealing with pollution by oil, the United Kingdom asked for help and advice from the other member countries. For instance, some pumps were sent from the Netherlands.

Lessons learnt from the incident

There was good cooperation between the different authorities.

An important factor in the response to this incident was the rapidity in activating contingency plans. Spraying operations were organised very quickly and the damages could have been much larger without this or if the vessel had split in two and released her cargo of 35,000 tonnes of oil.

The foggy weather did not allow aerial surveys at the beginning of the operation. Because of this, the extent of the pollution could not be assessed. If the meteorological conditions had been better it might have been possible to avoid coastal pollution.

The question of the disposal of oil was also problematic, as there was no pre-planned place to send it. This showed the importance of planning everything in advance, in case another spill occurred.



Sources:

  • HOOKE, Norman, 1997, Maritime Casualties 1963-1996, second edition, LLP Limited, London
  • NOAA, Oil spill case histories 1967-1991, Report No. HMRAD 92-11 to the US Coast Guard Research and Development Center
  • IFP, Banques de données sur les accidents de navire ayant provoqué un déversement de pétrole en mer supérieur à 500 tonnes, 1975-1979, Réf. 26 714, Janvier 1979
  • BP’s Public Affairs and Information Department, The Christos Bitas incident – Success out of a disaster, A report on the oil spill clean-up operations by BP’s Environmental Control Centre
  • Department of Trade, Christos Bitas – the fight at sea against pollution, London, 1978





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