Incident
Name: Torrey Canyon
Subject:
USCG Case History
Incident Date:
3/18/1967
Incident Location:
Lands End, England
Author:
USCG Case History
Latitude:
50 03 N
Longitude:
004 44 W
Product:
Kuwait crude oil
Type: 3
Volume:
860000
Source:Tank Vessel
RAR: Abundant shellfish beds, shorebirds, waterfowl, diving birds, bird nesting beaches, oysters, crabs.
Dispersants:
Yes
Bioremediation:
No
In-Situ Burning:
Yes
Special Interest
Topic(s): Habitat impact due to cleanup operations, research conducted, wildlife impacts, wildlife rehabilitation
Shoreline Type(s)
Impacted: sand/gravel beaches, exposed rocky shores.
Summary:
On the morning of March 18, 1967, the T/V Torrey Canyon ran aground on Pollard Rock on Seven Stones Reef off Lands End in England due to the master's negligence. The entire cargo, approximately 860,000 barrels (references range between 857,600 and 872,300 barrels), was released into the sea or burned during the next twelve days. Ships of the Royal Navy carrying detergents were en route to the scene within four hours of the grounding.
The response command post was established at Plymouth. The Royal Air Force and the Royal Navy implemented an early warning system for oil movement. A panel of expert scientists was assembled to consider scientific problems involved with the cleanup procedure. Local authorities were instrumental in dealing with the oil beached within their jurisdictions.
A detergent, primarily BP1002, was sprayed on much of the floating oil to emulsify and disperse it. Manual methods were used for removal of oil on many of the sandy beaches, although the dissected nature of the shoreline made it impossible to clean the whole coastline. The vessel lost structural integrity on March 26, releasing more oil into the water. Since towing the vessel off of the reef was deemed impossible, the government decided to bomb the vessel.
Behavior:
Kuwait Export crude oil has an API gravity of 31.4, and a pour point of 0 degrees F. The spilled oil formed three distinct slicks. The first slick, composed of approximately 219,900 barrels, drifted up the English Channel, oiling the north coasts of France and Guernsey. The following week, about 146,600 more barrels escaped the vessel. Approximately 102,620 barrels of this second pulse stranded on 200 miles of the coast of West Cornwall. One hundred miles of coastline between Perranporth and The Lizard, at the southern tip of Cornwall, were affected. The third slick, estimated at 366,500 barrels, formed on March 26 when the vessel broke up. This slick drifted south into the Bay of Biscay and remained at sea for two months, during which time as much as 50 percent of the lighter fractions of the oil evaporated The west coast of Brittany was only lightly oiled.
The formation of water-in-oil emulsions, containing up to 80 percent water, greatly increased the volume of material and its resistance to dispersants. Approximately half of the cargo did not reach the shore because it weathered, evaporated, or was dispersed by natural mechanisms. For several months following the dispersant application, many shorelines were recoated with oil-dispersant mixtures.
Countermeasures/Mitigation: Over 10,000 tons of detergents, primarily BP1002, which contained 12 percent nonionic surfactant and 3 percent stabilizer, were sprayed on the floating oil to emulsify and disperse it. Forty-two vessels were chartered for the spraying operation. Concentrations of 10 parts per million or less of these detergents were acutely toxic to many marine mammals and plants. Many limpets on intertidal rocks in the spray area were killed. A prodigious growth of green weed occurred due to enhanced nutrients from the dispersants. Detergents were not used on the 40-mile long coastal section between Trebeurden and Ile de Brehat so that inshore shellfish would not be contaminated with toxic components of detergents.\\Manual removal methods, including the use of straw and gorse to soak up oil, were used on many of the sandy beaches on the north coast of Brittany. Cleanup operations included pumping and bailing of oil as well as bulldozing of oiled sand on the beaches. Over 1,400 personnel from the British armed services assisted with beach cleanup. Approximately 4,000 tons of oil and oil emulsions were removed from the foreshores of Guernsey and 4,200 tons were removed from French beaches.\\The French treated floating oil with approximately 3,000 tons of natural chalk containing stearic acid which made the chalk oleophilic. It was believed that this chalk caused the oil to sink or disperse. The high density of the floating oil, the length of time the oil had been at sea, and relatively calm seas contributed to the apparent success of this method.\\After considering the options of towing the vessel or attempting to pump oil off the vessel while it was still on the reef, government authorities decided to bomb the vessel to burn the remaining oil. The vessel was bombed by the Royal Navy on March 28-30 during periods of low water when the vessel was in clear view. A Navy helicopter dropped napalm, sodium chlorate, and aviation fuel to fuel the fire.
Other Special
Interest(s): This incident prompted the English Government to take the initiative in organizing an early meeting of the Intergovernmental Maritime Consultative Organization to consider needed changes in international maritime law and practice. Relevant maritime laws were considered to be overly complex and out of date in many respects.\\An estimated 25,000 birds died as a result of the Torrey Canyon spill because the incident coincided with their northerly migration. The coasts of southern England and Brittany are nesting beaches for a variety of seabirds such as guillemots, razorbills, shags, puffins, and Great Northern divers. Thousands of oiled birds were picked up from the beaches for treatment, but the survival rate was only around one percent due to ingestion of oil, pneumonia, and improper handling and cleaning.\\The Torrey Canyon incident was the first incident to draw universal attention to the dangers of dispersants. Extremely large quantities of dispersants were used during the response, clearly for aesthetic and not ecological purposes. Contamination by oil without dispersants resulted in less adverse biological effect than where dispersants were used. Many herbivores, mainly limpets, and some barnacles were killed due to the toxicity of the dispersant. Widespread mortalities on the West Cornish coast set the stage for a large-scale experiment on the development of a mature community, normally found on rocky shores, and the influence of herbivores and predators on the ecosystem. However, the resultant statistical comparisons may be somewhat inaccurate due to the small amount of pre-spill data, the lack of control sites where the oil was left totally untreated, and uncertainties of how much dispersant reached marginal areas. Early estimates indicated rapid recovery of species along the beach, while long term studies revealed extremely slow recovery. Wave-beaten rocky areas that received only light oiling took approximately 5-8 years to return to normal while areas receiving heavy and repeated dispersant applications took 9-10 years to recover. A 1978 study showed that a rare hermit crab species had not re-appeared in the spill area.
References:
1991 World Almanac
8/9/91 & 8/28/91 Letters from Daniel Owen at ITOPF
Hooke, N. Modern Shipping Disasters 1963-1987. Lloyds of London Press. 1987.
National Research Council. Using Oil Spill Dispersants on the Sea. National Academy Press, Washington, D.C. 1989. pp.318-319.
Oil on the Sea, David P. Hoult, 1969
Potter, J. Disaster by Oil. Oil Spills: Why They Happen, What They Do, How We Can End Them. Macmillan Co., New York. 1973.
Review of Oil Spill Occurrences and Impacts, Exxon Production Research Company, 1989.
Tanker Advisory Center, Inc. 1991 Guide for the Selection of Tankers. T.A.C. Inc. 1991.
The SocioEconomic Impacts of Oil Spills, Final Report, WAPORA, March 1984.
The Torrey Canyon, Her Majesty's Stationary Office, April 1967
Wilson, M.P. Jr., et al., "The Spreading, Retention and Clean-up of Oil Spills," URI, Kingston, RI, 1976.
Last Edit:
9/21/92
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