Incident Name: General Colocotronis
Subject: USCG Case History
Incident Date: 3/7/1968
Incident Location: Eleuthera Island, Bahamas
Author: USCG Case History
Latitude: 25 20 N
Longitude: 076 20 W
USCG District: 7
Product: Venezuelan crude oil, diesel fuel
Type: 3, 2
Volume: 37700
Source:Tank Vessel
RAR: Coral reefs, recreational beaches, crabs, lobster.
Dispersants: Yes
Bioremediation: No
In-Situ Burning: Yes
Special Interest Topic(s): Adverse weather conditions, complex salvage operations, research conducted, effects to tourism, unusual or experimental cleanup techniques.
Shoreline Type(s) Impacted: Coral reefs, fine sand beaches.
Summary: On March 7, 1968, the Greek tank vessel General Colocotronis ran aground on the east side of Eleuthera Island in the Bahamas. The vessel was loaded with approximately 119,000 barrels of Venezuelan crude oil. The hull was severely damaged during the grounding causing the vessel to spill approximately 37,000 barrels of oil into the Atlantic Ocean at a location one and one-half miles offshore.
Approximately 72,500 barrels of oil were pumped from the vessel into another tanker, the Esso Margarita. Steam lines were rigged to heat the cargo to facilitate pumping. Moving the salvage vessels into position and offloading the remaining cargo was performed during extremely severe weather.
Dive surveys reported that the keel was crushed and buckled and that there was extensive damage to the hull of the vessel. Salvage and response personnel decided that the only feasible action was to sink the General Colocotronis. Following the offloading operations, the cargo tanks were flushed with dispersants to remove the residual oil. The vessel was then towed out to deep water and sunk.
Behavior: Approximately 37,000 barrels of crude oil rapidly spilled from the General Colocotronis. The resulting slick spread out along the coast and caused impacted recreational beaches and private residential shoreline. In addition to the spilled cargo, an unknown quantity of the vessel's diesel bunker fuel also leaked out.
The oil impacted the sands of Eleuthera, in some cases penetrating deep into the beach sand and forming layers as thick as two inches. The coral reef was covered with oil. The slick offshore was 14 miles long by two miles wide.
Countermeasures/Mitigation: The primary response tool for this spill was chemical dispersant. Four types of dispersants were reportedly used during the cleanup operation: Enjay 7664, Magnus, Drew, and Polycomplex A. A total of 10,900 gallons of dispersants were used to combat the oil slick. The water-based Enjay 7664 was only recently on the market at the time of the spill and was proven by tests conducted at Eleuthera to be of low toxicity. Polycomplex A was also water-based. Magnus was a light-oil base and was used in limited amounts. Drew was a kerosene based product that produced a slight skin-irritation to the cleanup personnel who worked with it. Tropical weather conditions reportedly made personal protective equipment impractical. \\Oil was sprayed with detergents while it was still on the water but close to the shoreline. This was done by spraying the detergent into the breakers from on shore or from a small boat close to the shore. \\There was a very high rate of "bio-erosion" that effectively cleaned the intertidal coral reefs. Particularly noted were the chiton and other browsing molluscs. They were shown to clean up oil on the reefs rapidly. \\Sea grass and Sargassum weed were natural sorbents. These weeds washed up on the shore naturally and absorbed the oil as it hit the beach. \\Boom was used at the north end of the beach at French Leave. This booming was felt to have only psychological value and it was not believed that the boom could have held back the heavy crude oil.
Other Special Interest(s): A test of burning dry weed that had been used to mop up oil was conducted. This was determined to be impractical on a larger scale as the fire was quickly buried in sand or wet weeds. There was also a potential risk of the fire spreading to the dry scrub in the back-beach area. \\Foam tankers and pump trucks for fire fighting were used in the dispersant spraying operation. They were used from the beaches and from landing craft. \\This spill occurred four days after the Ocean Eagle spill in Puerto Rico. Most of the media attention was focused on that incident. There were no reported adverse effects to the tourist industry of the area as a result of the spill.
References: Genwest Systems, Inc. communications with ITOPF representatives.
Gilmore et al. 1970. Systems Study of Oil Spill Cleanup Procedures. Vol.1: Analysis of Oil Spills and Control Measures.
Hooke, N. Modern Shipping Disasters 1963-1987. Lloyds of London Press. 1987.
Potter, J. 1973. Disaster By Oil. The Macmillan Company, NY. pp. 119-151.
Last Edit: 9/18/92
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