Over two decades after the devastating Exxon Valdez oil
spill off the coast of Alaska,
significant quantities of oil can still be found covering the state's shores
and beneath gravel beaches, a new study has discovered. Over 21,000 gallons of
crude oil remains of the 11 million gallons of crude oil that gushed from the
stranded tanker Exxon Valdez on the night of 23 March 1989. Traces of Valdez's oil have been detected as far as 724km away from
the spill-site in Prince William Sound, and the toxic film that coats Alaska's shores remain a
danger to wildlife, entire eco-systems and the lives of local people.
Noted: One tonne = approx. 308 US gallons
1. Gulf War oil spill - 1,500,000 tonnes
The Gulf War oil spill is regarded as the worst oil spill in
history, resulting from actions taken during the Gulf War in 1991 by the Iraq military. It
caused considerable damage to wildlife in the Persian Gulf especially in areas
surrounding Kuwait and Iraq. Estimates
on the volume spilled range from 42 to 462 million gallons; the slick reached a
maximum size of 101 by 42 miles and was 5 inches thick. Despite the uncertainty
surrounding the size of the spill, figures place it 5 to 27 times the size (in
gallons spilled) of the Exxon Valdez oil spill, and more than twice the size of
the 1979 Ixtoc I blow-out in the Gulf of Mexico. According to a study sponsored by UNESCO, Bahrain, Iran,
Iraq, Kuwait, Oman,
Qatar, Saudi Arabia, the United
Arab Emirates and the United States, the spill did little
long-term damage. About half the oil evaporated, a million barrels were
recovered and 2 million to 3 million barrels washed ashore, mainly in Saudi Arabia. On January 21, 1991, Iraqi forces opened valves at the Sea Island
oil terminal and dumped oil from several tankers into the Persian
Gulf. The apparent strategic goal was to foil a potential landing
by U.S. Marines. The oil moved southward, ending up on the north coast of Saudi Arabia,
endangering the fragile intertidal zones and mangrove forests and destroying
wildlife habitats.
2. Ixtoc I oil well – 480,000 tonnes
Ixtoc I was an exploratory oil well in the Gulf of Mexico,
about 600 miles (970 km) south of the U.S. state of Texas. On June 3, 1979, the
well suffered a blowout and is recognized as the second largest oil spill in
history. Mexico's
government-owned oil company Pemex (Petróleos Mexicanos) was drilling a 2-mile
(3.2 km) deep oil well, when the drilling rig lost drilling mud circulation. In
modern rotary drilling, mud is circulated down the drill pipe and back up the
casing to the surface. The goal is to equalize the pressure through the shaft
and to monitor the returning mud for gas. Without the circulating mud, the
drill ran into high pressure gas which blew out the oil (known as a blowout).
The oil caught fire and the platform collapsed. In the next few months, experts were brought in to contain
and cap the oil well. Approximately 10 thousand to 30 thousand barrels per day
were discharged into the Gulf until it was finally capped on March 23, 1980.
Prevailing currents carried the oil towards the Texas coastline. The US government
had two months to prepare booms to protect major inlets. Mexico rejected
US requests to be compensated for cleanup costs.
3. Atlantic Empress / Aegean Captain – 287,000 tonnes
The Atlantic Empress was a Greek oil tanker that was
involved in two large oil spills. The spills together are the fourth largest
total oil spill on record and the largest ship-based spill. On July 19, 1979, during a tropical rainstorm, the ship
collided with the Aegean Captain, off Trinidad and Tobago, spilling
287,000 metric tonnes of oil consigned to Mobil. The damage incurred from the
collision was never completely remedied, and while being towed on August 2, the
Atlantic Empress continued to spill an additional 41 million gallons (all
together being 276,000 tonnes of crude oil) off Barbados. The Aegean Captain also
spilled a large quantity of oil from her No. 1 tank. The Atlantic Empress sank
on 3 August in deep water and her remaining cargo solidified. The spill from
the two ships fortunately never came ashore.
4. Fergana
Valley – 285,000 tonnes
Location: Uzbekistan
Date: March 2, 1992
88 million gallons of oil spilled from an oil well. (No more
information)
5. Nowruz oil field – 260,000 tones
In 1983, the Nowruz Oil Field in the Persian Gulf, Iran, was
involved in a number of oil pollution incidents. On February 10, 1983, a tanker
collided with a platform. The platform developed a 45-degree tilt and had to be
shut down. Wave action and corrosion apparently caused the riser to collapse
into the wellhead causing a spill of approximately 1,500 barrels per day. The
well was not capped because the field was in the middle of the Iran/Iraq war
zone. This platform was attacked by Iraqi planes in March and the resulting
slick caught fire. This well was capped by the Iranians on September 18, 1983.
Eleven people were killed during the operation. In March 1983, a nearby
platform was attacked with rockets by Iraqi helicopters. The platform burned
and spilled oil at an initial rate of approximately 5,000 barrels per day. The
rate slowed to about 1,500 barrels per day in the two years before the well was
capped. In May 1985, the fire was extinguished and the well was plugged with
the assistance of divers. Nine men died during these operations. Approximately
733,000 barrels of oil spilled into the sea as a result of this incident. It is
estimated that the rate of oil leaking into the Persian
Gulf in mid-May of 1983 was between 4,000 and 10,000 barrels per
day due to more war-related activity or the collapse of burning platforms. As a
result of this incident, a cooperative program for large-scale trajectory
modeling was developed between the National Oceanic and Atmospheric
Administration and Kuwait's
Environment Protection Council under the Ministry of Public Health.
Source: http://www.worldsbiggests.com
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