After studying the Amazonian rainforest extensively, our scientists have arrived at their next destination-Valdez, Alaska. Here, our group will research the long-term effects of the March 23,1989, Exxon Valdez oil spill.
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We, in North America, are fortunate in having more fresh water, more fertile soils, and more resources than any other continent. Unfortunately, it is true that the oceans are “our sinks” for much of the waste that we, as a planet, produce. As Jacques Cousteau, famous oceanographer, has stated, “the very survival of the human species depends upon the maintenance of an ocean clean and alive, spreading all around the world. The ocean is our planet’s life belt. “ Effects on ecosystems by oil spills depend on various factors which include: the type of oil, amount of the spill, times of the year, weather conditions, average water temperature, ocean and tidal currents, and the distance of release from the shore.
Immediately following a spill, low-boiling hydrocarbons such as benzene and toluene cause the sudden death of shellfish and many fish in their larval forms. Other chemicals remain on the surface that adhere to sea otters, birds, rocks, and other objects. This “coat” of oil destroys the animals’ natural insulation and buoyancy. Most ultimately die from loss of body heat or drown. Heavy oil components that sink to the ocean floor have the most devastating effects on marine life. They kill crabs, oysters, clams, mussels, and completely alter all food chains. Generally, marine life can recuperate within three years of such accidents, but cold, polar waters take longer for recovery. It is generally accepted that the heavier the oil, the less toxic it is. While scientists theorize that oceans are strong and resilient, the toxification of the water is closely connected to other pollutants that threaten Earth’s biodiversity. As John Cairns, a marine ecologist, states, “should an entire ocean be damaged, the time required for recovery staggers the imagination.” Oil spills have been with us for quite a while in our history. Reports of oil damage date back to the Civil War. Back in 1912, the New York Zoological Society reported that it could not use local harbor water for its aquarium tanks because oil contamination was killing specimens.
Oil Spills II
Tanker accidents account for only 10-15% of the yearly release of oil into our oceans, but these spills have disastrous impacts on coastal regions. Nearly 50% of released oil comes from runoff and dumping of waste oil by cities. While our researchers will be studying the worst oil spill in U. S. waters, the largest accident ever took place in 1983 when the tanker Castillow de Bellver caught fire and dumped 78.5 million gallons into the waters off of Capetown, South Africa.
Since 1973, the actual number of accidents per year has decreased due to better training, and improved safety measures. However, this relaxed attitude toward standards by oil companies led to disasters such as the Exxon Valdez. Some 10,000 spills occurred in the year alone following the Exxon accident. At least three of those were in the million-gallon range. Since these smaller spills occur all of the time, the constant toxic pressure on coastal ecosystems is tremendous when accompanied by the occasional huge spill. Estimates are that anywhere from 1-10 million tons of oil are spilled each year into our oceans.
The fate of spilled oil depends on the nature of the crude. Number 6 heavy crude barely floats and is extremely viscous. Number 4, which is light crude, and Number 2 heating oil are lighter and less viscous, therefore spreading more easily across the oceans surface. These lighter oils contain more aromatic hydrocarbons and lower boiling alkanes. The low boilers induce anesthesia and narcosis among fish and invertebrates.(Taken from The Environment by Gerald Leinwand)
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Valdez, Alaska, is one of the busiest seaports in the state. Since the Alaskan pipeline opened in 1977, some 9,000 tankers have made the trip to the West Coast without any major accidents.
Oil Spills III
Much oil is pumped through an 800 mile pipeline that ends in Valdez. In Valdez, it is stored in huge storage tanks until the super tankers can take it to refineries. At the refineries, oil is made into gasoline, chemicals, plastics, and other products.
In the early 1970s, conservationists predicted there would be a large spill so they urged politicians to transport oil via a pipeline to reduce potential damage. The oil companies won by a 50-49 vote in the United States Senate. Since 70% of the worlds oil output travels by sea, it is quite apparent why the conservationists were concerned about the oceans future.
The 1989 spill, which covered some 4,000 miles of shoreline, killed hundreds of thousands of marine birds and thousands of sea otters and fish. Large, but indeterminable amounts of seals, sea lions, porpoises, dolphins, and whales are presumed dead as well. Human clean-up crews were also exposed to health risks by the toxic chemicals. Tar is fed upon by marine turtles and, accompanied by plastic garbage in the water, is a major cause of their decreasing numbers. Finally, bald eagles and other birds may also be affected indirectly through the toxins built throughout the food chain. The final toll, however, will never be known because many of the animals sank.
The area of the spill is known as Alaskas Emerald Jewel -Prince William Sound. The eleven million gallons of thick, toxic crude oil cost nearly $2 billion to clean up, making it one of the costliest spills ever. What is especially sad is that this major tragedy could have been avoided, or at the very least, controlled. Most of the clean-up measures were not effective. In hindsight, it would have cost Exxon only $22.4 million to have a second, protective hull built. The ultimate irony is that the captain of the Exxon Valdez was drunk on duty according to blood tests. His automobile drivers license was revoked due to his alcohol problems yet Exxon still let him take charge of a super tanker more than three football fields in length.
While Exxons corporate greed was a major factor in the tragedy, we as consumers must also share some of the blame. Our careless and wasteful habits have created such large demands for domestic oil. Ironically, oil carelessly dumped by consumers (from automobile, lawn, and recreational equipment) is equal in volume to twenty or more spills by the Exxon Valdez on an annual basis. The argument has been made that the Exxon Valdez was an accident, whereas our own oil spills are done with reckless intent.
Oil Spills IV
Although various clean-up techniques have been attempted, these efforts remove only a fraction of the oil at best. Skimmers and booms are used to contain and scoop up the oil. Skimmers are most effective when used on well-confined spills in relatively calm waters. Booms, on the other hand, are similar to large floating corrals. Oil-absorbing materials such as hay or plastic shavings are thrown on the spill to make it easier to pick up. Sometimes, soaps and detergents are added to reduce surface tension of the oil. The use of fire as a clean-up technique was tried back in 1967 in England but it was not very successful. Bioremediation is a fairly new idea that utilizes oil-eating bacteria to change the oil into a fatty-acid compound that is eventually decomposed by marine organisms.
During the Exxon Valdez spill, a method was attempted that actually turned out to be more destructive in the long run. The clean-up crews tried to wash the oil from the beach by using powerful streams of hot water. The ultimate effect was that this cooked marine organisms in 65øc water. Since oil spills will continue to occur, as seen recently in the Shetland Islands, solutions to this problem will come from future generations.
It is important to mention that oil spills are not the only threat to our oceans. Sewage, industrial waste, insecticides, herbicides, natural runoff, and constant polluting all account for the problems. In 1988, everyone can remember beaches along the eastern U.S. closing due to contamination from medical wastes. Every individual can do his/her part to keep our oceans clean. By conserving oil, recycling, being informed consumers, writing letters to politicians, and car pooling, we can all improve the quality of our oceans. After all, were not called the Blue Planet for nothing!
As David Bulloch aptly states in his book, The Wasted Ocean, We simply do not comprehend the extent to which we have stretched the resiliency of nature, nor do we recognize that nature, bent under these new and strange stresses, is losing its elasticity. Experience has yet to teach us that neither the private ownership of land nor the use of common water conveys the right to spoil them. Land, water, and wildlife are not artifacts along the course of civilization. They are its roots.
Our scientists have concluded the second leg of their journey. They will gather all of their data from Valdez, Alaska, and have a final report upon their return to Connecticut. Our scientific group will also present methods to stop the contamination of our oceans and various techniques to effectively clean-up oil spills.