Oil Spill Causes

Since 1970, around the world, there have been many different causes for the occurrence of oil tanker spills. For the period 1970-2013, the percentages of such spill incidences greater than 700 tons by cause are presented in Table 6.5 [42]. 

It is interesting to note from Tables 6.5 and 6.6 that two highest percentages of causes for the spill incidences greater than 700 tons and for the spills between 7 and 700 tons are grounding and allision/collision. In contrast, the percentages of these two causes for the spills less than 7 tons are on the lower end (i.e., grounding 3% and allision/collision 2%). 

Additional information on the oil spill causes is available in Reference 42. 

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Oil spills cause significant environmental problems. The largest spill in history was the deliberate release of oil into the Persian Gulf during the 1991 Gulf War. The second largest spill took place in 1979 when an exploratory well off the coast of Mexico released about 140 million gallons of oil. 

Go to the web site above to learn about the famous oil spill caused by the Exxon Valdez. 

Chapter 5 is devoted to safety in offshore oil and gas industry. Some of the topics covered in this chapter are offshore industrial sector risk picture, offshore worker situation awareness concept, offshore industry accident reporting approach, and offshore industry accidents case studies. Chapter 6 is devoted to case studies of oil tanker spill-related accidents, oil tanker spill analysis, and oil spill causes. Chapter 7 presents various important aspects of human factors contribution to accidents in the oil and gas industry and fatalities in the industry. Some of the topics covered in this chapter are human factors that affect safety in general, categorization of accident-related human factors in the industrial sector, categories of human factors accident causation in the oil industry, and recommendations to reduce fatal oil and gas industry incidents. Chapter 8 is devoted to case studies of maintenance influence on major accidents in the oil and gas industry and safety-instrumented systems and their spurious activation in the oil and gas industry. 

Oil Spills. Oil spills occur from oil pipeline leaks, oil tanker accidents, or submarine oil drilling operations. The two major ocean drilling accidents—oil wells blowing out—were the 1969 Santa Barbara Channel spill and the 1979 Yucatan Peninsula spill, in Mexico. The Yucatan spill spewed out more than three million barrels before being capped in 1980. Both caused damage to beaches and marine life, but the smaller Santa Barbara spill was far more devastating because of unfavorable winds following the accident. 

Environmental Health Criteria 202 (1998). WHO, Geneva—Gives a very detailed account of the environmental toxicology of PAHs seen from the global point of view. However, it largely ignores marine pollution caused by oil spills. 

Demulsifiers (specifically, oil spill demulsifiers) can be applied to oil spills in low concentrations. They prevent mousse formation for significant periods of time and cause a large reduction in oil-water interfacial tension. The best of these was found to prevent emulsification at dosages as low as 1 part inhibitor to 20,000 parts of fresh oil at 20° C [273]. At dosages of 1 1000, at temperatures higher than 10° C, the chemical also results in significant and rapid dispersion of the oil. For very low temperatures or highly weathered oil, the performance of the chemical falls off sharply. 

M. F. Fingas, D. Kyle, and E. Tennyson. Dispersant effectiveness Studies into the causes of effectiveness variations. In Proceedings Volume, pages 92-132. 2nd ASTM Use of Chem in Oil Spill Response Symp (Victoria, Canada, 10/10-10/11), 1994. 

In view of these complexities, environmental studies that seek to verify proposed cause-effect relationships between contamination and response need to be carefully designed to avoid bias and misunderstanding. Most environmental assessments adopt a multi-tiered approach to testing, in which combinations of biological responses (biomarkers) are measured in tissue samples, body fluids or at the whole organism level to indicate exposure to or adverse effects of contamination.8. Auffret and colleagues60 surveyed Pacific oysters from the Atlantic coast of Brittany after the Erika oil spill between... 

The density of crude oil is on the order of 0.85 g/cm, so if the sea surface is calm, an oil spill will initially form a slick. The slick is subject to physical processes, such as advection and turbulence, causing it to move vertically and/or horizontally. Advection tends to lead to dispersal or, if land is nearby, shoreline stranding. Turbulence promotes the formation of emulsions, called chocolate mousse, which can be transformed via weathering into tarballs. The lower-molecular-weight compounds tend to evaporate or dissolve. Some fractions of petroleum have solubilities in seawater on the order of tens of milligrams per liter. Some are also photochemically oxidized. 

Description Petroleum resulting from oil spills often pollutes water bodies. Large-scale accidents are also an important cause of pollution along shore lines. The most well-known example is the Exxon Valdez oil spill. 

Between 1985 and 1991,1726 natural gas pipeline ruptures andleakages were reported in the United States. These incidents resulted in 634 injuries and 131 fatalities. Third-party damage was the most common cause of these incidents, followed by corrosion. The GAO believes that the corrosion-related incidents can be reduced with the use of smart pigs (46). U.S. DOT 1992 accident statistics showed that 52.5% of U.S. oil spills involving loss of at least 1590 m3 came from pipeline accidents, comparable to the worldwide statistic of 51.5%. The U.S. DOT regulated 344,575 km of liquids pipelines during the 10-yr study period and received reports on 1901 accidents during that time thus the number of failures per year per 1000 miles was 0.888, of which 27% was due to corrosion and 31% to outside forces (48). 

Oil spills can catch fire and cause air pollution. Oil refineries catching fire, caused air pollution as well. 

PAHs are released to the environment from a number of sources pyrogenic sources including fossil fuel combustion and pyrolytic processes of organic matter such as incineration and petrogenic sources such as oils spills. Direct oil spilled from stationary sources and accidents cause contamination of land. Oil spills at US Army bases in South Korea is reported as a source of soil and groundwater contamination to nearby area... 

Marine oil spills can cause significant environmental damage. When a crude oil is spilled at sea several processes can occur (Figure 9.5) [552]. Immediately following a spill, a slick is formed which spreads out from the source [553,554]. Studies of the spreading of the spilled oil have been carried out by a number of researchers [553,555-561], Next there is the potential for the formation of two quite different kinds of emulsions. 

In addition to drifting and evaporation, wind and wave energy advection and turbulence can cause an O/W emulsion to be formed which helps disperse oil into the water column and away from sensitive shorelines [562,563]. These droplets typically become weathered, accumulate suspended fine solids, and settle out [564—567]. For this reason oil-spill response teams may actually promote the formation of O/W emulsions from oil in the slick. 

As a source of clean energy, hydrogen is also going to be the permanent answer to another global problem caused by utilization of fossil fuels, such as the greenhouse effect, climate change, acid rains, ozone layer depletion, pollution and oil spills. 

Developed nations, such as Canada, depend heavily on petroleum. Our dependence affects the environment in many ways. Oil spills are a dramatic example of environmental harm caused by petrochemicals. In the news, you may have seen oceans on fire and wildlife choked with tar. What can we do ... 

The accidental destruction of oil tanks at the Sendai Refinery of Tohoku Petroleum Co. in the Miyagi Offshore Earthquake, although fire did not break out, caused the second greatest amount of damage next to that in the Niigata Earthquake in the Japanese oil complexes. A huge amount of oil spilled on the land and into the sea. Chisaki 4 described the scene of this oil leakage as follows. 

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