8 Oil Pollution in Coastal Waters of Nigeria
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greenhouse gas emissions on the planet. Gas flaring in Nigeria releases large amounts
of methane and carbon dioxide, which have very high global warming effect. Gas
flares release a number of poisonous chemicals such as nitrogen dioxides, sulphur
dioxide, volatile organic compounds like benzene, toluene, xylene and hydrogen
sulfide, as well as carcinogens like benzapyrene and dioxin (Nwilo and Badejo 2001,
2007; Wikipedia 2012a). It is well known that gas flaring is a major contributor to
air pollution and acid rains.
The Nigerian officials (Department of Petroleum Resources in Nigeria) estimated
1.89 mln barrels of petroleum were spilled into the Niger Delta between 1976 and
1996 out of a total of 2.4 mln barrels spilled in 4,835 incidents. The UNDP report
shows a total of 6,817 oil spills between 1976 and 2001, which account for a loss of
3 million barrels of oil, of which more than 70 % was not recovered. The Nigerian
National Petroleum Corporation reports that an average 300 individual large oil
spills of a total 2,300 m
3 annually poison the environment. World Bank estimates
this quantity as ten times larger. In 2010 Baird reported that between 9 and 13 million
barrels have been spilled in the Niger Delta since 1958. Maximal estimates of the
total amount of petroleum spilled between 1960 and 1997 reach 100 million barrels,
or 16,000,000 m
3 (Wikipedia 2012b).
There are different and even unusual (for example, sabotage) causes for oil pollution in Nigeria. They include: corrosion of pipelines and tankers (50 % of all spills),
sabotage (28 %), oil production operations (21 %), and inadequate or non-functional
production equipment (1 %) (Nwilo and Badejo 2001, 2007; Wikipedia 2012b). Corrosion of pipelines is a main reason, which is explained by an extensive network of
pipelines and small flowlines connecting the small size oil fields and oil flowstations.
In onshore areas most pipelines and flowlines are laid above ground for 30–50 years.
With a life span of about fifteen years, corrosion allows many opportunities for leaks.
Sabotage is performed primarily through what is known as "bunkering", whereby
the saboteur attempts to tap the pipeline. Theft of oil through oil siphoning has become a major issue also. In the process of oil extraction sometimes the pipeline is
damaged or destroyed with leakages for several days (Nwilo and Badejo 2001, 2007;
Wikipedia 2012b).
Oil spills have a major impact on the environment and ecosystem of the Niger
Delta and coastal zone. Available records for the period 1976 to 1996 indicate that
approximately 6, 25, and 69 % respectively, of total oil spilled in the Niger Delta
area, were in land, swamp and offshore environments (Nwilo and Badejo 2001, 2007;
Egberongbe et al. 2006). Oil kills plants and animals in the estuarine zone, settles on
beaches and kills organisms that live there, settles on the ocean floor and kills benthic
organisms such as crabs. Oil poisons algae, disrupts major food chains, decreases
the yield of edible crustaceans, affects birds, contaminates commercially valuable
fish in coastal zone (Nwilo and Badejo 2001, 2007). Oil contamination affects the
population of nearly 250 species of fish, of which 20 are endemic. The mangrove
and rain forests, especially vulnerable to oil, have been significantly destroyed.
In the populated areas agriculture, aquaculture and fishery are developing under
the pressure of hydrocarbons contamination of soils, groundwater, freshwater and
seawater.
153
greenhouse gas emissions on the planet. Gas flaring in Nigeria releases large amounts
of methane and carbon dioxide, which have very high global warming effect. Gas
flares release a number of poisonous chemicals such as nitrogen dioxides, sulphur
dioxide, volatile organic compounds like benzene, toluene, xylene and hydrogen
sulfide, as well as carcinogens like benzapyrene and dioxin (Nwilo and Badejo 2001,
2007; Wikipedia 2012a). It is well known that gas flaring is a major contributor to
air pollution and acid rains.
The Nigerian officials (Department of Petroleum Resources in Nigeria) estimated
1.89 mln barrels of petroleum were spilled into the Niger Delta between 1976 and
1996 out of a total of 2.4 mln barrels spilled in 4,835 incidents. The UNDP report
shows a total of 6,817 oil spills between 1976 and 2001, which account for a loss of
3 million barrels of oil, of which more than 70 % was not recovered. The Nigerian
National Petroleum Corporation reports that an average 300 individual large oil
spills of a total 2,300 m
3 annually poison the environment. World Bank estimates
this quantity as ten times larger. In 2010 Baird reported that between 9 and 13 million
barrels have been spilled in the Niger Delta since 1958. Maximal estimates of the
total amount of petroleum spilled between 1960 and 1997 reach 100 million barrels,
or 16,000,000 m
3 (Wikipedia 2012b).
There are different and even unusual (for example, sabotage) causes for oil pollution in Nigeria. They include: corrosion of pipelines and tankers (50 % of all spills),
sabotage (28 %), oil production operations (21 %), and inadequate or non-functional
production equipment (1 %) (Nwilo and Badejo 2001, 2007; Wikipedia 2012b). Corrosion of pipelines is a main reason, which is explained by an extensive network of
pipelines and small flowlines connecting the small size oil fields and oil flowstations.
In onshore areas most pipelines and flowlines are laid above ground for 30–50 years.
With a life span of about fifteen years, corrosion allows many opportunities for leaks.
Sabotage is performed primarily through what is known as "bunkering", whereby
the saboteur attempts to tap the pipeline. Theft of oil through oil siphoning has become a major issue also. In the process of oil extraction sometimes the pipeline is
damaged or destroyed with leakages for several days (Nwilo and Badejo 2001, 2007;
Wikipedia 2012b).
Oil spills have a major impact on the environment and ecosystem of the Niger
Delta and coastal zone. Available records for the period 1976 to 1996 indicate that
approximately 6, 25, and 69 % respectively, of total oil spilled in the Niger Delta
area, were in land, swamp and offshore environments (Nwilo and Badejo 2001, 2007;
Egberongbe et al. 2006). Oil kills plants and animals in the estuarine zone, settles on
beaches and kills organisms that live there, settles on the ocean floor and kills benthic
organisms such as crabs. Oil poisons algae, disrupts major food chains, decreases
the yield of edible crustaceans, affects birds, contaminates commercially valuable
fish in coastal zone (Nwilo and Badejo 2001, 2007). Oil contamination affects the
population of nearly 250 species of fish, of which 20 are endemic. The mangrove
and rain forests, especially vulnerable to oil, have been significantly destroyed.
In the populated areas agriculture, aquaculture and fishery are developing under
the pressure of hydrocarbons contamination of soils, groundwater, freshwater and
seawater.