environmental impacts : oil exploration and extraction in nigeria

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Environmental Impacts Oil Exploration and Extraction in Nigeria 2012

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Page 1: Environmental impacts : Oil Exploration and Extraction in Nigeria

Environmental ImpactsOil Exploration and Extraction in Nigeria

By:

Michelle Otutu

2012

Page 2: Environmental impacts : Oil Exploration and Extraction in Nigeria

Table of Contents

INTRODUCTION 4

CRUDE OIL EXPLORATION 5CRUDE OIL EXTRACTTION 7PRIMARY RECOVERY 9 SECONDARY RECOVERY 10 INJECTION OF FLUIDS 10 USE OF BEAM PUMPS 12 ESPS 13

TERTIARY RECOVERY 14UNCONVENTIONAL OIL EXTRACTION 15

EXTRACTION IN NIGERIA 17

THE DISCOVERY OF OIL 17OIL COMPANIES IN NIGERIA 18

THE OIL INDUSTRY AND THE NIGERIAN ENVIRONMENT 19 GAS FLARING 19OIL SPILLAGE 22COLLECTIVE CAUSES 24BIOREMEDIATION 25

CONCLUSION 27

SOURCES AND REFERENCES 28

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Dedication

This report is dedicated first and foremost to all the citizens of the Niger Delta that face struggles everyday due to the pollution of

their environment.

It is also dedicated to my dear mother for all her knowledge and support.

To Dr. Martin Tango, P.Eng for always being a source of laughter and a great Engineering mentor.

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Introduction

An oil and gas (or petroleum) reservoir is a natural deposit of a pool of hydrocarbons such as natural gas, crude oil and several other minerals. For the purpose of this report, I will be considering the exploration and extraction of crude oil in particular and excluding the inclusion of natural gas and other minerals unless required for thorough explanation or necessity.

As defined by the Concise Oxford Dictionary, petroleum is “ a liquid mixture of hydrocarbons which is present in suitable rock strata and can be extracted and refined to produce fuels which include but are not restricted to: petrol, paraffin, diesel and gasoline.” It is a naturally occurring usually highly viscous liquid composed of a variety of hydrocarbons and organic matter formed in large quantity over several millions of years under high pressures and temperatures beneath the Earth’s crust or surface. Crude oil formation occurs due to the combining of several hydrocarbons and minerals such as sulphur under very extreme pressures. Many modern day scientists have proven that most of the present day petroleum deposits and fields we have were produced after millions of years of highly pressurized activity. It is understood that the remains of plant and animal life formed petroleum fields after being compressed on sea beds by billions of tones of silt, sand and mud over a period of several millions of years. When sea animals and plants die, they will sink to the bottom of the ocean floor and begin to decompose. This decomposition takes place in the presence of sand and silt; which mixes with the biological remains. During the process of decomposition, bacteria act on the remains. This results in the removal of other elements such as phosphorus, nitrogen and oxygen from the mixture; which leaves the dead matter consisting of mostly carbon and hydrogen. The limited and insufficient supply of oxygen in the ocean floor disrupts the full decomposition of the dead biological remains. Eventually, after lying on the ocean floor for several years, the remains are buried under numerous layers of sand, silt, mud and all the minerals that are found within them. These layers create an increase in pressure; which in combination with the earth’s natural heat redefines the mixture. Thereby, forming thinner and thinner layers of the dead matter finally resulting in a semi-liquid compressed hydrocarbon mixture. This hydrocarbon mixture is the formation base of petroleum.

Most of the Earth’s petroleum and natural gas reserves were formed more than a hundred million years ago, in seas or lakes that had an abundance of microscopic plant or animal organisms. Let us examine a specific instance for clarity. Assuming the abundant organism contributing to petroleum formation is plankton: as it is in most cases. When the plankton died, it sank to the bottom of the sea or lake. If the bottom of the given water body was stagnant and lacked sufficient oxygen supply, the dead plankton accumulated in the mud and did not decay properly. This would result in a layer of mud rich in organic matter. Sediments found in water bodies such as sand, silt, stone and mud will then form layers over the inadequately decomposed supply of dead plankton. As increase in the amount of layers sediment will result in a corresponding increase in temperature and pressure acting on the dead plankton matter. This high temperature and pressure would then aid the further decomposition of the organic matter; forming shorter hydrocarbon chains, creating petroleum.

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Figure 1: Pictorial representation of the formation of petroleum. 20

Crude Oil Exploration

In recent days, petroleum products have come to be a significant natural resource in the sustainability of human comfort and everyday activities, industrialization and the provision of jobs. For petroleum to be discovered to make such a contribution, the location of an oil field must first be determined as well as quantity of the deposit. The entirety of the processes required in locating petroleum deposits is known as Exploration. A geologist usually oversees the exploration of petroleum; this process starts with the geologist examining a portion of the Earth’s surface that is suspected to contain deposits of petroleum. In the 19th century, it was observed that areas of the Earth’s surface that appeared to fold up or itself or sink several feet inwards; were most likely to contain petroleum deposits. The geologist will then proceed to carry out surveys and examinations of the rocks, soil and surrounding of the prospective petroleum reservoir. Samples will usually be obtained from surrounding water sources and surface areas. These samples will collectively be used to determine the porosity, age, permeability, formation sequence and profile of the ground within a particular area. This information will lead to the geologist being able to make an intelligent, supported and informed decision as to the likelihood of a petroleum reservoir being located within a given area.For instance, a geologist could be presented with a valley and asked to determine if its subsurface is a reservoir location. The geologist will first examine rocks in the region to aid such determination by seeing if it is even remotely possible for such an area to inhabit petroleum.

Once an area is proven to have a possibility of housing a petroleum reservoir, further tests and examinations are done to determine the precise location of the deposit and its quantity. These tests will provide a more accurate mapping of the underground conditions of the area and see if these conditions are unique with those commonly associated with petroleum reservoirs. Usually, the first process of the second round of testing is - seismic exploration. Seismic exploration of petroleum involves the application of basic concepts of seismology to aid in the determination of whether a location on the Earth’s surface is a petroleum reservoir or not. Seismology is the scientific study of earthquakes and

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the behavior of the propagation of elastic waves through the layers and surface of the Earth and similar planetary bodies. This concept is applied to petroleum reservoir determination. Elastic waves are produced artificially by the geologist or geophysicist involved. These waves are sent ripping through the Earth’s crust in areas that are suspected to house deposits of petroleum, natural gas and other minerals. The reflection of these waves back to where they were sent by the underground rock and surfaces is scientifically collected and processed. It can be seen clearly, that waves reflected from regular sub surfaces containing no deposits behave in a different manner from those reflected of sub surface rocks that are significantly more porous and permeable. Rock surfaces that are porous and permeable are much more likely to contain deposits of petroleum than those of different physical characteristics. Hence, the geologist can use such a method to ascertain if an area is in fact a petroleum reservoir.

Figure 2: Generation and reflection of artificially induced vibration waves. 19

Figure 3: Depiction of the varying reflection responses 19

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Ultimately, to conclude without any doubt that an area is indeed a location of petroleum deposits, all participating individuals looking to obtain oil must see for themselves that the area does in fact house petroleum. Therefore, the final step to be taken in the exploration of petroleum if the aforementioned procedures have been successful is the sinking of a well into ground. If substantial quantities of petroleum are found, the entire exploration process has been a success and extraction will usually follow. If no substantial quantity of petroleum is found, then the exploration team will conclude that the given area does not harbor a petroleum reservoir. According to Investopedia, an exploratory well is “a deep hole, in the Earth, that a petroleum or natural gas company drills in the hopes of locating a new source of fossil fuels. An exploratory well represents a risk for the company drilling it, because it is not known, before investing in the well, how much oil or natural gas it might contain. The well may turn out to be a profitable new source of fossil fuel, or it may contain noncommercial quantities of fuel that aren’t worth extracting; in the latter case, the well may be plugged and abandoned.”

Crude Oil Extraction

If an oil company has positive results from a petroleum exploration procedure, the process of petroleum extraction will begin. The entirety of the processes and methods required to effectively remove deposits of petroleum from under the Earth’s crust are collectively known as petroleum Extraction. Large teams of engineers, geologists, geophysicists and field officials typically carry out the extraction of petroleum. Usually, the petroleum extraction is an invasive procedure. Invasive in the sense that deep wells are drilled and high levels of environmental disruption, destruction and destabilization are observed. Historically, not all petroleum extraction procedures were invasive. Particularly, in the United Stated of America, some petroleum fields once existed where natural abundance of petroleum would rise to the surface of the Earth. This would happen either naturally, or with artificial aid by the use of steam. The majority of these fields have been used up completely; with just a few still being functional. According to George E. Totten, the earliest known oil wells were drilled and maintain in 347 CE and were located in China. These wells were very much “primitive” by today’s standards. They were up to 240 metres in depth and were drilled using bits (similar to drilling bits) attached to bamboo bark poles.

Today, the extraction of petroleum may apply a similar concept, but this concept is executed in a drastically different manner. The extraction of petroleum begins with the creation of oil (petroleum) wells. Oil wells are created by drilling a hole into the Earth’s crust with the use of an oil rig. An oil rig is simply a specialized drilling rig which is a machine used to create holes of varying length and thickness in the ground. In most cases, to get the well effectively drilled, oil companies have to engage the use of service rigs in combination with regular drilling rigs. Service rigs are used to complete the drilling process in order to get the well on line after the oil rig has created it. This allows for the oil rig to be removed and stored or perhaps used for another drilling operation. After the oil well is created, a steel pipe casing is inserted into its core to provide structural stability and integrity. Steel pipe casings (also called ‘encasement pipes’) are commonly used as a protection tools for underground constructed structures. Steel pipe casings generally have no specific specifications as maintained by any regulatory body. As long as the number one and most fundamental criteria of it is met. Most steel pipe casings are required to be extremely straight and round. Without this criteria being met, the effectiveness of the casing is significantly reduced because it has and increase chance of failure; making it particularly difficult to serve its fundamental purpose. Once the steel pipe casing has been secured, holes are made in the base of the well to allow the free flow of oil into the bore of

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the well. For the oil well to be fully structurally completed, collections of valves are fixed at the top of the well. These valves aid the regulation of pressure and flow, which is required to enable the upward flow of the crude oil being extracted. This collection of valves is sometime referred to as a ‘Christmas tree’. “In the petroleum and oil and gas industry, a Christmas tree is an assembly of valves, spools and fittings used for various well operations. It was named for its crude resemblance to a decorated Christmas tree.” The primary used of a Christmas tree is to control the flow of crude oil out of a given well. Without a Christmas tree being effectively utilized, oil may flow out at uncontrollable rates; ultimately leading to oil spillage and pollution of the surrounding areas.

Figure 4: Oil well Christmas tree 18

The above picture of a Christmas tree is a wellhead located in Northeastern area of British Columbia, Canada.

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The term “wellhead” is used to refer to the outermost portion of an oil well that is seen above the ground. It encompasses all components responsible for the maintenance of adequate steady pressures and structure.

Once the Christmas tree is fixed, the oil well is ready to be used in the recovery of crude oil and other natural resources such as natural gas. The recovery or extraction of oil is generally undertaken in three stages. These stages are thus:

I.Primary RecoveryII.Secondary Recovery; and

III.Tertiary Recovery.

Primary Recovery

This is the first stage of petroleum extraction. It is the stage where “natural reservoir energy, such as gasdrive, water drive or gravity drainage, displaces hydrocarbons from the reservoir, into the wellbore and up to surface.” 17 Gasdrive is one of the primary recovery mechanisms employed, which contains dissolved and free gas, whereby the energy of the expanding gas is used to drive crude oil from the reservoir into the wellbore. While water drive refers to a situation whereby the pressure created by free flowing water that is utilized is enough to facilitate the transportation in an upward movement of the crude oil within the reservoir up through the wellbore.

Figure 5: Gasdrive depiction 17

Primary recovery involves the use of predominantly naturally occurring mechanisms to pump out crude oil that flows to the bottom of a given oil well due to the forces of gravity. Primary crude oil

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processes are essential steps to be taken at the beginning of an oil extraction process. This is because the natural pressure within the well must first be displaced before the introduction of artificial pumps and other extraction tools. “A new well is usually under pressure from natural gas and subterranean structures. This means that the crude oil will freely flow up and out of the well through the well bore.” 24According to the National Energy Technology Laboratory of the United States of America’s Department of Energy, only about ten percent (10%) of subsurface crude oil is recovered during the primary recovery stage. Hence, the obvious need for secondary and tertiary extraction procedures. When crude oil deposits are highly viscous and are at shallow depths, primary recovery is significantly more difficult to carry out.

Secondary Recovery

After primary recovery methods, a time will usually come where the natural pressure within the wellbore is insufficient in the supply of the force needed to allow an upward flow of crude oil out of the well. Hence, several alternative and usually artificial means must be employed to continue the upward and outward flow of crude oil. Secondary recovery is enabled through the supply of external energy in to the reservoir. This external energy then improves the natural drive of the wellbore or completely replaces any non-existent drive. Thus, forming an artificial drive within the well. In order to facilitate the introduction or insertion of such artificial drive, officials in charge can employ several means to reach the desired output. These means includes but are not limited to some of the following;

1. Injection of fluids: The introduction of certain fluids down into the oil reservoir can be used to stimulate the pressure increase of the wellbore. This replaces the natural drive with an artificial drive due to fluid injection. The usual fluid of choice to be injected is water. The first recorded use of water injection was in the U.S. states of New York and Pennsylvania in the 1930s. Since then, water injection has come to be a go-to option of secondary recovery methods. Injection pumps containing water are placed at the opening of any given oil well and the bottom of the oil reservoir is filled with water at high pressures. The water acts as a piston, forcing the oil to travel in an upward displacement. The displacement of the oil does not take place in an immediate fashion. It is time consuming.

On the following page, a picture of a water injection pump is shown. The depicted pump has a flexible tubing string discharge and is upright operated. The pump system consists of a frame, coupling, centrifugal pump, and surface flange asynchronous explosion-proof motor.

It is intended to pump fresh water, stratal water and field wastewater as use for pressure modifications in secondary oil well recovery.

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Figure 6: Water Injection Pump 27

2. Use of beam pumps: Another secondary recovery means by which crude oil is recovered from under pressurized wells is through the use of beam pumps or pumping

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systems. Beam pumping systems are made up of a pump at the bottom of any given oil well, a beam-pumping unit also known as the pump jack at the surface, a rod string connecting the pump jack and the pump and a prime mover containing either an electric motor or an internal combustion engine. The prime mover acts as an energy source for the entirety of the system.

Beam pumping systems are typically made use of when the oil well being operated on is low in volume, relatively shallow in depth and contains light or medium weight crude oil.

The fundamental operation of a beam pump is shown below.

Figure 7: Drawing of a beam pumper on an oil well. 30

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3. Use of electrical submersible pumps (ESPs): These devices have airtight motors, which allow for restricting of inward gas, vapor and liquid flow. It operates on the principle of centrifugation and operates in a vertical position. Unlike other pumps that are generally used from the outer ground surface of the well, electrical submersible pumps are inserted into the well for operation. They hence generate a flow of the situated crude oil from within the oil well. Thus, making electrical submersible pumps reliable options when it comes to the provision of artificial oil well drive.

Crude oil enters the electrical submersible pump shaft, which is connected, to a gas separator via mechanical coupling at the bottom of the pump. After entering the shaft, the oil is then flowed upwards and out. The basic electrical submersible pump system is shown below:

Figure 8: A typical mechanism of the ESP system

Other lesser-used methods of secondary recovery are:

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1. Natural gas reinjection;2. Gas lift (use of air, carbon dioxide or other gases).

*Secondary recovery generally results in 30-50% of the oil reservoir being extracted.

Tertiary Recovery

This includes all extraction processes utilized after the secondary recovery stage in order to recover an even greater percentage of crude oil output. Tertiary methods of extraction are generally significantly more cost intensive than the primary and secondary recovery methods. Therefore, tertiary recovery methods are usually only performed when most of the oil in any given oil well has been collected. Thus, leaving any other remaining soil located deeply in the bedrock of the well. Because oil present during the tertiary stage of extraction is deeply rooted in rock, it is even more difficult to extract. Hence, the number one cause of the expensive nature of tertiary methods of extraction.

During the period of general extraction where tertiary methods of extraction are engaged, crude oil within the well is deeply buried, sparse and well distributed along the well bedrock. Therefore, tertiary methods of extraction are aimed to reduce the overall viscosity of the yet to be extracted crude oil. A reduction in the crude oil viscosity will allow for the molecules to flow out of the bedrock and collect together. Thus, making it easier to apply pressure to the well and remove the oil.

Typically, carbon dioxide is employed in tertiary extraction techniques to reduce viscosity and the effects of capillary action in the rock. Occasionally, detergents are also introduced into the tertiary extraction procedure to aid the reduction of surface tension between oil and water molecules within the oil well. Microbial treatments can also be utilized in tertiary extraction. Certain microorganisms help the simplification of hydrogen-carbon bonds; this helps make simpler crude oil hydrocarbons, which are thus easier to extract.

Tertiary extraction techniques allow for an additional 5-10% of crude oil deposits to be extracted.

The carbon dioxide tertiary extraction method is depicted on the following page.

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Figure 9: Carbon Dioxide tertiary extraction operations. 32

In addition to the three most used extraction methods or stages as previously stated; there are some unconventional extraction processes that are in use today. These unconventional extraction processes are known as Unconventional Oil Extraction. This extraction technique is used when deposits of crude oil are located in areas other than the conventional underground oil well deposits. Some of these unconventional deposit locations are:

1. Oil sands (such as the ones in Alberta, Canada)2. Oil shales3. Coal based liquid supplies4. Biomass-based liquid supplies5. Natural gas liquid supplies

For the purpose of this report, we will be dealing with only conventional extraction techniques and ramifications. This is because, conventional extraction techniques are significantly wider spread practiced than unconventional techniques.

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The generality of petroleum extraction techniques is depicted in the diagram below.

Figure 10: Crude oil extraction 18

Extraction in Nigeria

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Now that some background has been provided on the exploration and extraction of crude oil in general has been relayed; we will now examine the brief history of petroleum exploration and extraction in Nigeria. Hence, one will grasp a better understanding of the environmental impacts of oil exploration and extraction in Nigeria.

The Discovery of Oil

The British first discovered petroleum deposits in Nigeria in the mid to late 1950s. Ever since then, the petroleum industry has grown to be the largest industry within the country and has become a significant source of wealth. The discovery of oil in Nigeria was largely followed by heavy political and economic strife within the country. This is due to the Nigerian economy becoming heavily reliant on petroleum-generated revenue and as a result, neglecting other economic sectors within the country. The political strife is as a direct result of a combination of political desire to control oil generation within the country as well as the long history of military and civilian regimes.

Figure 11: Map of Africa with Nigeria highlighted 21

Despite the wide landmass of Nigeria, its oil is found in less than 15% of its landmass. Yet, Nigeria is one of the largest oil producing countries in the world.

“Nigeria's proven oil reserves are estimated by the U.S. United States Energy Information Administration (EIA) at between 16 and 22 billion barrels (3.5×109 m3), but other sources claim there could be as much as 35.3 billion barrels (5.61×109 m3). Its reserves make Nigeria the tenth most petroleum-rich nation, and by the far the most affluent in Africa. In mid-2001 its crude oil production was averaging around 2.2 million barrels (350,000 m³) per day.” 33

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Figure 12: Map of Nigeria with oil producing regions highlighted 21

Oil Companies in Nigeria

The oil companies within the country extract petroleum resources in Nigeria. Extraction of oil in Nigeria is unique in the sense that the entirety of oil companies within the country acts a joint venture corporation. That is, all companies are under a national umbrella of a ‘larger company’. This larger company is known as the Nigerian National Petroleum Corporation (NNPC). All companies operating in Nigeria are legally required to be sub-entities of the NNPC. Thus, incorporating the addition of “Nigeria” to its company name. Oil extraction and exploration in Nigeria is carried out between six oil companies. Namely:

1. Royal Dutch Shell (known simply as ‘Shell’) – British/Dutch2. Chevron – American3. Exxon-Mobil – American4. Agip – Italian;5. Total – French; and 6. Texaco (now merged with Chevron).

The government and each company jointly own operations in Nigeria separately. The Nigerian government own and operate at least 60% of each national oil franchise within the country; regardless of the company’s country of ownership.

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Impact of the Oil Industry on the Nigerian Environment

The region of Nigeria responsible for the harboring of approximately 100% of its petroleum reservoirs is called the Niger Delta region. The Niger Delta is simply the delta region of the Niger River, which is the largest and most influential river in West Africa. According to Nigerian geologists and officials, the Niger Delta region extends over an area of about 70,000 kilometer squares and makes up approximately 7.5% of the country’s landmass. The region is home to about 31 million Nigerian citizens and more than 50 ethnic groups. Since 1975, the Niger Delta region has been singly responsible for the provision of over 80% of the country’s oil exportation resource.

Gas Flaring

Most of the natural gas extracted from petroleum wells within the Delta region are immediately burned or flared into the surrounding atmosphere at a rate of approximately 70 million m3 of gas per day. This daily expulsion of burned gas into the atmosphere of the Niger Delta region is equivalent to about 42% of the total gas burned in the entire continent of Africa per day. Thus, severely polluting the air of the entire Niger Delta region and becoming the single most significant contributor of greenhouse emissions on Earth. It is a well-known fact that the biggest gas flaring contributors amongst oil companies in Nigeria is Shell Plc.

Annually, about 3.5 billion cubic feet of gas associated with crude oil extraction is produced in Nigeria. Unlike other countries where associated gas is reused or re-injected into the ground, Nigeria generally has at least 70% of produced associated gas burned and released into the atmosphere. This is because, it is more financially economical for oil companies to obtain gas from non-associated sources rather than separate associated gad from crude oil and other minerals from oil well extraction procedures. The high levels of gas flaring allow for the high amounts of methane distribution into the atmosphere, which is a significant contributor to global warming and climate change. In the year 2002 alone, over 35million tones of carbon dioxide were released into the atmosphere via gas flaring.

Gas flaring is a significant source of several carcinogens and poisonous chemicals. These chemicals include but are not limited to:

1. Nitrogen Dioxides2. Sulphur Dioxides3. Benzene4. Toluene5. Dioxin6. Benzapyrene7. Xylene8. Hydrogen Sulphide; and others.

Most sites of gas flaring are located close to or around communities inhabited by thousands- if not millions – of people. Towns and dwellings affected by gas flaring are often covered with soot and thick dark clouds; leading to complete damage, disruption, contamination and pollution of once viable food and water sources.

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“ In November 2005 a judgment by, "the Federal High Court of Nigeria ordered that gas flaring must stop in a Niger Delta community as it violates guaranteed constitutional rights to life and dignity. In a case brought against the Shell Petroleum Development Company of Nigeria (Shell), Justice C. V. Nwokorie ruled in Benin City that the damaging and wasteful practice of flaring cannot lawfully continue." ” 39 Despite such a public declaration of the ill effects of gas flaring, the practice continues till today.

Figure 13: Satellite view of gas flares in the Niger Delta 40

As is clearly depicted above, there is a high concentration of gas flare sites through out the entire Niger Delta region; affecting the lives and health of over 30 million people and ruining the atmospheric habitat of an area of greater that 70 000 km2 .

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Figure 14: Example of what a typical gas flare looks like 18

Oil Spillage

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Another significant source of environmental degradation in the Niger Delta region of Nigeria is oil spillage. Oil spillage is the intentional or accidental release of liquid or semi-liquid crude oil into surrounding environments. These environments encompass both water bodies and land. Oil spillage is a form of environmental pollution. Oil spills can take weeks, months of even several years to effectively clean up. Non-the-less, the damages made by oil spillage usually live on for longer periods of time even after clean ups. Spills are observed when crude oil escaped from holding takes, oil rigs, oil well, offshore platforms, pipelines and other sources. Some times, by-products of crude oil, such as gasoline, diesel and kerosene; when spilled are referred to as oil spillage. For the purpose of this report, oil spillage will only refer to the spillage of extracted crude oil.

Figure 15: Shell Oil Spill, Nigeria

In Nigeria, oil spillage is so common that many locals have come to see it as a way of life and it does not raise much concern from them. It has been estimated that over 13million barrels of oil has spilled in Nigeria since its discovery of oil in 1958. Nigerian officials have stated that over 7000 oil spill cases have been experienced between 1970 and 2000 alone.

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Oil spillage has a big impact on the environment in the Niger Delta. The ecosystem in this area had been severely damaged due to oil spillage. The Niger Delta region has abundant natural mangrove forests. Over the years, about 15% of the rich mangrove forest has been destroyed; taking with it several microorganisms and hundreds of unique plant and animal species with it. Drinking water bodies within the area have also been drastically contaminated. Most water bodies in the area have constant thin layers of oil on their surfaces. Water contamination has altered the rich aquatic habitat that was once predominant. The high levels of hydrocarbons and chemicals in natural water sources have also been a responsible factor for the presence of carcinogens in water supply for inhabiting towns and communities. Also, because oil floats on water, oxygen levels within the water become very low due to an increased difficulty in sunlight and air penetrating through the oil layer. Lack of adequate oxygen then leads to the death of aquatic organisms that require oxygen to ensure their survival. The mass death of aquatic organisms in turn, will lead to increased levels of decomposition. Overall, the stability and self-reliance of the water body is completely lost.

Overall, the effects of oil spillage can be briefly summarized under the following:

1. Destruction of the mangrove forest2. Destabilization of ecosystems3. Killing of exotic plant and animal species4. Contamination of water supply5. Widespread distribution of carcinogens6. Destruction of soil microorganisms7. Possible genetic mutation of surviving animal species8. Contamination of coastal environments

Nigerian environmental regulations are weak and not generally enforced completely and thoroughly. This allows for oil companies to engage in such environmentally detrimental practices without worrying about possible sanctions or retributions. Yet, one must remember, the Nigerian government first and foremost owns 60% of every oil company on its soil. Therefore, a greater portion of environmental responsibility falls on the shoulders of the Nigerian government and not necessarily entirely on the oil companies as one might think.

Nigeria has created the following agencies over the years to help curb environmental impacts of oil and mineral extraction:

1. Federal Environmental Protection Agency (FEPA)2. National Oil Spill Detection and Response Agency (NOSDRA)3. National Environmental Regulation and Enforcement Agency (NESREA)4. National Water Resources Institute (NWRI)5. National Agricultural Extension, Research and Liaison Services (NAERLS)6. Nigerian Agricultural and Rural Development Bank (NARDP)

*None of these agencies have succeeded in curbing or even reducing in the slightest amounts the environmental catastrophe that has been caused by petroleum extraction in the Niger Delta.

Collective Causes

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Environmental degradation faced by the Niger Delta region of Nigeria by oil spillage and well as gas flaring are caused by circumstances and lack or regulations common to both practices.

Corruption: Most Nigerian citizens and indeed individuals from other parts of the world believe that the most significant problem affecting the betterment of the environmental situation in the Delta is corruption. Nigerian officials at all levels have a long history of corruption. This includes (but not limited to); siphoning of funds made available for regulatory and enforcement operations, inflation of salaries of officials – thus reducing liquid assets available for environmental research and stability, collection of bribes from oil company officials to turn a ‘blind eye’, and so on. The totality of these and others, make it increasingly difficult to start and sustain a working approach to environmental sustainability.

Vandalism: Increasingly, instances of pipeline vandalism by locals and surrounding criminals have propagated the occurrences of oil spills. Often, oil pipelines are tapped and oil is collected for black-market sale. Persons involved in such acts generally puncture the pipelines and do not plug any holes made while tapping. These holes are left open, and oil flows out, damaging the surrounding area.

Maintenance: Pipelines in the Delta are not regularly maintained to ensure their utmost productivity. Some pipelines have been left without maintenance practices for several years according to Nigerian officials. This leads to abundant rusting, fracturing and brittleness of crude oil transportation pipelines. The pipelines are thus more prone to be a cause of spillage, which is detrimental to the immediate environment.

Regulations: Regulations that are set in place to protect the environment are largely ignored or not followed correctly.

Lack of Care: Perhaps indeed, in my opinion, the greatest cause of the environmental degradation being undergone in the Niger Delta region of Nigeria is the lack of care. Oil company officials as well as Nigerian government officials just do not seem to have enough care (and perhaps knowledge) about the true environmental implications of the processes oil extraction entails. When it comes to oil spillage, there may be less of blame to oil companies and officials, simply because of situations like vandalism, which are out of their control in most instances. But when it comes to the issue of gas flaring – oil company officials and Nigerian authority are directly responsible for environmental pollution due to flaring. I am of the adamant position the people in charge are more preoccupied with monetary gain than the maintenance of the environment that provides that monetary gain. It is a classic example of “biting the hand that feeds you”.

If the above causes are duly recognized and corrected, the negative environmental impacts in Nigeria will be significantly reduced.

Method of Correction/Proposed Solution

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The following are specific methods or means by which oil spillage and gas flaring impacts can be minimized, prevented or reversed as much as possible.

Biological Remediation: Biological remediation is the most effective and newly practiced correction technique. This is a spillage clean-up technique that involves the growth and harvesting of biological organisms capable of consuming hydrocarbons found in crude oil. Hence, biological remediation can be used to help reverse or minimize the effects of crude oil spillage in the Delta. This technique has been implemented to some degree in the Niger Delta region, but not to a large enough degree to amount in any reasonable change. The Niger Delta town of Ogbogu has used bioremediation to clean up spills in its areas. Two plant species were used as cleaning agents. These species are: Hibiscus cannabinus and Vetiveria zizanioides. The procedure involves the spreading of H.cannabinus over contaminated water bodies; since H.cannabinus has an affinity for hydrocarbons, it will absorb the oil out of the given water body. The H.cannabinus is then collected and transported to a plantation rich with V.zizanioides. V.zizanioides is a rich and deeply rooted plant that has the biological ability to absorb and break down hydrocarbons completely and detoxify soils. Hence, both organisms are used collectively to help curb soil and water contamination due to crude oil spillage. Both plants are native to Western Africa.

Figure 16: H.cannabinus 41

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Figure 17: V.zizanioides 18

Conclusion

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It is unfortunate that such mass destruction of the environment has been allowed to continue in any part of the world. As human beings, we must all remember that we are collective owners of the planet. The occurrences in one part of the planet affect us all in one way or another. In this case, the environmental degradation of one part of the planet (Nigeria) affects us all. Gas flaring that is highly practiced in the Niger Delta ultimately produces a green house affect that is detrimental to all inhabitants of the planet no matter where they are.

It is my utmost believe that the situation the Niger Delta can be duly corrected if steadfast individuals work collectively in an efficient matter. In the year 2010, the world was shocked and forced into action due to the oil spillage in the Gulf of Mexico. Sadly, that kind of international coverage has not been given to the Gulf of Guinea that borders the Niger Delta.

Indeed, after almost 60 years of contamination, we owe it to the Niger Delta and all that has been lost to correct our wrong. We owe it to the Earth and future generations to clean up.

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Sources:1. ^PetroStrategies Oil and Gas Learning Center Oil and Gas Exploration

http://www.petrostrategies.org/Learning_Center/exploration.htm

2. ^Concise Online Oxford English Dictionary http://oxforddictionaries.com/definition/petroleum?q=petroleum

3. ^E. Tzimas, (2005) (PDF). Enhanced Oil Recovery using Carbon Dioxide in the European Energy System. European Commission Joint Research Center. Retrieved 2008-08-23.

4. ^Global Marine Oil Pollution Information Gateway http://oils.gpa.unep.org/facts/extraction.htm

5. The Encyclopedia of Earth: Structure of the Earth NCSE Boston University

6. ^Petroleum Formation http://www.petroleum.co.uk/formation/

7. Figure 1: Chemistry A Cultural Approach http://www.m2c3.com/chemistry/VLI/M3_Topic1/M3_Topic1_print.html

8. http://www.naturalgas.org/naturalgas/exploration.asp

9. Figure 2: The Encyclopedia of Earth: Structure of the Earth NCSE Boston University

10. Investopedia Definitions http://www.investopedia.com/terms/e/exploratory-well.asp#axzz1qplpZSsF

11. ^ "New Billions In Oil" Popular Mechanics, March 1933 -- ie article on invention of water injection and detergents for oil recovery

12. Mines, R.O. and Lackey, L.W., "Introduction to Environmental Engineering", Prentice Hall/Pearson (2009).

13. A Timeline of Highlights From The Histories of ASTM Committee D02 and the Petroleum Industry; George E. Totten, Ph.D.

14. ^GE Energy, Oil and Gas

15. API Specifications 6A and 17D

16. Oilfield Glossary http://oilgasglossary.com/wellhead.html

17. Schlumberger Oilfield Glossary

18. Wikipedia Encyclopedia

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19. Britannica Encyclopedia

20. Bing Images

21. Google Images

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23. Definition of Primary Oil Recovery http://ehow.com/

24. Susan Kristoff; Featured Writer for Engineering. Suite101.com

25. ^ "Failing Oil Fields Revived by Action of Water" Popular Mechanics, December 1930, left-column mid page

26. Roemex Limited; water injection. http://www.roemex.com/production/water_injection.htm

27. JSC ALNAS http://en.alnas.ru/products/ecna-ppd/y-ecna-ksh/

28. Human Development Consultants: http://www.hdc.ca/product_samples/pumpjack_a.pdf

29. Husky Energy Inc.

30. Lewis Morburg’s Internet Oil and Gas Newsletter. http://www.mosburgoil-gas.com/

31. Lyons, William C., ed. (1996). Standard Handbook of Petroleum & Natural Gas Engineering. 2 (6 ed.). Gulf Professional Publishing

32. Denbury Resources Inc. http://i.bnet.com/blogs/carbon-dioxide-tertiary-recovery-method.jpg?tag=contentMain;contentBody

33. ^ U.S. Energy Information Administration (U.S. EIA), “Nigeria Country Analysis Brief,” December 1997.

34. ^Amnesty International. (2006). Nigeria: Oil, Poverty and Violence. Retrieved 9 May 2007, from http://web.amnesty.org/library/index/ENGAFR440172006?open&of=ENG-NGA

35. Shell International Petroleum Company, Developments in Nigeria (London: 1995)

36. CRS Report for Congress, Nigeria: Current Issues Updated January 30, 2008

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37. Pearson, Scott R. Petroleum and the Nigerian Economy”. Stanford: Stanford University Press, 1970. p. 13.

38. ^ "Gas Flaring in Nigeria". Friends of the Earth. Oct. 2004. Retrieved 24 Jan. 2009.

39. Egan, J. (1999). Troubled Times in the Niger Delta. Retrieved 8 May 2007, from http://news.bbc.co.uk/2/hi/programes/crossing-continents/325300.stm

40. Global Gas Flaring Satellite Survey: http://www.treehugger.com/clean-technology/global-gas-flaring-satellite-survey-reveals-oils-hidden-costs.html

41. Vegetables/Legumes Record Display http://database.prota.org/PROTAhtml/Hibiscus%20cannabinus_En.htm

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