Petroleum industry and its pollution potential in Nigeria

Oil & Petrochemical Pollution 2 (1985) 223-229

Petroleum Industry and its Pollution Potential in Nigeria O. ODEYEMI and O. A. OGUNSEITAN Department of Microbiology, University of Ife, Ile-Ife, Nigeria The increased prominence of the petroleum industry in Nigeria since the 1960shas given rise to a concomitantupsurge of real and imagined ecologicaldisturbances, especiallyin the oil-producingareas of the country. An overviewof the growth and development of the oil and petrochemical industry in Nigeria is presented. Notable cases of polluting disturbances during the 25 years of its existence are also cited to highlightthe causesand effectson the social, economic,agricultural and ecological characteristics of human and other bioticoccupantsof the oil regions. The imminent expansion schemescould expose the environmentto disturbances fromexploration and drilling activities, gas flares, refinery effluents and refractory products and massivespillagesdue to handlingoperations. The existing regulations governingthe control of environmentalpollution are viewedas inadequate and needing revision and overhauling. Recommendationsare givenas guides for the activitiesof the Nigerian National Petroleum Corporationin the prevention, control, and treatment of oil and petrochemicalpollution. 1. I N T R O D U C T I O N Since the initial discovery of oil in commercial quantity in 1956 in the River Niger delta basin of Nigeria, the commodity has steadily overtaken agriculture as the dominant source of revenue. Oil revenue supports the Nigerian economy to the extent of providing 90% of foreign exchange earnings and 85% of total government revenue. Crude oil in Nigeria will maintain its importance probably until the reserves dry up, and the current estimate of this event extends beyond the next 20 to 30 years (NNPC, 1982). The oil industry has therefore expanded tremendously and become more versatile, reaching, in one aspect or another, many more Nigerians than any other industry has, or could reach. The increased general interest in ecology and the environment, ushered in by the 1970s, did not bypass the petroleum industry. The more recent diversifications of the industry in Nigeria plus increased press coverage of localised disturbances

has caused an increased public and professional concern about health and about the environmental hazards that seem to accompany the wealth obtained from petroleum. Like other oil-producing countries, Nigeria experiences some serious problems of pollution, but each country, invariably, presents some unique conditions under which oil and petrochemical pollution occurs and how such pollutions may be prevented, treated, or controlled. This paper attempts to view the petroleum industry in Nigeria in the light of conditions that may produce environmental pollution problems through its development. 2. T H E N I G E R I A N O I L I N D U S T R Y Shell D'arcy, the pioneer oil company in Nigeria, started commercial production in 1958 at a rate of 5100 barrels per day. This quantity doubled in the following year, and 20 years later in January 1979, the rate of crude oil production reached a peak of

Olu Odeyeml is a Reader in Microbiology and formerly Head of Department of M&robiology, University of lfe. He is an Environmental Microbiologist whose special research interests include oil pollution, pesticide pollution, water quality, legume Rhizobium symbiosis, and biogas production and technology. O. A. Ogunseitan was a graduate student and Assistant Lecturer in Microbiology, University of lfe. He is currently doing his PhD in Microbial Ecology at the Department of Microbiology, University of Tennessee, Knoxville, USA. Oil & Petrochemical Pollution 0143-7127/85/$03.30--@Elsevier Applied Science Publishers Ltd, England, 1985.

Printed in Great Britain 223

224

O. ODEYEMI & O. A. OGUNSEITAN

OPP VOL. 2 NO. 3, 1985

×x" RIVER | KA NO

KADUNi ] KAINJI

JOS

MAIDUGURI

GOMBE RIVER BENUE

ILORIN MAHURDI ORE Atlas Cove LAGOS w

,,

•

>ORT,

ATLAN TIC OCEAN

Scale 1:600,000

LEGEND • Oil fields • Gas fields (~ Refineries I1~11 Depots connectedby pipelines

[] Coal mines 7. Oil exploration fields g2~ Hydroelectric power dam

Fig. 1. Location of the Nigerian oil and petrochemicalindustry. 2.44 million barrels per day (Amu, 1982). At present, through OPEC agreements, the production has dropped to about 1.5 million barrels per day. This quantity comes from the activities of 10 international oil companies working at a total of 122 fields containing over 970 oil wells (NNPC~ 1984). At present Nigeria has three oil refinerie~ (Fig. 1). The Port Harcourt refinery, which was commissioned in 1965, was built with an on-stream capacity of 60 000 barrels of light crude oil per day. The Warri refinery with a capacity of 100 000 light crude oil barrels per day was commissioned in 1978. The third refinery, built inland at Kaduna with a capacity of 100 000 barrels per day, started operations in 1980.

The Kaduna refinery is the largest and is capable of using both light, basically naphthenic, Nigerian crudes and heavier paraffinic etudes imported from Kuwait, Venezuela and Brazil to produce lubricants, waxes and asphalt. The Kaduna refinery is fed with crude oil through a 600km pipeline from the delta region oil fields (Fig. 1) (NNPC, 1984). The proposed $300 million petrochemical complex at Port Harcourt would have the capacity to manufacture, on an annual basis, 250 000 metric tons of ethylene, and 40 000 metric tons each of polyethylene chloride, vinyl chloride monomer (VCM), polyvinyl chloride (PVC) and industrialgrade methanol. It is also planned to incorporate an ammonia plant and a methyl fuel plant.

OPP VOL. 2 NO. 3, 1985

POLLUTION POTENTIAL IN NIGERIA

In addition to oil, the numerous delta region oil wells also tap large quantities of natural gas. The reserves have been estimated at 1422 billion cubic metres. At present 75% of the separated solution gases (mainly methane) from oil fields are burnt off in stacks 7m to 9m high. Extensive gas flaring has been continuous in the Niger delta area at least since 1970 (NNPC, 1984). The southern delta region also has Nigerian coal reserves estimated at over 200 million tons. In the suburbs of Enugu are four large mines from which effluent may drain into the River Niger to expose the waters to all the potential dangers of acid mine drainage. An extensive exploration and drilling of the Lake Chad basin for crude oil is currently being undertaken by the NNPC. The lake is bordered by Nigeria and the Republic of Chad and exploration for oil takes place on both sides. The semi-desert vegetation of this region may be more susceptible to damage by widespread pollution than the thick vegetation of the south coast from the development of large-scale oil industry. The major centres of crude oil production are around Warri and Port Harcourt (Fig. 1). The natural vegetation of this area is, starting from the coast, mangrove forest, freshwater swamp forest, and lowland rain forest. The soils of the area are mainly ferralitic, formed from unconsolidated younger sands with the adjusted sand/clay ratio of the upper 25 cm below 0.25. The great depth of the soil and its acid nature, due to intensive leaching, favours oil palm growth. The inland soils are bound to the south by mangrove swamp soils, which are highly saline, and by freshwater coastal swamp soils which are usually flooded (Keay, 1959). Cassava and yam are the major agricultural crops even though vegetable cultivation for urban consumption is assuming prominence. Subsistence fishing is gradually replacing the usually large-scale commercial fishing in the area because of declining productivity of the delta waters due to both faecal (Akinluyi and Odeyemi, 1984) and petrochemical (Imevbore, 1979) pollution. Nigerian main crudes are 'light and sweet' types with high API gravity and low sulphur contents. However, there are two types of classified crudes coming from the fields, namely Gulf's Escravos oil and Shell's Ughelli Quality Control Centre (UQCC) crude oil. On average, the elemental

225

composition of the crude is as follows: C = 85.92%, H = 12.86%, O = 0.83%, N = 0.07% and S = 0.19% (Oluwole and Nwachukwu, 1984); n-alkanes make up about 57%, aromatics are about 29%, and resins and asphaltanes are 14% by weight. Aromatic sulphur ranges from zero to 0.50%. The sulphur content is below the general world production average of 2.07% (Tissot and Welter, 1978). 3. CASE HISTORIES OF SOME OIL SPILLS Before the turn of the 1960s, there were probably less than 10 major blowout incidents (Ikeagwuani, 1979). However, the first major reported pollution incident from the Nigerian oil industry occurred in July 1970. Shell's Bomu-11 oil well (located in the delta region) which had been productive for 9 years suddenly blew out, impacting an estimated area of 607 hectares of land. The well was located more than 1.6 km from the nearest inhabited building but the area surrounding the location was mainly agricultural land. The Shell Company at the time recognised the need for an investigation of the effects of the spilled oil on the land and vegetation. Consequently, a five-year study project was arranged promptly and financed by the Shell Company. Odu and Udo (1975) reported, as one of their major conclusions, that recovery of the major part of the contaminated area took place after only 11/2 years. The recovery was aided by ploughing the soils to enhance aeration in favour of hydrocarbon-utilising bacteria and fungi which abound in the soils. Within the four-year period of 1976-1980, the country experienced a total of 784 reported oil spill incidents, resulting in a total loss of about 1 337 000 barrels (or 56 million American gallons) to the environment (Awobajo, 1981). About 20% of the number of spills involved incidents concerning more than 100 barrels of oil at a time. The total volume of oil spilled increased by 600% between 1978 and 1980. The majority of the spillages occurred in the swamp zones of the Niger delta, followed by offshore spills which subjected the creek and estuary waters to a large influx of oil slicks during the period. In cases that involved significant losses to water, like the Forcados terminal incident in 1979 and the Funiwa oil well blow-out (1980), chemical dis-

226

O. ODEYEMI & O. A. OGUNSEITAN

persants (mostly water- and hydrocarbon-based detergents) were used in addition to sawdust for surface absorption. In the swamp region, inaccessibility made clearing up and containment by use of floating booms essentially more difficult and over 836 acres of mangrove swamp forest suffered a major devastation (Ekekwe, 1981). In all cases, equipment failure accounted for at least 50% of annual oil pollution incidents. This included cases of burst pipelines due to high pressures and or corrosion, tank overflows, tanker loading operation, and single buoy mooring spills. The Nigerian National Petroleum Corporation (NNPC) claims that another 30% of total pollution cases were due to sabotage to wellheads and flow lines. This is a unique and rather alarming factor, considering the fact that there are over 2839 km of exposed pipelines and flowlines running across all parts of the country (Fig. 1). The remaining 20% of spills are classified under unknown causes or natural disasters (Awobajo, 1981). Most of the spillage incidents occur in the months of May and June, possibly resulting from the heavy rainfalls (usually above 320 cm annually) that characterise this period of the year which may render handling operations less efficient. During the four-year period, 43% of the total spillage incidents occurred in swamp regions while offshore incidents accounted for 21%. Another 21% was recorded for dryland and 9% for inland water (Awobajo, 1981). More recently, in February 1984, inhabitants of a densely populated neighbourhood of Lagos city complained of oil-polluted water oozing out of the many bore holes (generally regarded as water wells because of their relatively short depths) that supply the neighbourhood with domestic water. It was only after about one month of investigation that the silent source of this pollution was found out. It was discovered that one of the subterranean tanks of the Lagos oil depot at Atlas cove was leaking profusely, probably due to corrosion. The seepage must have been going on for some time to affect underground waters (Oteri, 1981). A similar case was reported in July 1984 by Kutelu at a creek town called Otujeremi in the suburbs of a Shell Petroleum Development Company oil field (Kutelu, 1984). An oil pipe leakage went undiscovered for about six days during which a substantial but yet unestimated

OPP VOL. 2 NO. 3, 1985

quantity of oil was spilled. Serious damage was done to the economic, social, and health conditions of the people of Otujeremi. For instance, marine life was paralysed and their cassava plantations became stunted. Absence of treated water forced them to drink from squalid wells which exposed them to all sorts of diseases. The three oil refineries and petrochemical plants in Nigeria continuously produce a large number of various pollutants especially within their industrial effluent wastes. These pollutants from the refineries at Port Harcourt, Warri and Kaduna are usually disposed (after some treatment) into bodies of water, where they may produce detectable odour, taste and colour at very low concentrations. Some pollutants can cause edible fish to acquire an unpleasant taste (Anon., 1970). There are, as yet, no exact data on the chemical nature of effluents from the Nigerian refineries. There is a need, therefore, for proper monitoring and treatment of refinery wastes prior to discharge into waterways. 4. POLLUTION EFFECTS Agricultural practice is usually inhibited by the activities of the oil companies during their exploring and drilling for oil. In Nigeria, the scanty land areas that characterise the delta regions are made unavailable even for normal agriculture. Apart from large spillages, the oil drilling wastes, which include drilling muds and salt water brines pumped out of the wells' crude oil, usually pollute both aquatic and terrestrial eco-systems. When the occasional massive oil spills do occur, affected soils are rendered temporarily sterile as microbial forms are seriously inhibited. Impairment of important soil biochemical processes such as organic matter decomposition, ammonification, nitrification, symbiotic and non-symbiotic nitrogen fixation and the geochemical cycling of elements is likely to occur, thereby rendering such soils agriculturally unproductive. Crude oil pollution in the delta region has been found to inhibit germination of seeds of Zea mays and Capsicum frutescens. Crude oil also acts as a potent contact herbicide on these two plants and on Abelmoschus esculentus (Amakiri and Onofeghara, 1983). The effect of gas flares on the surrounding vegetation has also been considered fully by Isichei and Sanford (1976).

OPP VOL. 2 NO. 3, 1985

POLLUTION POTENTIAL IN NIGERIA

Human habitation of the areas adjacent to oil fields, depots and filling stations may be imperilled by the operations of the oil companies in the country. The Funiwa oil well blow-out which occurred in January 1980 (involving about 200 000 barrels of crude oil) deprived the inhabitants of the affected area of access to potable water. It is pertinent to note here that treated pipe-borne water is a scarce commodity in these areas, and the community, usually including employees of the oil companies, depends on bore holes and flowing streams for their supplies. The inhabitants were also deprived of their fishing occupation, resulting in a massive displacement of thousands of farmers and fishermen. Medical doctors and dispensers in the area reported a prompt increase in the incidences of vaginitis, gastroenteritis, conjunctivitis, dermatitis and vulvitis among the people (Anon., 1980). There were obviously numerous, but less prominent, ecological effects of the Funiwa oil spill on the biotic components of the coastline. Apart from some natural portions of petroleum such as lubricating oil, asphalts and waxes which are resistant to microbial degradation, there are hundreds of other synthetic polymers produced from the petrochemical industries that are biologically resistant. Such inert synthetic products, which include nylon, Dacron, Teflon, polyethylene, polystyrene and polyvinyl chloride, are at present gaining prominence for packaging, insulation, household carpeting, and as fabrics for clothing. Less than a decade ago, these products had to be imported into Nigeria and as such were not common waste products and the spent products merely constituted nuisances and aesthetic problems in the environment. With the recent development of the petrochemical plants, these resistant synthetic products are gaining in use and are rapidly replacing traditional materials that were usually less resistant to microbial degradation. Thus, in present-day Nigeria, plastic and polyethylene materials litter the streets and highways because they are not readily susceptible to microbial degradation. The disposal of waste oil is another problem emanating from the Nigerian oil industry. For instance, factories, private workshops and numerous motor service stations all over the country make use of petroleum and petrochemical products. Quite often, their spent oil products are

227

dumped carelessly and indiscriminately. These spent oils accumulate and the pollutions invariably spread through public drains to nearby rivers and streams where they may constitute public health hazards.

5. REGULATIONS It is pertinent to note that Nigerian statutes on oil and petrochemical pollution control are usually enacted piecemeal as pollution problems, especially those resulting in devastating consequences, arise. For instance, as a result of pollution resulting from spillages of oil from pipelines tampered with by thieves and saboteurs, the Federal Military Government recently promulgated a decree called the Special Tribunal (Miscellaneous Offences) Decree 20 1984. The decree prescribes a death sentence on a person or a group of persons convicted of bunkering activities and tampering with oil pipelines. It should be realised that the cause of these nefarious activities may be deep rooted. For instance, these acts of sabotage may be a manner of registering protests and seeking redress by some sections of the community with regard to the spread of development and the social benefits therefrom. Deliberate damage to oil pipelines to induce pollution may also be due to a speculation, in the riverine oilproducing areas, that the compensation obtained from oil companies (that will invariably be accused of causing the spillage) constitutes a panacea for pecuniary requirements of the people of the affected area. Yet there are some aspects of the oil operations that have no regulatory legislation. For instance, there are no regulations at present, either from the Petroleum Inspectorate or the Federal Ministry of Housing and Environment, to safeguard the people who live close to oil filling and service stations where large underground storage tanks are installed, sometimes close to bore holes used for drinking and other domestic activities. In addition to the hazards of fire incidents, unseen pollution by seepages from the underground tanks and from openly disposed waste oil are threatening areas close to oil storage and service depots. Nigeria has provisions in a number of statutes designed to prohibit or control the pollution of

228

O. ODEYEMI & O. A. OGUNSEITAN

water, air, and land, which prescribe sanctions to be enforced against persons or companies who infringe the provisions. However, it is regrettable that the provisions are not captioned as environmental laws and as such do not cover all types of environmental pollution. The statutory provisions are couched in general terms, with few or no regulations made to detail the proper application of the statutes. It has been suggested that any enactment to control oil pollution should be considered in the context of other forms of pollution and damage to the environment (Olisa, 1981). Hitherto, Nigerian laws on oil and petrochemical pollution control, which are found scattered in the statute books, have been mixed and diffusive. There is an urgent need for an all-encompassing re-evaluation of the existing social, economic, ecological, and regulatory conditions under which the Nigerian petroleum industry functions, to collect the laws into a specific and comprehensive environmental law of international standards. In this regard it will be useful to borrow a leaf from other oil-producing countries who have enacted various laws to deal with their oil and petrochemical pollution problems. For instance, in the United Kingdom there are statutes such as Petroleum (Road Transportation and Storage Regulations) Act 1928, Inflammable Substances (Conveyance by Road and Labelling) Regulations 1971, Petroleum Spirit Regulations 1966, Deposit of Poisonous Wastes Act 1972, Pipelines Act 1962, and Petroleum and Submarine Pipelines Act 1975, to deal with various aspects of oil and petrochemical pollution (Wardley-Smith, 1979). Apart from the requirement for legislation, the

OPP VOL. 2 NO. 3, 1985

NNPC should closely monitor the operations of the different oil companies in the country. However, the NNPC may find it difficult to carry out such an assignment effectively since their own plants and installations are some of the sources of pollution. It is also doubtful if the Inspectorate Division of the NNPC can perform efficient monitoring operations. Therefore, there is a need to establish a body of completely independent inspectors, who must ensure that the oil companies comply with the government's directives and legislation on oil prospecting, drilling, mining, spillage, refining, transportation, and storage. For instance, oilrefining companies must be compelled to treat oil refinery wastes to remove dangerous pollutants prior to the disposal of such wastes into bodies of water. The inspectors should also ensure that appropriate legal sanctions are imposed on all who break the laws. Finally, the NNPC ought to commission general environmental impact studies, dealing wire the impact of the oil industry on society and the environment. These should include studies on the economics of pollution, risk analysis, contingency plans, cost of safety, as well as the sociological and legal consequences of major spills. The NNPC should also initiate pollution and damage assessment studies as a means of rapid estimation of damages that would result from oil pollution of arable farms, terrestrial and marine environments by spillages, blow-outs, and pipeline leakages. A broad educational campaign for residents in the immediate vicinity of oil industries, and those who work directly with the products all over the country should also be undertaken.

REFERENCES Akinluyi, T. O. and Odeyemi, O. 1984. Human waste disposal and the faecal pollution of the Niger delta waters. Water International 9, 37-41. Amakiri, J. O. and Onofeghara, F. A. 1983. Effect of crude oil pollution on the growth of Zea mays, Abelmoschus esculentus and Capsicum frutescens. Oil & Petrochemical Pollution 1 (3), 199-205. Ainu, L. 1982. A Review of Nigeria's Oil Industry, Public Affairs Department, Nigerian National Petroleum Corporation, 32 pp. Anon. 1970 Petrochemical effluents treatments practices. Water Pollution Control Research Series, Program No. 12020, Robert S. Kerr Water Research Center, Ada, Oklahoma. Anon. 1980. Newspaper report in The Punch, March 1st, Lagos, Nigeria. Awobajo, S. A. 1981. An analysis of oil spill incidents in Nigeria. The Petroleum Industry and the Nigerian Environment, Proceedings of 1981 International Seminar, NNPC, Lagos, Nigeria, pp. 57-63. Ekekwe, E. 1981. The Funiwa-5 Oil well blowout. The Petroleum Industry and the Nigerian Environment, Proceedings of 1981 International Seminar, NNPC, Lagos, Nigeria, pp. 64-68.

OPP VOL. 2 NO. 3, 1 9 8 5

POLLUTION POTENTIAL IN NIGERIA

229

Hodges, L. 1977. Environmental Pollution, 2nd edn. Holt, Rinehart, and Winston, New York. Ikeagwuani, F. O. 1979. Trends of petroleum exploration in Nigeria. Nigerian National Petroleum Corporation report, 50 pp. Imevbore, A. M. A. 1979. The impact of oil production on the biota of the Niger Delta. Seminar on the Environmental Aspects of Oil Pollution in the Niger Delta, Port Harcourt, Nigeria, 30 pp. Isichei, A. O. and Sanford, W. W. 1976. The effects of waste gas flares on the surrounding vegetation in south eastern Nigeria. J. Appl. EcoL 13, 177-187. Keay, A. W. L. 1959. An Outline of Nigerian Vegetation, 3rd edn, Federal Government Printer, Lagos, Nigeria. Kutelu, J. 1984. Otuyeremi-- A creek town where water is essential commodity. The Punch, September 17th, Lagos, Nigeria. NNPC 1982. Facts about the Nigerian National Petroleum Corporation, NNPC, 1977-1982, Lagos, Nigeria, 39 PP. NNPC 1984. Monthly Petroleum Information, September. Nigerian National Petroleum Corporation, Lagos, Nigeria, 53 pp. Odu, C. T. I. and Udo, E. J. 1975. 'Getting Back to Normal', A report on the research and rehabilitation of Bomu-11 blowout. Shell Petroleum Development Company of Nigeria Ltd, Lagos, Nigeria, 72 pp. Olisa, M. M. 1981. Legal framework for pollution control in the petroleum industry. The Petroleum Industry and the Nigerian Environment, Proceedings of 1981 International Seminar, NNPC, Lagos, Nigeria, pp. 37-42. Oluwole, P. A. and Nwachukwu, J. I. 1984. Chemical composition of bitumen extracts from Nigerian tar sands. Energy Sources (in press). Oteri, A. U. 1981. A study of the effects of oil spills on ground water. The Petroleum Industry and the Nigerian Environment, Proceedings of 1981 International Seminar, NNPC, Lagos, Nigeria, pp. 89-94. Tissot, A. W. and Welter, M. 1978. Petroleum Formation and Occurrence, Springer Verlag, New York. Wardley-Smith, J. (Editor). 1979. The Prevention of Oil Pollution, Graham & Trotman, London, 1979.