For an undeniable fact, exploitation of petroleum resources has sumptuous economic implications for a country, as well as in most countries has also reduced enormously natural oil pollution from oil seeps. However, activities of oil companies as perceived by the environmentalist have serious, unplayful impacts on the environment. Research done by a group of scientists from the Ambrose Alli University of Nigeria on “The effects of petroleum exploration and production operations on the heavy metals contents of soil and groundwater in the Niger Delta” shows a high pollution of the groundwater systems and soils. The heavy metals investigated including, Iron, Copper, Cadmium, Chromium, Lead and Nickel and their existence in extreme concentration in water and food and subsequent consumption poses serious health problems and damage to internal organs. For example, excess consumption of lead can lead to plubism, and damage the brain, Central Nervous System, kidney, liver and the reproductive system. In this article, cardinal activities in upstream operations including seismic, drilling, development and production, and transportation shall be scrutinized in the light of their environmental impacts.
Although there has been a lack of scientific evidence on the detrimental effect of acoustic waves on marine life, the geophysical industry has not been able to prove this. There are serious concerns on the effects of seismic waves on whales, sea turtles, prawns, lobsters, and other commercial fish species. In the Gulf of Mexico, United Kingdom, Canada, Australia and most part of the world it is a standard procedure that a seismic contractor performs ramp-up procedure to warn sea animals and make provision for 24 hour observer crews onboard seismic vessel to observes the presence of sea animals that likely to be harmed by acoustic waves. Ramp-up procedure drives sea animal at least about 500 meters from a seismic array. Research conducted in the Norwegian seas has proven that seismic shooting could cause fish to travel tens of kilometers, and some may not return unless after a few weeks. In onshore data acquisition, vast area of vegetation needs to be cleared to improve accessibility to Vibroesis and other seismic acquisition equipment. The destruction to vegetation is made more pronounced in mangroves and forests.
The predominant discharges during drilling are cuttings; small chips of formation rock cut by the drilling bit and the mud used in cooling and lubricating the drilling bit, carry the cuttings out of the hole and counter-balance the pressure of gas when it is reached. It is generally accepted that drill mud cause greatest harm in exploration activities. In an experiment to monitor the damage caused by drill mud in an exploration drilling in 1981-82 on Georges Bank, barium, a tracer of drilling mud doubled in concentration 35 km eastward and increased six fold 65 km in the western direction. Oil based muds have been known to have detrimental effects on benthic organisms because of it redox potential.
Development and Production
The development stage is characterized by further drilling and installation of pumps, and separation equipment together with their peripherals. Directional drilling where several wells can be drilled from a single platform has reduced the amount of “footprint” and subsequent contamination of soil and destruction of vegetation in onshore and offshore expeditions.
In countries where there is no commercial market for associated gas, the gas is flared. The World Resources Institute Report World Resources 1994-95 indicates that total gas flaring in 1991 produced a contribution of 256 million tones of Carbon Dioxide emissions which represent some 1 per cent of global carbon dioxide emissions (22, 672 million tones).
Particulates which are generated from other burning sources such as well testing contribute enormously to atmospheric pollution. Apart from the emission of carbon dioxide and carbon monoxide, nitrogen oxides and hydrogen sulphide gases are introduced into the atmosphere; the quantity of which depends on the content of nitrogen and sulphur in the oil.
In production, the major waste is produced water containing inorganic salts, heavy metals, solids, production chemicals, hydrocarbons and occasionally Naturally Occurring Radioactive Material (NORM); these have minimal effect on the environment. Nonetheless the release of produced water into freshwater bodies requires special care. Transportation Oil transportation has been a major source of pollution through oil spills and leakages. Oil spills occur as a result of unguaranteed mechanical processes that are involved in oil transportation. For a period of fourteen years, from 1986 to 2000, the Nigerian petroleum industry suffered a total of 3,854 oil spills squirting a total of 437,810 barrels of oil into the Nigerian environment. Oil spills have been known since antiquity and they appear to be inevitable in oil production.
Pipeline installation requires massive dredging of seabed and excavations of soil, which poses serious threat to sensitive environments. In onshore areas, estuaries, wet land and mangroves are disturbed massively and may result in flooding. Offshore activities are associated with dredging of seabed and destruction marine habitat.
Human, Socio-economic and Cultural Impacts
There are serious concerns on land use and fishing in the Western shores of the country. Until recently, exploration activities and fishing have not existed peacefully in this part of the country. With the influx of skilled and unskilled labor into the Western Region, it is highly anticipated that local population levels are going to surge together with diverse unfamiliar cultures. Sociologist would be interested on the impact of diverse cultures on the fragile Ghanaian culture.
Socio-economic imbalance would be created due to new employment opportunities, income differentials, inflation, differences in per capita income when different members of local groups benefit unevenly from induced economic changes. Autochthonous people often react when they are persuaded the activities of oil companies are detrimental to their social economic and physical wellbeing, as it has been the modus operandi in the oil prolific Niger Delta region. In some cases oil pipelines are vandalized by local people as in their opinion, they want to take their share of the national oil cake. The end results of which have been mostly fatal.
By June, 10th 2006, a total of $ 400 billion has accrued from Nigeria’s 50 years of oil and gas exploration and production, yet there are millions of Nigerians wallowing in extreme poverty. This has a major incentive to the concerns being raised about the possible repetition of the “paradox of plenty” on the Ghanaian side of the oil industry.
A barrel of oil is pumped along several barrels of environmental issues. Would we as a nation forfeit exploiting our natural resources with the primary intention of developing the nation because of the associated environmental issues? Certainly no; hence environmental pollution is inevitable. There are several international conventions on the conduct of Exploration and Production (E&P) companies. However, depending on the political environment, and as a means of maximizing profit, oil companies would relinquish their environmental responsibilities. It therefore becomes imperative on governmental and non-governmental watchdogs to monitor the activities of E&P companies. At this juncture, the Ghana National Petroleum Corporation (GNPC)—the Lord of petroleum exploration and production activities in Ghana, the Ministry of Environment and Science, the Environmental Protection Agency and the Ministry of Energy should be commended for the indomitable, synergetic work they have done supervising the exploration and development stage of the Jubilee Field. We trust them that during the production stage, the environmental laws would be strictly enforced to ensure a safer environment both in the short and long terms.
I dedicate this article to my Father, Mr. Phillip Sam and my Mother Ms. Gifty Amoakwah for pushing on the ladder of education to this epitome. I am grateful. I love you.
Eugene Sam-Okyere Department of Geological Engineering KNUST, Kumasi. [Email: ugsam2000]