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February 2002

Article

 

Indigenous Plants to the Rescue
 Environmental remediation in Nigerian oil regions

 

More than four decades of oil exploration and production activities have left a severely degraded environment in Nigeria's southern, Niger Delta oil region.

Spills - the uncontrolled discharge of oil or its by-products including chemicals and wastes, which mainly occurs through equipment failure, operational errors, or wilful damage - have been identified as the main source of environmental damage in the region over time.

But adverse impacts on the ecology have also resulted from oil drilling; the dredging of the swamp waters by oil multinationals for access to pipelines and facilities; and natural gas flares that occur in the course of oil production.

After many years, during which these adverse effects either received scant attention or were simply ignored, fresh efforts have been mounted in recent years by both environmentalist non-governmental organisations (NGOs) and oil multinationals to remedy the situation.

The Centre for Environmental Resources and Sustainable Ecosystems (CERASE) a Nigerian NGO is spearheading a unique programme, with the backing of the World Bank, which aims at improving the capacity of local people in the Niger Delta to launch bio-remediation efforts without waiting for government intervention.

A pilot project started by the group at Ogbogu, a community in one of the largest oil producing areas of Ogba/Egbema/Ndoni local council of Rivers State, uses plants and micro-organisms to clean up oil spills from the environment, particularly those affecting farmlands and fishing areas.

"The concept of biological remediation being proposed by CERASE does not only cover microbial treatment, but also the direct use of other natural resources to combat degradation by involving the people in a participatory development approach," Uzo Egbuche, the group's executive director, told IRIN.

"The advantage this method has is that involves rural people in a programme to protect their lands and provide them economic opportunities, thereby reducing cases of civil unrest due to frustration over ecological degradation," she added.

Essentially two plants, kenaf (Hibiscus Cannabinus) and vetiver (Vetivera Zizanioides), are being used in the project. Kenaf, an annual herbaceous plant, indigenous to West Africa, apart from use in production of pulp and paper products, has proved very effective as an oil absorbent in cleaning oil spills. In experiments carried out by CERASE, dried pulp made from kenaf was flattened into sheets and placed over oil spills which they readily soaked up.

The soaked up bags were then taken to special clean up sites where they were subjected to microbial breakdown. Several microbes have been identified that are capable of naturally breaking down a large variety of hydrocarbons.

The vetiver plant is then applied in the next stage. A perennial which requires very little maintenance, its extensive, fibrous root system binds the soil to a depth of three metres. Apart from a high chemical tolerance, it has the capacity to decontaminate soils of harmful chemicals. "CERASE intends to use vetiver grass for biological remediation and soil stabilisation in order to control and arrest soil degradation," Egbuche said.

To make the programme sustainable, CERASE is encouraging local people to create nurseries for kenaf and vetiver. According to Egbuche, this has already become an income generating activity in the project community. When the project is replicated in other communities in the oil region, it is hoped that an important economic activity will have been set in motion whereby commercial operators will provide seedlings and processed kenaf absorbents to oil companies. In this respect, the organisation is collaborating with Living Earth Nigeria Foundation, an environment NGO which specialises in participatory community development.

However, the task of battling the effects of environmental pollution due to oil spills in the Niger delta is huge, as studies conducted by Alex Chindah and Solomon Braide of the Institute of Pollution Studies, Rivers State University of Science and Technology, Port Harcourt, show. Over a 20-year period spanning 1976 and 1996, an average of 300 cases of oil spills per year were recorded in Nigeria's oil region. On the average, some 370,000 barrels of crude spilled into the environment each year, out of which only about 40 percent was recovered.

"The environmental effect of spilled oil is a function of time, type of oil spilled, its degree of weathering, the sedimentary characteristics of the receiving environment and the season of the year," said Chindah at a recent workshop. The immediate impact on vegetation are wilting, defoliation and loss of the productive cycle or outright death of affected plants.

On freshwater swamps, the studies showed, the effects are more devastating due to the longer water retention time. Lower plant forms, such as algae and lichens die off immediately. Animals, fish and other water organisms dependent on such ecosystems also die off sooner or later. In turn the communities in the affected areas suffer loss of livelihoods, poor health and other adverse consequences.

To help deal with the huge environmental damage caused by oil spills, Shell, (the biggest operator in Nigeria which has most of its operations onshore and is, therefore, responsible for most of the spills) has evolved a scheme whereby communities are involved in the remediation efforts. Participating communities are required to nominate people who are trained as "Remediation Technicians". This, the company says on its web site  www.shellnigeria.com, has proved an effective way of implementing the less complex remedial actions.

To improve coordination of its own remedial efforts, Shell had by the end of 2000, conducted an assessment of 786 operational sites (700 on land and 86 in swamp areas), with 424 sites still due for assessment. "Of the sites assessed, 219 have been identified as requiring remedial action," the company says. "To date, some 55 sites in 15 fields have been returned to environmentally acceptable conditions since the inception of the programme."

According to Egbuche, CERASE has opened communication with the oil companies in Nigeria on how their community participatory approach could be incorporated in the industry's oil spill response plans. "The philosophy behind this concept was the promotion of integrated environmental conservation and rural development buttressed by community participation," she told IRIN. "It is envisaged that this highly sustainable rural development approach will create multiple avenues for poverty alleviation." 

More Information

IRIN-WA Tel: +225 22-40-4440 Fax: +225 22-41-9339 Email: IRIN-WA@irin.ci This Item is Delivered to the "Africa-English" Service of the UN's IRIN humanitarian information unit, but may not necessarily reflect the views of the United Nations. 







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