Page:Niger Delta Ecosystems- the ERA Handbook, 1998.djvu/187

Environmental Impact of the Oil Industry farmland, leap streams and intrude into villages. Ironically where the flowlines leap a stream they can be used as a precarious foot-bridge, but an abiding impression of the Niger Delta countryside is of women farmers head-loading produce back to the village after a day's farming and negotiating the flowlines with an elegant skill. They take land away where they run across farmland. They involve the clearing of vegetation and thus damage ecosystems where they run across forests. And, here it must be appreciated that the impact upon ecosystems goes beyond the actual area cleared. For instance, not only may access be enabled to areas otherwise relatively inaccessible, but also, forest temperature, light and moisture conditions will be altered on either side of the line. They are badly maintained. Pipelines burst from time to time spreading crude oil over large areas. Flowlines generally leak because they are not replaced on schedule, and also burst, sending out fountains of emulsified oil and gas because they are under pressure.

The potential danger is increased because pipe and flowlines intrude into villages. Oddly, the oil companies maintain that originally pipelines and flow lines are initially sited away from settlements, as if, over forty years, the expansion of settlement areas was not anticipated.

15.5.4 TERMINALS

The main environmental impact at the terminals is the continuous discharge of large volumes of water with low oil concentrations of oil. Concentrations in the magnitude of 7 ppm according to the SPDC fact book off 1993.

15.5.5 REFINERIES

The refineries at Warri and Port Harcourt are both badly maintained. The World Bank report of 1995 suggests that better maintenance would reduce their polluting habits. The refining process produces a hazardous sludge. In Warri this is deposited in a neighbouring swamp. In Port Harcourt it is dumped into the Bonny River.

According to the World Bank report, the refinery in Port Harcourt generates all the NOx (Nitrogen oxides) emissions in the city and 25% of the industrial particulate emissions. In Warri, metal concentrations in soil were found to be elevated above the background as follows: 185