Controversial Brent Spar Disposal Coasts Soar

Shell U.K. Exploration and Production said the final cost of a four-year project to decommission its controversial Brent Spar oil buoy had risen sharply. At a feedback seminar marking the effective completion of Brent Spar's conversion into a quay on the Norwegian coast, Shell officials also said instead of resulting in a projected net gain in energy the project had resulted in a net energy deficit. "Throughout the dismantling process we were faced with unexpected technical, safety and environmental challenges which had to be overcome and each one cost time and money," Eric Faulds, decommissioning manager for Shell's exploration and production arm Shell Expro said. Dismantling costs had increased to $25 million from an original estimate of $13.4 for the rig, which is being converted into a quay at Mekjarvik, near Stavanger. A further $11.8 had already been spent in the summer of 1995 on an original project aimed at disposing of Brent Spar in the U.K. waters of the North Sea. Shell Expro, the U.K. operator for Royal Dutch/Shell and Exxon in Britain, was forced to abandon deepwater disposal after a public outcry led by environmental campaigners Greenpeace. Faulds said final disposal was now effectively complete after Spar was cut into ring sections and cleaned by contractor Wood-GMC before being placed on the seabed at Mekjarvik as the base of a new quay. The project took 330,000 man hours to complete and resulted in no injury to personnel. There was also no sea pollution resulting from the dismantling operation, Faulds said. Shell said the content of Spar's tanks had proved well within the accuracy requirements for an environmental impact assessment set by Det Norske Veritas (DNV) when it carried out an inventory check for Shell in 1995. The weight of oil was found to be 150 tons, compared with a Greenpeace estimate of 5,500 tons. Faulds said the objective of generating a positive energy balance from reusing the Spar ring sections and recycling the topsides and transition columns had not been achieved. "The Wood-GLC proposal was the only means of disposal which promised a net gain in energy," said Faulds. "We were able to count every drop of diesel used and unfortunately, we didn't get the positive energy benefit hoped for." He said the original projection, which took into account the energy saving from not having to construct the jetty at Mekjarvik from scratch and from recycling oil and wax residues for heat generation, envisaged a net gain in energy of 48,400 gigajoules of energy. Instead there was a net loss of 115,000 gigajoules, equivalent to the energy needed to heat around 6,000 homes in the Scottish town of Aberdeen for one year, Faulds said. This is over twice the net energy loss of 52,100 gigajoules envisaged in a study by DNV into deep sea disposal. "Scientifically, deep sea disposal was the best option," Faulds said. "But sound science and regulatory compliance are not enough, we must listen to stakeholders. This is now our company culture."