Shell Expro unveils spar disposal plans

Jan. 20, 1997
Short list of Brent Spar Disposal Options [.pdf format] Shell U.K. Exploration & Production has disclosed a short list of six contractors chosen to develop detailed plans for disposal of the derelict Brent spar oil storage buoy. The spar was used to store oil in U.K. North Sea Brent field before export pipelines were installed. Efforts to dump the buoy off Northwest Britain were halted by an international protest in 1995 (OGJ, June 26, 1995, p. 21).
Shell U.K. Exploration & Production has disclosed a short list of six contractors chosen to develop detailed plans for disposal of the derelict Brent spar oil storage buoy.

The spar was used to store oil in U.K. North Sea Brent field before export pipelines were installed. Efforts to dump the buoy off Northwest Britain were halted by an international protest in 1995 (OGJ, June 26, 1995, p. 21).

In mid-1996, Shell Expro, the operating joint venture of Shell U.K. Ltd. and Esso Exploration & Production U.K. Ltd., asked 19 contractors to provide 30 outline disposal plans (OGJ, Aug. 19, 1996, p. 39).

From these, Shell Expro has selected 11 ideas proposed by six contractors or groups. Eric Faulds, Shell Expro decommissioning manager, said the company will pay the contractors a total £1.5 million ($2.4 million) to fully develop these proposals.

Faulds said contractors must submit their detailed proposals by Apr. 30. Shell Expro will review the proposals, a process expected to take 3 months, then recommend a disposal plan to the U.K. government.

"We expect to make a recommendation to government this year," said Faulds, "with a view to disposal of the spar in spring next year."

Short list proposals

Faulds said the shortlisted proposals featured two techniques to help raise the spar from the water: pumping the hull full of compressed gas to prevent its walls collapsing during maneuvering; and building a lifting cradle around the spar, connected by cables to jacks on barges moored alongside.

Shortlisted ideas for what to do with the spar once it has been dismantled can be split into three types, said Faulds: re-use, recycling, and disposal.

Shortlisted contractors and their proposals (see artist's renderings, p. 25) are:

  • Brown & Root Energy Services suggests raising and rotating the spar into a horizontal position using compressed gas, for dismantling and scrapping onshore.

  • Kvaerner Stolt Seaway Alliance proposes using compressed gas either to raise and rotate the spar to horizontal or raise it vertically and then either scrap it onshore or: use topsides as a training center; use the hull as a dock gate; use the hull sections as a fish farm; or use the hull as a quay extension.

  • McAlpine Doris JV suggests raising and rotating the spar using compressed gas and using the hull as a quay extension.

  • Thyssen Stahlunion GmbH and Aker AS propose raising the spar vertically using a jacked cable lift and scrapping it onshore.

  • Wood-GMC proposes raising the spar vertically using a jacked cable lift, then using topsides as a training center and the hull as a quay extension.

  • AMEC Process & Energy suggests using hull sections as coastal protection.

Faulds said a single contractor may not be awarded the whole disposal contract, because AMEC's idea for raising the spar from the water did not make the short list.

The dock gate and fish farm proposals by Kvaerner Stolt Seaway were said to have been submitted after the original long list had been drawn up. Most of the quay and harbor disposal schemes are projects that are going ahead in any event.

Disposal costs

Faulds said cost estimates were not requested as part of the outline proposals but will be included among the criteria for choosing which plan to recommend to government.

Shell Expro had spent £10 million ($16 million) up to the point where the Brent spar dumping program was aborted. The company expects to have spent a further £9 million ($14.4 million) by the time the final contract is let.

Faulds said Shell Expro is paying the Norwegian government £20,000 ($32,000)/month to moor the derelict buoy in Erfjord, near Stavanger.

It has permission to moor the spar until July and will apply for permission to keep it there for another year.

Heinz Rothermund, managing director of Shell Expro, said, "This is not a race; we want to get it right. Our focus is on efforts to find a solution which is on balance better than deep sea disposal, which remains a benchmark, before we make a recommendation to government."

Copyright 1997 Oil & Gas Journal. All Rights Reserved.