Piper Alpha (Hansard, 8 December 1988)

§ Mr. Peter Morrison

As I told the House on 30 November at column 757, my right hon. Friend the Secretary of State had, that morning decided that subject to conditions, he was prepared to approve, under section 4 of the Petroleum Act 1987, the abandonment programme for Piper Alpha submitted by Occidental and its co-venturers. This proposed the use of explosive charges to topple the remains of the installation outwards on to the sea bed, away from the existing pile of debris, leaving at least 75m of clear water above all remains.

I also explained that the co-venturers had the right under the Petroleum Act to make written representations about the proposed conditions. They have now informed my right hon. Friend that they do not wish to make representations and he has approved their programme.

The conditions attached to my right hon. Friend's approval include requirements for surveys of the toppled remains and surrounding sea bed to establish the position of debris and to monitor for leakage of oil or gas. They also require sediment samples to be obtained and examined for the presence of polychlorinated biphenyls (PCBs) and radioactivity. The conditions provide for repetition of these surveys and of sediment sampling at such times as the Secretary of State may subsequently direct. They also provide for debris to be moved or removed as he may direct, for any leakage of oil or gas to be sealed to his satisfaction and for steps to be taken to deal with any unacceptable levels of pollution.

The installation was so badly damaged by the fire and explosions of 6 July as to be beyond preservation. If it is not toppled in a controlled way its collapse is inevitable, and could occur soon but probably during the coming winter. If it does collapse under natural forces, it is likely to fall inwards upon existing debris rendering any further removal or recovery operations impossibly difficult and dangerous and creating a serious hazard to shipping, as it would lie just below the surface.

To take the platform down piece by piece would mean first removing the remaining module. Because of the precarious condition of the module itself, and of the structure supporting it, Occidental and its co-venturers submitted, and the Department's safety directorate accepts, that such an attempt would involve unacceptable hazard to the personnel involved.

The possibility that a toppling operation might destroy evidence which would otherwise assist the technical investigation or the public inquiry has been carefully considered also. However, the visible remains have been 334W inspected and it seems unlikely that any useful evidence would be lost. The toppled structure in its final position should not make access to the central debris pile, and such evidence as it may contain, any more difficult than is already the case. Toppling the jacket would however eliminate a hazard which could otherwise hamper diving and other work on the existing debris. Both Lord Cullen and the Procurator Fiscal, have been advised of Occidental's proposal, and neither has any objection in principle.