I thank the noble Lord for the invitation, but I am chairman of the preservation society of the old London fire boat, the “Massey Shaw”, which is another Dunkirk veteran, so I may be committed already.
As we have heard, this wreck is surveyed constantly, at least once or twice a year. It was last done in February and March of this year, and another survey is due in August. Huge improvements in the efficiency of side-scanning sonar have meant that surveys can usually be accomplished in just two days—compared with many days, with weather hold-ups, in the past—and we can now measure very accurately any changes in the deterioration of the wreck, even down to centimetres.
The noble Lord mentioned the possibility of some of the bombs having spilled out of the ship. If they had done, they would have been quickly picked up by the new sonar, and there is no evidence that I can see that that has happened. In addition, a remote sensing tripod has been placed on the sea floor to measure any environmental changes—the noble Lord, Lord Patten, referred to this—including changes to the seabed, which is constantly scoured by the tide coming out of the River Medway.
The Maritime and Coastguard Agency, which is the official Receiver of Wreck in inshore waters, engages an internationally recognised survey company to carry out the work. It either uses one of its own vessels or, if that is not available, it takes one of the Port of London Authority’s well-equipped survey vessels, which have the added advantages of knowing the waters and being more or less on the spot, as they are based in Gravesend. I understand that a technical adviser from the MoD is on board at all times during the surveys.
I also understand that the Department for Transport has set up an expert advisory panel which initially met every two months but now, I gather, tends to meet whenever new evidence comes to light.
Sheerness is no stranger to explosions. On
I now continue with the history lesson and turn to two subsequent ship explosions, which may have some relevance in terms of a worst-case scenario. On
The second explosion concerned the “Fort Stikine”, another emergency war-built vessel, but not a Liberty ship—she was a Fort built in Canada. She had a part-cargo of 1,400 tons of explosives. When she blew up, it destroyed a large part of the dock area in Bombay in two separate blasts on
I have mentioned these examples to indicate what can happen when an ammunition ship explodes, but in three of the examples I have given, heat was the ultimate cause of the blasts. In HMS “Bulwark”, explosives were being stored temporarily too close to a boiler room, and the “Fort Stikine” had developed a fire in her part-cargo of cotton bales, which were stowed beneath the ammunition. In addition, the Halifax and Bombay explosions occurred literally within their respective cities, which multiplied the damage.
Compared with these, the “Richard Montgomery” wreck is situated 1.5 miles off Sheerness and five miles from Southend, and the munitions remaining on board have now been submerged for 75 years, as the noble Lord, Lord Harris, said. A former bomb disposal expert who advised the Government on the cargo of the “Richard Montgomery” has said that water is a good mitigator in preventing detonations.
There are, of course, worries about Sheerness and the LNG terminal and storage facilities on the opposite bank on the Isle of Grain. The new storage tanks have nickel-something—I cannot remember the name—inside, with pre-stressed concrete outside and a reinforced concrete roof. They are a bit like a German bunker in many ways, so I am not certain that they would be too badly affected. However, I know that only a few weeks ago a new rail service started up to carry aviation fuel from there to Heathrow.
Some people have proposed either moving the whole wreck, which would be well-nigh impossible, or just removing the munitions. The latter course has been estimated to cost tens of millions of pounds and would probably involve the evacuation of Sheerness.
On balance and in conclusion, I tend to follow the line of the noble Lord, Lord Patten, that we should leave well alone but continue to monitor closely the gradual degradation of the wreck.