I am not aware of whether an assessment has been made but I will write to the noble Lord to confirm on that point. The noble Lord, Lord Greenway, mentioned the establishment of the expert advisory group to help us to consider how best to manage the wreck in future. This was formed in November 2017 and is made up of an independent chair, experts from the salvage industry and various government experts with knowledge of dealing with wrecks or experience of dealing with munitions of the type contained in the wreck.
An important function of the group is to provide a steer of potential options for long-term management of the wreck. The group is currently considering whether monitoring and regular surveying is still the correct course of action or whether a more proactive intervention should be considered. As the noble Lord, Lord Berkeley, suggested, interventions could include the removal of munitions or some form of containment of the wreck, as the noble Lord, Lord Addington, mentioned. I stress that the advice I have been given is that this is not as straightforward as the noble Lord perhaps suggested.
On the decision-making responsibility, any decision about a change of approach to the wreck would be made by Ministers. We appreciate that there are no risk-free options, as noble Lords have pointed out, which is why we are using the most qualified experts we can find.
The noble Lords, Lord Harris and Lord Addington, asked about contingency planning in the event of an incident. Responsibility lies with the Kent Resilience Forum, which includes all the first-response services. It is kept closely updated about the results of the survey and has wider plans for the safety of the area, of which any incident with the wreck obviously forms a key part.
The noble Lord, Lord Harris, asked about a tidal wave that might travel up the River Thames in the event of a detonation. We do not believe that would be the outcome. Rather, we believe there would be a sudden displacement and replacement of water, which would impact the immediate vicinity but would not form a travelling wave.
The noble Lord also asked about incidents and incursions. We have talked about the paddle-boarder and the Chinese fishing boat in 2002. We believe that the 2012 security operation was precautionary. I have no record of other incidents.
With regard to conversations with the US Government, the department is not sure why any offer of help was rejected. The issue has not been discussed recently and responsibility sits clearly with this Government.
To conclude, I again thank the noble Lord, Lord Harris, for bringing this debate on such an important issue and all those who have spoken. I hope that the measures I have outlined in my response provide some confidence to those who live near the wreck, and to your Lordships, that the issue is taken with the utmost seriousness by the Government. The SS “Richard Montgomery” remains the most surveyed and the most monitored wreck in the country.
House adjourned at 8.23 pm.