I will address the depth of sampling first. The petitioner was concerned initially that samples had only been taken up to a depth of 5 cm. However, this was not correct. The committee heard that samples were taken and tested in 2009, 2013 and 2017. Some of the 2009 samples were taken up to a depth of 4.8m. The agencies involved in the testing have stated that they found no greater concentration of radioactivity at depth, and that led them to conclude that no further analysis of samples below the surface was necessary.

We were also informed that a key aspect of the testing process is a calculation of the dose that the dredging crew or the wider public could be exposed to from the material. However, during our investigations it emerged that a dose calculation had not been conducted on the 2009 samples. We requested that NRW ensure that this was addressed. This request was accepted and NRW informed us in late March that the dose calculation had been conducted retrospectively and had concluded that the material poses no radiological risk to human health or to the environment.

Nevertheless, the petitioners have continued to pose questions about the sufficiency of the testing. These include the number of samples taken at depth in 2009—which we understood to be five—and the fact that this exercise has not been repeated since.

The Petitions Committee considered that additional testing may provide further public reassurance. We wrote to NRW in January to recommend that they request the licence holder to arrange for further samples to be taken and analysed. They asked EDF to consider this on a voluntary basis, but this was rejected by EDF on the basis that the scientific evidence already demonstrated that the material is not radioactive. NRW also expressed the view that further testing was unnecessary and it was not something it could revisit through the licence or its conditions. Though we accept that the primary reasoning for additional testing was public reassurance rather than scientific necessity, the committee regrets that this recommendation was not taken forward. 

Moving on to the testing methodology itself, we considered a range of concerns about the testing carried out and, in particular, the range of radioactivity tested for. Full details are contained within our report and Members may be relieved to hear that I will not go too deep into the technical information during this contribution. The concerns amount to uncertainty over the limits of the gamma ray spectrometry techniques used, and the number of results that had previously been reported. Based on the previously published information, the petitioner had questioned whether all radionuclides had been tested for, or only those that had been reported as returning positive results. It has also been proposed—and confirmed by CEFAS—that the technique used could not directly identify alpha and beta forms of radiation.

However, the committee has received assurances from EDF, NRW and CEFAS that the testing and analysis has been carried out to the highest international standards, and that these are conservative in nature. We have also been told that the testing would have identified any gamma-emitting radionuclides present within the samples, and that the results were used to derive readings from other forms of radiation that are not directly identifiable using this technique.

A number of other concerns and questions have been raised and have received answers during our evidence gathering. These points are covered in our report and I am sure many will be covered during the rest of this debate.

In summary, our consideration of this petition has not resulted in a meeting of minds between those with concerns over this issue and the organisations and agencies involved. I think it would be fair to say that it was never likely to. Of course, we are reliant upon the scientific processes and the agencies that oversee them, as well as those who have responsibilities to protect our health and that of the environment.

I am sure that the level of concern and opposition demonstrated by the petition is a source of regret to those agencies. I hope that the evidence gathered by the Petitions Committee during our deliberations has helped to answer some of the questions that have been raised about this issue. We have made every effort to accurately report the evidence we received, and I also hope that people with an interest in this issue will read our report and perhaps find answers within it. All the evidence we heard is also published on the Assembly’s website for people to scrutinise.

Our understanding is that the dredging remains set to take place this summer, but that EDF are awaiting the conclusion of these processes at the Assembly. I feel it is right to acknowledge that. I will end my opening remarks there and I look forward to listening to Members' contributions this afternoon. Diolch yn fawr.