Scientist calls for further testing on ‘nuclear mud’
ADECADES-OLD plutonium leak at a nuclear power station in itself justifies more sophisticated tests on mud dumped in the Severn Estuary off Cardiff, according to a physics professor at one of the world’s leading science universities.
Two years ago there were big protests when 120,000 tonnes of mud from Hinkley Point nuclear power station in Somerset were dredged across the Bristol Channel to a dumping ground near Cardiff Bay.
The Welsh Government refused to intervene, saying there was no truth in suggestions that the mud could be radioactive and harmful to human health.
The dumping was licensed by Natural Resources Wales (NRW). Now, as the French company EDF – currently building a new nuclear power station at the Somerset site – applies to dump up to a further 780,000 tonnes of mud from Hinkley Point off Cardiff, Professor Keith Barnham of Imperial College, London, has argued that NRW would be erring in its duty if it allowed that to happen without what he sees as appropriate testing going ahead.
In a submission to a public consultation on the plan, Prof Barnham states that data he has seen indicates that a 300 gram plutonium leak occurred in 1969 in liquid discharges from the then power station, known as Hinkley Point A.
He goes on to state there is also evidence for direct on-site plutonium contamination from cladding damage.
Asserting that the proposal to test by alpha spectroscopy for plutonium is better than the tests carried out before the 2018 dumping, which did not involve the alpha test at all, Prof Barnham says the samples taken need to be far more extensive than what has been proposed.
He states: “We conclude that if a plutonium signal is found, it is imperative that plutonium lung-burden tests of the type routine at Sellafield [nuclear power station in Cumbria] are made immediately on all the civil engineering workers at Hinkley Point C [as the power station under construction is known].”
John Wheadon, permitting services manager for NRW, said: “Our seas are home to valuable wildlife and habitats and are important to our well-being and economy.
“It’s our job to make sure activities do not harm these vital marine environments.
“Before the previous disposal activity in 2018, the sediment was tested and analysed thoroughly by independent radiological and public health experts, against internationally agreed guidelines, and the results showed the levels were within acceptable, safe limits for disposal at sea.
“We were satisfied that the disposal activity posed no risk to people or the environment.
“The Environment Agency regulates the Hinkley Point site, therefore we cannot comment on alleged historical incidents.”
Chris Fayers, head of environment at Hinkley Point C, said: “The second phase of dredging of mud from the seabed off the Hinkley Point C site is necessary ahead of drilling six vertical shafts for the cooling water system for the new nuclear power station.
“The mud is typical of sediment found anywhere in the Bristol Channel and no different to sediment already at the Cardiff Grounds site.
“Ahead of the second phase of dredging independent experts will carry out further analysis of the mud and sediment using techniques that are even more stringent than those used in 2017.
“During the first phase of dredging, Natural Resources Wales confirmed that independent analysis showed that the levels were so low as to be not classed as radioactive under UK law.
“It poses no threat to human health or the environment.
“No dredging will take place until Natural Resources Wales approve a monitoring and dredging plan. The next phase of dredging is not planned to take place until 2021.”