EDF, the French state-backed utility, said it was seeking to hold an extraordinary board meeting of its joint venture nuclear power plant in southern China after a report of a possible radiation leak.
EDF said on Monday that it had been “informed of the increase in the concentration of certain noble gases” in the first reactor at Taishan Nuclear Power Plant, which is majority held by China General Nuclear Power Corp. Noble gases are inert gases, such as helium, xenon and radon.
It added that such increases were “a known phenomenon, studied and provided for in reactor operating procedures” but said it was calling for the extraordinary board meeting to review all available data.
EDF said later on Monday that the build-up of inert gases in Taishan seemed to be because of issues with the casing around some fuel rods, which represented the first of three containment barriers at the reactor.
The first indication of a potential problem dated to October 2020, EDF said, adding that the measurements of the inert gases were, based on data at its disposal, below the maximum levels authorised in China. It said that it was too early to judge if the reactor would need to be halted to fix the problem.
In a statement posted on its website on Sunday night, the Taishan Nuclear Power Plant said its two reactors were operating normally. “The [plant’s] environmental indicators and its surroundings are normal,” the plant said.
It added that the plant’s second reactor had recently completed a scheduled overhaul and had been reconnected to the electricity grid on June 10.
Taishan is 70 per cent owned by CGN, with the remainder held by EDF. It is the first nuclear plant in the world to operate a European Pressurised Reactor, a Franco-German technology that had been haunted by delays and cost overruns for two decades.
The Taishan plant’s first reactor began commercial operations in December 2018, with its second reactor coming on stream in September 2019.
Taishan, population 1m, is about 75km west of the Pearl River Delta, the most densely populated part of southern Guangdong province. Hong Kong is about 140km from the power plant.
CGN and EDF are also collaborating on an EPR nuclear plant in the UK, which is under construction at Hinkley Point in Somerset.
Citing unidentified sources and documents, CNN reported on Monday that EDF unit Framatome had recently informed the US government of a potential “imminent radiological threat to the site and to the public”.
“Framatome is supporting resolution of a performance issue with the Taishan Nuclear Power Plant,” Framatome said in a statement on Monday, adding that “according to the data available, the plant is operating within the safety parameters”.
The French government was following the situation, according to officials.
CNN said that President Joe Biden’s National Security Council was monitoring the situation but did not yet think that a “crisis level” had been reached.
CGN declined to comment. The Taishan municipal government and China’s National Nuclear Safety Administration were not immediately available for comment on Monday, a Chinese public holiday.
Nuclear power is central to President Xi Jinping’s ambitious environmental goals, which include achieving net zero carbon dioxide emissions by 2060.
There are about 50 nuclear reactors operating in China, accounting for about 5 per cent of total power generation.
Additional reporting by Qianer Liu in Shenzhen