At a board meeting of TNPJVC on 22 July, EDF explained its position on the events at unit 1 of China’s Taishan NPP which had earlier experienced fuel rod leakage. TNPJVC is a joint venture owned by China General Nuclear (70%) and EDF (30%), which is responsible for the operation of the Taishan NPP.
Following the detection of unsealed assembly rods at Taishan 1, EDF teams, who contribute their expertise and skills, analysed the data provided by the operator, particularly the data relating to the chemical composition of the primary circuit water, and assessed its consequences particularly in relation to the evolving nature of the situation.
EDF confirmed that, according to the data available, the radiochemical parameters of the primary circuit water remained below the regulatory thresholds in force at the Taishan plant, thresholds which are consistent with international practices. The situation is evolving and is being continuously monitored by the operator.
However, on the basis of the analyses, EDF said its operating procedures for the French nuclear fleet would have led EDF, in France, to shut down the reactor in order to accurately assess the situation in progress and stop its development. In Taishan, the corresponding decisions are the responsibility of TNPJVC.
An increase in radiation levels had been detected in the primary circuit at unit 1 of the Taishan plant on 14 June, but was within the parameters for safe operations. The increase was caused by damage to the cladding in a small number of fuel rods, which is normal during the production, transportation and loading of fuel, China's Ministry of Ecology & Environment (MEE) noted. It estimated that around five of more than 60,000 fuel rods in the Taishan 1 reactor core had been damaged, amounting to less than 0.01% of the total, far below the maximum design level of 0.25%.