Days before the Nuclear Power Corporation of India Limited (NPCIL) is set to insert fuel rods into the Reactor Pressure Vessel (RPV) of the first two units of the Kudankulam Nuclear Power Project (KKNPP), the Peoples' Movement Against Nuclear Energy (PMANE) has expressed doubt that the reactor vessels could be of low quality.
Addressing a press conference here on Saturday, PMANE representatives, including V.T. Padmanabhan, R. Ramesh and Nityanand Jayaraman, claimed that the NPCIL and the Atomic Energy Regulatory Board (AERB) had accepted a lower-quality RPV, which had two welds in the core area, against the contracted design without welds. This could be a breach of the Indo-Russian agreement on the Kudankulam plant.
The RPV, a 19 metre high, 4.5 metre wide cylindrical structure made of 200 mm steel, is critical to radiation safety as it houses the reactor core (fuel assembly) and the coolant system, the activists claimed.
They said that a document authored by NPCIL scientists, led by the late S.K. Agarwal in September 2005, stated that as per the original contract, the RPV would be constructed without welds in the area surrounding the reactor core. Another AERB document, released in 2008, said that the vessel used had two welds in the core region.
“Tremendous care must be taken to ensure that the steel casing used for RPV does not become brittle with time after it is bombarded by neutrons,” said Mr Padmanabhan, PMANE's expert committee member. The activists said the locals and Parliament should know from the AERB what tests were conducted and the results.
The International Atomic Energy Agency (IAEA) and the European Union (EU) insisted that welds in the core area, if any, should be subjected to tests that assess their strength under rapid temperature fluctuations. “Such tests can't be conducted after the insertion of fuel rods,” said Mr. Ramesh.
As RPV housed all radiological components, its integrity over the lifetime of the reactor was of paramount importance. This assumed significance in the light of the NPCIL's denial to publish the safety analysis report, despite an order by the Central Information Commission to reveal its contents, said Mr. Jayaraman of the Chennai Solidarity Group for Koodankulam Struggle.