Opponents of the Kudankulam Nuclear Power Plant, under construction in Tamil Nadu, are raising fresh questions about the plant’s safety because of Indian government documents that they say reveal a problem in the design of one of the two reactors.

The reactor’s design differs from the plan that Russia and India came up with when they agreed to build the reactor in 1988, according to the documents published by India’s Atomic Energy Regulatory Board.

The design of the reactor pressure vessel, which contains the reactor coolant and core, was not supposed to have welds in its core region, the bulletin said. The vessel has two welds there, it said.

People who live near the Kudankulam plant and the People’s Movement Against Nuclear Energy called this deviation a “serious breach of contract” that exposes the plant to high failure risk and a higher possibility of offsite radiological contamination.

“This is a breach of contract by the supplier in Russia. NPCIL (Nuclear Power Corporation of India) officers who knew [about] this breach are guilty of causing future financial loss by choosing lower quality equipment,” said Nityanand Jayaraman, environmental researcher and member of the Chennai Solidarity Group for Kudankulam Struggle.