The Atomic Energy Regulatory Board on Friday gave its nod for the loading of fuel in the first unit of the Kudankulam nuclear power plant in Tamil Nadu, marking a significant movement forward towards the commissioning of the plant.

The regulatory body also gave its approval for the “first approach to criticality’’ of the unit. In other words, it has also given the green signal for commencement of the controlled nuclear fission process in the unit.

Announcing the decision, an AERB press release noted that the clearance issued for fuel loading and first approach to criticality was the culmination of detailed review of the safety analysis reports along with the various documents submitted by the Nuclear Power Corporation [NPCIL] regarding fulfilment of the different pre-requisites.

The release also noted that the fuel loading and commencement of controlled nuclear process would be carried out under the supervision of AERB officials, who will ensure that all safety measures were in place and verify compliance to AERB approved procedures.

This initial fuel loading is a full core loading of the reactor and the quantity of fuel in the core is about 79-80 tonne of low enriched uranium fuel (LEU) bundles contained in 163 fuel assemblies.

Speaking to The Hindu, AERB Chairman, S.S.Bajaj, said fuel loading was likely to begin in about a week after NPCIL met certain pre-requisites and it would be completed in a few days.

The unit, he said, could go into operation by the middle of October, after several rounds of tests. “The NPCIL would again come to AERB to get clearance for going critical once the loading process is over’’, he said.

The nuclear plant, with two units of 1,000 MW capacity each, has been built with Russian collaboration. It will use light water as both coolant and moderator. Russia has provided all equipments including the reactor pressure vessel, steam generators, and turbines and will supply the fuel for the life time of the reactors.

The AERB press release observed that the design of the plant had several advanced safety features and that after the nuclear accident at Fukushima in Japan last year the Board had carried out a safety reassessment of its capacity to withstand extreme external events and non-availability of power supply for an extended period.

The first unit was earlier scheduled to go on stream about a year ago itself But, the work was suspended after the Tamil Nadu Government asked the Centre to halt all operations till the villagers in the neighbourhood of the plant, who had launched a protest on the safety aspects, were reassured that there would be no danger to them. Following a series of meetings and reports by experts committees, the State Government gave its nod for resumption of work in March this year.