Half-a-century after launching the nuclear programme, India has finally begun working on a “deep geological repository” to permanently store its nuclear waste.
Over the next five years, scientists are going to study a set of physical and geological parameters required for setting up the nuclear waste storage facility before zeroing in on its location.
The options vary from underground storage in rocky central India to plains where the storage may be housed inside layers of clay.
“We will use an existing underground mine to study conductivity, heat management and percolation and rock stability. The site has to be totally impervious, geologically stable and without any fissure,” Department of Atomic Energy Secretary Srikumar Banerjee said here.
Nuclear waste generated in India so far is too small to deserve a separate repository. But as the country plans an ambitious growth in nuclear power – 63000 MW by 2032 – a waste disposal site would eventually be required.
Absence of a publicly known plan to deal with nuclear waste was always cited as one of the crucial arguments by the anti-nuclear lobby to oppose the nuclear power.
“Globally there is no deep geological repository for nuclear waste. Work on the proposed site at Yucca Mountain is also delayed. The DAE decision to work on a DGR in India will help boost people's confidence in nuclear energy,” said C Ganguly, former head of Nuclear Fuel Cycle and Materials section at the International Atomic Energy Agency in Vienna.
India's existing nuclear waste site is located at Tarapur where high-level radioactive waste is first converted into inert and stable materials which are kept inside stainless steel canisters sealed with lead covers. Almost 75 per cent of this solid storage surveillance facility is still vacant.
Only one-sixth of the space has been occupied so far as each 540 MW nuclear plant generated 5 tonnes of wastes every year and 220 MW plants produce about 2.5 tonnes of waste annually, explained R K Sinha, director of Bhabha Atomic Research Centre, Mumbai.
A second waste disposal unit will come up in Kalpakkam during the 13th plan period.
The two sites could take care of the nuclear waste in the next two decades as India's nuclear generation is rather small, said Banerjee on the sidelines of a conference at Indian National Science Academy on Tuesday.
The proposed DGR will have large chambers with adequate shielding where nuclear waste from all over the country will be transported periodically. There would be also automatic heat management and radioactivity monitoring.
The Tarapur facility consists of an underground hydraulic vault, which in turn houses two more vaults, which can store about 1700 casks for 20-30 years before they are transported to the deep geological repository.