Unions representing 12,000 nuclear workers are to reject a pay offer, raising the prospect of industrial action just as the Government privatises the running of Britain’s fuel reprocessing centre.

The Times has learnt that three unions will throw out a 2 per cent pay offer and begin to ask members about support for a strike next week in a dispute that centres on Sellafield, the reprocessing site in Cumbria; Sellafield’s technical facility at Risley, near Warrington; and Capenhurst, the former uranium enrichment plant in Cheshire that is being decommissioned.

Final bids for the contract to run Sellafield are due to go to the Nuclear Decommissioning Authority (NDA), the body charged with selling the last of the state-owned nuclear assets, on Monday. The preferred bidder, which could want to receive about £20 billion over a 20-year period, will be selected in the summer and will begin to run the site in the autumn.

Any industrial action would compound the problems at Sellafield, which has suffered severe technical issues at Thorp, its newest reprocessing facility.

Nuclear workers previously have received relatively generous awards, but unions believe that the latest below-inflation offer is too little during a time in which the nuclear industry is undergoing considerable change.

Mike Graham, national officer for energy at Prospect, the engineering union, said: “We are absolutely disgusted with the pay offer and it could well lead to industrial action. This is the time of the biggest change for Sellafield and we are being offered a very low reward.”

Prospect’s opposition to the offer is backed by the GMB and Unite, the general unions.

A spokesman for Sellafield said: “Our offer is intended to help increase the efficiency of the business, which is a necessary step towards securing our long-term future. The offer is in line with the Government’s recently published public sector pay guidelines.”

Four groups are vying to run Sellafield and they are expected to want about £5 billion for the first five years, with an option to extend for a futher 15 years. They are a consortium involving Bechtel, the American engineer, and Serco, the British services group; Amec, of Britain, Washington Group, of the United States, and Areva, of France; a team led by Fluor, another American business, and Toshiba, of Japan; and a group led by CH2M Hill, of the US.

The NDA has been testing the groups onsite. It has said that the process is on schedule. However, it has suffered the loss of several directors over the past few months and was involved in a controversy after it underestimated its own running costs.

Sellafield is expected to be at the heart of the next generation of British nuclear facilities. New reactors are certain to be built on existing nuclear sites and some prospective builders are thought to have inspected Sellafield’s potential already.

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