A private sector consortium will be told on Monday it has won the £7bn job of decommissioning Britain’s oldest nuclear power plants. The work is one of the largest and most sensitive public sector contracts to be awarded in the UK so far. Currently the sites are being run by Magnox, a company owned by Salt Lake City-based EnergySolutions. It is bidding for the new work in partnership with Bechtel. The only Magnox station still in use is in Wylfa in Anglesey, though this is due to stop producing electricity in the next two years.