19th October 2009
New reactor containment 'may not withstand high winds'
The US safety regulator has deemed that the containment structure of a reactor, possibly destined for Oldbury and other UK sites, 'may not withstand a tornado, earthquake or even high winds'. The Nuclear Regulatory Commission has directed the designers, Westinghouse, to strengthen the outer shell which protects the reactor's containment structure as it does not meet their requirements for safety.
E.ON, who are currently drilling ground at Oldbury in Gloucestershire to investigate its suitability for a new nuclear reactor, have said they would consider the Westinghouse AP1000 in question, alongside the French European Pressurised Reactor (EPR). The reactor designs are the only two being studied by the UK safety regulators the Nuclear Installations Inspectorate (NII). Two other designers dropped out of the assessment process.
The AP1000 was so called because of its novel 'Advanced Passive' systems which cut out about three-quarters of the valves, pipes and cables required by previously proven Westinghouse reactors such as Sizewell B. But these cost-saving measures, alongside a 50 percent reduction in concrete, have never been tested in a full-scale reactor.
The NII have already questioned the safety of the EPR's Control and Instrumentation system which governs all the key actions of the reactor and which may mean a delay in licensing while the complicated system is redesigned. The regulators were unhappy with a complex computerised system which could not be manually overridden. The NII have predicted their licensing process will be finished in June 2012 but have said the licence may allow 'exclusions' which would only be passed at a later date with complete information.
The EPR is also the subject of disputes between its French designers Areva and the Finnish builders who are jointly constructing the first of its kind in Olkiluoto , Finland . The project was due to be complete in 2009 but Areva now say it may not be complete till 2012. The Finnish regulators have also queried the control and instrumentation systems and raised questions over the wrong mix of concrete in the foundations and faulty welding of key components. Cost overruns have mounted to 3 billion euros.
Similar problems were exposed in the second EPR being built in Flamanville, Normandy .
Jim Duffy from Stop Hinkley said: "These findings are not just glitches. Westinghouse have made a virtue of their cost-cutting. To think they'd put forward designs that couldn't stand up to high winds makes you stand back and wonder about their integrity. The French reactor which EdF are pushing for Hinkley Point is having equally bad luck abroad. Getting their foundations wrong twice is very worrying. Time for a major rethink on the UK nuclear project."