Nuclear safety issues are the focus of a public inquiry to determine whether a British utility will be allowed to construct an American-designed pressurized water reactor here.
There has already been a year's debate on the economics of the controversial project.
The proposed station, called Sizewell B, would be the first of its kind in Britain. It would be built next to an existing gas-cooled nuclear station called Sizewell A on the Suffolk coast north of Ipswich.
The Central Electricity Generating Board, the utility providing power to England and Wales, has nine nuclear power stations in operation. They supply 11 percent of its electricity and use British-developed gas-cooled technology.
To decrease reliance on coal, the utility plans to build more nuclear plants and has abandoned the gas-cooled reactor in favor of a pressurized water reactor designed by Westinghouse Corporation.
Objectors at the inquiry, including the Greater London Council and other local authorities as well as planning, environmental, trade union, and consumer groups, question the need to build any new power plant with a $1.8 billion price tag in view of Britain's current surplus of electrical generating capacity.
And they claim the pressurized water reactor, the type of reactor involved in the 1979 Three Mile Island incident, has disturbing safety problems.
Public attention has recently been focused on nuclear safety matters by the discovery of plutonium contamination near Britain's fuel reprocessing plant in Cumberland, forcing the closure of 25 miles of beach to the public, and the announcement of two sites for permanent nuclear waste disposal.
''It's quite clear that if the inspector says go ahead and build Sizewell, it will be the first of a program of new reactors,'' said Jennifer Armstrong of the Town and Country Planning Association.
Tim Beaumont, chief press officer of the generating board, agreed that more pressurized water reactors are likely to follow if Sizewell B is approved.
''Assuming we get permission to build Sizewell, we'll immediately apply for a second pressurized water reactor at Hinkley,'' he said, adding that four possible sites have been announced as candidates for a third pressurized water reactor.
Objectors view the Sizewell case as an opportunity to make major shifts in Britain's energy policy. ''If we stop Sizewell B, that's it for nuclear power in Britain,'' asserted John Valentine of the Stop Sizewell B Association.
The outcome of the inquiry may affect the sale of Westinghouse reactors to other countries. ''Clearly it has to be a very valuable shop window for them (Westinghouse),'' Mr. Beaumont said. ''The accolade of a British safety license must be very desirable.''
The British choice of a Westinghouse reactor, in view of their long experience with nuclear matters, ''is quite an endorsement of the reactor and the design, and it does help in that regard,'' said James Moore, head of Westinghouse's reactor division.
But Mr. Moore denied allegations by objectors that Westinghouse hopes to use the inquiry to boost its reactor export industry and compensate for a stagnant domestic market in the United States. (No new reactor orders in the US have been placed since 1979.)
''There have been some things bandied about to the effect that Westinghouse is on the ropes and if we don't get this, we'll go out of business. That's not the case at all,'' he said.
According to Ms. Armstrong, although approval for Sizewell B ''could mark a new upsurge of nuclear projects here and abroad,'' a deferment or rejection of the Sizewell proposal ''would be a very bitter blow to the American and British nuclear industries and a very big boost for those pushing for renewable sources of energy, conservation, and efficiency improvements.''
Mr. Moore called such assessments ''very speculative. It would depend on why it was turned down. If it's specifically because of British economics, well then that will be recognized, and it would have very little effect outside Britain.''
The generating board is spending between $15 million and $25 million to present its case. Objectors were denied their request for public funding.
The East Anglian Alliance Against Nuclear Power, a coalition of 60 groups, boycotted the inquiry. ''The decision to not fund objectors, while the generating board has full access to public funds, makes it hopelessly uneven from the start,'' spokesman Roy Thompson said.
Although Sizewell B is ''not needed purely on capacity grounds,'' Beaumont said, ''the power from this station will be so cheap it will pay for itself over the long term'' by replacing aging coal-fired plants and ''adding to Britain's fuel diversity.''
But according to Valentine, the favorable ''net effective cost'' calculated by the generating board is based on questionable assumptions about future electricity demand, construction time, and the price of coal. Although the utility estimates a 7 1/2-year construction period, similar four-loop Westinghouse reactors built in the United States have averaged 8 1/2-year construction periods. One is expected to take 12 1/2 years to complete.
''What makes them think we can do it so quickly the first time?'' Valentine asked, noting that a recent, gas-cooled nuclear station at Dungeness took 17 years to build.
The generating board says it believes new technologies that are dependent on energy will offset energy conservation and efficiency programs.
''Like everyone else, we've been wrong in the past with our projections, but we believe the construction of the (pressurized water reactor) is necessary if we're to contain the rise in the unit cost of electricity,'' Beaumont said.
But objectors believe Sizewell's cost is more likely to contribute to a rise in energy prices. They argue that the almost $2 billion of capital could be better spent resuscitating the British economy or researching alternative energy sources.
The generating board also considers the investment in Sizewell essential to prevent Britain's nuclear industry from collapsing.
''Even if the economics were marginal, we would go ahead and build it, for the benefit of keeping future options open,'' Beaumont said. ''If we waited until Sizewell was needed on capacity grounds, the British nuclear industry would disperse. It's important to keep our capability to build nuclear plants together as an industrial resource.''