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AN EMBARRASSING rise in the cost of Sizewell B, Britain’s first pressurised-water
reactor, looks set to prolong the country’s latest nuclear power drama:
the Hinkley public inquiry. The hearing into the Central Electricity Generating
Board’s plan to build the country’s second PWR in Somerset, southwest England,
was scheduled to end on Wednesday. But on Monday the board revealed that
Sizewell B will cost 10 per cent more to build than anticipated, Hinkley
3 per cent more.

The inquiry is almost certain to be adjourned for three weeks to allow
participants to comment on the new information submitted at the eleventh
hour. The board blames a combination of factors for the price hike. The
cost of civil engineering, the nuclear steam supply system and the hardware
and software for the reactor controls and instrumentation have all increased,
justifying the board’s opponents who have long claimed the CEGB cannot get
its nuclear sums right.

Hinkley C, the scheme under consideration, is virtually a replica of
Sizewell B, the country’s first 1170-megawatt PWR, now under construction
on the east coast. The PWR is based on a design developed by the American
firm Westinghouse.

The CEGB is promoting PWR technology as the successor to 30 years of
reliance on home-grown gas-cooled reactors. The board wants the government
to approve a further two PWRs costing Pounds sterling 1500 million each.
Both power stations would be lookalikes of Sizewell B and Hinkley C.

Britain has blundered from one type of reactor to another, building
a succession of prototypes. This approach culminated in a disastrous sequence
of advanced gas-cooled reactors (AGRs). The board now wants to emulate its
Gallic counterpart, Electricite de France, by establishing a single design
and then building a rapid series of stations.

Ironically, Britain is about to embark on its PWR programme just as
France seems poised to halt its nuclear power plans. Britain is also adopting
a design that could look very dated within a few years. Westinghouse, the
company behind the CEGB’s design for a PWR, is collaborating with the Japanese
company Mitsubishi on an advanced PWR. At the same time, Westinghouse is
working on a smaller and safer PWR (Technology, 16 September 1989).

The CEGB had hoped that the hearing would be a formality. Eighteen months
ago the government approved the construction of Sizewell B, Britain’s first
PWR after an exhaustive public inquiry that looked in detail at the design
and safety characteristics of the PWR. Subsequently the Nuclear Installations
Inspectorate announced that it had no objections in principle to further
stations of the same design. So the board approached the inquiry into Hinkley
C expecting an easier ride.

Neither design nor safety were expected to be fundamental stumbling
blocks; nor was the cost of nuclear power seen as an issue. The board’s
case for building Hinkley C does not rest on economics. It relies on firmer
ground: government policy.

The government, worried about the threat to power supplies posed by
the coal-mining unions, is keen to ensure that the producers of electricity
do not rely on a single source of fuel. Around 80 per cent of electricity
in England and Wales now comes from coal-fired power stations.

The CEGB argued at the hearing which ended on Wednesday that Hinkley
C provides diversity of supply. Recent legislative moves have added momentum
to the policy.

Under the terms of the 1989 Electricity Act, which sets out how it will
privatise Britain’s electricity supply industry, the government is attempting
to quantify fuel diversity. The act stipulates that a specific proportion
of power generation must come from what are inelegantly termed non-fossil-fuel
sources. This is known as the non-fossil fuel obligation, or NFFO. In practice
the NFFO represents a mix of nuclear and renewable sources of energy. The
NFFO is expected to amount to around 20 per cent of the demand for electricity
by the year 2000.

Most of the board’s ageing Magnox nuclear power stations are scheduled
for closure by then. The CEGB estimates that by the turn of the century
there will be a shortfall of 3.2 gigawatts of generating capacity. The board
argues that it will need PWRs like Hinkley C to fill that gap and meet the
NFFO. Over the past week the board’s legal team has reminded Michael Barnes
QC, the inspector at the inquiry, of this aspect of its case. Lord Silsoe
QC, for the CEGB, has also reminded Barnes that the hearing’s remit does
not stretch to challenges to government energy policy.

Barnes has already begun to compile his report, which should be on the
desk of John Wakeham, the Secretary of State for Energy, within six months.
In the event, the proceedings, at the Somerset College of Agriculture, Cannington,
proved less of a fait accompli than the CEGB expected. The hearing coincided
with lengthy parliamentary wrangling over the proposals for privatisation
of the electricity industry. (The government published its bill on the privatisation
of the industry after the inquiry was under way.) The opponents to the board’s
plan exploited the resulting uncertainty.

Objectors complained that neither the government or the board had spelled
out the economic justification for fuel diversity. The Council for the Protection
of Rural England went further. It has persuaded the European Commission’s
Directorate of Competition to investigate key elements of the legislation
on privatisation, including the NFFO. Objectors believe that this may breach
the EEC’s rules on competition and state aid to industry. Critics of the
Electricity Act 1989 complain that the NFFO, coupled with the provision
of up to Pounds sterling 2500 million in state aid to meet nuclear costs,
represents featherbedding for nuclear power at a time when the government
is preaching the virtues of open competition.

Objectors at the inquiry scored a moral victory when they persuaded
the inspector to require the board to compare the economics of generation
from fossil fuel and nuclear power. After many years of extolling the economic
virtues of nuclear power the CEGB conceded that at the rates of return expected
by private investors (over 8 per cent) nuclear power stations are less economic
than coal-fired power stations.

If the legislation on privatisation cast a long shadow over the hearing,
so did the Chernobyl accident. Objectors to the CEGB’s proposal were dismissive
of the refusal of the Health and Safety Commission to quantify what constitutes
‘tolerable risk’ as far as nuclear power and the general public is concerned.

It did not help the commission’s stance that it excluded any quantification
of how the risk formula it adopted could assess the benefits of nuclear
power – nor that the National Radiological Protection Board disagreed with
the commission’s risk figure.

Both the CEGB and the NII rejected claims that they were complacent
over nuclear safety. James Reason, professor of psychology at the University
of Manchester, regaled the hearing with an incident at a Swedish nuclear
power station which demonstrated all the hallmarks of the Chernobyl incident.
It is widely recognised that the Swedes have the strongest safety culture
of any country operating nuclear reactors. Objectors raised other worries,
though not as persuasively as Reason.

French nuclear engineers, it appears, are investigating the performance
of control rods in their PWRs. Objectors argued that evidence from the accident
at Three Mile Island in the United States, where operator error led to a
partial meltdown of the reactor’s core, suggests that control rods could
melt if subjected to sudden temperature rises. The rods play a vital role
in shutting down the fission reaction in the event of an accident.

Just how seriously Barnes will treat some of this evidence remains to
be seen. He was impressed enough about the importance of Chernobyl to travel
to the Soviet Union to learn at first hand how the authorities coped with
the world’s worst nuclear power accident. No British public inquiry has
ever travelled so far to take evidence.

If, as seems likely, the board receives approval for Hinkley C it is
still not certain that the station will be built. Under privatisation the
CEGB will be split up: a new private company, called National Power, will
take on the responsibility for nuclear generation. Before it decides to
build Hinkley C it will have to ensure that it has contracts to sell the
power station’s electricity to the new privatised distribution companies.

This is proving easier said than done. The board has already cancelled
proposals for three large new coal-fired power stations because it cannot
agree terms with the distribution companies.

* * *

Leukaemia clutters the issue

THE CONTINUING debate over ‘leukaemia clusters’ in the vicinity of nuclear
installations was vented at some length during the hearing into the CEGB’s
plans to build a PWR at Hinkley Point. The debate was partly fuelled by
a report from the local health authority covering the site. This survey
suggested that there were more cases of childhood cancer than expected among
young adults of 15 to 24 years.

This report was published after the hearing began. But like every other
recent assessment of the phenomenom it failed to find a causal link between
radioactive discharges from nuclear installations and a higher incidence
of leukaemia.

The hearing heard that a number of uncertainties remain about some aspects
of the models used to predict the behaviour of radioactive material in the
environment and its transfer to human beings. The National Radiological
Protection Board is currently trying to answer some of these questions.

The CEGB made it clear that one explanation it favours centres on the
theory that childhood leukaemia represents a rare response to some unidentified
common infection or infections.

The argument runs like this. Epidemics are known to occur when outsiders
move into remote communities. They can be more susceptible. Nuclear plants
are generally sited in remote areas for safety reasons. The influx of construction
workers and then professional staff to run the nuclear plant could, according
to the theory, provide the trigger for the infective ‘epidemic’.

Leo Kinlen, from the cancer epidemiological unit at Edinburgh University,
is the researcher behind this theory. He has tested the hypothesis by looking
at leukaemia rates in remote populations where there have been large-scale
influxes of newcomers. Kinlen claims to have found such raised incidences
in a number of new towns established in hitherto rural areas. Other researchers
and epidemiologists, though, are very sceptical about this theory, pointing
out that the communities affected were not as isolated as Kinlen suggests.

* * *

Campaign for plutonium details

THE Campaign for Nuclear Disarmament has pressed the nuclear industry
and the government to release more details of the amount and fate of plutonium
produced in Britain’s civil reactors. CND has long claimed that in the past
plutonium has been illegally diverted from the civilian stockpile to military
use.

It now seems highly likely that before 1979 some plutonium from Britain’s
civilian Magnox reactors entered military use. This issue generated one
of the most electric sessions of the earlier Sizewell hearing and prompted
the inspector, Sir Frank Layfield, to recommend that the government should
publish full and accurate records of plutonium production from nuclear power
stations. The Department of Energy now publishes this material on an annual
basis.

CND returned to the fray at the Hinkley hearing to complain that the
information released is not as precise as it should be. The hearing learnt
that the CEGB submitted returns to the department rounded to the nearest
10 kilograms but the government publishes the data rounded to the nearest
50 kilograms. In the case of the board’s station at Wylfa, the largest single
producer of plutonium amongst the CEGB’s stock of Magnoxes, the rounding
is to the nearest 100 kilograms. It was clear from his questions that the
inspector did not regard this as a satisfactory state of affairs.

The inquiry also heard that there is an element of uncertainty about
the amount of plutonium locked in various waste streams at Sellafield where
spent fuel is reprocessed. Fred Passant, a key witness from the CEGB, told
the inquiry ‘it might be two tonnes; it might be three; it might be three-and-a-half’.
Information considered by the inquiry from British Nuclear Fuels suggested
that the amount of fissile material in waste contaminated with plutonium
is known more precisely than Passant suggested.

CND argued that if Passant’s comments were true ‘reprocessing should
clearly be brought to an immediate halt and the position rigorously investigated’.

The amount of plutonium in waste streams at Sellafield is not just an
accountancy headache. It also poses a problem for radioactive waste disposal.

At present Sellafield stores well over 60 000 cubic metres of plutonium-contaminated
waste. Known as PCM (plutonium-contaminated material), it is classified
as intermediate-level waste and is destined for disposal in a deep underground
repository. However, there is a question mark over whether this PCM is suitable
for disposal in this fashion. Much PCM is organic waste, discarded gloves
and so on. Organic material degrades over time. In a waste tip it breaks
down to form landfill gas, a process that could release highly radioactive
actinides.

Originally the nuclear industry hoped to recover more of the fissile
material in PCM. One promising technique involved a system which operated
on the principle of a washing machine, using caustic soda and a centrifuge
to wash out plutonium in the form of a powder. Scaled-up versions of this
system, says British Nuclear Fuels, which operates Sellafield, have not
proved technically suitable or as safe as needed for operators. BNF has
abandoned plans for a Pounds sterling 50 million plant which would have
recovered 2.3 tonnes of plutonium over the next 30 years. BNF is now experimenting
with a cement matrix to encapsulate the waste in a form suitable for burial.