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CONTENTS
Cancer in NW Wales
20 years on from the
Yorkshire TV programme "Windscale the Nuclear Laundry"
which revealed the existence of the notorious cluster of childhood
leukaemia at Seascale near Sellafield, a researcher from HTV has
done the same thing for the radioactively contaminated Menai Strait.
Like YTV, HTV has identified the children involved and has interviewed
them and their parents in a documentary broadcast on 10th February.
These are real children, so it will be hard for the authorities
to deny the data. The cluster is more severe than Seascale and its
statistical strength is greater.
In the seaside town of Caernarfon leukaemia in the 0 - 14 year old
age group is 28 times the UK national average (compared with Seascale's
12-fold excess). The excess risk is not confined to the town of
Caernarfon. In the 34 wards surrounding the Menai Strait there were
6 cases of leukaemia 0-4 from 2000-2003, a Relative Risk (RR) of
7.8; between 1996 and 2003 there were 9 cases of brain and spinal
cancer; RR = 5.4.
The cancers include 3 cases of the rare eye cancer retinoblastoma
on Anglesey. All are teenagers. In Conwy there are two further cases,
both under ten years old. Caernarfon has a further case, a child
born in 1999 and diagnosed at age 3. Retinoblastoma has been associated
with radioactivity since the Seascale cluster of leukaemia is accompanied
by a 20-fold excess of retinoblastoma in children of Sellafield
workers.
The relative risks for retinoblastoma in the HTV research are uncertain
because so far we only have one of the diagnosis dates, but a conservative
calculation shows that excess risks for the area, compared with
average rates, are between 5 and 15-times. The statistical significance
of all the results is high, so this is not a chance occurrence.
see
the detailed report on http://www.llrc.org.
WYLFA - YOUR TIME
IS UP
Britain's first generation of nuclear reactors, designed with a
20 year life have had their lives gradually extended. A secret CEGB
document from 1979 revealed that all Magnox plant could have a 25-year
life except for Wylfa "where a 20-year life should be assumed
because of higher gas coolant pressure causing increased steel and
graphite damage." By 1992 Nuclear Electric under economic pressure
announced that they wanted to keep them going for 30 years.
Wylfa which started in 1971 would thus have closed in 2001. A few
years later the Long Term Safety Review for Wylfa tried to make
the case for 35 years of operation, until 2006. The Nuclear Installations
Inspectorate (NII) accepted that Wylfa was safe to continue operating
only until 2004.
BNFL currently hopes that Wylfa despite all its problems can continue
to generate income, to offset massive liabilities at the other magnox
stations as they close, until 2010. To try to justify operating
Wylfa beyond 2004 BNFL have submitted a 'Periodic Safety Review'
to the regulator. The NII have until September to accept or reject
this case.
The ageing process The
'safety assessment principles' that guide the regulation of nuclear
reactors state that 'There should be an adequate margin between
the intended operational life and the predicted safe working life
of such components, structures and systems'. (P103)
At Wylfa three forms of deterioration in the reactor cores are a
particular cause of concern:
* Cracks have been found in welds where superheated steam tailpipes
from each boiler penetrate the steel liner of the reinforced
concrete reactor pressure vessel.
* Corrosion of the internal steelwork of the reactors, particularly
the core restraint
garter.
* Radiolytic oxidation (corrosion) or loss of volume of the graphite
core.
Wylfa's Reactor Pressure
Vessels contain not only the reactor core but the steam generators
(boilers). The cracks, found in 2000, are still there.
Instead of redoing the welds the superheater pipes have been 'braced'
outside the reactor pressure vessels to prevent the pipes 'popping
out' in the event of a weld burst. This bracing does not prevent
the vibration that might propagate faulty welds. In July 2003 further
defects were found in brackets which secure pipes to the pressure
vessel inside the reactor.
The consequences of steam being injected into the reactor core at
four times the pressure of the carbon dioxide coolant go way beyond
popping pipes out of the reactor. A pressure shock would be created
within the reactor by the differential between the steam pressure
at the top and the coolant pressure at the base of the reactor.
This would put great stress on the graphite blocks of the core,
and their steel support structure.
Because of their higher operating pressures Wylfa and Oldbury have
both suffered a greater loss of graphite volume (from radiolytic
corrosion) than that at any other Magnox stations. The volume of
the graphite has been reduced by up to 45% in the worst affected
areas, and failures are predicted. Graphite blocks that form the
reactor core are held together by vertical prisms of graphite known
as 'keys'. A 1991 Nuclear Electric core-integrity analysis* predicted
keyway failures at Wylfa before 35 operating years (2006) both in
peripheral positions at the base of the core and in interstitial-channel
bricks.
According to independent nuclear engineer John Large "There
is now considerable doubt that the graphite core could survive both
rapid reactor depressurisation and steam intrusion..."
The ageing process within
Wylfa's reactors has continued unabated since the Long Term Safety
Review in 1994. Measures such as the introduction of methane into
the coolant gas to try to slow down corrosion of the graphite will
have increased corrosion of the steel components supporting the
reactor cores.
Graphite is already cracking and corrosion has reduced its volume
and strength in critical areas. Reactors, designed to withstand
movement due to expansion and contraction during heating up and
cooling down have suffered non-uniform loss of graphite that threatens
their structural stability.
Latent failures in the
graphite will only become manifest if the core is subjected to a
physical shock such as a superheater weld bursting.
Displacement of graphite by more than two inches in any such failure
would prevent control rods being inserted to shut the reactor down.
At the same time it would restrict the flow of coolant gas to the
affected area and lead to a build-up of heat.
Wylfa's reactors, designed for 20 years, have now been operating
for 33 years. Failure of some components that lock the graphite
blocks together is predicted before 35 years Shut Wylfa NOW, before
it is too late.
Write to your MP and
your AM.
Ask what measures are being put in place to protect you and your
family from a 'beyond the design basis' accident at the ageing Wylfa
reactors. Ask for the publication of the documentation upon which
our safety depends.
* Metcalfe M.P. "Assessment of Graphite Brick Integrity in
the Wylfa Core"
Nuclear Electric Report TD/FCB/REP/0081 1991
NIREX Row
A plan to make the nuclear waste body, Nirex, independent of the
nuclear industry, announced last July by the Secretary of State
for the Environment, Margaret Beckett, has failed to appear. Nirex,
which has been lobbying to end its link with the nuclear industry,
blames BNFL, the government supported British Energy and the DTI
for the delay.
Defra claimed the problem was partly caused by a £500m loan
Nirex was said to owe the nuclear industry, along with £300m
of unpaid interest. But as both sums have already been written off
sabotage is suspected. Chris Murray, the chief executive of Nirex,
said "Certain individuals in the industry and DTI have been
fighting a rearguard action against Margaret Beckett's stated policy."
Nuclear power 'the
only realistic way forward
to satisfy Europe's energy needs'
On Feb 26th the European Economic and Social Committee adopted a
pro-nuclear Opinion entitled "nuclear power and electricity
generation. The result of the vote was 68 in favour, 33 against
and 11 abstentions. Subsequently, an amended text agreed on the
need for greater security measures for nuclear installations to
tackle the growing threat of terrorism.
Apart from exacerbating the problems associated with climate change
the committee opined that abandoning nuclear power would be prohibitively
expensive for EU consumers given the current lack of suitable and
viable alternatives such as renewable energy. Renewable energy sources
was not yet in a position to satisfy Europe's energy requirements,
even taking into account the increasing public incentives. Nuclear
power must be one of the elements of a diversified, balanced, economic
and sustainable energy policy within the EU.
Respecting the stabilisation commitments on CO2 emissions at the
present time would not be possible without further advances in technological
development and consumer behaviour. Nuclear power was also essential
if the EU is to successfully apply the concept of sustainable development
to policy making.
Angela Pfister (Austria) who emphasised the need for "a balanced
attitude towards this subject" felt that the text presented
left out important details on the security and risk elements associated
with nuclear power.
Far more detail was needed in the text on safeguards for nuclear
facilities against the threat of terrorism and as for the economic
arguments about the profitability of nuclear power. "If nuclear
power was such good business then why had it failed in the UK?".
The Rapporteur argued that nuclear power represented the only realistic
way forward to satisfy Europe's energy needs, a stance echoed by
Commissioner Loyola de Palacio. "I'm firmly in favour of renewable
energy but at present it cannot replace the percentage of Europe's
energy needs currently satisfied by nuclear power".
"If we were to unplug our nuclear power stations tomorrow we
would have to accept a radical change in our way of life" she
added. Concerning terrorism, this is a general problem and concerns
all economic activities. Acceptance of nuclear power today did not
however mean that the development of alternative sources of energy
for tomorrow should not be encouraged.
"Nuclear power was not a panacea" she stressed also indicating
that more transparency within the sector was need to bolster public
confidence in nuclear power.
CoRWM get to work
CoRWM has established a working group to determine the inventory
of radioactive wastes, including "some radioactive materials
requiring to be dealt with as if they are waste, that will need
to be managed in the longterm".
The Committee's 'priority task' is to recommend what should be done
with the wastes for which no long-term management strategy currently
exists - that is, high (HLW) and intermediate (ILW) level wastes
now in storage or likely to arise in the next century or two, and
some low level wastes (LLW) unsuitable for disposal at Drigg. CoRWM
now has a website: http://www.corwm.org.uk
WANA Comment
Long term deferral of reactor decommissioning does not represent
an acceptable long-term management strategy for this waste.
The Radioactive Substances Act 1993 definition of radioactive waste
is stringent and includes any 'substance or article which has been
contaminated in the course of production, keeping or use of radioactive
material'.
According to DEFRA: Government is beginning to give consideration
to this issue jointly with the Nuclear Decommissioning Authority,
to try to scope the magnitude of the problem.
Meanwhile DTI are busy setting up the NDA, and consulting on policy,
in the hope that CoRWM is going to come up with a 'national repository'
to take all the decommissioning wastes that arise from dismantling
reactors.
Our advice to the NDA is simple: you are going to have to sort out
long-term radioactive waste management yourself.
WANA's full response to the DTI decommissioning policy consultation
is available by email: hughrichards@gn.apc.org
The main points are set
out below:
* Decommissioning policy is to be driven by the need for safety,
and the progressive reduction of hazards.
* It is to be consistent with the principles of intergenerational
equity and sustainable development.
* The application of decommissioning policy on the site of each
nuclear plant is not affected by the presence or absence of facilities
off-site for the long term disposition of radioactive waste.
* After plant shut down all radioactive waste on the site is to
be retrieved, conditioned and placed in a passively safe state in
purpose built stores on each site.
* Nuclear reactor blocks contain intermediate level radioactive
waste in a configuration that was not designed for its long term
storage, cannot meet the criteria of passive safety that are regarded
as essential, and will increase the hazards over time. Regulatory
guidance, based on the sound management of scientific uncertainties,
states that after some decades, a time is reached when any further
reduction in the radiological hazard is insignificant due to the
presence of the much longer lived radionuclides.
* Nuclear facilities are to be decommissioned as soon as it is reasonably
practicable, defined as without delay other than that necessary
to plan for the work to be done safely.
* As there are no substantial safety benefits in deferring reactor
dismantlement beyond 30 years, it is the explicit policy of this
Government that reactor dismantling to facilitate passive safe storage
of all radioactive waste is to be achieved within this period after
shut-down.
Nuclear Renaissance
in the UK?
Current energy strategy is to be reviewed in 2005/6. According to
POST (Parliamentary Office of Science and Technology) new nuclear
build via a White Paper would need to address market acceptability,
adequacy of the skills to build and regulate new plant, and public
acceptability of long term management strategy for radioactive waste.
No mention of making new nuclear reactors terrorist proof.
Full report on http://www.parliament.uk/post
EVENTS
April 9th- 12th March from London to Aldermaston Contact CND Cymru:
01550 750260 April 24th 11am WANA Meeting - Cardiff County Hall
Atlantic Wharf, Cardiff July 3rd, 4th Low Level Radiation and Health
Conference email: jillandmark@lineone.net
Published by WANA PO
Box 1 Llandrindod Wells LD1 5AA Tel: 01982 570362 Email:
hughrichards@gn.apc.org
web URL http://www.kare-uk.org/wana-index.htm
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