N-Base Briefing 325 - 11th May 2002
Pollution may be recent
The UK Atomic Energy Authority's assertion that the
radioactive particles which have been found on the foreshore at Dounreay,
on the nearby Sandside beach, and on the seabed were the result of unplanned
discharges in the 1960s was seriously undermined at this week's meeting
of the Dounreay Particles Advisory Group (DPAG). Instead expert independent
evidence now suggests the contamination was still being put into the environment
as late at 1996 - and may still be entering the environment from some as
yet unknown source. DPAG was set-up by the Scottish Environment Protection
Agency to try and understand the source and extend of the contamination.
This week's DPAG meeting in Thurso heard startling
new expert opinions which shatters the stand taken up until now by Dounreay's
operators. Some of the new conclusions come from new information provided
by UKAEA about past operations at the plant.
Instead of insisting that the particles must have originated
from operations in the 1960s, Dounreay has now agreed that crushing and
cropping of spent fuel for reprocessing produced the radioactive particles
until 1996. DPAG has "received clear evidence that significant quantities
of particles may have been discharged via the non-active drain system"
and this information may be vital in understanding how the contamination
has spread in the environment. Also the waste silo into which the particles
should have been dumped was not fitted with filters until 1984.
In addition DPAG has identified a route for particles
from the Dounreay Fast Reactor to enter the low active drains and now
believes that the use of high pressure hosing at the site in 1983 may
have resulted in the further discharges of particles into the environment.
One possible source of some of the contamination has
been the now disused discharge chamber on the seabed off Dounreay. This
has been disused since 1992 when a new pipeline was built, but Dounreay
has often said it believed particles trapped in the chamber may have been
escaping. It has now emerged that the old pipeline and chamber were in
fact flushed out by UKAEA every month from 1992 to 1997 when the chamber
was capped.
The DPAG experts add: "the possibility of a continuing
source of particles entering the environment requires further work".
Meanwhile Professor Keith Clayton, an expert commissioned
by the UKAEA, has said that there may be as few as 2000 particles on the
seabed off Dounreay, based on the results of the seabed survey by divers.
However, as the UKAEA admits there is evidence of possibly hundreds of
thousands of particles being discharged in the 1960s alone, Prof. Clayton's
opinion raises the question of what happened to the rest of the contamination.
UKAEA has asked him to try and answer this question for them.
Monitoring contract under fire
The decision by the UK Atomic Energy Authority to
award the contract for monitoring five beaches around Dounreay for contamination
- including Sandside beach - to the present contractor, RWE Nukem, has been
criticised by the chairman of the special Dounreay Particles Advisory Group
set up by the Scottish Environment Protection Agency. Mr Campbell Gemmell
said the members were unimpressed by the technical specifications for the
monitoring in the successful tender proposals which is due to start on 1st
July.
Present monitoring has been widely criticised, not
least by the Sandside beach landowner Mr Geoffrey Minter and his expert
advisers, and improvements in the equipment and techniques used were widely
anticipated - so criticism of the UKAEA's decision will be come as no
surprise. Indeed it was recognised in the UKAEA announcement.
This stated: "While the bids [for the contract]
contained improvements on the current technology, UKAEA is concerned that
none of the bids may fully meet stakeholder expectations of significant
improvement that some experts consider possible. The current contract
for beaches monitoring expires on 30 June 2002.
Following careful evaluation of each bid, UKAEA has
concluded that the tender submitted by RWE Nukem has the greatest potential
of being able to meet stakeholder expectations. UKAEA therefore has awarded
a contract for beaches monitoring from 1 July 2002 that is conditional
on the company being able to demonstrate that its system meets the specification
for monitoring laid down by the Scottish Environment Protection Agency.
UKAEA will monitor closely the performance of RWE Nukem and encourage
the company to develop its system further to meet the expectations of
stakeholders."
New discharges required for safety says UKAEA
Dounreay is asking regulators for permission for
new discharges of radioactive waste into the Pentland Firth following safety
concerns over a waste storage tank. Regulators have expressed concern about
the integrity of a so-called 'floc storage tank' - used to store intermediate-level
reprocessing wastes. To overcome the concerns UKAEA wants to transfer some
liquid waste from the tank causing concern to a new tank - but this is not
large enough to hold all the waste which needs moving and still have enough
space capacity in case of an emergency. UKAEA therefore wants to discharge
into the sea the balance of the waste in the suspect tank to reduce the
level to what is considered safe. UKAEA states that: "the phased discharge
of the liquid would represent no more than 6.6 per cent of the site's annual
limit for discharges into the sea." No further details have been released
either by UKAEA or the regulators so it is unclear at present whether the
annual limit referred to is the total for the site, or one of several limits
imposed on particular buildings or processes.
Sodium clean-up
A conference in Thurso this week organised by the
Organisation for Economic Co-operation and Development looked at Dounreay's
experience in dealing with decommissioning liquid metal coolants used in
fast reactors. Over 1,500 tonnes of radioactive liquid sodium is being treated
at Dounreay in the largest plant of its kind in the world.
THORP behind again
Already behind schedule, BNFL's Thermal Oxide Reprocessing
Plant (THORP) at Sellafield is set to fall even further behind as a result
of maintenance during 2002-03. Having reprocessed around 750 tonnes of oxide
fuel last year (2001/2), THORP has been shut down since mid-March for maintenance
and is expected to re-start later this month. Three further 'engineering
outages' for THORP during the year are highlighted in the Nuclear Installations
Inspectorate's (NII) latest Sellafield Quarterly Report. Customers' Baseload
contracts amounting to 7000 tonnes were to have been completed in the first
10 years of THORP's operation - by March 2004. Now in its 9th year of operation,
THORP has reprocessed a total of around 3900 tonnes - just 55 per cent of
the Baseload. Problems in the plant and within downstream facilities since
its start-up in March 1994 have already forced BNFL to extend the completion
date of the Baseload contracts by one year to March 2005, to the annoyance
of the company's overseas customers. To meet this revised date, THORP was
required to reprocess an average of 955 tonnes every year.
Opposing plans
Nuclear generator British Energy and the nuclear
waste agency, Nirex, are reported to be submitting objections to the proposed
changes in the UK's planning laws. The government is proposing to make it
easier in England and Wales for major national projects, such as nuclear
reactors and new roads, to get planning permission. Parliament will decide
'in principle' on a project and any public objections will only be allowed
on local issues, such as access.
Yucca too small
US energy secretary Spencer Abraham has admitted
that the proposed nuclear waste dump at the Yucca mountain site in Nevada
will be too small to take the country's stock of spent fuel and other wastes.
The site is planned to take at least 3,000 tons a year for 23 years. However
the US's stock of radioactive waste is expected to be 65,000 tons before
the dump is ready and nuclear reactors will be producing a further 2,000
tons annually.
Irish monitoring results
The Radiological Protection Institute in Ireland
has published its monitoring results for radioactivity in the environment
in 1999 and 2000. Radiation from Chernobyl and weapons testing were still
present and krypton-85, a radionuclide released during reprocessing at Sellafield
and La Hague in France, is also detectable in the air. The institute said
results were broadly similar to earlier years - except for krypton-85. This
had shown a small increase, following a consistent trend since monitoring
started in 1993. Full details are available at www.rpii.ie
Dock abandoned
The Ministry of Defence has abandoned building a
new jetty on the River Tamar originally intended to be used for re-arming
nuclear submarines. The work is presently carried out at the Devonport dockyard
in Plymouth and with the abandoning of the new jetty the work will continue
at Devonport. The new jetty was opposed by environmental interests and about
GBP20 million has been spent on the project. The ministry said work was
started because of concerns over safety for people living near Devonport,
but a new study had shown the risks were less than originally thought.
Energy consultation
Following the publication earlier this year of its
Energy Review, the UK Government has announced a public consultation on
energy policy in advance of a White Paper expected at the end of the year.
Details can be found on the following web sites www.dti.gov.uk/industries_energy.html
www.dti.gov.uk and www.defra.gov.uk Friends of the Earth said the consultation
document moved away from the statements on renewable energy in the Energy
Review and re-opened the possibility of a public subsidy for nuclear power.
Emergency exercise
One of the UK's largest civil emergency exercises
was carried out last week at the Bradwell nuclear reactor in Essex. Its
two reactors were closed earlier this year. The exercise involved the crashing
of a fully-loaded medium-sized aircraft into the nuclear power station.
Through canal
The two British Nuclear Fuel armed vessels passed
have passed through the Panama Canal en route for Japan to return to the
UK the plutonium Mox fuel whose safety data had been falsified. The Pacific
Pintail navigated the canal last weekend and the Pacific Teal on Wednesday.
Arrival in Japan is expected to be in early June - during the football World
Cup. The Caribbean foreign ministers meeting in the Council for Foreign
and Community Relations (COFCOR) issued their strongest condemnation yet
of the shipment of hazardous nuclear material through their waters. The
ministers stressed their "implacable and steadfast opposition to the
continued use of the Caribbean Sea for the trans-shipment of nuclear waste".
BE losses
Nuclear generator British Energy lost GBP493 million
last year according to its figures published this week. The company said
this was mainly due to exceptional one-off charges. UK losses rose to GBP41
million.
Safety award
Sellafield is one of the safest sites for industrial
accidents in the country according to the latest awards from the Royal Society
for the Prevention of Accidents. Sellafield collected 24 awards.
Reactor restart
The Tennessee Valley Authority has voted to re-open
the Browns Ferry nuclear plant which was shutdown in 1985 due to safety
concerns. Improvement work is scheduled to start next year and be completed
in 2007. The three board members argued that the reactor was needed to cope
with power demands.
Dump opposed
The South Australian state government has re-affirmed
its opposition to plans to build a low-level nuclear waste dump near Woomera.
"This is just another step by the commonwealth government towards making
south Australia the nation's radioactive waste dumping ground", the
state environment minister, Mr John Hill, said this week.
July threats
American intelligence officials are privately warning
that threats have been make by terrorists for an attack on a nuclear plant
on 4th July this year.
Nuclear needed
The British Nuclear Industry Forum has published
a study it commissioned which shows nuclear energy is needed if the UK government
is to meet its carbon emissions targets. See www.bnif.co.uk
Consultation results
The UK government has published the result of a consultation
it held on a proposed exemption order under the Radiological Substances
Act 1993 concerning the use of natural gas containing radon-222 and the
levels needed before authorisation is required. Details at www.defra.gov.uk/environment/consult/radgas/response.htm
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