sent in as SELLAFIELD Admits to serious safety Lapses
Independent, 14 September 1999
NUCLEAR Installations Inspectorate, the official watchdog on nuclear
safety, is to visit Sellafield [today] after an admission by officials
at the plant of serious "irregularities" in the manufacture of highly
dangerous nuclear fuel rods destined for export.
investigation follows claims made to The Independent that safety checks
on the fuel rods have been "falsified".
The problem concerns the production of uranium
and plutonium mixed-oxide (MOX) fuel rods on an assembly line at British
Nuclear Fuels"(BNFL) plant in Cumbria. Each rod contains more than
1,000 cylindrical pellets and about 200 pellets in each rod have to
be routinely sampled and measured at three points to check they are
the correct size.
a source at the plant told The Independent that some of these checks
may have been faked. To save time, some employees bypassed quality-
control checks by using data sheets from previous samples. Thus some
batches of rods were passed as safe when they had not been checked at
MOX fuel is a highly dangerous substance. It receives
the highest security classification and each consignment is shipped
in armoured vehicles with armed escorts.
BNFL insisted yesterday that the irregularities
it had found did not affect any of the assemblies now being sent to
Japan on board two ships. But at least 10 lots have been found to have
been falsified, according to the source. He added: "If the pellets are
larger than they should be, they can expand and damage the cladding
of the fuel rod. If they are too small, they can vibrate and the pellets
The admission could not come at a more sensitive
time for BNFL. It is preparing for a pounds 1bn privatisation and has
applied for permission to open a new and highly controversial MOX facility
costing pounds 300m. The future of the whole industry is dependent on
the success of MOX manufacture and shipment to countries such as Japan,
which is planning to run up to 18 reactors on the fuel by 2010. BNFL
and its French partner, Cogema, are banking on 70 MOX reactors being
run worldwide within 11 years.
Ed Lyman, scientific director of the Nuclear Control
Institute in Washington DC, said that if true, the allegations would
have serious safety implications for reactors loaded with the defective
MOX fuel. "Clearly this is very important for Japan," he said. Japan's
custom is the key to BNFL's ambitions to expand its activities to the
new plant at Sellafield, which is expected to produce more than 100
tons of the fuel each year, Dr Lyman said.
hint that the fuel would be defective would lead to a serious re- evaluation
because the shipment would have to be sent back and refabricated at
enormous cost," he added.
a statement to The Independent, BNFL said: "Some irregularities in data
have been detected during the quality- control checks on MOX fuel currently
being manufactured. Measures have been taken to address the issue."
The company said all MOX fuel assemblies on the way to Japan have been
fully certified. "Some fuel for additional assemblies is being prepared
at this moment, and this fuel has not yet been certified," the spokesman
When asked to explain the nature of the irregularities,
he said: "It is an irregularity in the data. They are not quite as we
would have expected them so we've gone back and had another look to
see how they might have arisen, and we are trying to put in place measures
to make sure it is dealt with accordingly."
A spokesman for the Nuclear Installations Inspectorate
said: "We've been informed of irregularities in the implementation of
procedures for checking the size of MOX pellets for export."