Major Safety Flaws Uncovered at Torness Plant Nuclear Watchdog Slams 'Ignorance' and Cuts
Jun 27 - Sunday Herald
AN accident at Torness nuclear power station in 2002, described at the time by British Energy as ''vibration problems'', was far more serious and highlighted major flaws in safety procedures, according to a nuclear watchdog report finally released last week.
Some of the information the company provided to investigators was said to be
"inaccurate or inconsistent".
The accident - one of the worst in the history of Torness - led to one
reactor being shut down for more than six months, and cost British Energy at
least pounds-25 million.
The NII's investigation report, which has been kept secret until now, gives
the first full account of what happened.
The NII's most damning criticism is reserved for the fact that it took
British Energy nearly three weeks to produce a safety assessment of the accident
and to launch a formal inquiry. This was "too slow", the report
concludes, "and doesn't demonstrate that a high priority is given to
nuclear safety".
At the time, British Energy described the accident to shareholders as simply
"vibration problems in one gas circulator". However, the official
description of events that emerges from the NII report is less comforting.
Operators made a serious mistake and vital machinery meant to keep the
reactor cool was badly damaged. A series of alarms sounded, a temperature gauge
went "off-scale" and 750 litres of oil went missing.
The accident began at 8.13pm on Friday May 10, 2002, when Torness reactor two
automatically shut down because it detected a flaw in its cooling system.
The reactors need to be constantly cooled to prevent them from overheating
and leaking radioactivity.
The workers on shift called in a maintenance engineer and two computer
specialists to help work out what had gone wrong. Maintenance engineers had been
removed from shifts "as part of the staff-reduction/ cost-saving
process", the NII report states.
By 2.45am on Saturday, the problem was judged to have been caused by a faulty
circuit breaker. In order to test the theory staff decided to restart a gas
circulator - which is when things went badly awry.
Within three seconds they "heard a loud noise accompanied by heavy
vibration" and the circulator was hastily turned off again. It was later
found to have suffered significant "deformation", "possible drive
shaft failure" and to have scattered many loose parts.
The decision to restart the circulator in an unfamiliar situation "was
not obviously conservative", the NII says.
"The operators' ignorance of the local plant vibration monitoring system
is not acceptable and there seems to be little attention afforded to vibration
alarms generated." Communication between maintenance and operations
divisions was judged to be poor, and vital information about the accident could
have been lost, the report observes. "Some information provided to NII by
the station within the opening session of the investigation was inaccurate or
inconsistent with later discussions, " it states.
The NII report was released to the Green MSP and speaker on nuclear issues,
Chris Ballance, in response to a request under the Freedom of Information Act.
He accused the nuclear industry of trying to "whitewash" the
seriousness of the accident.
"This was a major accident caused by incompetence, attempts to cut costs
and a disregard of health and safety training, " Ballance told the Sunday
Herald.
"We are very lucky that the damage did not spread to the nuclear reactor
core.
"It demonstrates the folly in trusting nuclear power to keep the lights
on.
"It is intrinsically unreliable, and its fundamentally uneconomic nature
causes nuclear operators to try and cut costs, with real and frightening safety
implications." Ballance is backed by environmentalists, who compared the
accident at Torness with a breakdown that closed a controversial nuclear
reprocessing plant at Sellafield in Cumbria in April.
"How can we believe the nuclear industry's claim to be the answer to
climate change when its plants keep breaking down?" asked Pete Roche, a
nuclear consultant to Greenpeace.
"The Torness accident was clearly more worrying than we thought at the
time. It suggests that acute commercial pressures may have forced British Energy
to compromise on safety." British Energy, however, strongly denied that the
public had been put in any danger. "At no time would we risk the safety of
the community, the public or our workforce, " said the company's
spokeswoman.
"Even when economic pressures are substantial, we will not compromise
safety. Nuclear safety remains our main priority." She pointed out that
British Energy had responded to all the concerns raised by the NII and had
reassured the body that Torness reactor two was safe to restart on November 30,
2002. More sensitive vibration monitoring equipment has since been installed and
gas circulators are now inspected more frequently.
"We've learnt from this because we don't want it to happen again, "
the spokeswoman added. "Financially, this was a real blow to the
company."