How many reactors are at the Pickering nuclear station?
There are eight reactors at the Pickering nuclear station - four
at the older Pickering 'A' station and four at the Pickering 'B'
station. The four Pickering "A" reactors are the oldest commercial
reactors in the country, and began commercial operation between
1971 and 1973. The four Pickering "B" reactors were added on
between 1983 and 1985, sharing common safety systems (containment
and Emergency Core Cooling) with Pickering "A".
Why should the Pickering Nuclear Station be shut down and not
rebuilt?
The Pickering nuclear station is Canada's most oldest and
dangerous nuclear station, located on the eastern border of
Toronto, Canada's largest city. Pickering is closer than any
other nuclear station in the world. Because of the high
population density, regulatory authorities would not allow a new
plant to be built at Pickering today.
Ontario Power Generation (OPG) has not made an economic case for
building the Pickering B reactors. It would be a risky,
multibillion dollar project. Greenpeace believes these billions of
dollars should be invested in cheaper, safer, cleaner and more
reliable energy options, such as conservation programs and
renewable power.
Why is Ontario Power Generation proposing to rebuild the four
reactors at the Pickering B nuclear station?
The four reactors at the Pickering B nuclear station are ageing
and OPG has admitted that none of the reactors can be operated
safely after 2014.
To extend the life of the four Pickering B reactors, OPG must
carry out what could be called a heart transplant on each of the
reactors. The pressure tubes in the reactor core, or heart of the
reactor - which are highly radioactive - must be disassembled and
either crushed or melted to reduce the volume, and stored in the
new waste storage facility. It must then rebuild a new reactor
core.
Rebuilding the reactors at Pickering B is an complex, expensive
and time-consuming endeavor. Indeed, according to OPG's project
description it will take over 10 years to rebuild all four
reactors.
Can rebuilding the Pickering B nuclear power station reliably
meet Ontario's electricity needs over the next ten to twenty
years?
No. One need only take the example of Pickering A nuclear
station. In 1997, 8 out of Ontario's 20 reactors, including the 4
Pickering A reactors, had to be shut down because of poor
performance and safety problems - the largest nuclear shutdown in
world history. To keep the lights on, Ontario was forced to boost
production at its coal-fired generation stations, increasing
greenhouse gas emissions by 120%.
In 2000, Ontario committed to restart the 4 reactors at the
Pickering A nuclear station. As is the norm with nuclear projects,
the restart of the Pickering reactors underwent a five-fold cost
over-run, increasing from the estimate of $780 million to $4
billion, and underwent numerous delays, leaving the province with
electricity shortages. In August 2005, the McGuinty government
relented and abandoned the restart of final two reactors (units 2
& 3) at Pickering A, citing the high-cost and probable lack of
reliability.
What's the lesson learned? Ontario wasted over 5 years and over
$2 billion trying to rebuild the Pickering A reactors when it could
have invested in other energy options, such as conservation
programmes and renewables to meet our energy needs today.
Unlike a nuclear megaproject, renewable energy options and
conservation can be deployed quickly and contribute to our energy
needs in the near-term and mid-term. Over time, the deployment of
smaller, decentralized green energy options adds up to provide a
cumulative energy punch as big as any nuclear megaproject. Today
Germany has 18,000 MW of wind power while Ontario has about
300MW.
Why is the safety of the Pickering nuclear station a particular
concern?
There are six operating reactors at the Pickering nuclear
station - two at the older Pickering "A" station and four at the
Pickering "B" station.
The four Pickering "A" reactors are the oldest commercial
reactors in the country, and began commercial operation between
1971 and 1973. The four Pickering "B" reactors were added on
between 1983 and 1985.
The Pickering nuclear station has a greater risk of accident
than other stations because the containment and Emergency Core
Cooling System are shared between all reactors at the A and B
stations. In addition, the Pickering "A" reactors are the oldest
commercial reactors in the country, and because of their age are
the only reactors in the western world with only one emergency
shutdown system.
The Pickering station is also closer to larger numbers of people
(Toronto) than any other nuclear plant in the world. For that
reason, regulatory authorities would not allow a new plant to be
built at Pickering today.
What would be the impact of an accident at the Pickering
nuclear station?
In the early morning of April 26 1986, reactor 4 at the
Chernobyl nuclear station exploded, causing what the United Nations
has called "the greatest environmental catastrophe in the history
of humanity." A comparable accident at the Pickering Nuclear
Station would have a disastrous impact on the health and
environment of Southern Ontario and devastate the economy of
Canada's industrial heartland.
Fallout from Chernobyl contaminated over 140,000 square
kilometers, equaling 23% of Belarusian, 5% of Ukrainian, and 1.5%
of Russian territory. As a result, over 1.4 million hectares of
agricultural and forested lands in Russia, Belarus and the Ukraine
have been removed from commercial production since Chernobyl.
Because of radioactive contamination from Chernobyl, over
350,000 people have been forced to permanently relocate, destroying
local economies and communities. The high cost of resettlement,
health care, environmental clean-up and lost agricultural capacity
forced Ukraine and Belarus to introduce a 'Chernobyl tax' in the
1990s.
Just thirty kilometers from downtown Toronto, a similar accident
at the Pickering nuclear station would decimate Canada's largest
city and require the resettlement of several million people.
A 1993 study by Dr. Gordon Thompson of the Institute for
Resource and Security Studies estimated that a severe accident at
the Darlington nuclear station, just east of Toronto, could lead to
200,000 fatalities. He estimated the economic cost of such an
accident would be $1 trillion.
Ontario Power Generation permanently shut down two reactors at
the Pickering A nuclear station August 2005. Why?
After shutting down the 4 Pickering A reactors in 2000, Ontario
committed to restart the Pickering A nuclear reactors at an
estimated cost of $780 million. The restart of the Pickering
reactors underwent a six-fold cost over-run and underwent numerous
delays, leaving the province with electricity shortages and
dependent on increased coal generation. In August 2005, the
McGuinty government relented and abandoned the restart of final two
reactors (units 2 & 3) at Pickering A, citing the high-cost and
probable lack of reliability. It cost $2.5 billion to restart
the first reactors.
The McGuinty government and OPG did not learn the lesson from
Pickering A, however. Just 3 months after abandoning the restart
of two reactors at the Pickering nuclear station, OPG started
planning to risk billions on rebuilding the Pickering B nuclear
station.
How could we replace the electricity produced by Pickering B by
2014?
As the Pickering A fiasco shows, the reconstruction of nuclear
stations is no guarantee of cheap or reliable electricity supply.
Nuclear projects typically undergo cost over-runs and long
delays.
Unlike a nuclear mega-project, however, renewable energy and
conservation can be deployed quickly and contribute to our energy
needs quickly, compared to nuclear mega-projects which take at
least ten years. Over time, smaller, decentralized green energy
options add up to provide a cumulative energy punch as big as any
nuclear mega-project.
The McGuinty government has set a 10% target of installing 2,700
MW of renewable energy by 2010. Countries such as Germany and
Spain, however, are installing over 1,000 MW of renewable power a
year. There's no reason Ontario could not do the same and boost
its renewable energy and conservation targets to compensate for the
loss of Pickering B in 2014.
Is the nuclear industry correct when it says that a
Chernobyl-type accident is "not possible in Canada"?
No. Canada's CANDU nuclear reactor is no safer than any other
reactor design. Human error, terrorist attack or technical
failure could cause a meltdown at any of Canada's nuclear
stations.
Following the accident at the American Three Mile Island nuclear
station in 1979, an all-party committee of the Ontario Legislature
(the Select Committee on Hydro Affairs) investigated Ontario's
nuclear policies. In its 1980 report to the legislature, the
committee concluded that:
"It is not right to say that a catastrophic accident (in a
CANDU reactor) is impossible ... The worst possible accident
could involve the spread of radioactive poisons over large areas,
killing thousands immediately, killing others through increasing
susceptibility to cancer, risking genetic defects that could affect
future generations, and possibly contaminating, for further
habitation, large land areas...
Accidents, mistakes and malfunctions do occur in [CANDU] nuclear
plants: equipment fails; instrumentation gives improper readings;
operators and maintainers make errors and fail to follow
instructions; designs are inadequate; events that are considered
`incredible' happen...no matter how careful we are, we must
anticipate the unexpected."
Is the nuclear industry confident that a nuclear accident will
never happen in Canada?
No. Despite nuclear industry claims that a Chernobyl-type
accident is "not possible in Canada," the nuclear industry requires
special financial liability protection from the federal government
in case of a major nuclear accident. The federal Nuclear Liability
Act limits that amount of financial liability of any nuclear
reactor operator to $75 million - a miniscule fraction of the
likely actual cost of a nuclear disaster.
Premier McGuinty says it is "irresponsible" to say that
Chernobyl-type accident could happen in Canada because of "Canada's
Candu technology." Is he right?
No. CANDU reactors also share the following similarities with
the RBMK reactors at Chernobyl:
1. Ontario's nuclear stations and Chernobyl are four-reactor
stations with shared safety systems. Sharing of safety systems
reduces redundancy and increases the risk of radiation release.
2. Both reactor designs employ fuel channels (as opposed to one
large pressurized reactor vessel), including pressure tubes made of
the same alloy. These tubes incorporate hydrogen over time, causing
tubes to become brittle and breakable.
3. While most reactors have to be shut down every year or two
for refuelling, CANDU and RBMK reactor designs allow for on-line
refuelling. This has the potential to improve performance, but it
also can increase the length of time without inspection or
maintenance. Chernobyl reactor 4 had been operating for over two
years non-stop when it exploded on April 26 1986.
4. CANDU is the only reactor design outside the former Soviet
Union, that like the RBMK, has a positive void effect. Steam
formation in the reactor core increases reactivity (more nuclear
fissions taking place), increasing power levels, causing more steam
formation and resulting in a loss of regulation accident.
What have other countries done to avoid a Chernobyl-type
accident?
In 2000, Germany committed to phasing out nuclear power and
phasing in clean, green renewable energy. Germany's
then-Environment Minister Jurgen Trittin said that phasing out
nuclear power was "a logical response to Chernobyl."
In a referendum following Chernobyl accident, Italy voted to
abandon nuclear power completely in 1987. Italy subsequently
closed all of its reactors and placed a moratorium on the
construction of new nuclear stations.
Are airplane crashes or terrorist attacks a concern at the
Pickering nuclear station?
Yes. The federal government is proposing to build an
international airport in Pickering and September 11th revealed that
all of Canada's nuclear stations are vulnerable to a terrorist
attack.
It is noteworthy that after the September 11th, the Nuclear
Insurance Association of Canada refused to provide coverage for
potential terrorist incidents at nuclear stations for such things
as air plane crashes. The insurance industry has acknowledged and
is accounting for the potential for a terrorist attack at Canada's
nuclear stations.
Have accidents happened at the Pickering nuclear station?
Yes. There have been a number of near misses at the Pickering
nuclear station.
The following is a selection of these accidents:
-
Accidents at Pickering Nuclear
- Pickering Reactor 2, August 1, 1983
- A metre-long break ruptured a pressure tube in Pickering
Reactor 2, spilling 17 kg of heavy water per second onto the floor
of the reactor vault. The leak rate was gradually reduced as the
coolant pressure dropped, and the the leak was stopped two weeks
later. A broken fuel bundle left fuel 'pencil' wedged in the crack,
which greatly complicated the removal of the pressure tube.
Inspection of the pressure tubes at reactor 1 showed similar
degradation, which resulted in the early retubing of Pickering
reactors 1 and 2.
- Pickering Reactor 1, November 22, 1988
- A fuel failure occurred when a Pickering Reactor 1 operator,
working with incorrect operating instructions, increased reactor
power from 65% to 87%, causing 36 fuel bundles to fail. The
breakdown of fuel bundles in the core was revealed by a sudden
increase in the level of radioactive isotope iodine-131. Iodine-131
levels were at 30 times the normal release levels in the last two
weeks of December 1988, and 80 times the normal release levels in
the first week of January 1989. Ontario Hydro continued to operate
the reactor and attempted to remove and damaged fuel bundles
between January and May 1989.
- Pickering Reactor 2, March 1989
- Workers discovered that a 100 square cm hole had existed
between the moderator purification room and the moderator room
since early 1988. If a serious loss of coolant accident had
occurred at some point during those fifteen months, the resulting
leakage of water between these two rooms would have damaged the
sump pumps, which are required to recirculate water to the
Emergency Core Cooling System during a Loss of Coolant
Accident.
- Pickering Reactor 2, September 25, 1990
- Pickering Reactor 2 experienced a "severe flux tilt" (unstable
and unbalanced nuclear fission) following the insertion of an
adjustor rod into the core Operators spent two days trying to
stabilize the reactor by changing fuel bundles, reactor power and
the configuration of the adjustor rods. The station management was
reprimanded by the Atomic Energy Control Board for not shutting the
reactor down right away. A second flux tilt occurred at the same
reactor in November 1990, only two months later.
- Pickering Reactor 4, November 1990
- Moderator room pumps were found seized up at Pickering reactor
4. This situation was estimated to have disabled the Emergency Core
Cooling System of that reactor for the previous 11 months. Had a
Loss of Cooling Accident occurred during that time, the pumps would
not have performed their crucial function of recirculating the
water to the Emergency Core Cooling System to keep the fuel from
melting.
- Pickering "A" and "B", 1990
- During a test of the containment system at Pickering that is
carried out only once every ten years, a seal on the Pressure
Relief Duct failed at about one half the pressure it was designed
to withstand. It was estimated that containment at the Pickering
site was inadequate for 7.5 years prior to the test which revealed
the weak seal. Work on the seals was not completed until June 1995.
This could have allowed serious radiation releases in the event of
an accident.
- Pickering Reactor 4, June 1991
- A faulty valve on a steam generator resulted in a 15,000 litre
leak of heavy water at reactor 3. the reactor was just being
re-started following retubing work carried out over the previous
two years. While it was reported that no water leaked out of the
steam generator area into Lake Ontario, there were airborne
releases of tritium (a radioactive form of hydrogen) in the four
hours immediately following the accident.
- Pickering Reactor 1, August 2 1992
- A heat exchanger was damaged by debris from a broken strainer,
spilling over 2,000 litres of radioactive heavy water into Lake
Ontario. The spill began at about 1:30 a.m. and lasted for 6 hours.
The problem was not noticed by Ontario Hydro staff until 4:50 a.m.,
and was not stopped for an additional one and a half hours.This was
the largest single tritium spill ever to occur at Pickering.
Sampling of local drinking water for tritium revealed significant
increases, despite dilution over four days and the five kilometers
of waterfront between the Pickering reactors and the Ajax water
supply facility, the closest municipal water intake. The Ajax water
plant was not shut down at the time, and the public was not
notified, so those at most risk (pregnant women and young children)
did not have the option of avoiding contaminated drinking
water.
- Pickering Reactor 4, April 15, 1996
- A leaking heat exchanger spilled 100 litres of radioactive
heavy water into Lake Ontario. The leak was discovered at 9:40 p.m.
and was halted two hours later at 11:50 p.m. As a result of the
spill, Durham Region shut down Ajax water treatment plant for about
24 hours.Pickering Stations A and B, April 16, 1996
- Workers discovered a malfunctioning valve associated with the
Emergency Core Cooling System. After delaying several days (while
former Prime Minister Chrétien was promoting CANDU reactors in
Eastern Europe), Ontario Hydro announced the first unscheduled
shutdown of all eight reactors at both Pickering nuclear stations.
The shutdown took place on April 20 and 21. Hydro said that it
expected to take about ten days to repair the safety
system.Pickering Nuclear Station, August 14, 2003 - At the time of
the great blackout in eastern North America on August 14, 2003, the
Pickering B reactors # 5, 6 and 8 were operating at or near full
power and reactor # 7 was being restarted following a planned
maintenance outage. Pickering A reactor # 4 was just being started
up after being shut down since 1997, and was operating at 12%
power, but was not synchronized to the grid.A significant design
flaw in the Pickering station's emergency shutdown system was
underscored by the blackout. The U.S.-Canada Power System Outage
Task Force noted that "[e]quipment problems and design limitations
at Pickering B resulted in a temporary reduction in the
effectiveness of some of the multiple safety barriers…".Most
notably, the Pickering station's Emergency Core Cooling System
(ECCS), which is used in the case of a Loss of Coolant Accident was
designed to operate from grid supplied electricity. When the
Pickering nuclear station was disconnected from the grid, the ECCS
was unavailable for approximately 5.5 hours, meaning that it would
have been impossible to replace coolant if a Large Loss of Coolant
Accident (LLOCA) had occurred during that time.Several emergency
low pressure and high pressure water pumps used for cooling also
failed to operate as intended. Operators were required to intervene
manually to ensure safe shutdown. Because of the serious problems
with the ECCS during the blackout, Canadian Nuclear Safety
Commission staff rated the emergency shutdown of the Pickering
station as a Level 2 incident on the International Nuclear Event
Scale. Pickering B, December 26, 2003 - It was discovered Emergency
Core Cooling System would have been unavailable in the case of a
Loss of Coolant Accident (LOCA) and Loss of Electricity Supply
(LOBES) incident because of a problem with the Site Electrical
System. The system was unavailable for 7 hour and 38 minutes.