Chalk River Laboratories (French: Laboratoires de Chalk River; also known as CRL, Chalk River
Labs and formerly Chalk River Nuclear Laboratories) is a Canadian nuclear research facility in
Deep River, Renfrew County, Ontario, near Chalk River, about 180 km (110 mi) north-west
of Ottawa.
CRL is a site of major research and development to support and advance nuclear technology,
in particular CANDU reactor technology.
CRL has expertise in physics, metallurgy, chemistry, biology, and engineering and unique
research facilities.
For example, Bertram Brockhouse, a professor at McMaster University, received the 1994
Nobel Prize in Physics for his pioneering work in neutron spectroscopy while at CRL
from 1950-1962.
Sir John Cockcroft was an early director of CRL and also a Nobel laureate.
CRL produces a large share of the world's supply of medical radioisotopes.
It is owned by the Canadian Nuclear Laboratories subsidiary of Atomic Energy of Canada Limited
and operated under contract by the Canadian National Energy Alliance, a private-sector
consortium led by SNC-Lavalin.
== History == The facility arose out of a 1942 collaboration
between British and Canadian nuclear researchers which saw a Montreal research laboratory established
under the National Research Council (NRC).
By 1944 the Chalk River Laboratories were opened and in September, 1945 the facility
saw the first nuclear reactor outside of the United States become operational (see Lew
Kowarski).
In 1946, NRC closed the Montreal laboratory and focused its resources on Chalk River.
In 1952, Atomic Energy of Canada Limited (AECL) was created by the government to promote peaceful
use of nuclear energy.
AECL also took over operation of Chalk River from the NRC.
Throughout the 1950s-2000s various nuclear research reactors have been operated by AECL
for production of nuclear material for medical and scientific applications.
The Laboratories produce about one-third of the world's medical isotopes, and about half
of the North American supply.
Despite the declaration of peaceful use, from 1955 to 1976, Chalk River facilities supplied
about 250 kg of plutonium, in the form of spent reactor fuel, to the U.S. Department
of Energy to be used in the production of nuclear weapons.
(The bomb dropped on Nagasaki, Japan, used about 6.4 kg of plutonium.)
Canada's first nuclear power plant, a partnership between AECL and Hydro-Electric Power Commission
of Ontario, went online in 1962 near the site of Chalk River Laboratories.
This reactor, Nuclear Power Demonstration (NPD), was a demonstration of the CANDU reactor
design, one of the world's safest and most successful nuclear reactors.
The Deep River neutron monitor operated once in Chalk river.
=== 1952 NRX incident === Chalk River was also the site of two nuclear
accidents in the 1950s.
The first incident occurred in 1952, when there was a power excursion and partial loss
of coolant in the NRX reactor, which resulted in significant damage to the core.
The control rods could not be lowered into the core because of mechanical problems and
human errors.
Three rods did not reach their destination and were taken out again by accident.
The fuel rods were overheated, resulting in a meltdown.
The reactor and the reactor building were seriously damaged by hydrogen explosions.
The seal of the reactor vessel was blown up four feet.
In the cellar of the building, some 4,500 tons of radioactive water was found.
This water was dumped in ditches around 1600 meters from the border of the Ottawa River.
During this accident some 10,000 curies or 370 TBq of radioactive material was released.
Future U.S. president Jimmy Carter, then a U.S. Navy officer, was part of the cleanup
crew.
Two years later the reactor was in use again.
=== 1958 NRU incident === The second accident, in 1958, involved a fuel
rupture and fire in the National Research Universal reactor (NRU) reactor building.
Some fuel rods were overheated.
With a robotic crane, one of the rods with metallic uranium was pulled out of the reactor
vessel.
When the arm of the crane moved away from the vessel, the uranium caught fire and the
rod broke.
The largest part of the rod fell down into the containment vessel, still burning.
The whole building was contaminated.
The valves of the ventilation system were opened, and a large area outside the building
was contaminated.
The fire was extinguished by scientists and maintenance men in protective clothing running
along the hole in the containment vessel with buckets of wet sand, throwing the sand down
at the moment they passed the smoking entrance.Both accidents required a major cleanup effort
involving many civilian and military personnel.
Follow-up health monitoring of these workers has not revealed any adverse impacts from
the two accidents.
However, the Canadian Coalition for Nuclear Responsibility, an anti-nuclear watchdog group,
notes that some cleanup workers who were part of the military contingent assigned to the
NRU reactor building unsuccessfully applied for a military disability pension due to health
damages.Chalk River Laboratories remain an AECL facility to this day and are used as
both a research (in partnership with the NRC) and production facility (on behalf of AECL)
in support of other Canadian electrical utilities.
=== 2007 shutdown === On November 18, 2007, the NRU, which makes
medical radioisotopes, was shut down for routine maintenance.
This shutdown was extended when AECL, in consultation with the Canadian Nuclear Safety Commission
(CNSC), decided to connect seismically-qualified emergency power supplies (EPS) to two of the
reactor's cooling pumps (in addition to the AC and DC backup power systems already in
place), which had been required as part of its August 2006 operating licence issued by
the CNSC.
This resulted in a worldwide shortage of radioisotopes for medical treatments because Chalk River
makes the majority of the world's supply of medical radioisotopes, including two-thirds
of the world's technetium-99m.On December 11, 2007, the House of Commons of Canada,
acting on independent expert advice, passed emergency legislation authorizing the restarting
of the NRU reactor and its operation for 120 days (counter to the decision of the CNSC),
which was passed by the Senate and received Royal Assent on December 12.
Prime Minister Stephen Harper criticized the CNSC for this shutdown which "jeopardized
the health and safety of tens of thousands of Canadians", insisting that there was no
risk, contrary to the testimony of then CNSC President & CEO Linda Keen.
She would later be fired for ignoring a decision by Parliament to restart the reactor, reflecting
its policy that the safety of citizens requiring essential nuclear medicine should be taken
into account in assessing the overall safety concerns of the reactor's operation.
The NRU reactor was restarted on December 16, 2007.
=== 2008 radioactive leakage === On December 5, 2008, heavy water containing
tritium leaked from the NRU.
The leaked water was contained within the facility, and the Canadian Nuclear Safety
Commission (CNSC) was notified immediately, as required.
In its formal report to the CNSC, filed on December 9, 2008 (when the volume of leakage
was determined to meet the requirement for such a report) AECL mentioned that 47 litres
of heavy water were released from the reactor, about 10% of which evaporated and the rest
contained, but affirmed that the spill was not serious and did not present a threat to
public health.
The amount that evaporated to the atmosphere is considered to be minor, accounting for
less than a thousandth of the regulatory limit.
The public was informed of the shutdown at the reactor, but not the details of the leakage
since it was not deemed to pose a risk to the public or environment.
The leak stopped before the source could be identified, and the reactor was restarted
on December 11, 2008 with the approval of the CNSC, after a strategy for dealing with
the leak (should it reappear) was put in place.
In an unrelated incident, the same reactor had been leaking 7,001 litres of light water
per day from a crack in a weld of the reactor's reflector system.
This water has been systematically collected, purified in an on-site Waste Treatment Centre,
and eventually released to the Ottawa River in accordance with CNSC, Health Canada, and
Ministry of the Environment regulations.
Although the leakage is not a concern to the CNSC from a health, safety or environmental
perspective, AECL has plans for a repair to reduce the current leakage rate for operational
reasons.
=== 2009 NRU reactor shutdown ===
In mid-May 2009 the heavy water leak at the base of the NRU reactor vessel, first detected
in 2008 (see above), returned at a greater rate and prompted another temporary shutdown
that lasted until August 2010.
The lengthy shutdown was necessary to first completely defuel the entire reactor, then
ascertain the full extent of the corrosion to the vessel, and finally to effect the repairs
— all with remote and restricted access from a minimum distance of 8 metres due to
the residual radioactive fields in the reactor vessel.
The 2009 shutdown occurred at a time when only one of the other four worldwide regular
medical isotope sourcing reactors was producing, resulting in a worldwide shortage.
== NRU shutdown in March 2018 == The NRU reactor licence expired in 2016, however
the licence was extended to March 31 2018.
The reactor went was shut down for the last time at 7 p.m. on 31 March 2018 and has entered
a "state of storage" prior to decommissioning operations which will continue for many years
within the scope of future operating and/or decommissioning licences issued by the CNSC.
== Major facilities == ZEEP — Zero Energy Experimental Pile Reactor
(1945–1973).
NRX — NRX Reactor (1947–1992).
NRU — National Research Universal 135 MWt Reactor (1957–2018).
CNBC — Canadian Neutron Beam Centre PTR — Pool Test 10 kW Reactor (1957–1990).
ZED-2 — Zero Energy Deuterium 200W Reactor (1960–).
NPD — Nuclear Power Demonstration 20MW(e) reactor; located north of CRL in Rolphton,
Ontario (1960–1987).
SLOWPOKE — Safe Low-Power Kritical Experiment 5 kW Reactor (1970–1976) — moved to the
University of Toronto in 1971.
TASCC — Tandem Accelerator Superconducting Cyclotron (1986–1996)
MAPLE-1 — Multipurpose Applied Physics Lattice Experiment Reactor (2000–2008; canceled).
MAPLE-2 — Multipurpose Applied Physics Lattice Experiment Reactor (2003–2008; canceled).
CRIPT — Cosmic Ray Inspection and Passive Tomography
== See also ==
George Laurence Lew Kowarski
Science and technology in Canada Petten nuclear reactor, a nuclear reactor
in the Netherlands that produces Europe's supply of isotopes for nuclear medicine
Nuclear power in Canada CANDU reactor
Atomic Energy of Canada Limited Manhattan Project
== Further reading ==
Robert Bothwell, "Nucleus.
The History of Atomic Energy of Canada Limited", University of Toronto Press, 1988.
http://www.cnl.ca/en/home/default.aspx