History
1940s
AECL traces its heritage to the Second World War when a joint Canadian-British nuclear research laboratory was established in Montreal in 1942, under the National Research Council of Canada to develop a design for a nuclear reactor. In 1944, approval was given by the federal government to begin with construction of the ZEEP (Zero Energy Experimental Pile) reactor at the Chalk River Nuclear Laboratories near Chalk River, Ontario, located on the Ottawa River approximately 190 km northwest of Ottawa. AECL was also involved in the development of associated technology such as the UTEC computer.
On September 5, 1945 the ZEEP reactor first went critical, achieving the first "self-sustained nuclear reaction outside the United States." ZEEP put Canada at the forefront of nuclear research in the world and was the instigator behind eventual development of the CANDU reactors, ZEEP having operated as a research reactor until the early 1970s.
In 1946 the Montreal research laboratory was closed and research was consolidated at Chalk River Laboratories. On July 22, 1947 the NRX (National Research Experimental) reactor, the most powerful reactor in the world at the time, went critical and was "used successfully for producing radioisotopes, undertaking fuels and materials development work for CANDU reactors, and providing neutrons for physics experiments."
1950s
In 1952 AECL was formed by the government with a mandate to develop peaceful uses of nuclear energy.
On December 12, 1952 one of the world's first major reactor accidents occurred in the NRX reactor at AECL's Chalk River Laboratories, when a combination of human and mechanical error led to a temporary loss of control over the reactor's power level. Undercooling of the fuel channels led to a partial meltdown. This caused a hydrogen-oxygen explosion inside the calandria. Several fuel bundles experienced melting and ruptured, rendering much of the core interior unusable. The reactor building was contaminated, as well as an area of the Chalk River site, and millions of gallons of radioactive water accumulated in the reactor basement. This water was pumped to a waste management area of the Laboratories and monitored. Hundreds of military personnel from Canada and the U.S. (including naval officer and later U.S. President, Lt. James "Jimmy" Carter) were employed in the cleanup and disposal of the reactor debris.
The NRX was repaired, upgraded, and returned to service 14 months later and operated for another 40 years, finally being shut down in 1992. Throughout the 1950s the NRX was used by many researchers in the pioneering fields of neutron condensed matter physics, including Dr. Bertram Brockhouse, who shared the 1994 Nobel Prize in Physics for his work in developing the neutron scattering techniques.
On November 3, 1957 the NRU (National Research Universal Reactor) first went critical. This is a natural-uranium, heavy-water-moderated and heavy-water-cooled research reactor which is a world-renowned research facility, producing about 60% of the world's supply of molybdenum-99, the principle isotope used for nuclear medical diagnosis. Canada also pioneered use of Cobalt-60 for medical diagnosis in 1951 and currently the NRU reactor produces the medical-use Cobalt-60, while selected CANDU reactors produce industrial-use Cobalt-60, comprising 85% of the world's supply. NRU was primarily a Canadian design, and a significant improvement on NRX.
On May 24, 1958 the NRU suffered a major accident. A damaged uranium fuel rod caught fire and was torn in two as it was being removed from the core, due to inadequate cooling. The fire was extinguished, but not before releasing a sizeable quantity of radioactive combustion products that contaminated the interior of the reactor building and, to a lesser degree, an area of the surrounding laboratory site. Over 600 people were employed in the clean-up.
A few men were over-exposed to radiation, but no direct injuries resulted from AECL's two accidents.
1960s
In 1954 AECL partnered with the Hydro-Electric Power Commission of Ontario to build Canada's first nuclear power plant at Rolphton, Ontario, which is 30km upstream from Chalk River. On June 4, 1962 the NPD (Nuclear Power Demonstration) first reactor went critical to demonstrate the CANDU concept, generating about 20 MWe. In 1963, AECL established the Whiteshell Nuclear Research Establishment (now Whiteshell Laboratories) in Pinawa, Manitoba where an organic-cooled and organic-operated research reactor was built. Later work on developing a Slow Poke reactor, Thorium Fuel Cycle, and a proposal for safe storage of Nuclear waste were carried out at this site.
AECL built a larger CANDU prototype (200 MWe) at Douglas Point on Lake Huron, first going critical on November 15, 1966. Douglas Point experienced significant problems with leakage of heavy water, which were eventually solved by much-improved valve design. Other important design refinements worked out at Douglas Point opened the way for upscaling to commercial power CANDU reactors in subsequent years.
1970s
In 1971 the first commercial CANDU reactor, Pickering A 1, began commercial operation. By 1973 the other three reactors of the A group at Pickering were online and constituted the most powerful nuclear facility in the world at that time. Each Pickering unit produces about 600 MWe of power.
On May 18, 1974, India detonated a nuclear bomb made from plutonium manufactured by the CIRUS research reactor built by AECL in 1956, which was a commercial version of its NRX research reactor. In addition AECL built two power reactors in India based on the Douglas Point design, and many of India's other reactors are domestic variants of this design. The connection between India's nuclear weapons program and its CIRUS research reactor led to a severance of nuclear technological cooperation between Canada and India.
In 1977-1978 the Bruce A group went online and began commercial operation. Each Bruce unit produces about 800 MWe of power. In 1978, Whiteshell Labs began research into fuel waste disposal.
1980s
Between 1983 and 1986, the Pickering B group went online and also in 1983 the single CANDU reactor at Point Lepreau began operation, as did the Gentilly 2 CANDU reactor. Between 1984-1987 the Bruce B group began commercial operation, and also in 1987 the CANDU design was ranked one of Canada's top-10 engineering achievements.
Douglas Point was decommissioned in May, 1984.
Between 1985 and 1987, a series of design flaws in AECL's Therac-25 medical accelerator caused massive overdoses of radiation on 6 different occasions, resulting in five deaths. In 1987 the machine was found defective by the Food and Drug Administration (FDA) and recalled by AECL.
1990s
Between 1990 and 1993, the 4 CANDU reactors at Darlington went online and represent the most recent reactor construction in Canada.
In 1991, AECL decided to spin-off its medical isotope production business under the name Nordion International Inc. The unit was sold to MDS Health Group and now operates under the name MDS Nordion
With a contract signed in 1991, AECL, in partnership with MDS Nordion, began construction of the MAPLE dedicated isotope-production facility. Constructed on-site at AECL's Chalk River Laboratories this facility will house two reactors and an isotope processing facility. Each reactor is designed to be able to produce at least 100% of the world's medical isotopes, meaning that the second reactor will be used as a back-up to ensure an uninterupptable supply. Although slated to be commissioned in 2000, construction and licensing delays have so far prevented the facility from opening (As of June, 2005).
Unit 1 of the Cernavodă Nuclear Power Plant was commissioned on December 2, 1996. Rated at 706 MWe, it currently supplies approximately 10% of Romania's electrical needs. Unit Two achieved criticality on 6 May 2007 and was connected to the national grid on 7 August. It began operating at full capacity on 12 September 2007, also producing 706 MW.
In the late 1990s, several reactors were built by AECL in South Korea. Wolsong 2 was commissioned July 1, 1997. Wolsong 3 was commissioned on July 1, 1998. Wolsong 4 was commissioned October 1, 1999. All three reactors were rated at 715MWe Gross Output. They currently have some of the highest lifetime capacity factors of nuclear reactors.
2000s - present
In 2001, AECL began tests at Chalk River Labs to determine the feasibility of using surplus MOX (mixed oxide) fuel from the Russian and U.S. defence programs (which contains plutonium) as a fuel in CANDU facilities.
Currently, AECL is developing the Advanced CANDU Reactor, or "ACR". This design is meant to improve the commercial CANDU 6 design in terms of capital cost and construction schedule, while maintaining the classic design and safety characteristics of the CANDU concept.
Cernavoda Nuclear Power Plant Unit 2 began operation on May 6, 2007. Preparatory work required for the completion of Units 3 and 4 is scheduled to begin by the end of 2007.
The Province of Ontario has announced plans to build a new nuclear station. The leading candidate is AECL's Advanced CANDU Reactor. Environmental assessments are currently underway at Bruce Power's Bruce Nuclear Generating Station in Tiverton and a site next to Ontario Power Generation's Darlington Nuclear Generating Station.
Company president Robert Van Adel has announced that he will be stepping down from the position of president and retire from the company effective November 11, 2007.
Energy Alberta Corporation announced August 27, 2007 that they had filed application for a license to build a new nuclear plant at Lac Cardinal (30 km west of the town of Peace River. The application would see an initial twin AECL ACR-1000 plant go online in 2017, producing 2.2 gigawatt (electric).
Point Lepreau, New Brunswick Candu 6 plant refurbishment to begin as of April 1, 2008.
Funding deficiencies, safety concerns, political developments
NRU safety concerns created a political firestorm in December 2007. AECL extended a planned maintenance outage to complete the installation of safety upgrades, after the Canadian Nuclear Safety Commission (CNSC) confirmed that AECL was out of compliance with its operating licence (granted by the CNSC in August 2006) by not having these safety upgrades completed. It became clear that a misunderstanding had taken place between AECL and the CNSC regarding whether the completion of these safety upgrades was, in fact, a licence condition in the first place. The misunderstanding was partly due to the fact that several communications between AECL and the CSNC in the time period 2005-2007 accurately describe the incomplete nature of the safety upgrades, up to and after the granting of the August 2006 licence.
The one-month shutdown of NRU created a shortage of medical radioisotopes; Canada produces about 60 per cent of the world's supply. Parliament passed emergency legislation, winning all-party support, to order the reactor to be restarted, and NRU resumed operations on December 16, 2007.
Subsequently, federal Conservative Energy and Natural Resources Minister Gary Lunn indicated in a letter that he wished to fire CNSC chair Linda Keen over the matter. The Ottawa Citizen obtained and published Lunn's letter to Keen on January 8, 2008. Keen responded by going public with her own criticism of Lunn, publishing a letter on CNSC's website on January 9. Canadian media further developed the story.
Under the Financial Administration Act, AECL and other federal Crown corporations are subject to a special examination by the Auditor General of Canadaonce every five years. In September 2007, the Office of the Auditor General of Canada submitted a special examination report to AECL's board of directors, indicating also that the report would be provided to Natural Resources Minister Gary Lunn, who oversees AECL at the political level. Fraser's report pinpointed serious government funding deficiencies for AECL, which had held back necessary expansion, upgrading, and replacement of its facilities. Opposition politicians defended Keen, called for Lunn to be fired, and for the report to be made public (Auditor-General's report identified 'deficiency' at AECL, by Juliet O'Neill, The National Post, January 10, 2008, p. A1).
Prime Minister Stephen Harper backed Lunn, (http://www.theglobeandmail.com, January 10, 2008). and Linda Keen was dismissed as chair of the CNSC at 10pm Tuesday January 15 - 12 hours before she was to appear before a Commons committee. She remains a member of the CNSC board. EdmontonSun, CBC News
On January 29, 2008, the former President of the CNSC, Linda Keen, testified before a Parliamentary Committee that the risk of fuel failure in the NRU reactor was "1 in 1000", and claimed this risk to be a thousand times greater than the "international standard of 1 in one million". These claims are refuted by AECL.
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