Canada's Nuclear History Chronology

Updated November 25, 2009

I try to ensure accuracy in this chronology and notes.   Please let me know of any errors, dead or changed links, or other dates that should be included. Initials in curly braces are sources.

Morgan Brown, P. Eng.

Reference books on Canada's nuclear history:
Canada's Nuclear Story

Canada's Nuclear Story
by Wilfrid Eggleston, Clarke Irwin, 1965

Eldorado: Canada's National Uranium Company

Eldorado: Canada's National Uranium Company
by Robert Bothwell, University of Toronto Press, 1984

Nucleus: The History of Atomic Energy of Canada Limited

Nucleus: The History of Atomic Energy of Canada Limited
by Robert Bothwell, University of Toronto Press, 1988

Nuclear Pursuits: the scientific biography of Wilfrid Bennett Lewis

Nuclear Pursuits: the scientific biography of Wilfrid Bennett Lewis
by Ruth Fawcett, McGill-Queen's University Press, 1994

Canada Enters the Nuclear Age: a technical history of Atomic Energy of Canada Limited as seen from its research laboratories

Canada Enters the Nuclear Age:
a technical history of Atomic Energy of Canada Limited as seen from its research laboratories

Edited by Don Hurst, McGill-Queen's University Press, 1997

Isotopes and Innovation; MDS Nordion's First Fifty Years, 1946 - 1996

Isotopes and Innovation:
MDS Nordion's First Fifty Years, 1946 - 1996

by Paul Litt, McGill-Queen's University Press, 2000

The Politics of CANDU Exports

The Politics of CANDU Exports
by Duane Bratt, University of Toronto Press, 2006

The following is a chronology of Canada's nuclear science and technology.   Some international events are included in the following list because:

Local time is used.

Pre-1800 1800 1890
1900 1910 1920 1930 1940 1945 1950 1955
1960 1965 1970 1975 1980 1985 1990 1995
2000 2005
End Notes

Pre 1800:
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-5.1 billion:
A large star, several times the mass of our Sun and near the end of its series of fast nuclear fusion cycles, detonates as a supernova.   The shockwave from this cosmic blast compresses a nearby cloud of cold dust and gas, itself a product of earlier stellar explosions and enrichment in chemical elements, by way of stellar nucleosynthesis.   The compression wave triggers or accelerates gravitational collapse of the cloud into several dense, pre-stellar clouds; one becomes our Sun and its family of orbiting planets, moons, and other debris. {JF}
-5.0 billion:
Our protostellar Sun accretes sufficient material to reach a few tenths of the mass of the present Sun and the temperature and pressure at the center becomes sufficient to induce nuclear fusion.   The conditions are not yet hot enough to fuse ordinary hydrogen, but at one million kelvins, the protostellar Sun is sufficiently hot to burn deuterium, present as an impurity of about two out of every 100,000 hydrogen nuclei. {JF}
-4.8 billion:
Soon after the formation of the planets, the earth melts, due to radioactive heating, gravitational collapse and heavy meteorite bombardment.   The dense particles sink and the densest of them, including uranium, thorium and any remaining plutonium, collect at the very center of the earth.   When enough uranium collected, it is postulated a nuclear fission chain reaction began.   Located thousands of miles beneath our feet, the nuclear reactor, some 8 kilometres in diameter, may have been operating since almost the formation of the planet and could be the power source behind earth's magnetic field and thermal energy.   Periodic shutdowns due to fission product buildup would be responsible for frequent geological magnetic field reversals. {JF}
-1.8 billion:
Jun 17 Natural reactor at Oklo (Gabon) first goes critical at 10:37 (Gondwanaland Daylight Savings Time). Additional discussion here.

Oklo fossil reactor.  Gabon stamp.
~450 B.C.:
  Leucippus (Greece) proposed an atomic concept of matter. {A Chronology of the Atomic View of Nature}
~400 B.C.:
  Democritus of Abdera (Greece, c. 460-357 B.C.) taught: "The only existing things are the atoms and empty space; all else is mere opinion." {A Chronology of the Atomic View of Nature}
Sep 24  Martin Heinrich Klaproth (Dec 1 1743 - Jan 1 1817), a German chemist, presented his paper on the discovery of uranium to the Berlin Academy of Sciences.

Uranium Resources.  Issued 3 Sep 1980.

Klaproth identified zirconium as an element the same year.   Zirconium is a metal used extensively by the nuclear industry because of its low neutron absorption.
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Metallic zirconium first prepared by Jons J. Berzelius, a Swedish chemist
Abel Niepce de Saint Victor, a French photographer, exposed uranium compounds to sunlight and placed them, along with pieces of photographic paper, in a dark drawer.   He found that the uranium compounds exposed the photographic paper.   Niepce thought he had found some new sort of invisible radiation, and reported his findings to the French Academy of Science, but no one investigated the effect any further until Becquerel performed a similar experiment in March 1896.
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  Scottish physicist Wilson invented the cloud chamber for viewing vapour trails left by charged particles.
Nov 8 Wilhelm Conrad Roentgen discovered X-rays.

Wilhelm Conrad Roentgen (1845-1923), German Democratic Republic (East Germany) stamp issued 1965.
  Alexander Graham Bell experimented with X-rays in Baddeck, Nova Scotia.
Feb 7 First diagnostic radiograph (x-ray) in Canada taken by Professor John Cox, of the MacDonald Physics Laboratory at McGill University in Montreal.   The patient had been shot in the leg during a street brawl on Christmas Day, 1895, but doctors were unable to find the bullet by probing.   The radiograph was able to show the surgeons exactly where the bullet was embedded.
Mar 1 Henri Becquerel discovered radioactivity of uranium, because wrapped photographic plates became exposed by an unknown ray emanating from uranium salts.    He previously believed the salts had given off a type of x-ray due to exposure to sunlight, but discovered that the plates became exposed even on cloudy days.

Henri Becquerel (1788-1878), French stamp issued 1946.
Jul Marie and Pierre Curie extracted polonium from pitchblende.

Marie Sklodowska-Curie, Turkish stamp issued 1938.
Aug 1 New Zealand physicist Ernest Rutherford took up his appointment as the Macdonald Professor of Experimental Physics at McGill University, Montreal. See the Rutherford Museum at McGill.

Ernest Rutherford (1871-1937) Canadian stamp issued 24 Mar 1971.     London Midland Scottish Railway 'Lord Rutherford of Nelson', Jubilee class locomotive 45665, 1935 - 1962.  Click for details. Thanks to Simon Robinson.
Dec 26 Marie and Pierre Curie extracted radium from pitchblende.
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Apr Ernest Rutherford observed and named spontaneous radioactive disintegration - the unaided transmutation of elements - with Frederick Soddy of the McGill University Chemistry Department.   Soddy went on to win the Nobel Prize in Chemistry in 1921.

Frederick Soddy (1877-1956), Swedish stamp issued 1981.
  Ernest Rutherford discovered radium-224 with Frederick Soddy at McGill University.
  Alexander Graham Bell wrote a letter to his physician, Dr Z. T. Sowerby, suggesting placing radium sources in or near tumours:
The Crookes' tube from which Rontgen rays are emitted is, of course, too bulky to be inserted into the middle of a mass of cancer; but there is no reason why a tiny fragment of Radium sealed up in a fine glass tube should not be inserted into the very heart of the cancer, thus acting directly upon the diseased material.    Would it not be worth making experiments upon this line?
This technique is still employed to treat some cancers.

Alexander Graham Bell (1847-1922), American stamp issued 1940.
  At McGill University, Rutherford demonstrated that alpha particles are helium atoms and determined their decay series.   He coined the term "half-life" and prophetically stated, in his book "Radio-Activity":
There is reason to believe that an enormous store of latent energy is resident in the atoms of radioactive elements . . . If it were ever possible to control at will the rate of disintegration of the radioelements, an enormous amount of energy could be obtained from a small quantity of matter
Dec 10 Ernest Rutherford received the 1908 Nobel Prize in Chemistry "for his investigations into the disintegration of the elements, and the chemistry of radioactive substances". {} The prize was mainly based on his work performed when he was Professor of Experimental Physics at McGill, 1898-1907.
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Feb 1 Ernest Rutherford and Hans Geiger discovered the atomic nucleus.
  Frederick Soddy formulated the concept of isotopes.
June 6 Honorary Advisory Council on Scientific and Industrial Research established, later to become the National Research Council of Canada. {NRC/CNRC}
  Rutherford produced the first artificial transmutation of the atom.
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  Gilbert A. LaBine (1890 - 1977) discovered Canada's first uranium deposit at Great Bear Lake, Northwest Territories. LaBine was a partner in Eldorado Gold Mines.

Great Bear Lake, Northwest Territories.  Issued 16 Sep 1946
  Harold Clayton Urey, a chemist at Columbia University, discovered deuterium (heavy hydrogen) for which he won the Nobel Prize for Chemistry in 1934.
  Eldorado Gold Mines Ltd built a radium refinery at Port Hope, Ontario. Radium, a naturally-occuring intermediate product in the uranium decay chain, was used for cancer treatment.
Feb 17 Sir James Chadwick discovered the neutron.

Sir James Chadwick (1891-1974), Maldives stamp issued 1995.
Jan 11 Irene and Frederic Joliot-Curie created the first artificially-radioactive isotope (phosphorus-30).
Jun Fermi and co-workers describe neutron bombardment of uranium
Sep German chemist Ida Noddack suggested that elements in the middle of the periodic table were being formed as uranium broke up on the introduction of a neutron into its nucleus.   However, nobody had taken her suggestion seriously at the time as it was contrary to all conventional thinking, and she did not even try to verify her theory. (From Uranium's Scientific History 1789 - 1939, by Bertrand Goldschmidt, 1989)
Mar 19 First load of UO2 concentrates flown out of the Eldorado Gold Mines Ltd uranium mine at Port Radium, Northwest Territories. See The Eldorado Uranium Silver Express {CNS Bulletin Dec 2005}
Dec 19 Radiochemist Otto Hahn sent a letter, containing experimental results from irradiating uranium with slow neutrons, to nuclear physicist Lise Meitner. The minute amounts of barium in the irradiated uranium were fission products; Meitner and her nephew Otto Frisch developed theory of fission from these results.

1978 Austrian stamp featuring Lise Meitner    Otto Hahn (1879-1968), Angola stamp issued 2001.
Jan 6 The experimental results of irradiating uranium with slow neutrons were published in Naturewissenschaften (Nature) by Otto Hahn and Fritz Strassmann.
Feb 11 Meitner and Frisch publish theoretical interpretation of Hahn and Strassmann experiments, in two-page letter to Nature. First public description of fission process.
Mar 8 Frederic Joliot-Curie, Hans von Halban, Francis Perrin and Lew Kowarski sent a communication to Nature, entitled "Liberation of Neutrons in the Nuclear Explosion of Uranium" {Eggleston}.
Mar 15 Enrico Fermi and Leo Szilard showed that neutrons are produced in a fission reaction.

Fermi and a model of the carbon atom, Mar 26, 1948, at the University of Chicago's Institute for Nuclear Studies. Stamp issued Sept 29 2001, 100th anniversary of Fermi's birth in Rome.     On February 11, 1998, the 100th anniversary of his birth, Hungary issued a postage stamp honoring physicist Leo Szilard.
Apr 1 Irene and Frederic Joliot-Curie proposed fission reactor.
Aug 2 Physicist Albert Einstein signs letter to USA President Roosevelt, alerting him to possibility of atomic weapons and that Germany had begun weapons research.
Sep 1 Physicists Niels Bohr and John Wheeler publish comprehensive theory of nuclear fission.
Oct 18 Chalmers Jack Mackenzie of Saskatoon appointed acting head of National Research Council of Canada {Egglerston}.
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Mar George C. Laurence began experiments with a uranium-graphite sub-critical pile at the National Research Council of Canada, Ottawa. In the summers of 1941 and 1942 he was joined by Dr. B. Weldon Sargent, physics professor at Queen's University.
Apr MAUD committee set up in the UK, under chairmanship of Prof. G.P. Thompson, to discuss possibility of atomic weapon {Eggleston}.
Jun Hans von Halban, Lew Kowarski and other refugee European scientists join UK nuclear team {Eggleston}.
Jun 15 Philip Abelson and Edwin McMillan demonstrate, with Berkeley cyclotron, that neutrons captured by U-238 lead to the creation of elements 93 (later named neptunium) and 94 (later named plutonium).
Aug Sir Henry Tizard leads British scientific mission to U.S.A. and Canada, results in co-operation of Canadian science and technology and scientific Lend-Lease assistance from the U.S.A.
Nov 8 First U.S.A. contract for uranium-graphite reactor research awarded to Columbia University {Eggleston}.
Jan 28 H. Grenville Smith, V.P. of Canadian Industries Limited (CIL), offered $5,000 to assist G.C. Laurence's work in Ottawa, thanks to Dr. John Cockroft, who had visited Ottawa in the summer of 1940 with the U.K. Tizard scientific mission.
Jan 28 Glenn T. Seaborg and Edwin M. McMillan co-discovered plutonium at the Berkeley Campus of the University of California.
Mar 28 Plutonium confirmed to be fissile.
Apr 9 UK MAUD committee decides that Britain might be able to produce a nuclear weapon, with Canada's and Commonwealth help {Eggleston}.
  G.C. Laurence and B.W. Sargent write "Uranium Fission in a Bulk of Carbon and Uranium Oxide" describing their sub-critical experiments {Eggleston}.
Aug 17 "OK, let's go." - C.D. Howe, Minister of Munitions and Supply in the wartime cabinet, agreed to set up the Montréal laboratory (forerunner of the Chalk River Laboratory). See also CNS Québec branch
Aug 17 Proposal that Cavendish Laboratory (Cambridge, UK) heavy-water team be moved to Canada. First proposal that a D2O program start in Canada.
Sep 1 American Manhattan Project (development of the a-bomb) began.
Nov 5 Construction begins on uranium isotope separation plant at Oak Ridge, Tennessee.
Dec 2 Enrico Fermi's Chicago Pile 1 (CP-1) reactor attained first criticality at 15:25. This was the world's first human-made reactor. Later rebuilt as CP-2 at the Argonne National Laboratories in Illinois.
Dec 12 Dr. C.J. Mackenzie formally requests from the U.S.A authorities: three tons of uranium oxide, five tons of uranium metal, half a ton of uranyl nitrate, 60 tons of graphite and six tons of heavy water. {Eggleston}
Feb Dr. James Conant, a senior U.S.A. scientific administrator, wrote a letter to C.J. Mackenzie that laid down the terms of American co-operation with the Montreal Laboratory. Severe restrictions on co-operation were now in place from the Americans, a sharp change in policy. This change was likely due to the increased army control of the U.S.A. program {Eggleston}.
Feb First report issued by the Montreal Laboratory. See King's College London, Liddell Hart Centre for Military Archives, Nuclear History Database.
Mar 20 Reactor CP-2 first went critical. CP-2 was reactor CP-1 (see Dec 2, 1942) rebuilt at the Argonne National Laboratories.
Jun 1 Cominco produced Canada's first heavy water (D2O) in Trail, B.C.
Nov 4 Test reactor X-10 first critical, at Oak Ridge National Laboratories, Tennessee.
Apr 13 Combined Policy Committee (for implementing a British-American collaboration agreement on nuclear research) approves construction of a Canadian heavy water moderated reactor, later known as NRX.
Apr 26 John Cockroft arrives at the Montréal laboratory to take over directorship from Hans Halban. Later Cockroft became the first director of the Chalk River Nuclear Laboratories.
May 15 CP-3 (Chicago Pile 3, Argonne National Laboratories, Illinois), the world's first D2O moderated reactor, attained first criticality. Photo of CP-3 on 15 May 1944
Jul 7 Defence Industries Limited (DIL) was selected as the engineer and construction manager, and Fraser Brace was selected as the contractor, to build a 10 MWth reactor (NRX, later increased to 40 MWth) at the new Canadian nuclear laboratories. {JLG}
Jul 12 Chalk River made first choice as site of Canadian nuclear laboratories.
Jul 17 Defence Industries Limited (DIL) accepts contract to build the Canadian nuclear laboratories {RB}
Jul 25 Cockroft suggested building a pilot reactor for the large NRX reactor. This became the ZEEP project built at Chalk River {RB}
Aug 18 Chalk River site officially chosen for the new National Research Council of Canada (later transferred to AECL) nuclear laboratory.
Aug 23 Fraser Brace Limited Limited subcontracted by DIL to build the Canadian nuclear laboratories {RB}
Aug 24 Decision made to build the ZEEP heavy-water reactor.
Sep 26 Hanford "B" Pu production reactor first critical.
Oct 10 ZEEP construction approval.
Dec 17 Hanford "D" Pu production reactor first critical
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Feb 25 Hanford "F" Pu production reactor first critical.
Jul 16 Trinity test, the first atomic bomb, detonated in the USA.
Aug 6 Hiroshima (Japan) bombed with uranium-235 atom bomb.
Aug 9 Nagasaki (Japan) bombed with plutonium-239 atom bomb.
Aug 13 Canada's atomic energy program first made public. Canadian Department of Reconstruction Press Release
Sep 4 ZEEP reactor completed.
Sep 5 ZEEP reactor attained first criticality at 15:45. The first reactor criticality outside the USA.
Aug 31 Atomic Energy Control Act passed in Canada.   This was the start of the Atomic Energy Control Board.
Sep W.B. Lewis arrives from the U.K. to become director of the National Research Council of Canada's Atomic Energy Division.
Sep 30 John Cockroft left Chalk River laboratories for the UK, to direct the Harwell laboratories.
Apr 21 ZEEP shut down for transfer of heavy water to start NRX at Chalk River Nuclear Laboratories. {Eggleston}
Jul 22 The 20 MWth National Research Experimental reactor (NRX) at Chalk River Nuclear Laboratories attained first criticality at 06:13. It was later uprated to 30 MWth, and eventually to 42 MWth.
Sep NRX attained 250 kW(th) for first time.
Sep Eldorado received exclusive rights to market Co-60 from NRC's Chalk River laboratories.
Oct 31 First isotope shipment from NRX. Cerium-144 to the University of Saskatchewan (Saskatoon).
Mar NRX attained 2 MW(th) for first time.
May NRX attained 12 MW(th) for first time.
Sep NRX attained 20 MW(th) for first time.
Mar 29 First patient treated with the 24 MeV betatron at the University of Saskatchewan.
Jul 15 Cobalt-60 cancer therapy first proposed.
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Mar 31 ZEEP went critical for first time since it was shut down in 1947, to supply heavy water for NRX. ZEEP was used in the NRU design process. {Eggleston}
Dec 13 Stephen Whelan, a process operator at Chalk River Nuclear Laboratories, died in a chemical explosion. {Eggleston}
  In the Joule Memorial Lecture of 1951, Sir John Cockcroft said of UK reactor development: "we do not expect to produce a cheaper source of power than that derived from coal - it is likely, in fact, to be somewhat more expensive.   What we are aiming at is to increase the total power available".    He concluded by saying: "The essential thing is now to get on and build some power reactors".   Cockroft was the first director of Canada's Chalk River nuclear laboratories 1944 - 1946.
Jul 15 Dr. John Robson published his verification of the radioactive nature of the neutron, along with the first accurate measurement of its half-life (12.8 +/- 2.5 minutes), using the NRX reactor at the NRC's Atomic Energy Project at Chalk River, Ontario. {Phys. Rev. 83, 349-358, 1951}
Aug 17 Beam therapy unit (cobalt-60 cancer treatment) designed by Harold Johns, installed at university of Saskatchewan. This unit eventually retired in 1972, having treated 6,728 patients {I&I}.
Aug 27 W.B. Lewis declared nuclear power to be economical.
Oct 27 First cancer patient treated with Co-60 in London, Ontario, using an Eldorado Mining & Refining Commercial Products Division (CPD) beam therapy unit (Eldorado A) {I&I}.
Cobalt Therapy, 1951.  Issued 17 Jun 1988
Nov 8 First cancer patient treated with Co-60 in Saskatoon, Saskatchewan, with Harold Johns' beam therapy unit. {I&I}
Dec 20 Experimental Breeder Reactor-1 (EBR-1), at the National Reactor Testing Station in Idaho, USA, generated first usable amount of electricity (800 W) from nuclear energy.   This was sufficient to power a string of four 200-W light bulbs.   The following day the reactor generated 100 kWe.   This electricity generation was only a demonstration, showing that it could be done with a reactor. See Nuclear News, Nov 2001, published by the American Nuclear Society for more information.
Feb 14 Atomic Energy of Canada Limited (AECL) was incorporated as a federal crown corporation, under Part 1 of the Companies Act 1934.
Apr 1 The Chalk River nuclear establishment of the National Research Council of Canada was transferred to Atomic Energy of Canada Limited (AECL).
Aug 1 AECL absorbed the Commercial Products Division of Eldorado Mining & Refining, which developed and marketed Cobalt-60 cancer therapy equipment and other radioisotope applications.
Oct 31 First hydrogen bomb (USA) tested.
Dec AECL's CPD bought land in Ottawa (Tunney's Pasture) for a new headquarters and handling/processing facility. This was to cope with the demand for the Theratron Co-60 cancer treatment units and the inadequate rented lab and machine shop space in Ottawa. {I&I}
Dec 12 NRX accident at 15:07, leading to some fuel melting and fission product releases.
Mar 30 World's first pressurized water reactor (PWR) attained first criticality in the USA.   The reactor was designed for the USS Nautilus submarine.
May First Theratron B Co-60 unit from AECL's CPD, installed in Francis Delafield Hospital in New York. {I&I}
May 22 Removal of the damaged calandria of NRX, in preparation for rebuilding. {Canada Enters the Nuclear Age}
Dec 8 USA President Dwight Eisenhower delivered "Atoms for Peace" address, calling for the establishment of the International Atomic Energy Agency to devise "methods whereby this fissionable material would be allocated to serve the peaceful pursuits of mankind. Experts would be mobilized to apply atomic energy to the needs of agriculture, medicine and other peaceful activities. A special purpose would be to provide abundant electrical energy in the power-starved areas of the world."
  Government approval for the first Canadian power reactor - NPD.
Feb 16 Second start-up (at 10:30) of NRX following rebuilding.
Apr 1 Atomic Energy Control Board Act amended to transfer research and production functions of the AECB to a minister (the chairman of the Privy Council Committee for Scientific and Industrial Research) {JLG}
Jun 26 First nuclear-generated electricity in USSR. First nuclear power reactor in the world connected to an electrical grid, at 17:30. The 5 MWe NPP (also known as the APS-1) reactor at the Institute of Physics and Power Engineering in Obninsk (~110 km southwest of Moscow) officially closed Apr 30 2002. {IAEA}
Aug Studies indicated that the design, engineering, and construction of a prototype power reactor should be undertaken in Canada - size 10 - 20 MWe - with D2O moderator and coolant using natural uranium fuel. {JLG}
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Jan First staff move to new headquarters of AECL's CPD at Tunney's Pasture in Ottawa. {I&I}
Jan 17 First sailing of a nuclear powered ship - the USS Nautilus. AECL's Chalk River Nuclear Laboratories had been involved in testing the fuel (UO2) for the US reactors, and the CPD provided the radium-beryllium neutron sources required to start the reactors. {I&I}
Mar 8 Dr. W.B. Lewis, VP for research and development of AECL, forecast that atomic power plants would be producing electricity economically in Canada between 1960 and 1965.
Mar 10 AECL Board reviewed the proposals for a power reactor and recommended that the Canadian General Electric Company Limited be selected to design and construct the demonstration nuclear electric power plant (NPD), and that the Ontario Hydro proposal for participation be accepted. Contract signed with CGE in Mar. {JLG}
Apr 7 Dr. David Keys, Scientific Adviser to the President of AECL, said in a speech to the Empire Club: "It is expected that power from nuclear energy can be generated at a cost competitive with that from coal but such factual knowledge can only be gained by actual experience."
  AECL's CPD develops Theratron Jr., the first of 140 such machines sold worldwide. {I&I}
Sep 19 Sod turning ceremony at the Des Joachims site on the Ottawa River, in preparation for the first Canadian power reactor - NPD.
Oct 17 Calder Hall (Unit 1) in the UK was officially opened by Her Majesty the Queen.    This reactor was the first of four 60 MWe Magnox type reactors connected together, and continues to operate today.  Anthony Eden, Prime Minister of the United Kingdom, wrote the following for the occasion:
Of all the events which have taken place in this year 1956, history may remember longest the day when Calder Hall began to feed electricity into the national grid network.   For the first time anywhere in the world nuclear energy will be used to supply electricity on a large scale.   This will be a memorable day in man's forward march.   It will be the outcome of ten years of sustained work by British scientists and engineers.

In 1946 we started our development programme with few resources except the knowledge stored in the brains of a handful of scientists.   Their faith and their perseverance have opened up the prospect of a new industrial era.   That new era will be rich in opportunities for those countries which have the skill and expertise to seize them.   Calder Hall shows that we have both.   We have made a splendid start and I am confident that we will not fall behind in the race in which we are engaged.
  The confirmed uranium ore reserves at Elliot Lake, Ontario, were greater than the total of all 600 plus uranium mines in the USA (from Ellicott International).
Mar 27 AECL, Ontario Hydro and Canadian General Electric replace NPD-1 power reactor design in favour of a horizontal pressure-tube design (NPD-2).   This was the start of the CANDU design.
May The Nuclear Power Group (Ontario Hydro, other utilities, manufacturers and AECL) recommended that a nuclear power reactor of about 200 MWe be considered, employing pressure tubes to contain the fuel and heavy water coolant. {JLG}
Jul 29 United Nations' International Atomic Energy Agency founded.
Oct CPD displays prototype Gammacell Co-60 irradiator at the Atom Fair in New York. {I&I}
Oct 10 Windscale-1 (UK) reactor fire.
Nov 3 The 135 MW National Research Universal (NRU) at Chalk River Nuclear Laboratories attains first criticality at 06:10.
Nov 29 The 100 Wth Pool Test Reactor (PTR) at Chalk River Nuclear Laboratories attains first criticality at 12:05 pm.   The reactor was designed and built by Canadair, now a division of Bombardier, builders of the CL-215 water bomber, the Challenger executive and Regional jets, and the Acela high speed trains, and the Ski-doo. {JTR}
Dec 23 Shippingport (near Pittsburgh, Pennsylvania, USA) PWR attained first full power. This is the first American civilian power reactor.
May 7 J.L. Gray appointed President of AECL.
May 23 NRU reached full power of 200 MW (th) for first time.
May 24 NRU had a fuel rod failure, which broke upon removal and fell to the floor.    The fuel rod caught fire and spread contamination.
Jun NPD construction began, following design change.
Aug 15 NRU restarted after May 24 fuel rod fire.
Oct 5 Vinca (Yugoslavia) heavy-water research reactor had a criticality excursion.    One person died.
  CPD delivers first production Gammacell Co-60 irradiator. {I&I}
Apr 4 McMaster University (Hamilton) reactor first criticality at 00:36 (12:36 am).
Apr 10 McMaster University reactor officially opened.
Jul Government approval for Douglas Point 220 MWe reactor (to be called CANDU, which eventually became the general name for AECL-designed pressurized heavy water reactors).
Jul 21 NS Savannah (USA merchant ship) launched.   This was the world's first nuclear-powered civilian vessel.
Sep Official annoncement of the construction of the Douglas Point reactor.
Oct 1 Decision made to build the Whiteshell Nuclear Research Establishment of AECL, 100 km east northeast of Winnipeg, Manitoba.
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Feb 1 Construction (site clearing) started at Douglas Point.   This was the first medium-sized CANDU (220 MWe) and the second Canadian pressurized heavy water reactor prototype, after NPD.
Jul 10 40 MWth Canadian-built CIRUS research reactor (India) attained first criticality.
Aug 28 The letters patent were signed, bringing the Canadian Nuclear Association into existence.
Sep 7 200 Wth ZED-2 at at Chalk River Nuclear Laboratories attained first criticality.
Nov Federal Food and Drug Directorate approved irradiation of potatoes for human consumption. {I&I}
Jan 3 SL-1 accident at 21:01 at the National Reactor Testing Station, Idaho Falls, USA.   Three people died.
Jun 19 The final shipment of heavy equipment left the Canadian General Electric plant in Peterborough for arrival at NPD after a 2.5 day journey from .   The shipment consisted of the calandria vessel and two refuelling machine carriages.   The calandria, 17 ft in diameter, 15 ft long and 35 tons, covered the 235 miles at an average of 9 mph.   North Renfrew Times
Jun 24 NPD calandria vessel installed in reactor vault.
Aug 21 World's first atomic-powered weather station installed on Axel Heiberg Island (Northwest Territories of Canada), 1100 km from the North Pole.   The unmanned 5 watt station was powered by Sr-90 which heated 60 pairs of lead telluride thermoelements.   The weather station required the electricity (stored in batteries) to run instrumentation and send out a transmission every 3 hours.   The weather station successfully completed its 2 year test, and was removed in Jul 1965. {"Power from Radioisotopes", US Atomic Energy Commission, Dec 1966 Revision}.   More information here.
Fall AECL's CPD mobile irradiator processed ~800,000 lbs of potatoes for human consumption, in field trials in Ontario and the Maritimes. {I&I}
Apr 11 NPD attained first criticality 02:40.
May "Canadian nuclear power reactors have developed away from any primordial weapons program and from the outset had been designed to reach economic competition with conventional coal costing 30 cents per million BTU or less ... the special merit of nuclear power in Canada will be the low fuel cost of 1 mill per kWh [of electricity] or less".
        - W.B. Lewis to the Northwest Public Power Association in Victoria B.C.   [Nuclear Canada Yearbook 1985]

Note:  One million BTU of coal (heat) will produce about 120 kWh of electricity assuming a 40% thermal efficiency (thus the fuel alone cost ~2.5 mill per kWhe in 1962).  According to the Bank of Canada inflation calculator, 1 mill ($CDN 0.001) in 1962 is equivalent to 6.2 mill in 2001.
May 8 NPD generated first nuclear-generated steam in Canada.
May 12 First steam to NPD turbine.
Jun First operation of an orbiting radioisotope thermal generator (in a US satellite), powered by Pu-238. [Nuclear Canada Yearbook 1985]
Jun 4 NPD delivered first nuclear-generated electricity to a Canadian electrical grid at 13:31.
Jun 6 NPD reached 25% full power for first time.
Jun 17 NPD reached 50% full power for first time.
Jun 28 NPD attained full power (20 MWe net) for the first time at 08:49.
Sep 25 NPD declared in service, with an opening ceremony including the Hon. Leslie Frost (Ontario Premier, 1949-1961), J. Herbert Smith (President, Canadian General Electric), W.B. Lewis (AECL Vice President), the Hon. Gordon Churchill (federal Minister of Trade and Commerce, 1957-1960), J. Lorne Gray (AECL President), the Hon. John P. Robarts (Ontario Premier, 1961-1970) and Ian F. McRae (Canadian Nuclear Assn President). [Nuclear Canada Yearbook 1985]
Oct $14.5 million contract awarded to Canadian General Electric, to build the WR-1 reactor at the Whiteshell Nuclear Research Establishment of AECL (now Whiteshell Laboratories). [Nuclear Canada Yearbook 1985]
Fall Completion of conversion of AECL's National Research Experimental (NRX) reactor from natural uranium to high-enriched fuel. {Canada Enters the Nuclear Age}
Dec 3 First attempt to refuel NPD at full power.   Attempt failed, due to a leak in the seal between the fuelling machine and the fuel channel end fitting.   Dousing system triggered and suppressed containment pressure rise.   No significant activity released, and the reactor was re-started 12 days later.
Oct 15 CIRUS (India) research reactor attained first full power.
Nov 24 First successful refuelling of NPD at full power.   This made NPD the first pressurized water power reactor in the world to be refuelled on-line.
Dec Two agreements reached between Canada and India for a 200 MW CANDU in Rajasthan state.   "The safeguards issues that stalled agreement were settled by permitting reciprocal inspection at will of all products from the Rajasthan and Douglas Point Reactors." {Nuclear Canada Yearbook 1985}
Mar Pakistan's Economic Planning Commission approved recommendation of the country's Atomic Energy Commission that a 132 MWe heavy water natural uranium fuelled plant be built in the Karachi area.   Financing is expected to include funds under the Colombo Plan and credit provided by the Exports Credits Insurance Corporation.   Canadian General Electric awaited financing agreement before making a firm bid. {Nuclear Canada Yearbook 1985}
Mar Completion of conversion of AECL's National Research Universal (NRU) reactor from natural uranium to high-enriched fuel. {Canada Enters the Nuclear Age}
Apr First approval of an irradiated food product for public use - canned bacon (used by the US army for some time previously). {Nuclear Canada Yearbook 1985} See also Nov 1960, however.
May 24 Pakistan government signed contract with Canadian General Electric for construction of Karachi Nuclear Power Plant (KANUPP).
Jun Canadian Nuclear Association forecast a total installed capacity of 14 000 MWe in Canada by 1985. [Nuclear Canada Yearbook 1985]   By 1985, 11 129 MWe was operational; by 1990 13 872 MWe was operational, and by 1993 16 699 MWe (gross) was operational.
Aug 20 Plans announced for the construction of the first two large-scale CANDU reactors, to be built in Pickering Township, near Toronto.   Eventually eight reactors built there.
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Mar 19 First WR-1 systems taken over from construction for commissioning.
Jun 1 WR-1 construction completed.
Aug 16 AECL's Commercial Products Division began construction of its new facilities in Kanata, just west of Ottawa. CPD was the first company to move to the new city. {I&I}
Sep The start-up of the world's first commercial food irradiation facility, designed and built by AECL, located at Mont St-Hillaire, Quebec. {AECL}
Sep Ontario premier John Robarts, the Hon. C.M. Drury (Federal Minister of Industry), and Pickering Township Reeve C.W. Laycox officially launch construction of Ontario Hydro's "1,080,000 kWe Pickering Nuclear Station" (Pickering eventually reached 4,320,000 kWe).
Oct 31 WR-1 pre-critical commissioning completed.
Nov 1 WR-1 attained first criticality at 20:04. See log book entry (943 kB pdf)
Dec Dr. A.J.Mooradian appointed Managing Director of the Whiteshell Nuclear Research Establishment of AECL.
Dec 4 WR-1 high power commissioning started.
Dec 16 WR-1 reached 100% power for the first time.
Jan 12 Whiteshell Reactor No. 1 (WR-1) in full operation.
May CGE selected as one of three bidders for a 300 MWe reactor in Finland.   Plans for this reactor ended in 1967.
Jun 1 Pickering-1 construction start.
Jul Construction of Karachi Nuclear Power Plant (KANUPP) in Pakistan began.
Sep 1 Gentilly-1 construction start.
Sep 1 Pickering-2 construction start.
Nov 15 Douglas Point attained first criticality at 16:26.
Peaceful Uses, Atomic Energy.  Featuring Douglas Point.  Issued 27 Jul 1966
Dec W.B. Lewis awarded the first Outstanding Achievement Award of the Public Service of Canada, for his contribution to Canada's nuclear program.
Dec 16 Agreement signed to build 200 MWe CANDU Rajasthan-2 (aka RAPS-2, India).
Jan 7 Douglas Point generated its first electricity.
Apr Control rod in Douglas Point contacted calandria tube in channel K-6, and vibrations wore a hole in the CT. Tube replaced. {AECL Review Oct 1968}
Apr AECB grants Ontario Hydro permission to construct a further two 500 MWe reactors at Pickering.
Dec Gentilly-1 4-foot thick concrete wall poured with a slip form in 17 days and only "two hours behind schedule".
Dec 1 Pickering-3 construction start.
May 1 Pickering-4 construction start.
Jul 1 Canada, the United States, Britain, the Soviet Union and 58 other nations signed the Nuclear Nonproliferation Treaty.
Sep 26 Douglas Point declared in service.
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  AECL's Commercial Products Division closed its radium business, which had been the foundation of the CPD under Eldorado Mining and Refining. Radium sales had diminished due to newer isotopes superceding radium. Remaining radium stocks were donated to China. {I&I}
Mar 1 First on-power refuelling of Douglas Point, at 135 MWe (61% full power) {AECL Review Ap 1970}.
May 1 NRU production of molybdenum-99 began.
Jul 27 ZEEP shut down and retired.
August 13 NRX shut for calandria vessel change {AECL Review Jan 1971}.
Oct 19 Radioisotope-powered Minor Atomic Prolonged Life Equipment (MAPLE) navigation light (5 W electrical) installed at Brockville, Ontario. It was designed and built by AECL (Commercial Products Division), and remained in operation for three years. {The Lighthouse Digest, October 2004}
Nov 12 Gentilly-1 attained first criticality at 22:50.
Dec 1 Bruce-2 construction started.
Dec 21 NRX re-started after calandria vessel change {AECL Review Jan 1971}.
Jan Pickering-1 fuel loaded. The late Roger Barrand loaded the first fuel. He's also shown here
Feb 25 Pickering-1 attained first criticality at 00:30.
Mar 16 Pickering-1 generated first steam.
Apr 4 Pickering-1 generated first electricity.
Apr 5 Gentilly-1 first grid connection.
May 1 NRX production of molybdenum-99 began.
May 1 20 kWth SLOWPOKE at AECL Tunney's Pasture (Ottawa) attained first criticality.
May 30 Pickering-1 attained full power for the first time.
Jun 1 Bruce-1 construction started.
Jun 4 University of Toronto received AECB licence to run its 20 kWth SLOWPOKE-1 research reactor.  First criticality at 14:47, Jun 5 1971.
Jul 29 Pickering-1 declared in service.
Aug 1 KANUPP (Pakistan) attained first criticality.
Sep 15 Pickering-2 attained first criticality.
Sep 29 Pickering-2 generated first steam.
Oct 18 KANUPP (Pakistan) generated first electricity.
Oct 6 Pickering-2 generated first electricity.
Nov 7 Pickering-2 attained full power for the first time.
Dec 30 Pickering-2 declared in service.
Feb 25 Pickering station officially opened by Ontario Premier Bill Davis.
Apr 24 Pickering-3 attained first criticality.
Apr 29 Pickering-3 generated first steam.
May 3 Pickering-3 generated first electricity.
May 12 Pickering-3 attained full power for the first time.
May 13 Gentilly-1 attained full power for the first time.
Jun 1 Pickering-3 declared in service.
Jun 5 NRU shut down for refurbishment. {JW}
Jul 1 Bruce-3 construction started.
Aug 11 RAPS-1 (India) attained first criticality.
Sep 1 Bruce-4 construction started.
Oct 4 KANUPP (Pakistan) reached full power for the first time.
Nov 28 KANUPP declared in service.
Feb Gentilly-2 contract signed
Apr AECL heavy water plant (A plant) at Douglas Point starts operation.   Ontario Hydro buys it in Jul.
May 16 Pickering-4 attained first criticality.
May 19 Pickering-4 first steam to turbine.
May 21 Pickering-4 first first electricity.
May 28 Pickering-4 first full power at 21:31.
Jun 17 Pickering-4 declared in service. This made Pickering the world's largest power reactor site (2168 MWe gross) until superceded by Fukushima,Japan in 1978.
Jun 22 W.B. Lewis retired from AECL.
Dec 16 RAPS-1 (India) declared in service.
Dec 20 Contract for Embalse (Argentina) signed with AECL.
Apr Point Lepreau contract signed
May 18 India detonated Pokhran-I (aka "Smiling Budha") atomic "device", claiming it was a peaceful explosion.
Jun Gentilly-2 first containment concrete
Aug 2 NRU returned to service after major refurbishment, including reactor vessel change. {JW}
Oct 18 Point Lepreau (New Brunswick) reactor site approved by AECB.
Nov 1 Pickering-5 construction started.
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  Montreal Neurological Institute developed and installed Canada's first positron emission tomography (PET) scanner
Jan 27 Wolsong-1 (South Korea) contract signed
Mar 22 Browns Ferry (USA) fire.   No radioactive releases, but safety implications require other reactors to upgrade fire protection.
May 2 Point Lepreau construction license approved by AECB.
Jul Point Lepreau first containment concrete
Oct 1 Pickering-6 construction started.
Oct 31 First containment concrete at Embalse (Argentina).
Jan 26 Wolsong-1 (South Korea) contract effective
Mar 1 Pickering-7 construction started.
Mar 1 SLOWPOKE-2 (rebuilt from SLOWPOKE-1) at the University of Toronto attained criticality.
May 1 SLOWPOKE at L'Ecole Polytechnique (Montréal) attained first criticality.
Jul 1 20 kWth SLOWPOKE at Dalhousie University (Halifax) attained first criticality.
Jul 27 Bruce-2 attained first criticality.
Sep 1 Pickering-8 construction started.
Sep 4 Bruce-2 generated first electricity.
Dec 17 Bruce-1 attained first criticality.
Jan 14 Bruce-1 generated its first electricity.
Mar AECB limits Douglas Point to 70% thermal power, restored to 100% Nov 19, 1981 {Cdn Energy News Vol 1 #41}
Apr 1 University of Alberta 20 kWth SLOWPOKE-2 attained first criticality.
Jun 1 Gentilly-1 shut down permanently.
July Ontario government commits to build 4-reactor Darlington nuclear station (near Bowmanville, Ontario).
Sep 1 Bruce-1 declared in service.
Sep 1 Bruce-2 declared in service.
Nov 28 Bruce-3 attained first criticality.
Dec 12 Bruce-3 generated first electricity.
Jan 1 Bruce-6 construction started.
Jan 24 COSMOS-954 (USSR satellite with nuclear reactor) crashes in the North West Territories.
Feb 4 Bruce-3 declared in service. {BP}
Feb 8 Wolsong-1 (South Korea) first containment concrete
Jun 1 Bruce-5 construction started.
Dec 10 Bruce-4 attained first criticality.
Dec 21 Bruce-4 generated first electricity.
Jan 18 Bruce-4 declared in-service. {BP}
Mar 28 Three Mile Island Unit 2 reactor accident (USA) began at 04:00.
Apr 1 Decision made to decommission Gentilly-1.
May 1 Bruce-7 construction started.
May 11 Cernavoda-1 (Romania) contract signed
Aug 1 Bruce-8 construction started.
Sep 11 First meeting of the Council of the Canadian Nuclear Society.
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Oct Cernavoda-1 (Romania) first containment concrete
Oct 8 RAPS-2 (India) attained first criticality (NPCIL)
Nov 1 RAPS-2 (India) first synchronized to grid (NPCIL)
Apr 1 RAPS-2 (India) declared in-service (NPCIL)
May 1 20 kWth SLOWPOKE at Saskatchewan Research Council (Saskatoon) attains first criticality.
Jul 19 NPD reactor suffers flood in lower boiler room, due to failed expansion joint on dousing tank. Reactor shut and cooled, and restarted in Aug after repairs. {CNS}
Sep 1 Darlington-2 construction started.
Nov 19 AECB allows Douglas Point to operate at 100% thermal power, following modifications and revised analysis of emergency core cooling system. Reactor had been limited to 70% thermal power since Mar 1977 {Cdn Energy News Vol 1 #41}
Feb 9 Bruce 2 shut due to leaking pressure tube rolled joint.
Mar 16 Bruce 2 restarted after pressure tube replaced.
Apr 1 Darlington-1 construction started.
Apr 1 Point Lepreau fuel loaded.
Apr 4 Gentilly-2 fuel loaded.
Jun 16 First concrete pour at Cernavoda-2 (Romania) {AECL}.
Jul 21 Point Lepreau operating license approved by AECB. First CANDU 6 to be licenced in the world.
Jul 25 Point Lepreau attained first criticality at 20:02 {CNS}. First CANDU 6 to attain criticality.
Aug 15 to 21 Wolsong-1 fuel loaded.
Sep Bruce 3 attained world record for continuous power reactor operation, of 494 days.
Sep 11 Gentilly-2 attained first criticality.
Sep 11 Point Lepreau first synchronized with the grid.
Oct 16 Point Lepreau reaches 25% full power for the first time.
Oct 23 Pickering-5 attained first criticality.
Nov 21 Point Lepreau reaches 50% full power for the first time.
Nov 21 Wolsong-1 (Korea) attained first criticality.
Dec 4 Gentilly-2 first grid synchronization.
Dec 18 Pickering-5 generated first electricity.
Dec 18 Point Lepreau attained full power for the first time.
Dec 20 Embalse (Argentina) fuel loaded.
Dec 31 Wolsong-1 (Korea) first grid synchronization.
Jan 2 Gentilly-2 attained 50% power for first time.
Feb 1 Point Lepreau declared in-service, and began exporting electricity to the USA. First CANDU 6 to be declared commercial.
Mar 13 Embalse (Argentina) attained first criticality.
Mar 24 Pickering-5 attained full power for the first time.
Mar 26 Wolsong-1 (South Korea) attained full power for the first time.
Mar 28 Point Lepreau first on-power refuelling.
Mar 31 Gentilly-2 attained first full power.
Apr 22 Wolsong-1 (Korea) declared in service.
Apr 25 Embalse (Argentina) first synchronized with the grid.
May 10 Pickering-5 declared in service.
Jul 2 MAPS-1 (India) attained first criticality.
Jul 12 Wolsong-1 (Korea) first on-power refuelling.
Aug 1 11:10 Pickering-2 pressure-tube G16 rupture.   No safety systems were required for shutting the reactor.   The reactor was shut for retubing with Zr-2.5Nb pressure tubes.
Aug 11 Pickering-5 first refuelling.
Sep 15 Embalse (Argentina) attained first full power.
Sep 17 Embalse (Argentina) first on-power refuelling.
Oct 1 Gentilly-2 declared in service.
Oct 15 Pickering-6 attained first criticality.
Nov 8 Pickering-6 generated first electricity.
Nov 14 Pickering-1 shut for retubing.
Nov 21 Gentilly-2 first refuelling.
Jan 1 20 kWth SLOWPOKE at AECL Tunney's Pasture (Ottawa) shut down.
Jan 20 Embalse (Argentina) declared in-service.
Jan 27 MAPS-1 (India) declared in service.
Feb 1 Pickering-6 declared in service.
May 4 Douglas Point shut down permanently.
May 29 Bruce-6 attained first criticality.
Jun 1 20 kWth SLOWPOKE at AECL Kanata attained first criticality.
Jun 26 Bruce-6 generated first electricity.
Jul 23 Bruce-6 first full power.
Sep 1 Darlington-3 construction started.
Sep 14 Bruce-6 declared in service.
Oct 22 Pickering-7 attained first criticality.
Nov 15 Bruce-5 attained first criticality.
Nov 17 Pickering-7 generated first electricity.
Dec 2 Bruce-5 generated first electricity.
Dec 7 Bruce-5 attained first full power.
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Jan 1 Pickering-7 declared in-service.
Mar 1 Bruce-5 declared in-service.
May 17 WR-1 shut down for the final time.   From the final display screen {Bun Baxter}:
On 85/05/17 at 14:40:13 - Reactor tripped, D/L scanning
On 85/05/17 at 14:41:12 - Reactor shut down, D/L scanning
Jul 1 Darlington-4 construction started.
Aug 12 MAPS-2 (India) attained first criticality.
Sep 1 SLOWPOKE-2 at the Royal Military College, Kingston, attained first criticality.
Dec 17 Pickering-8 attained first criticality.
Jan 7 Bruce-7 first criticality.
Jan 21 Pickering-8 generated its first electricity.
Feb 22 Bruce-7 produced first electricity.
Feb 28 Pickering-8 declared in service.
Mar 1 SLOWPOKE-2 at University of West Indies (Jamaica) first critical.
Mar 21 MAPS-2 (India) declared in service.
Mar 28 Bruce-2 cold fuel channel failure.
Apr 10 Bruce-7 declared in service.
Apr 26 Chornobyl-4 (Ukraine) had a major accident at 01:23.   Reactor destroyed, 31 acute deaths.
Jan 10 W.B. Lewis died.
Feb 15 Bruce-8 first criticality.
Mar 9 Bruce-8 first produced electricity.
Mar 25 Tokamak de Varennes created first plasma.
May 5 NPD shut down for semi-annual maintenance and inspection; a pressure-tube inspection revealed the need for retubing.
May 22 Bruce-8 declared in service.
May 29 Canadian Irradiation Centre opened in Laval, Québec. {I&I}
Jul 1 2 MWth SLOWPOKE Demonstration Reactor (SDR) at Whiteshell Laboratories attained first criticality.
Jul 24 Decision made to shut NPD permanently.   The station output was only 22 MWe, it had fulfilled its role as a demonstration reactor, and now needed retubing.
Sep 4 Pickering-1 first synchronization to grid at 00:21 following retubing. {COG}
Sep 4 Pickering-1 first100 % power following retubing. {COG}
Oct 1 Pickering-1 declared in service after retubing.
Mar 14 Ontario Hydro board approves retubing of Pickering 3 and 4.
Oct 7 Pickering-2 synchronized with grid at 15:30, following retubing.
Nov 11 Pickering-2 declared back in service at 15:50, following retubing.
Mar 12 NAPS-1 (India) first criticality.
Apr 1 20 kWth SLOWPOKE Reactor at AECL Medical Products (now MDS Nordion) in Kanata shut down.
Jun 3 Pickering-3 shut at 21:00 for retubing. {COG}
Sep 12 2 MWth SLOWPOKE Demonstration Reactor (SDR) at Whiteshell Laboratories shut down.
Nov 5 Darlington-2 attained first criticality.
Nov 8 IMPELA-10/50 accelerator achieved 50 kW.
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Jan 15 Darlington-2 generated its first electricity.
Jan 23 Software error in a programmable logic controller caused the Bruce-4 east-face fuelling machine bridge to release its brake and drop 0.4 m.   The machine was latched onto channel C8 at the time, but the channel sealing plug had not been removed.    The channel end fitting was damaged and leaked at a maximum of 1400 kg/hr, declining to 18 kg/hr after the system was depressurized.   The leaking heavy water was collected by normal recovery methods.   Tritium releases were above normal but less than 1% of regulatory allowances.   The channel was buckled and required defuelling and replacement.
Oct 5 100 Wth Pool Test Reactor (PTR) at Chalk River Laboratories shut down.
Oct 9 Darlington-2 declared in service.
Oct 29 Darlington-1 attained first criticality.
Dec 1 Darlington-2 pump impeller and reactor resonance problem discovered.
Dec 19 Darlington-1 generated first electricity.
Dec 28 KEPCO (Korea) signed contract with AECL for Wolsong-2.
  NRU began conversion from high-enriched (HEU) to low-enriched (LEU) fuel.   Completed in 1992.
Jan 1 NAPS-1 (India) declared in-service.
Jan 10 Wolsong-2 (Korea) contract effective
Aug 15 Pickering-3 declared in service after retubing.
Aug 15 Pickering-4 shut for retubing.
Oct 24 NAPS-2 (India) attained first criticality.
Jan 29 NRX shut down for last time {CAC}.
Jul 1 NAPS-2 (India) declared in-service.
Aug Wolsong-2 (South Korea) construction licence
Sep 3 KAPS-1 (India) attains first criticality.
Sep 18 Contract signed for Wolsong Units 3 and 4 (South Korea).
Sep 25 First Wolsong-2 (South Korea) containment concrete poured
Sep 30 Contract effective for Wolsong 3 and 4 (South Korea).
Nov 9 Darlington-3 attained first criticality.
Nov 14 Darlington-1 declared in-service.
Dec 7 Darlington-3 generated first electricity.
Feb 14 Darlington-3 declared in service.
Mar 7 Pickering-4 synchronized to grid after retubing. {COG}
Mar 13 Darlington-4 attained first criticality.
Mar 14 Pickering-4 attains 100% power after retubing. {COG}
Mar 5 Bruce A and B reactors derated to 60% full power, to immediately address concerns regarding a potential reactivity insertion during a low-probability reactor inlet header loss of coolant accident. Further analysis and hardware fixes allowed the reactor power to be increased to ~89% (Bruce A) and ~92 to 95% (Bruce B) of original full power. {NW, various}
Mar 7 Pickering-4 in service after retubing. {COG}
Apr 8 Decision to decommission NRX {CAC}
Apr 17 Darlington-4 first synchronized to grid at 16:17.
May 6 KAPS-1 (India) declared in service.
Jun 14 Darlington-4 declared in service.
Jul First time all 8 Pickering reactors working at the same time, following retubing.
Aug 12 Start of excavation for Wolsong-3 (South Korea).
Jan 17 Ontario Hydro (now Ontario Power Generation) had 19 reactors on line for the first time.
Feb Wolsong-3 and 4 (South Korea) construction licences
Mar 17 First concrete poured at Wolsong-3.
Jun 17 The international Convention on Nuclear Safety was adopted by the International Atomic Energy Agency (IAEA).
Jul 22 First concrete poured at Wolsong-4.
Sep 20 The international Convention on Nuclear Safety was opened for signatures, and was signed by Canada and other countires. (IAEA)
Oct 7 Pickering-7 completed world record continuous operation of a reactor - 893 days. (COG)
Oct 12 Bertram N. Brockhouse received a joint Nobel Prize in Physics for the development of neutron spectroscopy (CRL in the 1950s).
Dec 10 Pickering-2 had a loss-of-coolant accident at 17:27, due to a valve failure external to the core.   The reactor was shut down with no damage to the core.   It was the first ever use of the emergency coolant injection system in a CANDU reactor.    Reactor was restarted following an investigation and repairs.
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Jan 8 KAPS-2 (India) first criticality.
Feb 8 HANARO research reactor (South Korea) first criticality 16:09.   This reactor design was based in part on AECL's MAPLE technology.
Mar 4 KAPS-2 (India) first synchronization to grid.
Apr 7 HANARO research reactor (South Korea) officially opened.
May 29 First Cernavoda-1 (Romania) fuel bundle loaded 22:30
Jun 4 Last of 4560 Cernavoda-1 fuel bundles loaded 16:00
Jul 15 Commissioning of AECL's first MACSTOR unit begins at Gentilly-2 (Québec).
Jul 19 Cernavoda-1 primary circuit loaded with heavy water
Sep 1 KAPS-2 (India) declared in service.
Sep 30 MACSTOR spent fuel loading begins at Gentilly-2 (Québec).
Oct 8 Bruce-2 mothballed.
Dec 12 The international Convention on Nuclear Safety, developed by the IAEA, was ratified by Canada.
Jan 23 Pickering dry fuel storage opened.
Apr Cernavoda-1 (Romania) operating licence granted
Apr 2 Pickering-4 shut for maintenance at 21:43, but stays shut for refurbishment.
Apr 16 Cernavoda-1 attained first criticality at 17:32.
Jul 11 Cernavoda-1 first synchronized with the grid at 18:23.   It was operating at 12% full power.
Jul 18 Cernavoda-1 reached 25% full power and completed load rejection test.
Jul 20 Cernavoda-1 completed loss-of-class IV (normal ac supplies) power test.
Aug 1 Cernavoda-1 reached 50% full power.
Aug 31 Cernavoda-1 reached 75% full power.
Oct 2 Cernavoda-1 attained first full power.
Oct 24 The international Convention on Nuclear Safety (IAEA) came into effect in Canada and other signatory nations.
Nov Wolsong-2 (South Korea) operating licence granted
Nov 6 Wolsong-2 start of fuel loading
Nov 26 Qinshan (China) contract for two CANDU-6 reactors signed.
Dec 2 Cernavoda-1 declared in service.
Jan 27 Wolsong-2 first criticality at 15:23.
Feb 12 Qinshan (China) contract for two CANDU-6 reactors effective .
Mar 17 Ground-breaking ceremony at Qinshan site (China).
Apr 1 Wolsong-2 first grid synchronization.
Apr 4 Bruce-1 shut down at 22:24.   The decision to mothball the reactor for future rehabilitation was made on Oct 17 1997.
Apr 8 Wolsong-2 (Korea) attained 40% power for the first time.
Apr 28 Wolsong-2 (Korea) attained full power for the first time at 17:36.
Jul 1 Wolsong-2 (Korea) declared in service.
Aug 12 Independent Integrated Performance Assessment of Ontario Hydro nuclear stations presented to Ontario Hydro Board.   Outcome of this critical report is the planned shut down of 7 reactors at Bruce A and Pickering A for refurbishment (Bruce-2 already mothballed).
Sep 18 SLOWPOKE-2 at L'Ecole Polytechnique (Montréal) attained first criticality with new core at 13:05.
Oct CIRUS research reactor (India) shut for refurbishment {BARC}
Oct 17 Decision made to mothball Bruce-1.
Dec Wolsong-3 (South Korea) operating licence granted
Dec 27 Pickering-3 shut for refurbishment at 23:48.
Dec 28 Pickering-1 shut for refurbishment at 22:55.
Dec 29 Pickering-2 shut for refurbishment at 22:20.
Dec 30 Start of fuel loading at Wolsong-3.
Jan 7 Wolsong-3 first fuel load complete.
Feb 20 Wolsong-3 first criticality 11:00.
Mar 16 Bruce-4 laid up for refurbishment. {BP}
Mar 25 Wolsong-3 first synchronization to grid at 15:10.
Apr 9 Bruce-3 laid up.   This was the last of 4 Bruce-A reactors shut for refurbishment. {BP}
Apr 20 Wolsong-3 (Korea) attained full power for the first time.
Apr 29 Official opening of the Sudbury Neutrino Observatory
Jun 7 Qinshan-4 and -5 (China) construction licence granted
Jun 8 First containment concrete at Qinshan-4 (China).
Jul 1 Wolsong-3 declared in service, on schedule, 69 months after the contract was signed.
Sep 3 The first eight CANFLEXTM fuel bundles used in a CANDU were loaded into Point Lepreau as part of a normal channel refuelling.
Sep 25 First containment concrete at Qinshan-5 (China) {AECL}.
Oct 23 Pouring the concrete for the Qinshan-4 (China) containment building wall was completed in 17 days 22 hours.  The circular wall is 42.29 m tall and has a concrete volume of 6550 m3.
Feb 1 The continuous pour of concrete for the Qinshan-5 (China) containment building wall (42.29 m tall) was completed at 13:45.   The total elapsed time of 14 days 4 hours is the record for a CANDU-6 plant.   The circular wall was slip formed (the concrete form was moved upwards as the concrete pour progressed) and rose at an average rate of 0.12 m/hour, with a maximum rate of 0.25 m/hr in a region with fewer embedded parts and less rebar.
Feb 8 Wolsong-4 (South Korea) operating licence granted. Fuel loading commenced.
Feb 23 Process of fuel loading and installing shield and closure plugs in Wolsong-4 (South Korea) completed.
Mar 26 First four high-burnup CANFLEX bundles discharged from Point Lepreau.   Twelve CANFLEX bundles remained in operation in this first test of the new fuel format.
Apr 1 Launch of Ontario Hydro’s five successor companies, one of which is Ontario Power Generation (OPG).
Apr 10 Wolsong-4 (South Korea) first criticality 10:43.
Apr 15 Calandria vessel for Qinshan-4 (China) loaded on a ship at ALSTOM Canada Inc., in Tracy, P.Q.
May 21 Wolsong-4 (South Korea) first grid synchronization 11:02.
Jun 4 Wolsong-4 (South Korea) first full power 15:00.
Jun 17 Calandria vessel for Qinshan-4 (China) unloaded in Shanghai.
Jun 23 Condenser for Qinshan-4 (China) unloaded in Shanghai. {AECL}
Jun 25 19:00 - First time all four Wolsong CANDU 6 reactors (South Korea) ran at full power. {AECL}
Jul Installation of fuel channels in Cernavoda-2 (Romania) completed. {AECL}
Aug 8 Final CANFLEX bundles of the Point Lepreau Demonstration Irradiation were loaded at 14:20.   The first time an entire CANDU channel was fuelled with CANFLEX fuel. {AECL}
Aug 12 Operating licences granted by the AECB for the new MAPLE 1 reactor and the new Processing facility at AECL's Chalk River Laboratories.
Aug 27 Installation of the 380 calandria tubes in Qinshan-5 (China) calandria vessel was completed in 10 days at the Alstom plant (Tracy, P.Q.).   This is a record time. {AECL}
Sep 24 Kaiga-2 (India) first criticality at 14:51.
Sep 30 Tokaimura (Japan) fuel processing plant criticality accident.
Oct 1 Wolsong-4 (South Korea) declared in service.
Oct 4 At 19:00 Wolsong-3 (South Korea) had a spill of 45 litres of heavy water, during work on a moderator pump while the plant was shut down for maintenance.   No water escaped containment, but 22 employees received low radiation doses ranging up to 4.5 mSv (50 mSv is the maximum allowable annual limit for a nuclear worker).  Heavy water is not naturally radioactive, but some of the heavy hydrogen atoms absorb neutrons (becoming radioactive tritium) and there are also some activated corrosion products in the heavy water.
Nov 30 Calandria vessel for Qinshan-4 (China) lifted into place. {AECL}
Dec 2 Kaiga-2 (India) first connected to the grid at 20:01.
Dec 24 Rajasthan-3 (India) first criticality (NPCIL)
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Jan 14 Arrival of test bundles of American mixed oxide (MOX) fuel at AECL's Chalk River Laboratories.   This fuel, containing about 3% weapons-grade plutonium surplus to American nuclear weapons (the remainder of the fuel is the usual uranium oxide), is to be tested in the NRU research reactor to see if MOX from weapons-grade Pu can be used in a CANDU reactor.    The tests are part of a Canadian government proposal to reduce worldwide weapons plutonium by "burning" it in reactors.   The utilisation of MOX in power reactors would use up much of the plutonium, denature the remainder (contaminate it with non-weapons plutonium isotopes), and contaminate it with fission products (the radioactive waste in used reactor fuel).   All while generating electricity.
Feb 19 MMIR-1, the first of two new MAPLE medical isotope production reactors at Chalk River Laboratories, attained first criticality at 2:53 a.m.   This is the world's first reactor of the new millenium.   The two MAPLE reactors at CRL, and the associated processing plant, are for medical isotope processing for MDS Nordion.   The new reactors will replace the medical isotope production presently done in the NRU reactor.
Mar 8 First concrete pour for Tarapur 3 and 4 (India), a twin-unit (540 MWe gross each) PHWR station of indigeneous design.
Mar 10 Rajasthan-3 (India) first grid connection 16:21.
Mar 16 Kaiga-2 (India) declared commercial.
Apr 5 Pressurizer installed in Quinshan-1 (China).
May 11 MMIR-1 received permission from the AECB to operate at up to 500 kW.   At full power, MMIR-1 and -2 will operate at 10 MW(th).
May 31 The Canadian Nuclear Safety Commission came into law, superceding the Atomic Energy Control Board
Jun 1 Rajasthan-3 (India) declared commercial.
Jun 26 The prototype Combined Industrial Reforming and Catalytic Exchange (CIRCE) heavy water production facility, built in co-operation with Air Liquide Canada (ALC), officially opened at ALC's site in Hamilton, Ontario.
Jul 7 Following hearings on Jun 29, 2000, the Canadian Nuclear Safety Commission (CNSC) approved an amendment to authorize the operation of MDS Nordion's MAPLE 2 reactor (10 MW pool reactor for medical radioisotopes production).
Jul 11 Announcement of the lease of Ontario Power Generation's (OPG) Bruce A and B reactors to a consortium called Bruce Power led by British Energy.    OPG is required by law to reduce its share of Ontario's electricity to 35% (from the present 85%) by 2010.
Aug 7 The final four CANFLEX bundles of the 2-year, 24-bundle Point Lepreau Demonstration Irradiation were discharged.
Sep 25 Arrival of Russian test bundles of mixed oxide (MOX) fuel at the Chalk River Laboratories of AECL (see Jan 14 2000).   This fuel, about 3% plutonium surplus to Russian nuclear weapons plus uranium oxide, is to be tested in the NRU research reactor.
Sep 26 Kaiga-1 (India) first criticality at 10:34.
Oct 12 Cameco Corporation announced a memorandum of understanding with British Energy PLC whereby Cameco will acquire a 15% interest in Bruce Power.   Bruce Power is the consortium, led by British Energy, that has signed an agreement to lease Ontario Power Generation's (OPG) Bruce A and B reactors.
Oct 12 Kaiga-1 (India) first grid connection 11:34.
Nov 3 Rajasthan-4 (India) first criticality at 03:53.
Nov 16 Kaiga-1 (India) declared commercial.
Nov 17 Rajasthan-4 (India) connected to the grid at 07:35.
Dec 23 Rajasthan-4 (India) declared commercial.
Feb 3 Beginning of the test of mixed oxide (MOX) fuel bundles at AECL's Chalk River Laboratories, as the NRU reactor went critical at 8:00 am.   This fuel, containing about 3% weapons-grade plutonium surplus to Russian and American nuclear weapons (the remainder of the fuel is the usual uranium oxide), is being tested in the NRU research reactor to see if MOX from weapons-grade Pu can be used in a CANDU reactor.
Mar 31 First reactor grade heavy water produced at the prototype Combined Industrial Reforming and Catalytic Exchange (CIRCE) heavy water production facility in Hamilton, Ontario.
Apr 6 Bruce Power committed to refurbish and restart Bruce reactors 3 and 4, at an estimated cost of $CDN 340 million. {BP}
May 12 The contract, for Bruce Power to lease the eight reactors at Bruce from Ontario Power Generation, was closed (See Oct 12, 2000).   The Canadian Nuclear Safety Commisison granted Bruce Power an operating licence. {BP}
Jun 18 Researchers at the Sudbury Neutrino Observatory announced the first official results of their experiment.   The SNO study has shown that there is no discrepancy in the quantity of neutrinos reaching the earth; rather, the type of neutrinos created in the Sun have a mass and can change from one variety to another along the journey to Earth. {SNO}
Sep 5 Wolsong-1 completed a run of 454 days, a record (to date) for the CANDU 6 design {COG}
Nov 2 British Energy and Atomic Energy of Canada Limited signed an agreement on work to assess the feasibility of CANDU technology as a potential nuclear power station option in the UK.   British Energy Chair Dr. Robin Jeffrey announced in Oct 2001 that British Energy intended to "replace nuclear with nuclear", in reference to its Advanced Gas Reactors (AGR), which will reach the end of their licences over the next two decades.   Unless new power reactors are built in the UK, nuclear-generated electricity will fall from a 25% share at present to 3% by 2020. {AECL}
Nov 5 Canadian Nuclear Safety Commission approved Ontario Power Generation's application to amend its licence for the re-start of the four Pickering A reactors.   The CNSC must be satisfied with the upgrade and refurbishment work, and the fitness for re-start, prior to granting OPG approval to raise power on each of the reactors. {CNSC}
Nov 7 Hitachi Ltd. and AECL signed a Memorandum of Agreement on developing the NG (Next Generation) CANDU.   Hitachi will concentrate on the turbine generator system, while AECL will focus on the nuclear steam plant. {AECL}
Feb 25 New Brunswick Power filed its evidence with the Public Utilities Board (PUB) seeking a recommendation to refurbish the Point Lepreau Generating Station.   NB Power is proposing to retube the reactor and refurbish other components in order to extend the station's life to 2032.   The project cost is estimated at $845 million and the refurbishment outage would occur from Apr 2006 to Sep 2007. This was later revised to the outage starting in April 2008. See the Refurbishment web site.
March 30 First concrete poured for Kaiga-3 (220 MWe PHWR in India). {NPCIL}
Apr Bruce Power Unit 5 achieved the highest lifetime output for a CANDU reactor (surpassing mothballed Bruce unit 3) with over 110 million MWh (gross) produced since Dec 1984 (lifetime capacity factor of 79% to date).   The net electricity produced by Bruce 5 electricity would be sufficient for all Canada for over 2 months at present consumption rates.   A total of 6 CANDU reactors have passed the 100 million MWh (gross) mark, to Nov 6 2002. {MJB, BP}
Apr 2 Federal Environment Minister David Anderson announced he has determined that the Whiteshell Laboratories Decommissioning Project is not likely to cause significant adverse environmental effects, and that no further environmental assessment by a review panel or a mediation is warranted.
May 20 Qinshan-4 (China) moved to a full operations shift in preparation for hot conditioning and fuel loading. {AECL}
Jun 1 Nuclear Power Demonstration (NPD) reactor designated a provincial heritage site by the Ontario Heritage Foundation.
Jun 13 Canadian Nuclear Fuel Waste Act given royal assent.
Jul 18 First fuel loading began at Qinshan-4 (China). {AECL}
Aug 13 First fuel loading and addition of heavy water to Qinshan-4 (China) complete. {AECL}
Sep 19 Containment dome pre-stressing completed for Cernavoda-2 (Romania) {AECL}
Sep 20 First criticality at Qinshan-4 (China) at 22:08. This is just over 51 months from first construction concrete and is the shortest construction of any NPP built in China. Photo available of Qinshan-4 startup (76 kB)here {AECL}
Oct 9 Opening of the Western Used Fuel Dry Storage Facility, at the Bruce reactor site in Ontario. The cannisters will be used for storing used CANDU fuel bundles from the Bruce reactors. {OPG}
Oct 30 CIRUS research reactor (India) restarted after refurbishment {BARC}
Nov 6 At 23:47 Wolsong-1 (Korea) became the first CANDU 6 reactor to attain a lifetime production of 100 million MWhe (gross) since first producing electricity. In that time period (7251 days) its average capacity factor was 84.75%. {COG}
Nov 9 First steam to the turbine at Qinshan-4 (China). {AECL}
Nov 15 Canadian Nuclear Fuel Waste Act (Officially "An Act Respecting the Long-Term Management of Nuclear Fuel Waste") in effect. The legislation calls for nuclear utilities to form the Waste Management Organization (WMO, later established as the Nuclear Waste Management Organization (NWMO)), which will report regularly to the Government of Canada. The Nuclear Fuel Waste Bureau is the oversight organization run by Natural Resources Canada {NRCan}.
Nov 18 First electricity produced by Qinshan-4 when it was synchronized to the grid at at 17:30. The reactor power was 25% and the TG was loaded to 8% power or 58MWe {AECL}.
Dec 5 Installation of the Cernavoda 2 lower feeders officially completed. {AECL}
Dec 5 KANUPP (Pakistan) closed at end of 30-year design life. Work ongoing to extend plant life by 15 years. {NW/COG}
Dec 15 At 07:24 Wolsong-1 (Korea) became the first CANDU 6 reactor to attain a lifetime production of 100 million MWhe (gross) since being declared in commercial operation on Apr 22, 1983. In that time period (7178 days) its average capacity factor was 85.62%. {COG}
Dec 17 Qinshan-4 (China) attained full power for the first time at 18:18. {AECL}
Dec 19 Canadian Nuclear Safety Commission announces 6-year licence for AECL's Whiteshell Laboratories. This licence is the first overall site decommissioning license issued for a Canadian nuclear research and test establishment. {CNSC}
Dec 23 TransCanada Pipelines Ltd, Cameco, BPC Generation Infrastructure Trust (a trust established by Ontario Municipal Employees Retirement System), the Power Workers' Union and The Society of Energy Professionals announced an agreement to purchase the British Energy stake in Bruce Power. The unions and Cameco are already part owners of Bruce Power.
Dec 31 Qinshan-4 (China) entered commercial service at 17:16. {Xinhua}
Jan 2 Qinshan-5 (the second CANDU in China) moderator loaded. (COG}
Jan 3 Canada's Export Development Canada signed an agreement to guarantee a portion of the financing for completion of Cernavoda-2 (Romania).
Jan 5 Qinshan-4 (China) provisionally accepted.   This was 38 days earlier than the contract specified. {AECL}
Jan 14 At 18:53, fuel loading process began at Bruce-4, in preparation for restart {BP}
Jan 29 Successful completion of the Qinshan-5 reactor containment leak test.   During the test the containment was pressurized to more than one atmosphere (gauge).   The leak rate was 0.13% of containment volume per day, the lowest leak rate of any CANDU containment tested to date. {CNA}
Feb 11 At 02:45, MAPLE-1 attained 1 MWth (10% full power) for the first time {JW}
Feb 11 Qinshan-5 heat transport system hot conditioning completed {COG}
Feb 12 At 23:09, MAPLE-1 attained 2 MWth (20% full power) for the first time {JW}
Feb 21 Darlington station granted first-ever 5 year licence for a CANDU in Canada.
Mar 7 Pickering-4 primary system re-pressurized for the 1st time since reactor shut down for refurbishment and upgrading in Apr 1996 {OPG}
Mar 8 At 03:31 Point Lepreau attained 100,000,000 MWhe (gross) since generating its first electricity on Sept 11 1982.   This is the second CANDU 6 to attain this mark, after Wolsong-1 on Nov 6 2002.   The lifetime performance of Point Lepreau is 81.89% to this date, including the pre-commissioning low power period. {NBP}   To this date seven CANDUs have exceeded the 100 million MWhe lifetime mark.
Mar 15 Qinshan-5 loss of class IV electrical test completed {COG}
Mar 16 20:50 First fuel loading at Qinshan-5, taking until Mar 22 to complete {COG & Interfax-China}
Mar 27 First on-power fuelling loading at Qinshan-4. {Xinhua}
Mar 29 Fugen prototype reactor (Japan) shut permanently. The 165 MWe heavy-water moderated, boiling light water reactor was the last of this type; the other two were the Steam Generating Heavy Water Reactor (SGHWR) in the UK (shut in 1990), and Gentilly-1 CANDU Boiling Light Water Reactor (BLWR) in Québec (last operated in 1977 and shut permanently in 1979). {AP}
Mar 31 The last one of four small power reactors at Calder Hall (UK) closed after 46 years operation.
Apr 4 The CNSC granted Bruce Power a licence amendment to restart Bruce 3 and 4, pending completion of several tasks. {BP, CNSC}
Apr 16 Nuclearelectrica, Atomic Energy of Canada Limited and Ansaldo Italia signed a commercial contract to complete and start-up Cernavoda-2 (Romania). Work has been continuing on the station at a lower pace for several years {BBC}
Apr 20 Fuel loading process began at Bruce-3, in preparation for restart {BP}
Apr 29 Qinshan-5 (the second CANDU 6 in China) achieved first criticality at 23:28, 52 days ahead of schedule. {CNA, COG}
May 4 CNSC authorized lifting Guaranteed Shutdown State on Pickering-4 at 20:00, in preparation for restart. This will allow operation at up to 1% full power to test systems. {CNSC}{OPG}
May 5 Guaranteed Shutdown State lifted on Pickering-4 at 07:30, in preparation for restart after extensive refurbishment and rebuilding. {OPG}
Jun 11 Qinshan-5 (China) achieved first grid synchronization 11:24, 36 days ahead of schedule. {COG}
Jul 6 Pickering-4 attained criticality. Pickering-4 last operated on Apr 2, 1996, when it was shut for the installation of a second shutdown system. {OPG}
Jul 9 Qinshan-5 (China) achieved first full power at 02:00. {COG}
Jul 23 MAPS-2 (India) returned to service after an 80-week planned outage for retubing.
Jul 24 Qinshan-5 (China) declared commercial at 00:18, four months ahead of schedule. {AECL}
Jul 28 MACSTOR facility officially opened at Cernavoda site (Romania), for dry storage of spent fuel from the Cernavoda-1 reactor {AECL}
Aug 14 Largest grid blackout in North American history began - over 100 electrical power plants tripping off line between about 16:10 and 16:25 EDT. About 50 million people without electricity in Connecticut, Massachusetts, Michigan, New Jersey, New York, Ohio, Ontario, Pennsylvania and Vermont. Deep River, Chalk River and Petawawa, Ontario, stayed powered due to rapid disconnect from the remainder of the grid and supply from Ontario Power Generation's Des Joachims hydro dam to AECL's Chalk River Laboratories. Bruce-5, 7 and 8 were reconnected to the grid at 21:04, 21:14 and 19:14; Darlington-3 was reconnected at 21:18. {CNA, IMO, OPG}
Aug 17 Darlington-2 reconnected to the grid at 20:36 following the blackout {OPG}
Aug 18 Darlington-1 & 4 reconnected to the grid at 03:15 and 11:12, respectively, following the blackout {OPG}
Aug 19 CNSC authorized lifting Guaranteed Shutdown State on Bruce-4, in preparation for restart. This allows operation at up to 1% full power to test systems. {CNSC, BP}
Aug 21 Pickering-4 synchronized to grid for first time since Apr 2 1996, following extensive refurbishment; it reached about 15% full (reactor) power and was preparing for first grid connection when the blackout hit on Aug 14. Pickering-5 also synchronized to grid following the blackout. {CNA}
Aug 22 Pickering-8 synchronized to grid following the blackout.
Aug 23 Bruce-6 synchronized to grid at 02:03 following blackout. {BP}
Aug 24 Cernavoda-1 (Romania) shut due to very low water levels in the Danube, caused by severe Europe-wide drought. The water is used primarily for the condenser. The warmer and lower flow in rivers throughout much of Europe caused many thermal power plants (fossil-fired and nuclear) to reduce output, shut down, or get temporary permission to raise outlet water temperatures. Seaside plants were unaffected.
Aug 25 Pickering-6 synchronized to grid following the blackout. {CNA}
Aug 26 Pickering-4 authorized to raise power from 30 to 60%. {CNSC}
Aug 28 The Reactor Shutdown Guarantees (RSGs) were removed from Bruce-4 at 00:37, in preparation for re-start following refurbishment. Bruce-4 last operated Jan 19, 1998. {BP}
Aug 29 Pickering-7 synchronized to grid and OPG generating capacity fully restored following blackout {OPG}
Aug 30 At 13:15 Bruce-4 attained first criticality since refurbishment {BP}
Sep 11 Bruce-4 completed phase B commissioning {BP}
Sep 15 First fuel loaded into MAPLE-2 (Isotope production reactor at CRL) at 15:40.
Sep 19 Cernavoda-1 (Romania) synchronized to the grid at 12:45, after being shut since Aug 24 due to very low water levels in the Danube, caused by the severe Europe-wide drought. Rains have since caused the Danube to rise. {NN}
Sep 25 Pickering-4 declared commercial following re-start.
Oct 7 At 10:37 Bruce-4 attained first grid connection since refurbishment {BP}
Oct 8 Embalse achieved a continuous run of 459 days, the longest for a CANDU 6 {COG}
Oct 9 At 14:08, MAPLE-2 attained first criticality. MAPLE 2 is at AECL's Chalk River Laboratories, on the site where Canada's first reactor, ZEEP, was located (and first went critical on Sep 5, 1945). {JW}
Nov 29 KANUPP (Pakistan) first criticality following life extension assessment and major overhaul.
Dec 8 At 17:19 Bruce-3 attained first criticality since refurbishment {BP}
Dec 22 Bruce-4 declared commercial following re-start.
Jan 8 At 22:47 Bruce-3 attained first grid connection since Apr 9, 1998, when it was shut for refurbishment {BP}
Jan 22 KANUPP re-connected to grid following 14-month outage for overhaul and assessment {COG}
Jan 28 For the first time since Aug 16, 1997, the Bruce site had six reactors in operation simultaneously {IEMO}
Jan 31 For the first time since Dec 13, 1997, Ontario had 14 reactors connected to the grid simultaneously {IEMO}
Feb 8 RAPS-1 (India) re-synchronized with grid after 21-month outage for life extension work {NPCIL}
Feb 26 For the first time since Sep 4, 1997, Ontario had 15 reactors connected to the grid simultaneously {IEMO}
Mar 19 Former deputy Prime Minister John Manley releases OPG Review Committee report. Amongst other things, report recommends maintaining public control of the utility, partnerships with private enterprise, refurbishment of Pickering 1 and possibly units 2 and 3, shut coal-fired generation, and new nuclear generation.
Mar 28 Bruce-3 declared commercial following re-start.
Jun 29 Chapelcross Magnox nuclear station closed after 45 years of operation. The 240 MWe gross (4 reactors) station started Jan 1959.
Aug 9 Mihama-3 PWR (Japan). 0.56 m diameter pipe, between low pressure feedwater heater and moisture separator, burst at 15:28. Four workers killed and 7 inured by 140oC water flashing to steam. Reactor shut automatically; no radiation released because it was a failure on the secondary (turbine) side of power plant.
Aug 13 Secondary side condensers at Cernavoda-2 (Romania) tested as part of commissioning process. {Rompres}
Aug 30 Embalse (Argentina) attains 100 million MWhe (gross) since first synchronization on Aug 25, 1983. {COG}
Oct 10 Commissioning of Cernavoda-2 (Romania) commenced with energization of main service transformer. Project 74% complete. {AECL}
Oct 22 Canadian Light Source 2.9 (GeV) synchrotron officially opened at University of Saskatchewan.
Dec 3 Bruce Power's Station A Restart was recognized as one of Power Engineering magazine's "Projects of the Year". {BP}
Top of Page
Jan 21 At 17:31 Gentilly-2 had generated 100 million MWh of electricity (gross) since being declared in commercial operation on Oct 1, 1983.    This is equivalent to more than 60% of Quebec's annual consumption in 2004, and to 220 days of average production from all Hydro-Quebec's generating stations.   98,700 fuel bundles were used to generate that much electricity. {COG}
Feb 1 First fuel loading was completed at Tarapur-4, a 540 MWe (gross) PHWR designed and built in India.
Mar 6 First criticaly Tarapur-4, at 12:42 and 7 months ahead of schedule {NPCIL}.
Mar 26 Qinshan-5 began first planned outage {COG}.
Jun 4 Tarapur-4 first connected to grid at 23:25 {NPCIL}.
Jun 16 Pickering-1 repressurized (cold) for first time since it was shut in Dec 1997, as part of re-start process {OPG}.
Jun 24 Pickering-1 passed its reactor building pressure test {OPG}.
Jun 29 Pickering A receives 5-year licence {COG}.
Jul 28 Pickering-1 granted permission by Canadian Nuclear Safety Commission to remove guaranteed shutdown state in preparation for first criticality {OPG}.
Jul 29 The New Brunswick government announced its decision to proceed with the refurbishment of Point Lepreau. AECL is the prime contractor. {NB Government} More refurbishment details here.
Aug 2 Pickering-1 attained 1st criticality at 10:05 pm following refurbishment {OPG}.
Aug 12 Decision by Ontario Power Generation not to proceed with restart of Pickering-2 and 3, due to the business case {OPG}.
Sep 9 Pickering-1 primary heat transport system heated to operating temperature of 265°C, as part of the restart process {OPG}.
Sep 12 Tarapur-4 (India) declared in commercial operation {NPCIL}.
Sep 26 Pickering-1 connected to the grid at ~18:00, the first time since it was shut on 22:55 Dec 28, 1997 {OPG}.
Oct 14 Pickering-1 reactor trip test performed, taking the unit from 60 per cent full power to zero power. This marks the completion of one of the final milestones of the restart project {OPG}.
Oct 17 Bruce Power announces major refurbishment and restart project for entire Bruce A plant. The project will include the replacement of all the fuel channels and steam generators of Bruce units 1 and 2, and later move to units 3 and 4. Bruce 3 and 4 are presently operating, having been reconnected to the grid on Jan 8 2004 and Oct 7 2003, respectively. {BP}
Nov 3 Pickering-1 declared in commercial service following restart {OPG}.
Dec 21 Containment pressurization test at Tarapur-3 successfully complete, as part of commissioning testing {NPCIL}.
Feb 5 For the first time since Aug 11, 1997, Ontario had 16 reactors connected to the grid simultaneously {IEMO}
May 11 Bruce-7 net output increased to 825 MWe {BP}
May 21 First criticality Tarapur-3, an Indian 540 MWe (gross) PHWR, at 10:44 and two months ahead of schedule {NPCIL}.
Jun 2 Natural Resources Canada announced $520 million funding over 5 years to begin the clean up of the legacy waste at AECL's sites. These wastes include those from before AECL was incorporated, from universities and hospitals, government and industry, and R&D programs in support of Canada's nuclear industry. {NRCan}
Jun 13 Ontario Energy Minister Dwight Duncan directed Ontario Power Authority to proceed with its recommended 20-year electricity supply mix plan, with some revisions. Ontario Power Generation will undertake feasibility studies for refurbishing units at Pickering and Darlington, and also begin an environmental assessment for construction of new units at an existing nuclear facility. See press release. {Ont Min of Energy}.
Jun 15 First grid connection of Tarapur-3 {NPCIL}
Jun 24 Gentilly-2 accomplishes 365 days of uninterrupted output, the first time in its history {COG}
Jun 30 Criticality of MAPLE 1 at 22:29, for low power testing {AECL}.
Jul 6 First use of CANFLEX low void reactivity fuel bundles in Bruce unit 7, for testing. The 4 test bundles have 43 fuel elements (instead of 37), use slightly enriched uranium (1% uranium-235 instead of the natural 0.7%), have a dysprosium-doped centre fuel element, and additional appendages to enhance heat transfer. All these features increase the reactor safety margins {AECL}.
Aug 3 First replacement steam generators, for the Bruce 1 and 2 refurbishment, arrived at Bruce unit 2 from Babcock and Wilcox Canada, Cambridge, Ontario. A second steam generator arrived August 10. {BP}
Aug 17 Bruce Power filed an application with the Canadian Nuclear Safety Commission (CNSC) to prepare a site for the potential construction of new reactors at its Bruce County facility. {BP}
Aug 18 Tarapur-3 declared commercial {NPCIL}
Sep 22 Ontario Power Generation filed an application for a Site Preparation Licence for new nuclear units at its Darlington site {OPG}
Oct 12 First feeders disconnected from Bruce-2 in Bruce A refurbishment project. Fifth new steam generator received from Babcock and Wilcox Canada {BP}
Oct 17 First fuel shipped to Cernavoda-2 (Romania) from the Pitesti Nuclear Fuel Plant {WNA}
Nov 3 Cernavoda-2 (Romania) successfully completed containment pressurization test {Rompres}
Nov 29 Last closure plugs removed from Bruce-2 in Bruce A refurbishment project {BP}
Dec 1 Last feeders disconnected from Bruce-2 {BP}
Dec 10 Cernavoda-2 began hot testing (unfuelled) {NucNet}
Jan 18 AECL's National Research Universal (NRU) research reactor attained 1 million MW days since the last calandria vessel change. NRU re-entered service on August 2 1974, following a two-year shutdown for refurbishment. {AECL}
Feb 14 First fuel loaded in Cernavoda-2, the second Romanian CANDU 6 reactor, at 01:29. {SNN}
Feb 19 Last of 4560 fuel bundles loaded in Cernavoda-2 at 01:30.
Feb 26 Kaiga-3 (220 MWe PHWR in India) first criticality at 10:10. {NPCIL}
March 5 Last lower feeder segment cut out of Bruce-2, as part of the Bruce A refurbishment project. {AECL}
Mar 12 First steam generator removed from Bruce-2, as part of the Bruce A refurbishment project. This is the first time a steam generator has been removed from a CANDU reactor in preparation for replacement. {BP}
Apr 11 Kaiga-3 (220 MWe PHWR in India) first grid connection. {NPCIL}
Apr 30 McMaster Nuclear Reactor (McMaster University, Hamilton) completed conversion from highly enriched uranium fuel to low enriched uranium fuel {Nuclear Canada}
May 6 Cernavoda Unit 2 CANDU 6 first criticality achieved at 23:25:25. {AECL}
May 6 Kaiga-3 (220 MWe PHWR in India) declared commercial at 18:00. {NPCIL}
May 17 First pressure tube severed in Bruce-2, as part of the Bruce A refurbishment project. {BP}
June 15 The National Research Council unveiled Canada’s first neutron reflectometer for the Canadian Neutron Beam Centre. Neutrons are supplied by AECL's National Research Universal (NRU) reactor at Chalk River Laboratories. {NRC/CNRC}
Jun 13 First steam generator replaced in Bruce-2. First ever SG replacement in a CANDU. {BP}
June 29 Last of 480 pressure tubes severed in Bruce-2, at 02:49. {AECL}
Aug 7 Cernavoda-2 (the 11th CANDU 6 in operation worldwide) was connected to the grid for the first time, at 17:21. Reactor power was 25%. {AECL/Nuclearelectrica}
Sept 12 Cernavoda-2 attained 100% full power for the first time, at 03:57. {AECL}
Sept 15 Removal of Bruce 2 end fittings began. {BP}
Sep 26 Cernavoda 2 successfully completed its contractual 10-day full power operation. {AECL}
Oct 5 Cernavoda 2 declared in commercial operation. {AECL}
Oct 25 First steam generator removed from Bruce-1, as part of the Bruce A refurbishment project. {BP}
Nov 18 NRU taken out of service for maintenance and to address licensing issues arising over emergency power supply connections to two coolant pumps. The EPS is a seismically-qualified backup system in addition to other backup power supplies. {AECL}
Nov 23 Removal of Bruce 2 end fittings finished. {BP}
Dec 10 Last steam generator removed from Bruce-1. {BP}
Dec 11 Canadian Parliament passed legislation C-38, with all parties in support, allowing AECL to restart NRU for a 120-day period for medical radioisotope production, while the emergency power system was connected to primary pumps P-104 and P-105. For more detail on the NRU licensing issue, see the Canadian Nuclear FAQ description.
Dec 14 First pressure tube removed from Bruce-2. {BP}
Dec 16 NRU returned to service, 03:44, following commissioning of primary pump P-105 starter motor, connected to seismically-qualified emergency power system. {AECL}
Jan 8 Last new steam generator placed in Bruce-1, completing a total of 16 replacements in B-1 and B-2. {BP}
Feb 2 NRU restarted at 00:40, following commissioning of primary pump P-104 starter motor, conected to seismically-qualified emergency power system. This was 53 days after Dec 11 federal legislation C-38 was passed, which had given 120 days to complete the work. {AECL}
Mar 12 Last of 480 pressure tubes removed from Bruce-2, at 3:15 am. A total of 90 days for the pressure tube removal job. {BP}
Mar 13 Bruce Power Alberta completed a deal to buy the assets of Energy Alberta Corporation relating to nuclear power plant development. {BP}
Mar 28 At 23:00 Point Lepreau (1st CANDU 6) shut for mid-life retube and refurbishment. See the refurbishment web site {NBP}
April 2 Bruce 1 refurbishment: pressure tube severing completed, 19 days ahead of schedule. {BP}
Apr 17 Bruce 2 refurbishment: last of calandria tube inserts removed, permitting calandria tube withdrawal. {AECL}
Apr 24 British Columbia government bans exploration for uranium and thorium. {BC Government}
May 1 Generator rotor from Point Lepreau shipped to the UK for rewinding {NBP}
May 10 Last of 4,560 fuel bundles removed from Point Lepreau {NBP}
May 16 AECL decides to discontinue development of the MAPLE medical isotope reactors. {AECL}
May 21 Removal of Bruce 1 end fittings began. {BP}
Jun 5 Removal of first calandria tube from Bruce 2. {BP}
Aug 11 Removal of Bruce 1 end fittings (including annulus gas tubing) completed. {AECL}
Aug 17 Removal of first Bruce 1 flow restricting outlet bundle. {BP}
Aug 19 Hydro Québec authorizes refurbishment of Gentilly-2, one of the first four CANDU 6 reactors started in 1983. Estimated cost is $CDN 1.9 billion, with shutdown and work to commence in 2011. {HQ}
Aug 31 Removal of last Bruce 1 flow restricting outlet bundle at 09:30 (16 days ahead of schedule). {BP}
Sep 1 Last of 480 calandria tubes removed from Bruce-2. A total of 89 days for the calandria tube removal job. {AECL}
Sep 10 Last of 760 feeder tubes removed from Point Lepreau. {AECL}
Sep 13 The fourth and final rinse of the high pressure service water system was completed in Bruce-2. {BP}
Sep 21 First pressure tube (W05) removed from Bruce-1. {BP}
Nov 20 Last pressure tube (W05) removed from Bruce-1. Job took 59 days, 30 faster than Bruce-2. {BP}
Dec 22 AECL signs contract with Hydro Québec for retubing Gentilly-2. {AECL}
Jan 16 NRU U1 experimental loop recommissioned and ACR fuel testing commenced. The U1 loop is used to subject fuels and materials to high neutron fluxes under power reactor conditions. {AECL}
Jan 23 Calandria tube insert removal complete in Bruce-1. {BP}
Feb 7 First calandria tube removed in Bruce-1. {BP}
Mar 4 Last calandria tube removed in Bruce-1. A total of 26 days for the calandria tube removal job. {BP}
Apr 1 Wolsong-1 (Korea) CANDU-6 shut for retube project, at 16:50. Reactor has produced 131,830 GWh (gross) of electricity since commercial operation began April 22, 1983. {AECL/KHNP}
Apr 2 EnergoNuclear SA was created to build two CANDU-6 reactors in Romania. Seven European utilities and one steelmaker formed the company to construct and operate the AECL-designed 720-MW units, scheduled to come online in 2015-16. {NW}
April Last of 380 pressure tubes removed from Point Lepreau. {NBP}
May 14 Loss of grid in eastern Ontario trips NRU reactor at Chalk River. During restart, a leak of ~5 kg/hr of heavy water was discovered. Restart was halted {AECL}
May 18 NRU leak location determined, from bottom of calandria vessel into J-rod annulus. Extended outage (>1 month) for calandria vessel repair announced. This is an interruption of a major supplier of medical radioisotopes (esp. Mo-99 for Tc-99m imaging diagnostics). {AECL}
May 22 Last molybdenum-99 targets removed from NRU. {AECL}
June 2 First fuel removed from NRU {AECL}
June 15 Last fuel removed from NRU {AECL}
June 15 Wolsong-1 vault turned over to AECL two weeks ahead of schedule, for refurbishment of this CANDU 6 in Korea {AECL}
June 20 First (tube A13) of 480 calandria tubes installed in Bruce-2. {BP}
June 24 Wolsong-1 PHTS vacuum drying completed 7 days ahead of schedule {AECL}
July 1 Bruce-2 turbine generator mechanically complete, as part of refurbishment {BP}
June 29 Ontario government suspends plans to build two more reactors at Darlington.
July 18 Last of 380 calandria tubes removed from Point Lepreau. {NBP}
July 23 Bruce Power withdraws application to build new reactors in Nanticoke, Ontario, due to declining electricity demand. BP will focus on refurbishment Bruce A and B units. {BP}
July 25 Last of 760 feeders removed in Wolsong-1 refurbishment (16 days for all feeders). {BP}
Aug Wolsong 1 Retubing Team completed installation of Fuel Channel Platform in 23 days, 6 days ahead of schedule. {AECL}
Sep 1 Rajastan-2 (200 MWe CANDU in India) restarted after completion of En-Mass Feeder Replacement and performance improvement upgrades. {NPCIL}
Sep 26 Announcement that Point Lepreau refurbishment has been delayed to be complete by Feb 2011. {AECL}
Oct Wolsong 1 Retubing Team completed cutting fuel channel bellows 10 days ahead of schedule. {AECL}
Oct 15 Bruce 2 Retubing Team completed first channel (pressure tube + end fittings) installation (A08). {BP}
Nov 6 Wolsong 1 Retubing Team completed end fitting removal in 20 days. {AECL}
Nov 7 Bruce 2 ion chanber 5 removed. It had a small leak since 1981 and had resisted earlier attempts to be removed. {BP}
Nov 15 Calandria tube in channel C06 is the first to be positioned in Bruce 1. {BP}
Nov 24 RAPS-5 (India), a 220 MWe enhanced and indigeneous Douglas Point type of PHWR, went critical at 12:51. {NPCIL}


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AECB Quoting from the AECB web site: "The Atomic Energy Control Board (AECB) is the federal nuclear control agency, answerable to the Canadian Parliament. It exercises control through a regulatory system that establishes the health, safety, security and environmental standards for uses of nuclear energy including waste facilities and licenses only those activities that can meet and maintain those standards."   The AECB came into being in 1946 with the Atomic Energy Control Act, but under new legislation - the Nuclear Safety and Control Act (NSCA) which came into effect on May 31, 2000 - the AECB will be given a "clear mandate to establish and enforce national standards in the areas of health, safety and environmental consequences of nuclear activities."   The AECB was renamed the Canadian Nuclear Safety Commission (CNSC), which removed the frequent confusion in the media and public between AECL and the AECB. Of course there is now some confusion between the Canadian Nuclear Society (CNS) and the CNSC!
AECL Atomic Energy of Canada Limited, a federal crown corporation established in 1952.   Developer and designer of the CANDU power reactors, MAPLE and SLOWPOKE research reactors, as well as principal nuclear research and development company in Canada.   AECL designed and built ZEEP - the first nuclear reactor outside of the USA. It was followed by a succession of research reactors: NRX, PTR, NRU, ZED-2, WR-1, SLOWPOKE-1 and SDR.   AECL has its main research laboratories at Chalk River, Ontario, 200 km up the Ottawa River (northwest) from Ottawa, and its main engineering site at Sheridan Park in Mississauga (Toronto), Ontario.   AECL also has a research site at the Whiteshell Laboratories, Pinawa, Manitoba, about 100 km east-northeast of Winnipeg, and nearby in Lac du Bonnet is the Underground Research Laboratory.   Both these latter labs are much smaller than originally, and are in the process of being decommissioned.   There is also an engineering office in Montréal and several smaller offices and sites in Canada and around the world.
Browns Ferry-1 American (Athens, Alabama) boiling water reactor that suffered a serious fire to control cabling on Mar 22 1975.   No fatalities, radiation releases nor reactor damage. Reactor upgraded and returned to power. The accident had serious implications for reactor safety, especially with respect to fire, which influenced western reactor design and practices.
Bruce Following the construction and operation of the commercial prototype CANDU reactor - Douglas Point - on the Bruce Peninsula (eastern shore of Lake Huron, near Kincardine, Ontario), another eight larger CANDUs were built there.   Two sets of four reactors were built - Bruce A (first criticalities from Jul 27 1976 to Dec 10 1978) and Bruce B (first criticalities from May 29 1984 to Feb 15 1987).   Each set of four reactors share a common vacuum building.   Each of the Ontario Power Generation (OPG) reactors produces 904 MWe (gross, including some industrial steam production capability, Bruce A) or 915 MWe (gross, Bruce B. Since Jan 1, 1998, the Bruce B reactors are officially listed at 840 MWe gross).

The four Bruce A units were shut and mothballed - due to maintenance, management and safety margin problems - in 1995, 1997 and 1998. Here are the shut down dates with an estimated total net electricity production since the units were declared commercial (each reactor also delivered electricity to the grid prior to being declared commercial):

Bruce-122:24Apr 4 199792,100,000 MWhe
Bruce-2 Oct 8 199576,300,000 MWhe
Bruce-3 Apr 14 1998102,100,000 MWhe
Bruce-411:29Jan 19 199892,450,000 MWhe

OPG was required by law to reduce its share of Ontario's electricity to 35% (from 85% in 2001) by 2010, though this reduction is now unlikely.

On Jul 11, 2000, a consortium led by British Energy announced an agreement to lease and operate OPG's Bruce A and B reactors, under a new company called Bruce Power.   On Dec 23, 2002, TransCanada Pipelines Ltd, Cameco, BPC Generation Infrastructure Trust (a trust established by Ontario Municipal Employees Retirement System), the Power Workers' Union and The Society of Energy Professionals announced an agreement to purchase the British Energy stake in Bruce Power. The unions and Cameco were already part owners of Bruce Power, along with British Energy.   The ownership is now Cameco (31.6%), TransCanada PipeLines (31.6%), BPC Generation Infrastructure Trust (31.6%), and the Power Workers' Union and the Society of Energy Professionals (5.2%).

Bruce Power operates the four Bruce-B reactors, and assessed the four Bruce A reactors to see if they can be economically refurbished and restarted.    Bruce A units 3 and 4 were refurbished to return to power, and received their licence amendments for re-start on Apr 4 2003. Unit 4 attained its first post-refurbishment criticality on Aug 30, 2003, and was first re-synchronized to the grid on Oct 7 2003. Unit 3 attained its first post-refurbishment criticality on Dec 8, 2003, and was first re-synchronized to the grid on Jan 8 2004. These two units have together generated 50.2 million MWhe (gross), since restart up to April 30, 2009. Units 1 and 2 are being refurbished (including retubing the core and new steam generators), as announced by Bruce Power on Oct 17, 2005. Units 3 and 4 will be retubed and receive new steam generators after units 1 and 2 are restarted.

Bruce-5 has the top lifetime output for a CANDU reactor, attaining 154.9 million MWhe (gross) by April 30, 2009.

Calder Hall The world's first commercial electricity-producing nuclear power station (located in the UK).   It operated for 46+ years to Mar 31, 2003, when it closed for economic reasons.   It was a MAGNOX graphite-moderated natural-uranium-fuelled gas-cooled reactor.
CANDU CANada Deuterium Uranium pressurized heavy water reactor.   Developed and marketed by AECL.   It uses heavy water to cool the fuel and to moderate the neutrons to thermal energies.   The fuel is natural uranium in 0.5 m long fuel bundles.   Twelve or thirteen fuel bundles are located in each of 380 to 480 horizontal pressure tubes.   The reactor is refuelled while on-line (i.e. full power).   A total of 33 CANDUs have been built, of which 22 are operating, 8 are shut for overhaul, and three prototypes have been decommissioned.   A further three are under construction in South Korea (1) and China (2), and there are an additional 6 CANDU-copies in operation in India.

There are prospects for another three reactors to be ordered in the near future.   CANDU reactors are located (or being built) in seven countries - Canada, South Korea, India, China, Argentina, Pakistan and Romania.   The CANDU variants have been built in sizes of 22, 137, 220, 235, 540, 650, 680, 700, 715, 728, 904, 915 and 935 MWe (gross), some of which include steam production for industrial purposes.
CANFLEX fuel bundles and fuel evolution CANDU reactors are fuelled with natural uranium in pellets of UO2.    These pellets are placed in zirconium-alloy tubes to form fuel elements.    The elements are then joined together with end plates, to form a fuel bundle 0.5­m long.

The original CANDU fuel bundles used in NPD had either 7 or 19 fuel elements, of 2.5 and 1.5 cm outside diameters, respectively.   The bundles with larger pins were used in the outer (lower power) channels, since the heat generation was lower than the inner channels.   Larger fuel elements give better burnup (fuel utilization), but the elements run hotter because of a lower surface-to-volume ratio (the fuel is a ceramic which does not conduct heat as well as a metal).

The 19-element fuel bundles were also used in the second CANDU prototype - Douglas Point - which utilized 8.25 cm inside diameter pressure tubes like NPD.   When the larger Pickering reactors were built, it was decided to employ larger 10.3 cm inside diameter pressure tubes.   The fuel elements were similar to those in Douglas Point, but Pickering fuel used a total of 28 elements in each fuel bundle.

With the advent of the Bruce reactors and the CANDU 6 design, the fuel elements became smaller - 1.3 cm outside diameter.   This allowed the peak fuel element heat generation to increase without increasing the maximum fuel temperature.    Because of the smaller diameter elements, the number of elements increased to 37 per bundle, and the burnup decreased slightly.

The latest development in CANDU fuel is the CANFLEXTM bundle, which began testing in the Point Lepreau CANDU 6, in Sep 1998.   The 43 fuel elements in each CANFLEX bundle are of two sizes - 1.35 cm diameter inner elements, and 1.15 cm diameter outer elements.    The size difference is again to accommodate differential heat generation rates.   This time, however, the accommodation is within the bundle itself.    Since the outer elements partially shield the inner elements from thermal neutrons returning from the moderator, the outer elements run hotter than the inner elements.   By using smaller-diameter elements in these outer positions, therefore, the peak fuel element heat generation is lower in the CANFLEX bundles than in the 37-element bundles.

The CANFLEX bundles are just that - flexible.   They are designed to have a significantly higher critical channel power, which will help operating reactors maintain high performance as the reactors age.   The lower peak element heat generation increases the safety performance of the fuel, making it even safer than present CANDU fuel.   In the future it is planned to use the CANFLEX bundles as a carrier for advanced fuel types - perhaps depleted uranium, mixed oxides, or slightly enriched uranium.
Cernavoda Unit 1 is a CANDU-6 reactor - the first of five begun in Romania during the communist era.   The political and economic turmoil of the communist and immediate post-communist periods delayed construction.   The Unit 1 was completed in 1995, with pre-criticality testing taking place during that year.   The reactor attained first criticality on Apr 16 1996, and was declared commercial on Dec 2 1996.   It is the first western power reactor operating in what was known as eastern Europe.   Cernavoda-1 has significantly reduced the oil imports to Romania.
Unit 2 was completed in 2007 and was first connected to the grid on August 8, 2007.
Chornobyl This was the site of the world's worst nuclear accident, in Unit 4 of the four-unit RBMK reactor station at Chornobyl (Ukrainian spelling - also Tchernobyl or Chernobyl), 100 km north of Kiev, Ukraine.   The large (1000 MWe gross), vertical-channeled graphite-moderated reactor suffered from a power excursion during a pump run-down test at low power.   The reactor was not in a stable configuration at low power, and the power rapidly escalated when the cooling water flow dropped due to the pump run down.   The design of the shut off rods was inadequate, and increased the reactor reactivity as they were inserted.   The power increase caused a steam explosion that blew the reactor apart, including much of the surrounding building (Note that the explosion was steam - it is impossible for a reactor to have a nuclear explosion).   The graphite moderator caught fire, causing more of the fission product inventory to leave the reactor and be dispersed by the atmosphere.   Europe sustained various levels of contamination, and a 30-km radius exclusion zone (except for work) was established around the reactor.   Thirty-one people died within a few weeks, mainly from acute radiation sickness, and most of these were brave fire fighters sent to douse the burning chunks of graphite thrown out of the core.   There has been an increase in thyroid cancer in the region, due to iodine-131 (a significant fission product with an 8 day half-life) releases.   While thyroid cancer is usually successfully treated, there have been a few cancer deaths associated with Chornobyl.

Various factors are to blame for the accident and its consequences, including poor reactor design (instability at low power, no containment building), poor management (the test engineer was in charge of the reactor, not the chief reactor operator), lack of a safety culture, inadequate accident response, and bad communication (despite the onset of glasnost in the USSR).   The reactor was unlicenceable anywhere else but in the former Soviet Union.   The other RBMKs in the former USSR have been upgraded, but it is planned to shut them as soon as possible.   The last operating reactor (Unit 3) remained in operation until final shut down on Dec 15, 2000.   For in-depth coverage with many links, check the Virtual Nuclear Tourist
CNSC The Canadian Nuclear Safety Commission (CNSC), the renamed Atomic Energy Control Board, came into being on May 31, 2000, with the enactment of the Nuclear Safety and Control Act (NSCA).   See "AECB".
COSMOS-954 This was a Soviet satellite launched on Sep 18 1977.   It re-entered the Earth's atmosphere on Jan 24 1978, and disintegrated over the North West Territories.   Operation Morning Light was begun by the Canadian military to recover the remnants of the satellite, which had been powered by a small nuclear reactor.   Several thousand pieces of debris were recovered, which were analyzed at the Whiteshell Nuclear Research Establishment of AECL.
Other links on COSMOS-954 are:
CPD The Commercial Products Division of crown-owned Eldorado Mining and Refining was established to market radium, following WWII. It was absorbed into AECL on Aug 1 1952, and renamed the Radiochemical Company (of AECL) in Jul 1978. The CPD/RCC developed many new uses for radioisotopes, including Co-60 for cancer treatment and irradiators, and Mo-99 for medical diagnostics. The company was transferred from AECL on Sep 30, 1988 and renamed Nordion International Inc and Theratronics International Ltd as two new crown-owned corporations. MDS Inc. bought both crown corporations, and the company is now known as MDS Nordion. {I&I}
Critical A reactor is "critical" when it produces sufficient neutrons to maintain the fission power at its present level.   Super-critical means it is producing an excess of neutrons, and so the power is increasing.   Sub-critical means there are fewer neutrons being produced, so power is decreasing.   Prompt criticality occurs when a chain reaction is sustained on the prompt neutrons (i.e. neutrons that are released immediately upon the uranium atoms being split) alone, and causes a very rapid power increase.   There are also delayed neutrons, ones that are released somewhat later from the fission products.   Delayed neutrons (in the order of 1% of all neutrons in most reactors) have much longer mean lifetimes than prompt neutrons, and significantly slow the reactor response.   Thus delayed neutrons provide a means to control the chain reaction.   Reactors are kept critical only with delayed neutrons, although the SL-1 and Chornobyl reactor accidents apparently had some prompt criticality.
Darlington Four CANDU reactors located beside Lake Ontario, near Oshawa, Ontario.   The reactors first went critical from Nov 5 1989 to Mar 13 1993.   The reactors share a common vacuum building. Each of the Ontario Hydro reactors produces 935 MWe (gross).   These are the largest CANDUs, and are the basis for the single-unit CANDU-9 design.
Douglas Point This was the second Canadian pressurized heavy water reactor (PHWR) prototype, and the first officially designated "CANDU".   It was built by AECL and Ontario Hydro on the Bruce Peninsula on Lake Huron.   It produced 14,542,000 MWh of electricity (net) before being shut for economic reasons in May 1984.   The reactor power was 220 MWe (gross). More information can be found here
Embalse This reactor is a 648 MWe (gross) CANDU-6 design, built in Argentina.   It first went critical on Mar 13, 1983.
First criticality The date when the reactor first had a sustained fission reaction.   The reactor power is kept low for commissioning various systems and ensuring the reactor behaves as designed.   The power is incremented up over a few weeks, with additional tests at several power levels.
First electricity The date when the turbine-generator set first produces electricity when powered by the reactor.   Electricity is initially produced for test purposes, and only later is the power plant synchronized with the electrical grid.
First grid synchronization The date when the turbine-generator set is first connected to the electrical grid, thus providing electricity for use outside the power plant.   Synchronization refers to the generator output being correctly in-phase with the electrical grid, before the connection is made.   The frequency of a large grid (60 Hz in North America, 50 Hz in Europe) is almost perfectly constant, due to the large number of generators connected.
Gentilly-1 This was an experimental CANDU boiling light water power reactor located on the south shore of the St. Lawrence River in the Province of Québec, operated by AECL and Hydro Québec.   The 250 MWe (gross) reactor had 308 vertical-channels, was fuelled with natural uranium (UO2), and first attained criticality on Nov 12 1970.   It suffered from spatial control problems, due in part to a positive void coefficient.   It was planned to be converted to a plutonium-burning reactor, but this program was cut short by funding cuts, the success of the CANDU pressurized heavy water reactor (i.e Pickering), and the discovery of plentiful Canadian uranium deposits.   The reactor was last operated in 1977, and decommisioned in 1984.
Gentilly-2 This is a CANDU-6 reactor located on the south shore of the St. Lawrence River in the Province of Québec, operated by Hydro Québec.   The 675 MWe (gross) reactor first attained criticality on Sep 11 1982.
HANARO This research reactor was built in South Korea using AECL's MAPLE (Multipurpose Applied Physics Lattice Experiment) reactor technology.   First criticality was attained on Feb 8 1995 at 16:09.   At the ceremonies a wooden box containing two Chianti bottles was presented to KAERI (Korean Atomic Energy Research Institute) - Enrico Fermi and his colleagues had toasted the first criticality of CP-1 (1942) with Chianti in paper cups.   Bob Lidstone, manager of the Reactor Technology Branch of AECL which performed the design work, was invited to write a message on the box.   Echoing Fermi's words 52 years earlier, he wrote "The Italian navigator has just arrived in the Land of the Morning Calm.   The reception was friendly!   Congratulations and Best Wishes."
See HANARO web site.
Heavy Water Deuterium is a naturally-occuring hydrogen isotope (also known as heavy hydrogen), having a neutron in the atomic nucleus in addition to the proton present in normal (light) hydrogen.   Deuterium makes up 0.015% of all hydrogen atoms in the universe.   A heavy water molecule consists of two deuterium atoms and an oxygen atom.  Heavy water naturally occurs in minute quantities in everyday water, but complex processes must be used to concentrate it, since heavy water has essentially the same chemical properties as light water.   Deuterium is a good neutron moderator, and CANDU reactors use heavy water to moderate (slow down) neutrons to thermal energies.   Slow neutrons are much more likely to cause a uranium-235 atom to fission, which generates heat.
In service A reactor is declared in service when it has completed all its commissioning tests and meets all the regulator, vendor and buyer requirements for continuous operation.   The same as being declared "commercial".
India's Atomic Explosions On May 18, 1974, India detonated an "atomic device".   The bomb may have been made with plutonium recovered from fuel irradiated in CIRUS, the NRX-copy research reactor sold to India in 1955 under the Colombo Plan (A British Commonwealth initiative to help poorer nations).   CIRUS achieved first criticality on Jul 10 1960.   According to Canada Enters the Nuclear Age:
Cooperation on the technical aspects was good, but India was loath to accept Canadian inspection to ensure that plutonium was not diverted to non-peaceful uses.   There were no international standards to guide the discussion.   However, Canada received the right to inspect Canadian-supplied fuel and India gave assurances of peaceful uses only.
The breach of faith by the Indian government led to a cessation of nuclear technology transfer or trade from Canada to India, which remains in effect today except for safety-related matters.   India continued developing nuclear weapons, detonating additional bombs on May 11 and 13, 1998.
Kaiga Atomic Power Station Kaiga Atomic Power Station (Note - different from KAPS!), India.   Units 1 and 2 are upgraded (235 MWe) copies of the RAPS reactors.   First criticality of Unit 2 was Sep 24 1999, commercial operation Dec 22 1999.   First criticality of Unit 1 was Sep 26 2000.   Unit 1 suffered a containment building partial collapse during construction in 1994.   One feature which distinguishes the Kaiga nuclear reactors from other Indian PHWRs is a full double reactor containment.   The inner dome is made of pre-stressed concrete, and the outer one of re-inforced concrete.    Also, one of the diesel generators of each unit is located inside the containment of the other reactor.
KAPS Kakrapar Atomic Power Station, India.   Units 1 and 2 are upgraded (235 MWe) copies of the RAPS reactors.   First criticalities were Sep 3 1992 and Jan 8 1995.
KANUPP Karachi Nuclear Power Plant, Pakistan.   Uprated (137 MWe) version of NPD, designed and built by Canadian General Electric.   First criticality Aug 1, 1971.   First electricity Oct 1971. Shut for life extension assessment in Dec 2002, restarted in Nov 2003.
W.B. Lewis Wilfrid Bennett Lewis (1908 - 1987) was a physicist who directed AECL's nuclear research program from 1946 to 1973.   He was born at Castle Carrock, England, and studied and worked at Cavendish Laboratories in Cambridge, England, under Lord Ernest Rutherford and Sir John Cockcroft.   In 1946 he joined the National Research Council's atomic-energy project at Chalk River, and in 1963 he became senior vice-president of Atomic Energy of Canada Ltd. - a position he held until he retired in 1973.   He was also on faculty of Queen's University in Kingston, Ontario.   He is considered the father of the CANDU reactor.

From Nuclear Pursuits: the scientific biography of Wilfrid Bennett Lewis (Ruth Fawcett, McGill-Queen's University Press, 1994):

Lewis's drive, intelligence, and remarkable organizational skills placed him at the forefront of Canada's nuclear program.   Convinced that nuclear energy could be used economically for generating electricity, Lewis fostered a collaboration between AECL and Ontario Hydro that led to the development of the CANDU reactor.   Lewis's efforts in developing this design, and his effective support of a strong tradition of basic research, are his most important legacies.
MAPLE Multipurpose Applied Physics Lattice Experiment.   This is a new research-reactor technology developed by AECL, capable of fuels and materials testing, isotope production, and neutron experimentation.   The MAPLE concept features an H2O-cooled and D2O-reflected core, and operates with a thermal power of 5 to 40 MW(th).   It offers a high thermal neutron flux, small core volume, and accommodation for multiple beam-tubes and in-core experimental sites, as well as driven spectrum-specific facilities in the reflector (cold-neutron source, fast-neutron flux trap, etc.).

One reactor based on MAPLE technology is in operation (see the HANARO listing above).    Two MAPLE reactors were constructed for isotope production at AECL's Chalk River laboratories, for MDS Nordion, a radiopharmaceutical supplier.   These 10 MW(th) reactors were intended to replace the isotope-production capability of AECL's NRU reactor.   For a variety of reasons (technical, financial, managerial, political, regulatory), the MAPLE Medical Isotope Reactor (MMIR) project was abandoned on May 16, 2008.   NRU remains in operation as both a research reactor and supplier of medical radioisotopes.

MAPS Madras Atomic Power Station, India.   Units 1 and 2 were upgraded (235 MWe) copies of the RAPS reactors, but were derated to 170 MWe each.   First criticalities were Jul 2 1983 and Aug 12 1985.
McMaster University Reactor The McMaster nuclear reactor (Hamilton, Ontario) is the largest Canadian research reactor outside of AECL.   It is a 2 MW (thermal) swimming-pool reactor of American design, first opened in 1959.   The reactor was upgraded to 5 MW for early work (1972) on the development of molybdenum-99 production, from which the medical imaging isotope technetium-99m is obtained.   The reactor website has an extensive history and photo archive section.
NAPS Narora Atomic Power Station, India.   Units 1 and 2 are upgraded (235 MWe) copies of the RAPS reactors.   First criticalities were Mar 12 1989 and Oct 24 1991.
USS Nautilus The first nuclear-powered vessel in the world.   It used the first (other than a prototype) pressurized water reactor (PWR) in the world.   This reactor design, in larger and modified versions, provides most of the world's nuclear-generated electricity.
Nuclear Fission Nuclear fission occurs when a neutron enters the nucleus (core) of an atom, and splits the nucleus into two or more lighter nuclei.   There is a large amount of energy released when a very heavy nucleus (e.g. uranium or plutonium) splits, and this energy turns into heat (another form of energy).   If the heat is transferred to a "working fluid" (e.g. water, helium, CO2), the heat can be used to spin a turbine-generator set (to produce electricity) or to heat a building.  

Fissions also produce more neutrons, which are necessary to maintain the chain reaction (continual nuclear fissions in unfissioned nuclei).   Some neutrons can be "tapped off" in a reactor to bombard materials to study the inner workings of the materials or to provide an image of the material (similar to an X-ray, but for denser materials).   Neutrons can also be used to produce new materials (e.g. technetium-99 and cobalt-60) for medical imaging and cancer treatment.

Chemists Otto Hahn and Fritz Strassmann, bombarded various elements with neutrons (from naturallly occurring radioisotopes).   This work was done at the Kaiser Wilhelm Institute (Berlin) in the period 1935 to 1939.   When it came to bombarding uranium, however, the results were perplexing - lighter elements (including barium and krypton) were observed after the neutron bombardment.   Irene Curie, daughter of Nobel prize winner Marie Curie, and Pavel Savitch helped determine the post-bombardment uranium chemistry in their Paris laboratory.   Physicist Lise Meitner (a former colleague of Hahn who had to flee Austria after Hitler's annexation of Austria in Mar 1938) devised the theory of nuclear fission, and experimental proof was obtained by her nephew Otto Frisch in Jan 1939, at the Niels Bohr Institute in Copenhagen.  

Meitner and Frisch proposed the name 'nuclear fission', published the first theoretical explanation of the process and predicted the enormous energy released.

Lise Meitner and the Discovery of Nuclear Fission
by Ruth Lewin Sime, Scientific American, Jan 1998 

NPD Nuclear Power Demonstration reactor.   This was the prototype CANDU reactor, and the first power reactor in Canada.   It was located upstream of AECL's Chalk River laboratories, along the Ottawa River's south shore (i.e. in Ontario).   The reactor had a maximum continuous output of 22 MWe gross (19.5 MWe net).   It first attained criticality on Apr 11 1962, and produced Canada's first nuclear-generated electricity on Jun 4 1962.   Full power was first achieved on Jun 28 1962.

The reactor was built as a joint AECL/Ontario Hydro/Canadian General Electric project, and was initially intended to use a vertically-fuelled pressure vessel reactor.   The design was changed in 1957 to natural uranium fuel bundles in horizontal pressure tubes in unpressurized heavy water moderator, with on-line refuelling.   These are hallmarks of the CANDU reactor.   The reactor had 132 fuel channels (each fuel channel comprised a pressure tube inside a calandria tube) and the coolant leaving the channels was 7.2 MPa and 277oC.   The main reactivity control was by adjusting the heavy-water moderator level, which could be rapidly dumped for fast shut down.   NPD was finally shut down on May 5 1987, for economic reasons, having delivered 3,019,000 MWhe to the Ontario Hydro grid.   Canadian General Electric built an enlarged (137 MWe) and improved version of NPD in Pakistan (KANUPP).

An interesting article on NPD, in the Fall 1965 edition of Nuclear Safety can be down loaded in pdf format (745 kB):   Scroll down to the article titled "NPD reactor operating experience", under the section "Current Events", and click on the author "G. Hake".

In addition, an article Nuclear Power Demonstration Reactor, from the Oct 1962 edition of Nuclear Engineering, has been reproduced with the permission of Nuclear Engineering International.   There is also a reprint of an IAEA brochure on NPD AECL-1330, and an AECL brochure en français.
NRU Nuclear Research Universal, was the second high-power (200 MW thermal) Canadian research reactor, built at the Chalk River Laboratories of AECL.   The reactor attained first criticality on Nov 3 1957, and remains in operation (2009) as both a research tool and a producer of medical radioisotopes.
NRX Nuclear Research eXperimental, the first high-power (40 MW thermal) Canadian research reactor, built at the Chalk River Laboratories of AECL.   The reactor attained first criticality on Jul 22 1947, and remained in operation until Jan 29 1992 (decision to decommission made Apr 8, 1993).   It suffered from an accident on Dec 12 1952, but was rebuilt.
Oklo Reactors These were the first (known) reactors in the world, operating some 1.8 billion years ago.   They were discovered in 1972, and have been extensively studied.   One of the outcomes of these natural reactors is that the fission products did not disperse, but stayed very close to where they were formed.   The reactor provides a natural analogue for fission product transport from proposed deep geological repositories for used nuclear fuel.   Check Fossil Reactors.
Pickering Eight CANDU reactors located to the east of Toronto, Ontario.   Each of the Ontario Hydro reactors produces 540 MWe (gross).   Two sets of four reactors were built - Pickering A (first criticalities from Feb 25 1971 to May 16 1973) and Pickering B (first criticalities from Oct 23 1982 to Dec 17 1985).   Pickering reactors were the first large-scale CANDUs.   The reactors share a common vacuum building.

Pickering A units were shut down for extensive upgrades and refurbishments. Unit 4 was the first to restart, re-synchronized on Aug 22 2003 and declared commercial on Sept 25 2003.
Here are the shut down dates with total net electricity production (to Aug 22, 2003) since the units were declared commercial (each reactor also delivered electricity to the grid prior to being declared commercial):

Pickering-122:55Dec 28 199774,586,000 MWhe
Pickering-222:20Dec 29 199770,293,000 MWhe
Pickering-323:48Dec 27 199779,287,000 MWhe
Pickering-421:43Apr 2 199673,287,000 MWhe
Point Lepreau This is a CANDU-6 reactor located on the shores of the Bay of Fundy in New Brunswick, operated by New Brunswick Power.    The 680 MWe (gross) reactor first attained criticality on Jul 25 1982, generated its first MWhe on Sept 11 1982 and generated its 100 millionth MWhe (gross) on Mar 8, 2003.
Prompt Critical There are essentially two main groups of neutrons produced by the fission process.   Prompt neutrons are produced immediately (i.e. promptly) upon a fission occurring, and delay neutrons are produced by fission products which decay by expelling a neutron.   The delay neutrons in a CANDU represent only about 0.6% of all neutrons, but are very important in controlling the reactor.   If a reactor can maintain its fission power on the prompt neutrons alone, it is prompt critical and can overpower very quickly (depending on the control system).
Qinshan Qinshan-4 and -5 are two CANDU-6 reactors (each 728 MWe gross) designed and built by AECL at the Qinshan site in China, 125 km southwest of Shanghai.   They are the third set of power reactors at Qinshan, the others being domestically-designed PWRs: Qinshan-1 is 300 MWe (operational 1991), and Qinshan-2 and -3 are 600 MWe each.   Qinshan-4 first went critical on Sep 20 2002 at 22:08, and was declared in commercial operation on Dec 31, 2002, 38 days ahead of schedule.   Qinshan-5 first went critical on Apr 29 2003 at 23:58, 52 days ahead of schedule.   It was declared in commercial operation at 00:18 on Jul 24 2003, 16 weeks ahead of schedule.   The project was on budget.
RAPS Rajasthan Atomic Power Station, India.   Unit 1, based on the AECL/Ontario Hydro Douglas Point reactor (220 MWe), was built by AECL and attained first criticality on Aug 11, 1972.   Further nuclear technology transfer to India was halted in 1974, after India detonated a "peaceful" nuclear device.   Unit 2 was completed by India and first criticality was Oct 8, 1980.   Unit 1 was shut for refurbishment assessment on Apr 30, 2002, having generated 11,329,000 MWhe (gross), and was re-started in Feb 2004.

Both units also generated steam for industrial use.   Unit 1 was down-rated to 100 MWe.   Unit 2 was retubed and returned to service in 1998.

Unit 3, essentially a copy of Units 1 and 2 but with double containment and other enhancements, attained first criticality Dec 25, 1999, and was first connected to the grid on Mar 10, 2000.   Unit 4 (similar to Unit 3) attained first criticality on Nov 3, 2000.    To Mar 31, 2002, the four RAPS units had generated a total of 36.4 million MWhe (gross) in commercial operation.
SL-1 This American military BWR was designed to produce 260 kW of electricity plus 400 kW of heat for remote locations.   At 21:01 on Jan 3 1961, the reactor suffered a prompt critical excursion as a control rod was moved (it is believed) beyond the allowed position.   The three operators were killed by the accident, having suffered high levels of neutron irradiation.
SLOWPOKE-2 The 5 kW (thermal) SLOWPOKE-1 (Safe LOW POwer Critical(K) Experiment) research reactor was developed by AECL at Chalk River, and first went critical in May 1970 (See SLOWPOKE history).   The reactor was dismantled and rebuilt at the Environmental Science and Engineering Institute of the University of Toronto.   It was later uprated to a SLOWPOKE-2 design (20 kW thermal), and was shut due to budget cuts in 1998.   Other SLOWPOKE-2 reactors were installed at the University of Alberta (Edmonton), Saskatchewan Research Council (Saskatoon), Royal Military College (Kingston), MDS Nordion (Kanata) (now shut), Dalhousie University (Halifax) , L'Ecole Polytechnique (Montréal) , and the Centre for Nuclear Sciences, Kingston (Jamaica).   The reactor consists of a core in the bottom of an unpressurized pool of water.   The SLOWPOKE Energy System was a later design intended for central heating systems.   The SLOWPOKE Demonstration Reactor (SDR) was built at AECL's Whiteshell Laboratories in the 1980's and was run in tests up to half of its design output of 2 MW (thermal).   The reactor has been defuelled and is being decommissioned.
Three Mile Island-2 Two 871 MWe (gross) pressurized water reactors were built near Harrisburg, Pennsylvania.   The second unit, having only operated four months, suffered a loss-of-coolant accident (LOCA) and partial fuel melt when a valve did not close as expected.   No one was hurt in the accident, and a small amount of radiation was released.   The fuel has since been removed from the reactor vessel.   Details of the accident can be found here.

While very expensive, the accident was very valuable with respect to western reactor safety; the accident and subsequent analyses improved reactor design, operating practices, and safety analysis techniques.

Tokaimura A criticality accident occurred in the conversion test building of the Japanese Nuclear Fuel Conversion Company (JCO) on Sep 30 1999.   The small fuel fabrication plant is in the village of Tokai in the Ibaraki prefecture, 140 km northeast of Tokyo.   Criticality occurred in a precipitation tank when workers added excessive amounts of enriched (18.8% U-235) uranyl nitrate, in violation of procedure.   Flash criticality occurred at 10:35, and criticality continued intermittently for about 17 hours.   The intermittent reaction was halted when cooling water surrounding the tank was drained - the water had acted as a neutron moderator and reflector.   Off-site consequences included the evacuation of people living within 350 m of the plant, and an additional 300,000 people living within 10 km of the plant were urged to stay in doors as a precautionary measure.    There was little radiation released in the form of fission products, but the reaction itself caused neutron and gamma radiation that emanated from the tank.

The three workers received high doses, inducing acute radiation damage.   Hisachi Ouchi (35) died Dec 21, 1999, and Masato Shinohara (40) died on Apr 27, 2000, both following multiple organ failure.

Investigation has shown that the company violated normal safety standards and legal requirements, and ignored both the official procedures manual and its own unauthorised procedures!   The plant workers were apparently poorly trained and did not even know the meaning of criticality.   The accident was evidently the result of gross negligence.   A full investigation is underway, by both the Japanese authorities and the International Atomic Energy Agency of the United Nations.   A more detailed (and up-to-date) description of the accident is found at the Uranium Information Centre.
Windscale-1 A graphite-moderated, air-cooled (no containment) plutonium-production (for weapons) reactor built in the UK.   It caught fire on Oct 10 1957, due to the Wigner effect (energy release upon heating to stress relieve the graphite).   There was a significant release of radionuclides.   See Virtual Nuclear Tourist
Wolsong Four CANDU-6 reactors (Unit 1 = 678 MWe gross, Units 2-4=715 MWe each, gross) are at this site in South Korea.   They are operated by the Korean Electric Power Company KEPCO.   Unit 1 first went critical on Nov 21 1982, Unit 2 on Jan 27 1997, Unit 3 on Feb 20 1998, and Unit 4 on Apr 10 1999.   Wolsong-1 was the first CANDU-6 to attain a lifetime generation of 100 million MWhe, gross, in Nov 2002.
WR-1 A large organic-cooled, heavy-water moderated research reactor built at the Whiteshell Nuclear Research Establishment (now Whiteshell Laboratories) of AECL, located 100 km east-northeast of Winnipeg, Manitoba.   See An History of the WR-1 Reactor at Whiteshell Laboratories, Manitoba.   Aussi disponible en français.
ZEEP The Zero Energy Experimental Pile was the first Canadian reactor, and the reactor operational outside the USA.   It was a low-power heavy-water moderated uranium-metal-fuelled pool reactor, where the primary reactivity control was via the moderator level.   The initial power level was only 1 W, but was later increased to 250 W (thermal).   It first attained criticality on Sep 5 1945, and was finally shut and retired on Jul 27 1970.

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