Chalk River: The Development of Canada s Nuclear Research Facilities

2. Canada�s involvement in the growing nuclear research effort also resulted from the conflict in Europe between the Allies and Nazi Germany. In September of 1942, British and Canadian governments established a joint British-Canadian laboratory in Montreal, Quebec under the auspices of the National Research Council of Canada. Scientists such as England�s John Cockcroft and French Physicists Lew Kowarski and Hans von Halban relocated to the safety of Canada where they worked together with Canadian researchers on the design and development of a heavy water moderated nuclear reactor for the production of plutonium, a prime fissile ingredient for the American�s atomic bombs.Canada�s involvement in the growing nuclear research effort also resulted from the conflict in Europe between the Allies and Nazi Germany. In September of 1942, British and Canadian governments established a joint British-Canadian laboratory in Montreal, Quebec under the auspices of the National Research Council of Canada. Scientists such as England�s John Cockcroft and French Physicists Lew Kowarski and Hans von Halban relocated to the safety of Canada where they worked together with Canadian researchers on the design and development of a heavy water moderated nuclear reactor for the production of plutonium, a prime fissile ingredient for the American�s atomic bombs.

3. In 1944 the project team moved to specially constructed laboratories at Chalk River, Ontario, 200 kilometres northwest of Ottawa on the Ottawa River near the border of Quebec. As Canada�s national nuclear laboratory, Chalk River has grown over the past 60 years to currently employ over 2000 people. The sections that follow outline some of the major historical achievements of the Chalk River Laboratories.In 1944 the project team moved to specially constructed laboratories at Chalk River, Ontario, 200 kilometres northwest of Ottawa on the Ottawa River near the border of Quebec. As Canada�s national nuclear laboratory, Chalk River has grown over the past 60 years to currently employ over 2000 people. The sections that follow outline some of the major historical achievements of the Chalk River Laboratories.

4. In the Fall of 1945, a small low-power (1 watt) prototype reactor named ZEEP (Zero Energy Experimental Pile) was developed at the National Research Council of Canada�s newly constructed Chalk River Laboratories in Ontario to help the Canadian researchers better understand the physics and material problems of heavy water moderated nuclear reactions.� This marked a major milestone in Canada�s participation in nuclear research, becoming only the second country in the world, besides the United States, to use a reactor to control the nuclear fission process.In the Fall of 1945, a small low-power (1 watt) prototype reactor named ZEEP (Zero Energy Experimental Pile) was developed at the National Research Council of Canada�s newly constructed Chalk River Laboratories in Ontario to help the Canadian researchers better understand the physics and material problems of heavy water moderated nuclear reactions.� This marked a major milestone in Canada�s participation in nuclear research, becoming only the second country in the world, besides the United States, to use a reactor to control the nuclear fission process.

5. The ZEEP reactor was built primarily as a simplified prototype for the larger, more complex NRX (National Research Experimental) reactor that the NRC was planning to build at the Chalk River site. In later years, ZEEP was used for important research on the behaviour of neutrons in reactors and to provide data for the design of other reactors.The ZEEP reactor was built primarily as a simplified prototype for the larger, more complex NRX (National Research Experimental) reactor that the NRC was planning to build at the Chalk River site. In later years, ZEEP was used for important research on the behaviour of neutrons in reactors and to provide data for the design of other reactors.

6. Following the Second World War, Canada continued its support of the British and US weapons programs as a member of the NATO alliance, and continued its efforts to develop a powerful nuclear research reactor.� In 1947 this became a reality when the 20 megawatt NRX (National Research Experimental) reactor came online at the Chalk River facility.� NRX was for a time the world's most powerful research reactor, vaulting Canada into the forefront of physics research.Following the Second World War, Canada continued its support of the British and US weapons programs as a member of the NATO alliance, and continued its efforts to develop a powerful nuclear research reactor.� In 1947 this became a reality when the 20 megawatt NRX (National Research Experimental) reactor came online at the Chalk River facility.� NRX was for a time the world's most powerful research reactor, vaulting Canada into the forefront of physics research.

7. On December 12, 1952, the NRX reactor suffered a partial meltdown due to operator error and mechanical problems in the shut-off systems. Some fuel cladding burst, and as a result there was a release of radioactive material, mostly contained within the NRX building. Clean-up of the site required several months with the reactor core being removed and buried.On December 12, 1952, the NRX reactor suffered a partial meltdown due to operator error and mechanical problems in the shut-off systems. Some fuel cladding burst, and as a result there was a release of radioactive material, mostly contained within the NRX building. Clean-up of the site required several months with the reactor core being removed and buried.

8. A new core put in its place and the refurbished reactor was operating again, at a higher power level (ultimately 42 megawatts), within two years. �The lessons learned in the 1952 accident advanced the field of reactor safety significantly,and the concepts it highlighted (diversity and independence of safety systems, guaranteed shutdown capability, efficiency of man-machine interface) became fundamentals of reactor design.� While NRX was initially designed with the production of weapons-grade plutonium for the US military as one of its functions, by the 1960s the Canadian government had decided to focus on nuclear non-military research and the production of medical isotopes such as iodine-131, phosphorus-32, carbon-14, and cobalt-60.� After 45 years of esteemed service, NRX was taken offline in 1992. A new core put in its place and the refurbished reactor was operating again, at a higher power level (ultimately 42 megawatts), within two years. �The lessons learned in the 1952 accident advanced the field of reactor safety significantly,and the concepts it highlighted (diversity and independence of safety systems, guaranteed shutdown capability, efficiency of man-machine interface) became fundamentals of reactor design.� While NRX was initially designed with the production of weapons-grade plutonium for the US military as one of its functions, by the 1960s the Canadian government had decided to focus on nuclear non-military research and the production of medical isotopes such as iodine-131, phosphorus-32, carbon-14, and cobalt-60.� After 45 years of esteemed service, NRX was taken offline in 1992.

9. The NRU (National Research Universal) reactor design was started in 1949, with plans for it to be built as the successor to the NRX reactor at the Chalk River Laboratories. At the time that NRX was built, it was not known how long a research reactor could be expected to operate so the management of Chalk River Laboratories began planning the NRU reactor to ensure continuity of the research programs. NRU started self-sustained operation on November 3, 1957, a decade after NRX, and was much more powerful. It was initially designed as a 200 MW reactor, fuelled with natural uranium however in 1964 it was converted to 60 MW with high-enriched uranium (HEU) fuel and then converted a third time in 1991 to 135 MW running on low-enriched uranium (LEU) fuel. The NRU (National Research Universal) reactor design was started in 1949, with plans for it to be built as the successor to the NRX reactor at the Chalk River Laboratories. At the time that NRX was built, it was not known how long a research reactor could be expected to operate so the management of Chalk River Laboratories began planning the NRU reactor to ensure continuity of the research programs. NRU started self-sustained operation on November 3, 1957, a decade after NRX, and was much more powerful. It was initially designed as a 200 MW reactor, fuelled with natural uranium however in 1964 it was converted to 60 MW with high-enriched uranium (HEU) fuel and then converted a third time in 1991 to 135 MW running on low-enriched uranium (LEU) fuel.

10. On 24 May 1958, less than a year after it began operation, the NRU suffered a substantial accident. A damaged uranium fuel rod caught fire and was torn in two as it was being removed from the core. The fire was extinguished, but a sizeable quantity of radioactive combustion products had contaminated the interior of the reactor building and, to a lesser degree, an area of the surrounding laboratory site. The clean-up and repair took only three months so NRU was operating again in August 1958. Care was taken to ensure no one was exposed to dangerous levels of radiation and staff involved in clean-up were monitored over the following decades. No health effects were observed.On 24 May 1958, less than a year after it began operation, the NRU suffered a substantial accident. A damaged uranium fuel rod caught fire and was torn in two as it was being removed from the core. The fire was extinguished, but a sizeable quantity of radioactive combustion products had contaminated the interior of the reactor building and, to a lesser degree, an area of the surrounding laboratory site. The clean-up and repair took only three months so NRU was operating again in August 1958. Care was taken to ensure no one was exposed to dangerous levels of radiation and staff involved in clean-up were monitored over the following decades. No health effects were observed.

11. One of the major advantages of NRU's design is that it can be taken apart fairly easily and quickly to allow for replacements of major parts For example, since the reactor�s calandria, the vessel which contains its nuclear reactions, is made of aluminum, it has required replacement because of corrosion.� Another design advantage of the NRU is its ability for on-power refueling, meaning that used fuel can be removed and new fuel can be inserted without shutting down the reactor.� Both of these innovations � core refurbishment and on-power refueling � eventually found their way into the Canadian CANDU power reactor design. During the course of its operation, NRU has been responsible for the production of a majority of the world�s supply of medical isotopes which are used in the treatment and diagnosis of over 20 million people worldwide each year.� Additionally, NRU is the source of the fundamental knowledge that was required to develop Canada's fleet of nuclear power stations. Fuel and structural material needed to build a CANDU reactor are tested and proved in NRU. Domestic nuclear power generation prevents millions of tonnes of greenhouse gas emissions each year, by reducing Canada's use of fossil fuels, and is a $6.6 billion industry. In June 2007, a new neutron scattering instrument was opened in NRU. The D3 Neutron Reflectometer is designed for examining surfaces, thin films and interfaces. The technique of Neutron Reflectometry is relatively new, and capable of providing unique information on materials in the nanometer length scale.� Based on its impressive record in the medical isotope, neutron scattering, and nuclear power research fields, NRU is considered by many to be the most ambitious and productive science research facility in Canada. One of the major advantages of NRU's design is that it can be taken apart fairly easily and quickly to allow for replacements of major parts For example, since the reactor�s calandria, the vessel which contains its nuclear reactions, is made of aluminum, it has required replacement because of corrosion.� Another design advantage of the NRU is its ability for on-power refueling, meaning that used fuel can be removed and new fuel can be inserted without shutting down the reactor.� Both of these innovations � core refurbishment and on-power refueling � eventually found their way into the Canadian CANDU power reactor design. During the course of its operation, NRU has been responsible for the production of a majority of the world�s supply of medical isotopes which are used in the treatment and diagnosis of over 20 million people worldwide each year.� Additionally, NRU is the source of the fundamental knowledge that was required to develop Canada's fleet of nuclear power stations. Fuel and structural material needed to build a CANDU reactor are tested and proved in NRU. Domestic nuclear power generation prevents millions of tonnes of greenhouse gas emissions each year, by reducing Canada's use of fossil fuels, and is a $6.6 billion industry. In June 2007, a new neutron scattering instrument was opened in NRU. The D3 Neutron Reflectometer is designed for examining surfaces, thin films and interfaces. The technique of Neutron Reflectometry is relatively new, and capable of providing unique information on materials in the nanometer length scale.� Based on its impressive record in the medical isotope, neutron scattering, and nuclear power research fields, NRU is considered by many to be the most ambitious and productive science research facility in Canada.

12. The SLOWPOKE (acronym for Safe Low-Power Kritical Experiment) is a low-energy, pool-type nuclear research reactor designed by Atomic Energy of Canada Limited (AECL) in 1967 at Whiteshell Laboratories in Pinawa, northeast of Winnipeg, Manitoba.� This type of reactor was primarily intended for Canadian universities, providing a higher neutron flux than available from small commercial accelerators, while avoiding the complexity and high operating costs of existing nuclear reactors.� In 1970 a prototype unit known as SLOWPOKE-1 was designed and built at Chalk River and the next year was moved to the University of Toronto.�The SLOWPOKE (acronym for Safe Low-Power Kritical Experiment) is a low-energy, pool-type nuclear research reactor designed by Atomic Energy of Canada Limited (AECL) in 1967 at Whiteshell Laboratories in Pinawa, northeast of Winnipeg, Manitoba.� This type of reactor was primarily intended for Canadian universities, providing a higher neutron flux than available from small commercial accelerators, while avoiding the complexity and high operating costs of existing nuclear reactors.� In 1970 a prototype unit known as SLOWPOKE-1 was designed and built at Chalk River and the next year was moved to the University of Toronto.�

13. It had only one sample site in its design and initially operated at a power level of 5 kW with a permissible period of unattended operation of 4 hours.� In 1973 the power was increased to 20 kW and the period of unattended operation increased to 18 hours. The first commercial version of the SLOWPOKE reactor was started up in 1971 at AECL's Commercial Products Division in Ottawa; and in 1976 a commercial design, named SLOWPOKE-2, was installed at the University of Toronto, replacing the original SLOWPOKE-1 unit. The commercial model has five sample sites in the beryllium reflector and five sites stationed outside the reflector. Between 1976 and 1984, seven SLOWPOKE-2 reactors with Highly Enriched Uranium (HEU) fuel were commissioned in six Canadian cities and in Kingston, Jamaica. In 1985 the first Low-Enriched Uranium (LEU) fuelled SLOWPOKE-2 reactor was commissioned at the Royal Military College of Canada (RMC) in Kingston, Ontario. Since then several units have been converted to LEU. In the early 1980�s AECL also designed and built a scaled-up version (2-10 MW) called SLOWPOKE-3 for district heating at its Whiteshell Nuclear Research Establishment in Manitoba. The economics of a district-heating system based on SLOWPOKE-3 technology were initially estimated to be competitive with that of conventional fossil fuels for use in remote communities, however market interest in the SLOWPOKE heating system eventually dwindled due to the low price of natural gas.� Currently, the high price of oil and natural gas has sparked renewed interest in the use of nuclear energy for district heating purposes. It had only one sample site in its design and initially operated at a power level of 5 kW with a permissible period of unattended operation of 4 hours.� In 1973 the power was increased to 20 kW and the period of unattended operation increased to 18 hours. The first commercial version of the SLOWPOKE reactor was started up in 1971 at AECL's Commercial Products Division in Ottawa; and in 1976 a commercial design, named SLOWPOKE-2, was installed at the University of Toronto, replacing the original SLOWPOKE-1 unit. The commercial model has five sample sites in the beryllium reflector and five sites stationed outside the reflector. Between 1976 and 1984, seven SLOWPOKE-2 reactors with Highly Enriched Uranium (HEU) fuel were commissioned in six Canadian cities and in Kingston, Jamaica. In 1985 the first Low-Enriched Uranium (LEU) fuelled SLOWPOKE-2 reactor was commissioned at the Royal Military College of Canada (RMC) in Kingston, Ontario. Since then several units have been converted to LEU. In the early 1980�s AECL also designed and built a scaled-up version (2-10 MW) called SLOWPOKE-3 for district heating at its Whiteshell Nuclear Research Establishment in Manitoba. The economics of a district-heating system based on SLOWPOKE-3 technology were initially estimated to be competitive with that of conventional fossil fuels for use in remote communities, however market interest in the SLOWPOKE heating system eventually dwindled due to the low price of natural gas.� Currently, the high price of oil and natural gas has sparked renewed interest in the use of nuclear energy for district heating purposes.

14. MAPLE (Multipurpose Applied Physics Lattice Experiment) is the name of AECL�s now cancelled pool-type research-reactor design, capable of fuels and materials testing and neutron experimentation, and medical isotope production.� In 1986, AECL commissioned the construction of two 10 MW MAPLE reactors at Chalk River Laboratories. AECL would own and operate the two reactors on behalf of MDS Nordion, a global radiopharmaceutical supplier based in Ottawa, Ontario. MMIR-1 (or "MAPLE 1"), the first of these two new MAPLE medical isotope production reactors, was declared "critical" (began a self-sustaining chain reaction) at 2:53 a.m. on Saturday, February 19, 2000 at Chalk River Laboratories, becoming the world's first reactor of the new millenium.� MMIR-2 ("MAPLE 2") achieved first criticality at 2:08 p.m. on October 9, 2003. While commissioning exercises successfully took the MMIR-2 core to high power (8 MW) and tested many of the crucial safety systems, several first-of-a-kind technical issues delayed the commissioning process, to the point where AECL and the Government of Canada decided, in May 2008, to discontinue the project.� The reasons cited were the costs of the project and the time frame and risks of continuing with the project.� As of July, 2008, MDS, the parent company of MDS Nordion, who had contracted with AECL for the design, had launched proceedings against AECL, including a $1.6 billion dollar compensation claim.� This legal process is underway as of the winter of 2008. MAPLE (Multipurpose Applied Physics Lattice Experiment) is the name of AECL�s now cancelled pool-type research-reactor design, capable of fuels and materials testing and neutron experimentation, and medical isotope production.� In 1986, AECL commissioned the construction of two 10 MW MAPLE reactors at Chalk River Laboratories. AECL would own and operate the two reactors on behalf of MDS Nordion, a global radiopharmaceutical supplier based in Ottawa, Ontario. MMIR-1 (or "MAPLE 1"), the first of these two new MAPLE medical isotope production reactors, was declared "critical" (began a self-sustaining chain reaction) at 2:53 a.m. on Saturday, February 19, 2000 at Chalk River Laboratories, becoming the world's first reactor of the new millenium.� MMIR-2 ("MAPLE 2") achieved first criticality at 2:08 p.m. on October 9, 2003. While commissioning exercises successfully took the MMIR-2 core to high power (8 MW) and tested many of the crucial safety systems, several first-of-a-kind technical issues delayed the commissioning process, to the point where AECL and the Government of Canada decided, in May 2008, to discontinue the project.� The reasons cited were the costs of the project and the time frame and risks of continuing with the project.� As of July, 2008, MDS, the parent company of MDS Nordion, who had contracted with AECL for the design, had launched proceedings against AECL, including a $1.6 billion dollar compensation claim.� This legal process is underway as of the winter of 2008.