947:
133:-moderated design, coupled with the high neutron flux of the reactor, made it relatively inexpensive for AECL to produce medical-grade cobalt-60. For example, the cost of the entire unit used to perform the first cobalt-60 treatment was about $ 50,000. By way of contrast, it would cost $ 50,000,000 just to produce enough
203:(PCR), which was in disagreement with the prediction of the modelling, and was a significant barrier to commissioning. A positive power co-efficient means that the reactor becomes more reactive when it heats up; in the case of an unplanned power spike, such a design can "run away" and potentially cause a
191:
Originally planned to complete construction in 1999 and 2000, both reactors were instead completed in May 2000. An operational license was granted in August 1999 for the MAPLE I reactor, and extended to include the MAPLE II reactor in June 2000. Commissioning testing was begun immediately, with the
167:
As part of a restructuring taking place around the same time, the medical isotopes side of AECL was reorganized as
Nordion in 1988. Work on the X10 project essentially ended at this point. Nordion company was purchased by MDS in 1991, and an agreement was reached between AECL and MDS Nordion that a
195:
However, during testing, it was noted that some of the emergency shut-off rods in the MAPLE I reactor could fail to deploy in certain demanding situations. This failure was ascribed to workmanship and design issues, and related to fine metal particles accumulating in the control rods' housing and
222:
On 16 May 2008, AECL released a statement announcing that the MAPLE program had been terminated, as it had become "no longer feasible to complete the commissioning and start-up of the reactors". In this statement, AECL indicated that they would move to further extend the licence of the operating
210:
Consequently, significant efforts were made to resolve the outstanding issues, but progress towards commissioning the reactors was markedly slowed. During the subsequent eight-year-long delay in the start of commercial production, the project significantly overran its budgeted cost. The original
171:
The design that resulted involved a facility with two identical reactors, each capable of supplying 100% of the world's medical isotope demand. The second reactor would function primarily as a backup, to ensure that the supply of isotopes would not be interrupted by maintenance or unplanned
72:
An operational license for the MAPLE I reactor was granted in 1999, and the reactor went critical for the first time in early 2000. MAPLE II followed in the fall of 2003. Problems with the reactors during the testing period, most notably an unexpected positive
218:
The MAPLE facility was granted an extension on its operating license on 25 October 2007, which would permit operations until 31 October 2011. This (final) submission envisioned that the MAPLE I reactor would be operational in late 2008.
168:
new facility dedicated to the production of medical isotopes would be needed. A formal agreement was signed to begin the project in August 1996. Following a year-long environmental assessment, construction began in
December 1997.
156:
In the late 1980s, AECL began to acknowledge that continued isotope production would require the construction of a new reactor to replace capacity lost by the planned closing of the
148:
reactor, which came on-line in 1957. However, as these reactors began to age, it became clear that a new facility would be needed to continue the production of medical isotopes.
49:. It included two identical reactors, I and II, as well as the isotope-processing facilities necessary to produce a large portion of the world's medical isotopes, especially
227:
reactor to continue the production of medical isotopes. The statement left unclear what long-term direction AECL would take for its medical isotope production business.
453:
215:
and MDS Nordion added a further layer of complexity to the process. After considerable negotiation, AECL assumed full responsibility for the reactor in a settlement.
176:, and must be used within a few days of production. With treatments being constantly carried out around the globe, an uninterruptible supply was essential.
129:
are able to penetrate the skin of the patient, and deliver a greater portion of the dose directly to the tumor. The high neutron efficiency of the NRX's
183:) in the reactor, as well as from activists in the United States who fear that the uranium could be stolen by terrorists and used to fabricate a bomb.
114:
developed when it was realized that some of these artificially created isotopes could be used to diagnose and treat many diseases, especially cancers.
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possessed the world's most powerful research reactor. While the large neutron fluxes available in the reactor led to advances in such fields as
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budget was $ 140 million, but by 2005 it had already cost $ 300 million. Disputes over responsibility for the overruns between
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early in the new millennium. Design work on a replacement, originally under the name "Maple-X10", began in the late 1980s.
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MAPLE I achieving its first sustained reaction in
February 2000, and MAPLE II following in October 2003.
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With this promising start, AECL came to be a major world supplier of medical isotopes, using both the
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https://web.archive.org/web/20080618221319/http://www.aecl.ca/NewsRoom/News/Press-2008/080516.htm
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and neutron spectroscopy, many experiments were carried out involving the production of new
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shutdowns. This is made necessary by the nature of medical isotopes; many have short
137:(which had been previously used as a therapy source) to perform the same procedure.
77:, led to the cancellation of the project in 2008 and the shutdown of both reactors.
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Index of AECL submissions to the CNSC for licensing, and the subsequent decisions.
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691:
50:
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There had been some local opposition to the use of highly enriched uranium (
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Pioneering medical work done in the late 1940s and early 1950s established
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Press release of an agreement with INVAP for numerical modelling work
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2/19/99 Letter from
American group concerned about HEU use in MAPLE
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In addition, later testing found that the reactors have a positive
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October 2007 AECL submission to the CNSC, see Slide 8 on Page 4.
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PR Newswire report of AELC-MDS Nordion
Settlement (in brief)
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91:
41:), was a dedicated isotope-production facility built by
121:as a useful isotope, as the relatively high-energy
387:"AECL pulls plug on reactors after millions spent"
496:"Over budget, overdue and, perhaps, overdesigned"
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31:Multipurpose Applied Physics Lattice Experiment
360:Website of local group opposed to HEU in MAPLE
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19:"MAPLE" redirects here. For other uses, see
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160:in 1992, and the planned closing of the
16:Failed medical isotope reactor in Canada
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345:: CS1 maint: archived copy as title (
196:interfering with their free movement.
858:Nuclear Waste Management Organization
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451:Release confirming licence extension.
286:
500:Canadian Medical Association Journal
273:
13:
899:Canadian Nuclear Safety Commission
14:
988:
477:
946:
945:
201:power co-efficient of reactivity
75:power co-efficient of reactivity
972:Atomic Energy of Canada Limited
935:Anti-nuclear movement in Canada
879:Atomic Energy of Canada Limited
484:Article on early cobalt therapy
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385:McCarthy, Shawn (17 May 2008).
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894:Canadian Nuclear Association
584:Electricity sector in Canada
287:Myers, Terry (21 May 2008).
35:MDS Medical Isotope Reactors
7:
841:McArthur River uranium mine
655:Nuclear Power Demonstration
289:"AECL scraps Maple project"
244:How the MAPLE Reactors Work
125:produced when it undergoes
90:With the completion of the
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589:Nuclear industry in Canada
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807:Plasma Physics Laboratory
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914:Ontario Power Generation
909:Natural Resources Canada
863:Deep Geologic Repository
826:Uranium mining in Canada
792:Chalk River Laboratories
104:condensed matter physics
100:Chalk River Laboratories
802:Whiteshell Laboratories
579:Energy policy of Canada
568:Nuclear power in Canada
710:and prototype reactors
708:Research, experimental
21:MAPLE (disambiguation)
680:Power plant reactors
187:Project cancellation
797:McMaster University
512:10.1503/cmaj.080320
494:Magnus, B. (2008).
293:North Renfrew Times
785:Research locations
456:2008-01-05 at the
427:2008-05-24 at the
409:2008-06-16 at the
391:The Globe and Mail
327:on 22 January 2004
249:2008-03-22 at the
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320:. Archived from
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112:nuclear medicine
33:, later renamed
29:, short for the
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311:"Archived copy"
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110:. The field of
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506:(7): 813–4.
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329:. Retrieved
322:the original
318:anes.fiu.edu
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297:the original
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26:
25:
884:Bruce Power
131:heavy water
47:MDS Nordion
966:Categories
817:Fuel cycle
619:Darlington
231:References
174:half-lives
152:Beginnings
127:beta decay
123:gamma rays
86:Background
67:iodine-125
63:iodine-131
53:, medical
819:locations
624:Pickering
119:cobalt-60
59:xenon-133
55:cobalt-60
952:Category
762:SLOWPOKE
650:Gentilly
530:18362369
454:Archived
425:Archived
407:Archived
341:cite web
267:CBC News
247:Archived
205:meltdown
108:isotopes
521:2267837
81:History
889:Cameco
757:STOR-M
638:Closed
607:Active
528:
518:
331:22 May
135:radium
767:ZED-2
727:MAPLE
699:SGHWR
614:Bruce
325:(PDF)
314:(PDF)
27:MAPLE
772:ZEEP
722:IMSR
687:PHWR
526:PMID
347:link
333:2022
213:AECL
96:AECL
65:and
45:and
43:AECL
39:MMIR
752:PTR
747:NRU
742:NRX
737:MTF
732:MNR
516:PMC
508:doi
504:178
225:NRU
181:HEU
162:NRU
158:NRX
146:NRU
142:NRX
98:'s
92:NRX
968::
524:.
514:.
502:.
498:.
389:.
377:^
343:}}
339:{{
316:.
291:.
275:^
265:.
207:.
69:.
61:,
57:,
560:e
553:t
546:v
532:.
510::
393:.
349:)
335:.
269:.
37:(
23:.
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