Chalk River Information Bulletins
- NRU Status Report #67 - AECL provides update on NRU activities
(2010 July 28) AECL reports that progress continues on the NRU return-to-service activities. The return-to-service team has successfully loaded more than half the reactor fuel completing its first stage of fuel loading and has conducted the first of four assessments used to verify fuelling calculations. - NRU Status Report #66 - AECL provides update on NRU activities
(2010 July 21) AECL reports that progress continues on the NRU return-to-service activities. The return-to-service team has completed commissioning of startup instrumentation - specialized equipment required for the restart of the reactor after the extended outage. - NRU Status Report #65 - AECL provides update on NRU activities
(2010 July 14) AECL reports that progress continues on the NRU return-to-service activities. - NRU Status Report #64 - AECL provides update on NRU activities
(2010 July 07) On Monday July 5, 2010, AECL appeared before the Canadian Nuclear Safety Commission (CNSC) in a public hearing to consider AECL’s application for the restart of NRU. - NRU Status Report #63 - AECL provides update on NRU activities
(2010 June 30) AECL reports that the Technical Standards and Safety Authority (TSSA) has completed its inspections and assessments of the NRU weld repairs and the vessel’s fitness-for-service. - NRU Status Report #62 - AECL provides update on NRU activities
(2010 June 25) AECL reports that it made a request to the Canadian Nuclear Safety Commission (CNSC) to reschedule the previously announced public hearing date to consider AECL’s application for the restart of NRU. - NRU Status Report #61 - AECL provides update on NRU activities
(2010 June 23) AECL reports that restart activities for the NRU Return-to-Service project are ongoing and that the NRU vessel has been refilled to its operating level. - NRU Status Report #60 - AECL provides update on NRU activities
(2010 June 16) AECL reports that one hundred per cent (100%) of the NRU weld repairs are now complete. During the past week, the repair team completed the finishing weld and a series of non-destructive examinations (NDE) of the final repair site. - NRU Status Report #59 - AECL provides update on NRU activities
(2010 June 09) AECL reports that the NRU weld repairs remain at ninety-eight per cent complete as work continues to address a single imperfection that was identified during non-destructive examination (NDE) of the final weld repair. - NRU Status Report #58 - AECL provides update on NRU activities
(2010 June 02) AECL reports that ninety-eight per cent of the NRU weld repairs are now complete. - NRU Status Report #57 - AECL provides update on NRU activities
(2010 May 26) AECL reports that the final and most challenging weld repair was applied to the NRU vessel over the weekend. Ninety-three per cent of the NRU weld repair activities are now complete. - NRU Status Report #56 - AECL provides update on NRU activities
(2010 May 19) AECL reports that work on the final repair site has commenced and to date 77 per cent of the NRU weld repairs and associated Non-Destructive Examinations (NDE) have been completed. - Loss of waste water from transfer tank
(2010 May 14) AECL reports a loss of approximately 5,220 litres of waste water from an underground transfer tank used by the waste treatment centre located at the Chalk River site. - NRU Status Report #55 - AECL provides update on NRU activities
(2010 May 12) AECL reports that 71 per cent of the weld repairs and associated Non-Destructive Examinations (NDE) have been completed. - NRU Status Report #54 - AECL provides update on NRU activities
(2010 May 05) AECL reports that 71 per cent of the weld repairs and associated Non-Destructive Examinations (NDE) have been completed. - Information Bulletin - Loss of Refrigerant
(2010 April 30) AECL reports a loss of approximately 775 kg of R-134A refrigerant from the MR-3 Experimental Loop. - NRU Status Report #53 - AECL provides update on NRU activities
(2010 April 28) AECL reports that 71 per cent of the weld repairs and associated Non-Destructive Examinations (NDE) have been completed. - Information Bulletin - Heavy Water Spill
(2010 April 27) During activities to refill the NRU Main Heavy Water Circuit in preparation for returning the reactor to service, approximately 42 litres of new inventory of heavy water was spilled within the NRU facility. - NRU Status Report #52 - AECL provides update on NRU activities
(2010 April 21) The repair phase of the project began on December 12, 2009. AECL reports that non-destructive examination (NDE) of the most recent repair is nearing completion bringing the total per cent of repair and associated NDE completed to date to 69 per cent, up from the 65 per cent reported last week. - NRU Status Report #51 - AECL provides update on NRU activities
(2010 April 14) The repair phase of the project began on December 12, 2009. To date 65 per cent of the repair work and associated non-destructive examinations have been completed. - NRU Status Report #50 - AECL provides update on NRU activities
(2010 April 07) The repair phase of the project began on December 12, 2009. To date 65 per cent of the repair work and associated non-destructive examinations have been completed. - NRU Status Report #49 - AECL provides update on NRU activities
(2010 March 31) The repair phase of the project began on December 12, 2009. AECL has successfully completed eight of ten weld site repairs. Work on the ninth repair site is in progress and is nearing completion. - NRU Status Report #48 - AECL provides update on NRU activities
(2010 March 25) The repair phase of the project began on December 12, 2009. AECL has successfully completed eight of ten weld site repairs representing more than half (56%) of the repair work necessary in order to return the NRU to service. - NRU Status Report #47 - AECL provides update on NRU activities
(2010 March 17) AECL reports that NRU reactor vessel repair activities continue. The overall repair process began on December 12, 2009. To date, 51 per cent of the repair activities and associated post-repair examinations have been completed. - NRU Status Report #46 - AECL provides update on NRU activities
(2010 March 10) AECL reports that NRU reactor vessel repair activities continue. The overall repair process began on December 12, 2009. - NRU Status Report #45 - AECL provides update on NRU activities
(2010 March 03) AECL reports that NRU reactor vessel repair activities continue. The overall repair process began on December 12, 2009. - NRU Status Report #44 - AECL provides update on NRU activities
(2010 February 24) AECL reports that NRU reactor vessel repair activities continue. The overall repair process began on December 12, 2009. - Contamination Incidents
(2010 February 24) AECL reports that during the past week, two incidents involving AECL employees and exposure to radioactive contamination have occurred. - NRU Status Report #43 - AECL provides update on NRU activities
(2010 February 17) AECL reports that NRU reactor vessel repair activities continue. The repair team completed the non-destructive examination of the second horizontal weld repair and is preparing the vessel for the next series of repairs. - NRU Status Report #42 - AECL provides update on NRU activities
(2010 February 10) AECL reports that NRU reactor vessel repair activities continue. The repair team completed its second horizontal weld repair and is preparing the vessel for the next series of repairs. - NRU Status Report #41 - AECL provides update on NRU activities
(2010 February 03) AECL reports that NRU reactor vessel repair activities continue. The repair team completed its first horizontal weld repair and are preparing the vessel for the next series of horizontal weld repairs. - NRU Status Report #40 - AECL provides update on NRU activities
(2010 January 27) AECL reports that the NRU reactor vessel repair activities are currently focused on preparation work in advance of the next series of weld repairs. - NRU Status Report #39 - AECL provides update on NRU activities
(2010 January 20) AECL reports that the NRU reactor vessel repair activities are currently focused on preparation work in advance of the next series of weld repairs. - NRU Status Report #38 - AECL provides update on NRU activities
(2010 January 13) AECL reports that the NRU reactor vessel repair activities are currently focused on preparation work in advance of the next series of weld repairs that will use horizontal welding machines. - NRU Status Report #37 - AECL provides update on NRU activities
(2010 January 06) AECL reports that NRU reactor vessel repair activities continue to progress at the Chalk River Laboratories. - NRU Status Report #36 - AECL provides update on NRU activities
(2009 December 30) AECL reports that repairs to the NRU reactor vessel continue to progress at the Chalk River Laboratories. - NRU Status Report #35 - AECL provides update on NRU activities
(2009 December 23) Repairs to the NRU reactor vessel continue at the Chalk River Laboratories, with approximately 11 per cent of the planned repairs completed to date. - NRU Status Report #34 - AECL provides update on NRU activities
(2009 December 16) AECL confirms that the first weld build-up repair on the NRU reactor vessel was performed on December 12th. - NRU Status Report #33 - AECL provides update on NRU activities
(2009 December 09) - NRU Status Report #32 - AECL provides update on NRU activities
(2009 December 02) The specialized tooling and equipment for the weld repair has now been installed at the NRU reactor. - NRU Status Report #31 - AECL provides update on NRU activities
(2009 November 25) Welder training and weld equipment testing and verification in the NRU facility mock-up is now complete. - NRU Status Report #30 - AECL provides update on NRU activities
(2009 November 18) AECL continues to train welders and prepare equipment prior to commencing in-vessel repairs. - NRU Status Report #29 - AECL provides update on NRU activities
(2009 November 11) AECL has installed the first set of welding tools and equipment in the full height mock-up at Chalk River's NRX facility. - NRU Status Report #28 - AECL provides update on NRU activities
(2009 November 04) The first set of welding tools and equipment, developed in partnership by AECL and Liburdi Engineering of Dundas, Ontario, has arrived at the Chalk River Laboratories. - NRU Status Report #27 - AECL provides update on NRU activities
(2009 October 28) Vessel cleaning activities for the six sites requiring localized repair is complete and preparations are underway to conduct additional cleaning as necessary. - NRU Status Report #26 - AECL provides update on NRU activities
(2009 October 21) Cleaning activities are approximately 88 per cent complete. Progress on this activity has been made possible through the use of the customized tooling designed and built by AECL staff working at the Chalk River Laboratories. - NRU Status Report #25 - AECL provides update on NRU activities
(2009 October 14) In preparation of the upcoming weld build-up repair, cleaning of the NRU reactor vessel is progressing. - NRU Status Report #24 - AECL provides update on NRU activities
(2009 October 07) This week AECL completed the Phase II Non-Destructive Examination (NDE) data analysis. Examination of the data confirms that only six sites within the vessel require localized repair. - NRU Status Report #23 - AECL provides update on NRU activities
(2009 September 30) The Phase IV NDE probe tool testing and training is complete and collection of in-vessel Phase IV data is underway. - NRU Status Report #22 - AECL provides update on NRU activities
(2009 September 23) Data analysis continues on Phase II Non Destructive Examinations (NDE). Phase III analysis is complete and findings confirm there is no degradation of the upper portions of the NRU vessel wall. - Airborne monitoring results
(2009 September 23) As part of routine airborne monitoring, it was determined that an airborne tritium emission occurred through the Waste Treatment Centre (WTC) ventilation system. - NRU Status Report #21 - AECL provides update on NRU activities
(2009 September 16) Data analysis continues on Phases II and III of the Non Destructive Examinations (NDE). Probe development is nearing completion and preparations are underway to commence Phase IV NDE at the base of the vessel. - NRU Status Report #20 - AECL provides update on NRU activities
(2009 September 09) Data analysis continues on Phase II and III of the Non Destructive Examinations (NDE). Phase II included scans of the entire vessel circumference and Phase III included five vertical scans from the bottom to the top of the interior wall of the vessel. One additional vertical scan is planned. - NRU Status Report #19 - AECL provides update on NRU activities
(2009 September 02) AECL’s NDE team has now completed the third stage of examinations of the vessel wall using special tooling for vertical inspection. NDE analysis activities remain on schedule. - NRU Status Report #18 - AECL provides update on NRU activities
(2009 August 26) Non-Destructive Examination (NDE) inspections of the NRU reactor using the Mark II tool are now complete and a large quantity of data has been obtained for analysis. - NRU Status Report #17 - AECL provides update on NRU activities
(2009 August 19) The CNSC has determined that Commission approval will be required prior to AECL re-fuelling the reactor. - NRU Status Report #16 - AECL provides updated guidance on NRU return to service
(2009 August 12) Detailed analysis of Non Destructive Examination (NDE) data collected to date confirms nine sites likely requiring repair. - NRU Status Report #15 - AECL provides update on NRU activities
(2009 August 05) A detailed analysis of the Non Destructive Examination (NDE) data collected to date continues. Results of this analysis have been provided to the vendors to support their tooling development. - AECL provides NRU Video Status Update
(2009 August 04) AECL releases two video updates of its National Research Universal (NRU) Return to Service Plan activities, including a more detailed look at the non-destructive examinations currently under way at Chalk River Laboratories. - NRU Status Report #14 - AECL provides update on NRU activities
(2009 July 29) Work continues with specialized vendors on proving repair tooling designs, fabrication of equipment, and cleaning techniques. - NRU Status Report #13 - AECL provides update on NRU activities
(2009 July 22) Analysis of the data collected from Non Destructive Examinations (NDE) of the interior of the vessel continues. - NRU Status Report #12 – AECL provides update on NRU activities
(2009 July 15) Non Destructive Examinations (NDE) of the interior of the reactor vessel continues with approximately 80 per cent of the vessel circumference surveyed. - Airborne monitoring results
(2009 July 14) Ongoing monitoring of the heavy water leak from the NRU reactor vessel continues. As was reported in previous Information Bulletins, a small portion of the leakage continues to evaporate and results in a monitored airborne tritium release through the NRU reactor ventilation system. - NRU Status Report #11 - Most current assessment of Chalk River NRU reactor allows for revised guidance on timeline for return to service
(2009 July 08) AECL today announced that as a result of the most recent data from the ongoing assessment of the National Research Universal (NRU) reactor condition and the development of a critical path for the various repair options, it is now clear that the NRU will not return to service before late 2009. - NRU Status Report #10 - AECL provides update on NRU activities
(2009 July 02) Non Destructive Examinations (NDE) of the interior of the aluminium vessel continues. - Airborne monitoring results
(2009 June 26) As reported in NRU Status Report #9 on Wednesday, June 24th, the heavy water level in the reactor vessel has been lowered and the heavy water leak rate has been reduced to a flow of less than 0.5 kg/hr. - NRU Status Report #9 - AECL provides update on NRU activities
(2009 June 24) AECL reports that removal of all fuel, control and isotope rods has been completed. - NRU Status Report #8 - AECL provides update on NRU activities
(2009 June 17) AECL reports that removal of the last NRU fuel rod was successfully completed June 15. - NRU Status Report #7 - AECL provides update on NRU activities
(June 10) AECL provides the following status report on the unplanned shutdown of the NRU reactor at its Chalk River Laboratories. - NRU Status Report #6 - AECL begins removal of fuel rods on NRU reactor
(2009 June 02) AECL today announced it has begun the process of removing fuel rods from the NRU reactor as part of the process to repair the reactor and return it to service. - Status Report #5 - AECL provides update on the NRU reactor
(2009 May 27) AECL provides the following status report on the unplanned shutdown of the NRU reactor at its Chalk River Laboratories. - NRU Status Report #4 - AECL provides update on NRU activities
(2009 May 22) AECL provides the following update of activities related to the unplanned shutdown of NRU at Chalk River Laboratories. - NRU Status Report #3 - Unplanned shutdown of NRU reactor extended
(May 18) AECL reported on Friday, May 15th that the NRU reactor was safely shut down on Thursday, May 14th due to a loss of electrical power that occurred in parts of eastern Ontario and western Quebec. - NRU Status Report #2
(2009 May 17) The following is an update regarding a small contained Heavy Water leak within the NRU reactor facility, as reported on May 15, 2009. - NRU Status Report
(2009 May 15) On Thursday, May 14th, a loss of electrical power occurred in parts of eastern Ontario and western Quebec. As a result of the loss of power, the NRU reactor at AECL’s Chalk River facility was safely shut down. - AECL confirms sewage waste processing equipment contamination-free
(2009 May 07) As part of routine sewage handling at the Chalk River Laboratories (CRL), sludge slurry is collected, monitored and stored in a holding tank until it is de-watered. The resulting de-watered material is safely stored on site. - Loss of refrigerant in NRU reported under AECL protocol of voluntary disclosure
(2009 March 20) During routine operational checks on March 5, 2009, a temperature gauge on a component outside of the NRU reactor associated with isotope production indicated a warmer temperature than expected. - AECL reports routine monitoring detected small amounts of heavy water containing tritium within the NRU
(2009 February 23) AECL reports that routine monitoring has detected small amounts of heavy water containing tritium within the NRU reactor building’s ventilation system. - Status Report - NRU Reactor returned to service
(2009 February 17) AECL reports that the NRU reactor was safely returned to service early in the afternoon on Tuesday, February 17th, following an unscheduled outage to repair the mechanism to extract medical isotope rods from the reactor. - NRU Status Report
(2009 February 16) AECL reports that the NRU reactor was taken out of service on Sunday, February 15th, in order to repair the mechanism to extract medical isotope rods from the reactor.

Community EnquiriesPat Quinn, Manager, Site & Community Affairs
Phone: (613) 584-8500
Toll free: 1-800-364-6989

NRUCanada.ca: Marking our progress
In keeping with our mandate of providing regular communications updates on AECL's NRU return to service plan, we have launched a new website to help you better understand the complexities and importance of returning the reactor to service as soon as safely possible.