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HomeMy WebLinkAboutPSD-073-05 . Clwiogton REPORT PLANNING SERVICES Meeting: GENERAL PURPOSE AND ADMINISTRATION COMMITTEE Date: Monday, June 6, 2005 Report #: PSD-073-05 File#: PLN 33.4.6 Ke'J1/ {jJ!l;;J5r;.-U:';- By-law #: Subject: CANADIAN NUCLEAR SAFETY COMMISSION DRAFT REGULATORY GUIDE G - 320 - ASSESSING THE LONG TERM SAFETY OF RADIOACTIVE WASTE MANAGEMENT RECOMMENDATIONS: It is respectfully recommended that the General Purpose and Administration Committee recommend to Council the following: 1. THAT Report PSD-073-05 be received; 2. THAT Report PSD-073-05 be approved as the comments of the Municipality of Clarington on Draft Regulatory Guide G-320, Assessing the Long Term Safety of Radioactive Waste Management; 3. THAT a copy of Council's decision and Report PSD-073-05 be forwarded to the Canadian Nuclear Safety Commission, the Low-Level Radioactive Waste Management Office, the Nuclear Waste Management Organization, and the South East Clarington Rate Payers Association FORTHWITH. Submitted by: l ", L D. . /" Q, e"-.!~ Reviewed by: '---J {~(,- - Franklin Wu Chief Administrative Officer vi ~. Creme, M.C.I.P.,R.P.P. Director, Planning Services JAS*FL *DJC*df 26 May 2005 CORPORATION OF THE MUNICIPALITY OF CLARINGTON 40 TEMPERANCE STREET, BOWMANVILLE, ONTARIO L 1 C 3A6 T (905)623-3379 F (905) 623-0830 REPORT NO.: PSD-073.05 PAGE 2 1.0 PURPOSE OF REPORT 1.1 On May 2, 2005, Council considered correspondence from the Canadian Nuclear Safety Commission (CNSC) forwarding a copy of Draft Regulatory Guide G-320 entitled Assessing the Long Term Safety of Radioactive Waste Management, and requesting comments by June 6, 2005. This report has been prepared in response to Council's direction to prepare a report on the Draft Regulatory Guide. Staff has been assisted in this review by Hardy Stevenson and Associates, the peer review team for the Port Granby Project (see Attachment 1). The Municipality's comments on the draft Regulatory Guide are provided in bold italics. A glossary of terms use in this report is provided as Attachment 2. A copy of draft Regulatory Guide is available for review under separate cover. A copy of this report has already been forwarded to the CNSC in order to meet the deadline for comments, with the caveat that Council will be reviewing the comments and providing final approval on June 6th. 2.0 BACKGROUND 2.1 The CNSC was created in 1997 by the Nuclear Safety and Control Act (NSCA), replacing the Atomic Energy Control Board. It is an independent regulatory agency of the Government of Canada and is the lead federal agency overseeing operations by the nuclear industry in Canada. Operating within the mandate and authority of the NSCA, the CNSC regulates all activities relating to nuclear materials, equipment and processes within Canada. This regulatory regime covers the entire nuclear substance lifecycle, from production and use to final disposal. 2.2 The CNSC's legal framework is supported by a number of regulatory documents, including Regulatory Guides and Regulatory Standards. Regulatory Guides, provide guidance to licensees and other stakeholders and indicate acceptable ways of meeting the CNSC's requirements. In contrast, Regulatory Standards describe CNSC requirements and impose obligations on the regulated party. 2.3 Regulatory Guide G-320, once approved, will apply to both the Port Granby Project (long term storage of low level radioactive waste) and the Nuclear Waste Management Organization (NWMO) process (long term storage and disposal of high level radioactive waste). 3.0 OVERVIEW OF DRAFT REGULATORY GUIDE G-320 3.1 The purpose of Regulatory Guide G-320 is to assist licensees and applicants in determining ways to assess the impacts that radioactive waste storage and disposal methods have on the environment and on the health and safety of people in the long term. Long term safety assessments are used to give reasonable assurance that proposed plans for the long term management of radioactive waste are consistent with REPORT NO.: PSO-073-05 PAGE 3 CNSC requirements for protecting the environment and the health and safety of humans. The definition of long term provided in the draft Guide is as follows: "In radioactive waste disposal, a period of time that exceeds the time during which active institutional control can be expected to last". 3.2 In preparing the draft Regulatory Guide, the CNSC drew on documents prepared by the International Atomic Energy Agency (IAEA) and the Organization for Economic Cooperation and Development (OECD) Nuclear Energy Agency. The Guide sets out typical ways to assess the impacts that radioactive waste storage and disposal methods have on the environment and on the health and safety of people, in order to provide reasonable assurance of long term safety. The methods described are not equally applicable to every assessment, and this non-prescriptive approach to regulation allows the licence applicant to determine the approach that is appropriate for his specific circumstances. However, applicants must justify their application of the guidance provided in the Regulatory Guide. 3.3 Concepts for the long term management of radioactive waste are based on containment and isolation of the waste, whether it is in storage or disposal facilities. Storage is defined as "the holding of spent fuel or radioactive waste in a facility that provides for its containment, with the intention of retrieval". Disposal is defined as the "emplacement of waste without the intention of retrieval". 3.4 The design of a long term facility or system, as well as the comparison of options, is expected to be optimized so that all reasonable precautions have been taken and radiological exposures have been minimized in order to protect the environment and human health and safety. This approach is commonly termed the ALARA principle (As Low As Reasonably Achievable). The design is also expected to be optimized to remain below the minimum regulatory limits by some factor of safety. This is necessitated by the uncertainty in making long term predictions and the possibility of multiple exposures to contamination from other sources. 3.5 All facilities must have a decommissioning plan in place that identifies the end-state of the facility and site and the activities to achieve that end-state, and an assessment of the potential effects of the proposed decommissioning program. The decommissioning plan forms the basis for the financial guarantee, which is required to ensure that there will be funds available to implement the decommissioning plan and to prevent any financial burden on future generations. Comments The draft Guide should provide a definition of 'long term' that more accurately reflects the guidance provided. As such, the definition should be expanded beyond the disposal of radioactive waste to also encompass long term storage. It is also not appropriate to associate the definition of 'long term' with the institutional control period since some storage facilities could require active institutional control for several hundred years until the waste is ultimately disposed of in a permanent facility. For example, the new Port Granby Waste Management Facility is a storage facility and the waste will need to be relocated REPORT NO.: PSD-073-05 PAGE 4 after several hundred years when the new facility reaches the end of its active life. The draft Guide does not provide specific guidance regarding the mmlmum facility life required before the Guide is triggered. It makes very little distinction between the assessment requirements for 'storage' and 'disposal' facilities, although the differences in time frames can be substantial as evidenced by the Port Granby Project (several hundred years) and the NWMO process (100,000 + years). This lack of distinction could be significant, since presumably the assessment for a disposal facility would require a greater degree of sophistication. As a result, a licensee may over-estimate the assessment requirements for a storage facility. Alternatively, the licensee may under-estimate the assessment needs for a storage facility in terms of active systems, operation and maintenance, and waste retrieval requirements. Similarly, the draft Guide does not specifically define how the differing hazard level between high level waste (used nuclear fuel rods) and low level waste would affect assessment requirements. For example, the document does not discuss heat removal and the thermo-mechanical effects on structures and geology which are significant assessment issues for high-level waste related to either storage or disposal. The benefit of requtrlng that ALARA assessments be carried out for the comparison of options is questionable. In most instances, ALARA optimization can only be done when the design has advanced to a detailed stage, as there may not be adequate information during the screening of options. This requirement would put excessive requirements onto the facility design at the concept selection stage with unnecessary implications on project costs with questionable added benefit. The discussion in the draft Guide on the decommissioning plan should recognize that the plan is based on current technology and not assumptions with regard to future technology. It should also recognize the inability to predict the future plan in precise terms particularly where the decommissioning could be several hundred years or more into the future. In such cases, decommissioning plans could be provided only at a conceptual level and consideration would be required regarding financial requirements and viability of financial guarantees over the long term. The glossary provided at the back of the draft Guide should be expanded to include definitions for 'Class I facilities', 'Class II facilities', 'decommissioning~ and 'environment'. These definitions are particularly important to the proper interpretation of the Guide. REPORT NO.: PSD-073-05 PAGE 5 3.6 Guidance on Performinq Lonq Term Assessments 3.6.1 The draft Regulatory Guide sets out typical ways to assess the impacts that radioactive waste storage and disposal methods have on the environment and on the health and safety of people in the long term. It provides guidance on a number of matters as discussed below. 3.6.2 Assessment Methodoloqies. Structure and Approach The purpose of the assessment will determine the approach used to assess long term safety. Methods discussed include: . Conservative Calculations - intentionally over-estimating future consequences . Scoping and Bounding Assessments - identifying aspects of the waste management system critical to safety, and estimating the system's performance limits . Natural Analogs - assessing natural situations that are similar to the waste management system proposed . Deterministic and Probabilistic Models - using a mathematical approach to analyze scenarios in the safety case while addressing uncertainty in the data, and identifying the likelihood of a magnitude of a certain consequence occurring. 3.6.3 Svstem Description The physical environment where the proposed waste management facility or system is to be located should be described, including geological, biological, climatic conditions and existing land use. This information is to be sufficiently detailed to allow the development of site-specific models that will simulate, with some reliability, the response of the site to disturbances caused by the facility/system. The proposed waste management system should also be described to provide a clear understanding of how safety and environmental protection will be achieved. This includes engineered and natural barriers, and active and passive institutional controls to limit access and exposure to the contaminants. As licensing progresses through a facility's Iifecycle (ie. site preparation, construction, operation, decommissioning, and abandonment), the understanding of both the site and the facility will improve. Assessment models should be updated and refined as the facility moves through its lifecycle. Comments The requirements for site characterization emphasize the physical environment, with no mention of the social or economic environment that may be affected. Since the assessment is intended to evaluate the response of the site to the disruption caused by the waste management facility, the socio-economic environment should be included in the description of the site. As well, given the REPORT NO.: PSD-073-05 PAGE 6 time frames contemplated for long term facilities, 'current and foreseeable uses' should be described rather than 'existing land use'. The draft Guide defines 'waste management system' as wa system for collecting, transporting, receiving, treating, processing, storing or disposing the wastes that are produced as a result of a licensed activity. W However, the guidance provided in the document largely focuses on the actual waste management facility. It should provide more guidance on the other activities involved in radioactive waste management, such as waste characterization, waste transportation, monitoring and surveillance, and waste retrieval. It is not clear how the updating and refinement of assessments over the project lifecycle will be carried out in practice. If the assessments turn out to be inadequate as the project moves through the lifecycle, the implications could be enormous and unacceptable. To pre-empt this possibility, all issues must be resolved early before the construction licence is issued. Following construction, only follow-up monitoring would be of value to confirm the findings of the assessment and ensure safety. There may also be instances where assessments could be verified through a wdemonstrationw phase prior to full-scale construction of the facility. 3.6.4 Assessment Time Frames The determination of the appropriate time periods to be used in the assessment is to be based on: . The hazardous lifetime of the waste . Duration of the operational period before the facility reaches its end state . The design life of the engineered barriers . The frequency of natural events (eg. earthquakes, glaciation) and human-induced environmental changes (eg. climate change), and . Duration of both active and passive institutional controls. Active institutional controls include measures such as monitoring, surveillance and maintenance, while passive controls include restricted access to the site. Disposal options should not rely on institutional controls for longer than a few hundred years unless absolutely necessary. Passive barriers to provide containment and isolation are preferred, given the uncertainties associated with future human activities. 3.6.5 Assessment Scenarios A scenario is an assumed set of future conditions or events. Scenarios to be used in an assessment should be developed through a structured analysis of current and future conditions of site characteristics, waste properties, and receptor characteristics and their lifestyles. Scenarios should include normal evolution (expected processes and events), extreme conditions (eg. climate change, drought or excessive rainfall), natural REPORT NO.: PSD-073-05 PAGE 7 disruptive events (eg. flood, seismic activity), and containment failure, including human intrusion (see Section 3.5.6). 3.6.6 Human Intrusion Scenarios involving human intrusion into a waste facility assume the penetration of barriers and the possible release of contaminants and exposure of the public, the environment and the intruder. The assessment is expected to estimate the exposure from the release of contaminants, but only scenarios of inadvertent human intrusion need to consider the exposure to the intruder. Reasonable efforts are expected to limit the dose in an intrusion scenario and to reduce the probability of that intrusion occurring. Comment The generic approach to the discussion on human intrusion in the draft Guide does not recognize that the nature of the intrusion and the extent of the exposure may be different for deliberate and inadvertent intrusions, and therefore should have different assessment requirements. The Guide should also recognize that deliberate intrusions may have either a criminal intent (eg. terrorism) or a less malicious intent (eg. vandalism). The Guide indicates that the risk to an intruder from exposure to the contamination should be ignored. This approach would not appear to be warranted, given that not all planned intrusions may have criminal intent. Facility safety in the post-intrusion phase should also be assessed, particularly if the intruder goes undetected. As well, lesser intrusions could also occur external to the facility, such as the digging of wells in the surrounding areas, which may have radiological and environmental impacts. 3.6.7 Receptors and Critical Groups The draft Guide defines a receptor as "any environmental entity that is exposed to, and could be adversely affected by, radiation or a hazardous substance, or both. A receptor is usually an organism or a population, but it could also be an abiotic entity such as surface water or sediment." Assessment scenarios are expected to include the identification of human and environmental receptors that may be exposed to radioactive and hazardous substances. Human receptors may be based on the International Commission on Radiological Protection (ICRP) concept of a critical group, which is a group of people representative of those individuals in the population that could potentially receive the highest annual radiological dose. The habits and characteristics assumed for this group should be reasonably conservative and plausible. REPORT NO.: PSD-073-05 PAGE 8 The no-human receptor situation differs from humans even when all receptors are present in the same environment at the same time. This is due to the large variety of organisms with different shapes and sizes, exposure pathways and sensitivities. Each scenario that is analyzed may have different critical groups and environmental receptors. Comments The definition of 'receptor' should be expanded to include "human beings and their socio-economic and cultural circumstances". The existing terms 'environmental entity' and 'population' could potentially limit the analysis of impacts on people who may be affected. 3.6.8 Assessment Models Long term assessments usually employ a variety of computer models to predict future conditions. Since the accuracy of predictions made in long term assessments cannot be confirmed, the assessment models and input data need to be rigorously tested and evaluated. As well, the complexity and spatial variability of the natural environment make it difficult to develop an unambiguous model of a system. Accordingly, the model evaluation process should concentrate on identifying and understanding the key physical, chemical and biological processes that are important to safety at the various spatial and time scales of concern. A number of additional methods, such as peer review, can be used to increase confidence in the results of an assessment model. 3.6.9 Interpretation of Assessment Results The results of the assessment model should be interpreted with respect to what is understood about the site, the waste management system and its underlying science and engineering. The results should also be analyzed to demonstrate consistency with expectations of system performance. Any discrepancies or unexpected results should be investigated and explained, and sources of uncertainty in the results should be analyzed. 4.0 CONCLUSIONS 4.1 The CNSC has drawn heavily on international experience in developing the Regulatory Guide G-320. The document is well drafted and will provide substantial guidance to the licensee regarding the expectations of the CNSC with respect to assessment requirements. The Guide also provides the Municipality of Clarington and other stakeholders in both the Port Hope Area Initiative and the NWMO process with a better understanding of the stringent requirements that an applicant must address in order to obtain a license from the CNSC. In the case of the Port Granby Project, a construction license could be issued as early as 2006, while CNSC approvals for the NWMO project are still a number of years away. REPORT NO.: PSD-073-05 PAGE 9 Attachments: Attachment 1 - Attachment 2 - Attachment 3 - Memo from Hardy Stevenson and Associates Limited Glossary of Terms Draft Regulatory Guide G-320, Assessing the Long Term Safety of Radioactive Waste Management (under separate cover) List of interested parties to be advised of Council's decision: Canadian Nuclear Safety Commission Low- Level Radioactive Waste Management Office Nuclear Waste Management Organization South East Clarington Rate Payers Association ATTACHMENT 1 Report PSD-073-05 Memorandum To: Janice Szwarz, Senior Planner, Special Projects, Municipality of Clarington From: Catherine Beck, Community Environmental Planner cc: Dave Hardy, Principal, Hardy Stevenson and Associates Limited; Marc Rose, Project Manager, Hardy Stevenson and Associates Limited Date: 24 May 2005 Subject: Comments on CNSC's Draft Regulatory Guide "Assessing the Long Term Safety of Radioactive Waste Management", G-320, issued for Public Comment, April 2005 Hardy Stevenson and Associates Limited is pleased to provide comments about CNSC G-320 put forward by the two senior professionals on the Municipal Peer Review Team whose specializations relate to epidemiology, health physics, and nuclear physics. From our perspective, the knowledge of Dr. Murray Finkelstein and Dr. Mohan Rao is most germane to the document's subject. Mr. Dave Hardy has reviewed this memo and has provided additional minor comments. We trust you will find the comments helpful. General Comments: The G-320 document is well drafted and provides substantial information to the licensee in the development of the application for a long-term radioactive waste management facility. We are pleased to provide the following comments on its content and potential usefulness as requested and hope the comments would assist the CNSC in the further development of the draft regulatory document. We note that there is very little distinction made between storage and disposal with respect to assessment requirements. There are no exceptions stated (i.e., is there a minimum life of the facility for the Guide to trigger?). There is a significant potential for a licensee to "overestimate" assessment requirements for storage facilities that may not require the same degree of sophistication as for long-term disposal facilities. It is also plausible that the licensee may underestimate assessment needs in terms of storage-related items such as in the safety assessment of "active" systems, operation and maintenance, and waste retrieval requirements for storage facilities. In keeping with the definition of "waste management", we feel that the document should provide some guidance to various activities involved in radioactive waste management besides the facility development. Such activities include waste characterization, waste transportation, monitoring and surveillance, and waste retrieval. We found the document largely focuses on the facility per se. The document does not discuss heat removal and thermo-mechanical effects on structures and geology, which are significant assessment issues for high-level waste related to either storage or disposal. The document does not seem to explicitly discuss assessments needed with regard to acts of terrorism and potential breach of international safeguards. Specific Comments: Page 3, para 1. The discussion on the decommissioning plan should recognize that the plan be based on current technology (and not assumptions with regard to future technologies). It should also recognize the inability to predict the future plan in precise terms particularly where the decommissioning could be several hundred years into the future, In such cases, decommissioning plans could be provided only at a conceptual level and consideration would be required as to the financial requirements and viability of financial guarantees over the long term. Page 3. para 2. We suggest that the terminology be expanded to include definitions for Class I and Class II facilities, decommissioning and environment. These definitions are particularly important in properly interpreting the Guide. Page 3. para 3. Item 1. Is "disposed of' the appropriate term for the long term management of mine and mill tailings in aboveground facilities? Although there may not be an intention to retrieve these wastes, there could be an ongoing need to monitor and refurbish the facilities. It is also possible that future generations may retrieve these wastes and manage them in different types offacilities (e.g., mined facilities). Page 3. para 5, The assessment of waste management systems should include selecting a suitable site as one of the goals, Site selection, characterization and site-related safety assessments are significant activities for most long- term waste management systems, Page 4. para 1. The term "post-decommissioning" is ambiguous ("restoration of the site" may be a better term). Page 5. para 4. It is questionable if the ALARA assessments should be carried out for the comparison of options as implied in the text. In most instances, ALARA optimisation can only be done when the design has advanced to a detailed stage, as there may not be adequate information during the screening of options. In requiring ALARA optimisation during the comparison of options, we feel that the Guide would be putting excessive requirements onto the facility design at the concept selection stage with unnecessary implications on project costs and questionable additional benefit. Page 5. para 5. Please explain why collective dose is not a regulatory criterion. Page 6. para ]. The expectation with respect to system optimisation is necessitated by the Radiation Protection Regulations as well (i.e., ALARA). Page 6. para 4. It is stated that reasoned arguments can include reliance on institutional controls to ensure safety if design features and passive safety features are not adequate. This statement is necessarily contingent on the length of the institutional control period that would be acceptable for the subject case (several hundred years?). Obviously perpetual institutional control would not be meaningful. Some clarification on the institutional control period would be useful. Page 6. para 5. Independent analysis by the CNSC staff and expert judgement based on CNSC staff training and experience would not be available to the licensee until the licence application is made, unless the CNSC intends to pro-actively involve itself in the preparation the license application. Page 7, para 4. Nowhere in the report is it mentioned that the radiological public dose limit of I mSv/a is over and above the natural background. Page 7, para 6. In earlier regulatory guides on geological disposal, the CNSC appears to have used 10,6 as the radiological risk criterion. It may be useful to put the new risk criterion in proper context with respect to the earlier figure. Furthermore, why is the CNSC prescribing an acceptable target (0.14 mSv/a)? Should this not be left to the licensee to decide based on the specifics of the design? Page 8. para 3. It is necessary to state that the assessment end points reflect the effects of the project on the environment rather than the net effect (i.e., There may be instances where non-radiological status of the environment exceeds assessment end points to start with). Page 9. para I. Are these really "alternative" indicators, or are these additional indicators? Some of these look like starting assumptions rather than indicators. Page 10. para 2. The assessment tools and techniques could include comparable licensed benchmarks and international benchmarking studies. Page I L para 2. The limits for identified contaminants of concern are based on environmental legislations/guidelines rather than on social acceptability. Page II. para 6. "The value of the computed result determines whether the model structure and input data are conservative." This seems like circular reasoning. How does one know "a priori" what the result should be. It seems to me that one should apply conservative models and inputs, and the computed result is then the result of upstream conservatism, not a determinant of whether the models and inputs were conservative. Page 14, para 4. It is not clear how the updating and refinement of assessments over the project lifecycle will be carried out in practice. If the assessments turn out to be inadequate as the project moves through the Iifecycle, the implications could be enormous and unacceptable. To pre-empt this possibility, it is necessary that all issues be resolved early before the construction license. Following construction, only follow-up monitoring would be of value to confirm the findings of the assessment and ensure safety. Furthermore, there may be instances where assessments could be verified through a "demonstration" phase prior to full-scale construction of the facility. Page IS, para I Item 6 on the list cites "existing land use". The Municipalities associated with the Port Hope Area Initiative have found the term'.. . current and foreseeable uses...' to be much more effective in developing scenarios pertaining to site characterization. The concept of current and foreseeable land-use would also assist in providing a complete interpretation of assessment results, in Section 8.0. In our view, baseline environmental information required for site characterization should also clearly include the "...socio-economic environmenL," as a new Item 7. Page 16. para 2. The reasons for maximum impact to occur at an interim period of time could be mentioned (e,g., radioactive progeny build-up and decay, design life of engineered barriers, thermo-mechanical properties, etc.), Page 16, para 2. There may be a need to assess potential for inadvertent criticality which may be an issue for high level waste. Page 17. para 3. The first two lines are contradicting each other. Furthermore, does the CNSC advise relying on institutional controls beyond a few hundred years for on-ground mine and mill tailings? The document should give more consistent advice irrespective of the facility under consideration. Page 19, para 1. Microbiological effects and geochemical factors (such as colloidal transport) could also be relevant in the development of certain scenarios. Page 20, para 3. Why is the exposure to a direct intruder excluded (only inadvertent human intrusion is mentioned)? It may also be necessary to assess the facility safety in the post-intrusion phase (particularly if the intrusion goes undetected). Furthermore, lesser intrusions could also occur external to the facility, such as digging of wells in the surrounding areas, which may have radiological and environmental impacts. Page 22. para 4. It is stated, "complex models should not be used if there is insufficient data to support them". We feel that that this is a restrictive statement. There may be instances where complex models are required to support assessments and data may have to be generated to develop the models. Page 31. para 5. The definition of the term "institutional controls" is stated as, "The control of residual risks at a site after it has been decommissioned". Decommissioning is a term usually associated with a facility, not a site. Page 31. para 6. Why is the definition of "long-term" limited to radioactive waste disposal? The definition should encompass long-term storage as well. Given that institutional control can be expected to be available for a few hundred years or even longer for tailings management (as stated in the document), associating the definition of long term to the institutional control period may be inappropriate. Page 32. para 5. We would recommend the expansion of the definition of the term "receptor" to include "...human beings and their socio-economic and cultural circumstances...". The existing terms '...environmental entity... and... a population...' have in the past functioned to limit the analysis of impacts on people who may be affected. . ATTACHMENT 2 Report PSD-073-05 GLOSSARY OECD Organization for Economic Cooperation and Development IAEA International Atomic Energy Agency ALARA As Low As Reasonably Achievable CNSC Canadian Nuclear Safety Commission ICRP International Commission on Radiological Protection NSCA Nuclear Safety and Control Act NWMO Nuclear Waste Management Organization