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Deep Geological Disposal Of Nuclear Waste Essay

, Research Paper

The General Problem The generation of energy from nuclear fuel reactors has been a highly controversial issue for the better part of the last century. At one point in the 1960’s, nuclear power was thought to be the energy source of the future because it was considered cleaner than carbon or coal, and much more efficient. After incidents such as the near fatal meltdown at Three Mile Island and the disastrous incident at Chernobyl, many people have been vehemently opposed to nuclear fuel generated power. Recently, in many parts of the world, people have run into other implications associated with the use of nuclear energy. Nuclear wastes have continued to build up and people have desperately been searching for some method of permanent disposal for these wastes. A great deal of nuclear fuel bundles are accumulating and above ground storage facilities continue to be filled. Currently in Canada, Ontario Hydro’s 20 reactors have produced 1 million used fuel bundles. These used fuel bundles are placed in Ontario Hydro’s wet storage facilities, where they are placed in above ground cement structures. Ontario only has enough wet storage to facilitate 1.5 million fuel bundles, and has predicted that these by the year 2025 (the end of the life of the reactors), 3.3 million spent fuel bundles will remain as waste to be disposed. The continually accumulating fuel bundles have prompted Atomic Energy of Canada (AECL) to search for a permanent method of disposal for these used fuel bundles. The idea of deep geological disposal began in Canada in 1977 with the Hare Report. This report stated that used fuel waste could not be allowed to “accumulate indefinitely in intern storage.” This report went on to indicate that geological disposal was likely the best disposal option for Canada to pursue. In 1988, both the House of Commons Standing Committees on Environment and Forestry and on Energy, Mines, and Resources agreed on the need for some form of permanent nuclear waste disposal. Atomic Energy of Canada Limited has developed a disposal concept that is currently under review by the Environmental Assessment Panel. AECL has proposed to seal containerized nuclear fuel waste 500 to 1000 metres into the Canadian Shield. AECL feels that “the combination of engineered and natural barriers would protect people without the need for institutional controls.” AECL’s “proposed approach to concept implementation is to proceed in stages” that meet principles such as “environmental protection, voluntarism, shared decision making, openness, and fairness.” They indicate that siting, the first phase of the project, cannot begin until the proposal is passed on the conceptual level. There has been a great deal of concern that the Panel’s terms of reference state that the site selection process cannot be examined until the concept is passed. It seems that by examining the disposal concept without having a particular site in mind that AECL may be “putting the cart before the horse”. Three areas of concern that will addressed regarding the evaluation of a generic disposal concept include political, social, and technical aspects. Specific Issues There are a number of concerns expressed with the proposal for a generic disposal concept. Many people feel that there are various social, economic, and environmental implications that will arise as a result of the proposed plan by AECL. Previous experience with siting large complex facilities in Canada, particularly those involved with the treatment and management of hazardous waste, has shown that the siting process is frequently much more complex than the design of an adequate facility. Many people believe that AECL has proposed a generic disposal concept for evaluation because the multi-millions of dollars spent on research would provide momentum for the siting process. There are a number of key conditions that people have addressed concerning the evaluation of the proposal on the conceptual level. Many people have argued that technical, social, and economic issues of siting a facility in a remote area, near a northern community, or near a developed and industrialized area should be addressed prior to accepting the disposal concept. By examining the disposal on a conceptual level, it would appear that AECL feels that the technical aspects are more important than social aspects. There has also been concern expressed about the equity of the siting process. Concern has been raised by people from remote northern villages, as well as aboriginal communities, as to the equatability of the siting process. The eventual siting of a facility would not only affect the community where it is located, but will also have impacts on communities located along the transportation routes. The issue of transportation involves a number of questions about health and safety. AECL will need to consult with all stakeholders, especially those living along transportation routes to ensure that they accept the site selection. Also, a number of questions have been raised about the types of transportation that will be used, as well as past safety records with the transport of hazardous materials. If a remote site was chosen, there may not be an appropriate transportation route to get to the facility. Roads built to access remote facilities may also have large environmental impacts. If it is decided that the disposal concept is safe and acceptable, the Panel has devised terms of reference for advising governments on a future site selection process. In their Environmental Impact Statement, AECL has outlined a number of principles that they feel are necessary to be used in the site selection process. These principles include a commitment to safety and environmental protection, voluntarism, shared decision making, openness, and fairness. The completeness of AECL’s list of principles for site has been questioned by many critics. Also, the role of communities potentially affected by the host community has been questioned. It is evident that there are a number of concerns that will need to be addressed if and when the disposal concept is accepted by the Panel. It appears that by forwarding a generic disposal concept, AECL is putting a higher value on the technical aspects of high level waste disposal than social and economic concerns. Perhaps AECL should be looking at a site specific disposal concept as there are already a large number of issues that they will have to address if the disposal concept gets passed. There are a number of key issues that need to be addressed regarding the problems with evaluating the proposal for burial on the conceptual level. The transcripts of the high level nuclear waste hearings, made available from the Canadian Environmental Assessment Agency, provide some excellent examples of the problems with evaluation on the conceptual level. Public speakers such as Mrs. Ella de Quehen have presented these key issues to the Panel regarding the credibility of AECL’s proposal to develop on a conceptual level. It is clear that the AECL’s generic disposal concept has been plagued with political, social, and technical issues. Process In her presentation to the Panel, Mrs. Ella de Quehen points out a few of the political issues that have been questioned during the disposal hearings. de Quehen, a member of Northumberland Environmental Protection, points out that evaluating the proposal for high level nuclear waste burial on a conceptual level involves too much risk. de Quehen feels that it is difficult to select an acceptable level of health and safety risk from a project with unknown dimensions of geological, chemical, physical properties, and biophysical impacts. She also questions the meaning of the term “predicted effect”. In science, predictions are based on real data, not through computer generated models, something that AECL has made extensive use of. de Quehen feels that AECL has not actually used relevant data, and therefore cannot claim that “there are no predicted effects” of deep geologic burial. A second valid point that de Quehen raises in her presentation to the review panel is the fact that AECL has not succeeded in their attempt to model a generic post-closure assessment because they cannot get relevant data to address the uncertainty of burial in rock. It is extremely difficult to predict what will happen to rock formations that are highly dynamic in nature. Also, it must be taken into consideration that nuclear material remains reactive for many thousands of years and that many properties of the area of burial will change with time. This leads one to wonder why an inaccessible, generic assessment over such a long period of time would be attempted.

A third valuable point that Mrs. de Quehen raises in her presentation to the Panel is the fact that the Scientific Review Group (SRG) has accepted AECL’s inclination to design the proposal on a conceptual level, even though they feel that it is flawed. de Quehen points out that one would expect the SRG to determine that the post-closure generic assessment has failed, but they do not. de Quehen feels that the SRG has not produced substantial evidence that the generic disposal concept is acceptable, but that this is ok, because the nuclear lobby feels that a disposal system can be designed to meet expectations. She questions spending $400 million to research a generic proposal when the SRG would likely have given the project the go-ahead regardless of the quality of the impact statement submitted. It seems that the SRG has a clear conflict of interest with AECL. A final flaw that de Quehen points out with the acceptance of the generic proposal deals with the Atomic Energy Control Board (AECB). AECB has wrote a two part response document to AECL’s proposal for a generic assessment. Within the second part of the response document, AECB indicated that they felt that “the EIS has not adequately demonstrated the safety and feasibility of deep geological disposal for nuclear waste.” In the first part of the document, AECB contradicts the claims made in the second section by “recommending that the siting proceed.” The whole purpose of an environmental impact assessment is to mitigate a project’s environmental impacts and to provide a fair hearing away from industry lobbying and strong economic interests. AECB and AECL seem to have lost sight of the initial purposes of the impact assessment process. Standards A second aspect of the generic disposal concept that is troublesome is the issue of standards. It must be recognized that standards are very important in environmental assessment procedures to ensure that levels of environmental health and safety are maintained. Standards are one area where AECL’s generic disposal concept does no fare well. In their presentation to the Panel, Dr. Raymond Price and Dr. J. Archibald, members of the SRG, reveal that there are a number of standards that the pre-closure and post-closure generic conceptual models fail to meet. The objectives of the pre-closure assessment are to identify any possible safety implications or environmental affects of pre-closure activities. Other objectives are to identify measures that could be used to reduce environmental impacts, to assess the significance of environmental impacts, and to assess possible methods that could be used in transportation and disposal at the site specific phase. Price and Archibald note that the pre-closure assessment done by AECL does not meet the requirements need for an Environmental Impact Statement. The fact that the risk assessment modelling process is only based on artificially generated data means that it does not meet the current standards for “a major nuclear waste disposal facility with impacts as significant as a nuclear power plant.” The Canadian Standards Association (CSA) requires that facilities of this nature address any potential health impacts on workers and non-workers. The assessment done by AECL did not address the risk of cancer and serious genetic diseases for the general public, and therefore the risk assessment modelling process should not have been allowed to be implemented. As far as the requirements of an Environmental Impact Statement, the statement submitted by AECL had several blatant shortcomings. The potential impact on aboriginal peoples and their environment, which should have been combined with post-closure assessment, was not. Furthermore, the issue of transportation to and from the waste site should have been supported by case studies and a detailed analysis of realistic scenarios. Hydrogeology A third major concern with the generic disposal concept involves technical issues associated with the hydrogeology of the Shield. Despite the intensive computer modelling, there still remains a great deal of uncertainty surrounding the issue of hydrogeology. After a review of two case studies on the hydrogeology of the disposal concept, Dr. McCreath in his presentation to the Panel, questions the uncertainty associated with the study findings. McCreath is concerned about the clear contradiction that is evident in AECL’s case studies. Within the case study, AECL reveals that their disposal concept is fine in principle, but then go on to indicate that “the post-closure performance assessment is unsatisfactory” In his presentation, McCreath went on to list AECL’s case studies dealing with hydrogeology for post-closure assessment were “unsatisfactory”. If the disposal concept gets passed, there are no second chances. AECL has to be sure about issues such as hydrogeology before any wastes are deposited. If AECL found several potential sites and collected read data on issues such as hydrogeology, it would give people a little more confidence into technical research. In his presentation to the Panel, More Mrtazavi, a consulting engineer, indicated the need to address a site when modelling the hydrogeology of the Canadian Shield. Mortazavi concedes that the disposal concept can be used as a tool to help in the design of the project. However, he feels that “we should address the site – the potential of all various conditions of the Canadian Shield as a hydrogeological barrier that can be encountered, and then compare the tool that has been presented by AECL to see whether that tool is capable enough to handle those conditions with respect to robustness, safety, applicability, and social acceptance.” Conclusions It is clear that the burial of nuclear wastes is an issue that has many serious ramifications and implications. The siting of a nuclear waste repository would have a number of serious impacts on a large number of people. It is unfortunate that AECL’s current proposal for deep geological disposal is at the conceptual level. It is extremely difficult to evaluate a project that is hypothetical in nature and not site specific. A number of flaws in AECL’s proposal have been exposed at the nuclear hearings. Mrs. Ella de Quehen points out that the process has become very political in nature, involving a high degree of bureaucracy. Concerned about the almost complete dependance on computer modelling, de Quehen questions the limits of technology. Dr. Price and Dr. Archibald point out that the disposal concept should not be considered acceptable from a social point of view. The concept does not meet any standards and this puts the health and safety of all Canadians at risk. Dr. McCreath and Mori Mortazavi question the technical aspects associated with the hydro-geosphere and computer modelling. It is apparent that there are many flaws and uncertainties associated with the disposal concept. AECL should reconsider their generic proposal and look at other possible alternatives. By setting narrow terms of reference, AECL has limited itself in both options and capabilities. We can only hope that AECL will consider public view points and not do anything with nuclear wastes until a socially acceptable plan and guideline is found. If an acceptable plan for dealing with the wastes cannot be found, perhaps the best solution would be to consider monitoring the wastes above ground in a storage facility that is acceptable. Although AECL has been looked at as a leader in projecting new technologies in waste disposal, it must be realized that any project associated with the disposal of nuclear wastes would face a great deal of criticism. However, it this criticism that will force the public to realize faults with proposals such as these, consider alternatives, help protect the environment and humanity, and force people to think about the long term consequences of their actions.




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