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The regulations will be directed towards:
Isolating radioactive wastes from man and his environment for time periods sufficient to protect public health and safety and to preserve environmental values, and
Reducing to as low as reasonably achievable levels: (1) the risk to the public health and safety, and (2) long-term social commitments such as land-use withdrawal, resource commitment, surveillance requirements, number of committed sites, etc.
Regulations in the area of high-level wastes will address:
1. Waste classification and high-level waste solids performance criteria—what wastes must be placed into a HLW repository and what form these wastes must be in;
2. Site suitability criteria—what constitutes an acceptable site for a repository;
3. Repository design criteria—what constraints must be placed on development and operation of a repository;
4. Repository licensing specifications—what mechanisms will be used to review proposed facilities to determine if they will meet the above regulations and will be safe.
In the case of solids performance criteria, site suitability criteria and repository design criteria, the criteria will indicate how the waste, the site and the repository should perform. The NRC staff is also developing methods to enable it to independently assess how a proposed site or design will act and whether the predicted actions will meet the minimum acceptable performance.
PERFORMANCE CRITERIA FOR SOLIDIFIED-HIGH-LEVEL REPROCESSING WASTES
For this effort, the NRC staff is using a systems analysis model which considers the various situations which could lead to potential release of radioactive materials during handling, storage, transportation, and disposal of high-level solid waste. A systems analysis approach will also be used to develop performance criteria for spent fuel to be disposed of in deep geological structures. Three mechanisms which control the release of radioactive materials have been identified: volatili. zation, dispersion of particulates, and leaching by water.
The performance criteria will be structured to require control of each of these mechanisms based on an analysis of the pathways each effects, the state of technology for controlling each mechanism, and balancing the cost of control against the benefits in terms of reduced risks to individuals and populations. Although the criteria will be derived from analytical pathway studies for various accident scenarios, the criteria will be set forth in terms of impact resistance, thermal stability, and chemical stability including resistance to leaching by water in order to facilitate the testing of potential candidate waste forms against the criteria.
The results obtained to date indicate that the pre-emplacement waste environs may be more limiting in establishing the solid waste performance criteria than the post-emplacement environs assuming waste emplacement in a stable geologic repository.
WASTE CLASSIFICATION Another of the programs under way is directed at classifying wastes according to the degree of confinement necessary to ensure containment of the wastes until they decay to some acceptable low-risk level. Criteria will be developed which specify which wastes:
1. Require isolation in a Federal repository—probably high-level reprocessing wastes, spent fuel, and transuranic contaminated waste;
2. Require confinement in a commercially operated waste disposal facility (i.e., shallow land burial)-probably reactor operating wastes, structural materials from reactor decommissioning and radioactive medical wastes; and
3. Can be dispersed to the environment.
The criteria will, among other things, specify the highest permissible transuranic content of wastes to be disposed of by shallow land burial and the means by which fuel hulls must be disposed. Together the waste classification criteria and the HLW solidification criteria will specify what must be placed in a repository and what form the waste must take.
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SITE SUITABILITY CRITERIA
Independent of DOE's site selection, NRC must develop criteria on which to judge whether a proposed site is suitable for a HLW repository. A proposed site would be suitable if it is capable of containing radionuclides for periods of time adequate to protect the public health and safety and is acceptable based on environmental (including socioeconomic) concerns. Development of these criteria began in August 1976 with the formation of an NRC Earth Sciences Task Force to identify areas which needed study and potential limiting conditions for siting a HLW repository. Subsequently, and with the aid of an NRC contractor, preliminary criteria (earth science criteria and other non-earth science acceptance criteria including geographic, demographic, and socioeconomic factors) were developed. Those criteria are now being evaluated and their impacts assessed.
A proposed regulation supported by a DEIS is scheduled to be published for comment in August 1978.
REPOSITORY DESIGN CRITERIA
The NRC staff is establishing general performance criteria for HLW repositories.
he criteria will lude such items as: Quality assurance measures for design and construction; requirements for protection against natural phenomena, performance requirements for containment barriers, compatibility between waste forms and containment media, nuclear safety requirements, physical protection requirements.
With regard to methods which will enable NRC to independently assess how a proposed site or design will act and whether the predicted actions will meet the minimum acceptable performance, we will use two analytical methods to predict and assess design performance: 1. Analytical/mathematical models (i.e., transport and systems analysis models) by which the elements of a proposal can be evaluated, and 2. Technical procedures which set forth factors to be considered by the staff in licensing evaluations and establishing boundary conditions for acceptability (e.g., standard review plans).
Additionally, NRC has two studies under way to identify acceptable risk for accidental releases from waste management operations. At this stage, the studies are directed at identifying methods that could be employed to quantify acceptable risk.
REPOSITORY LICENSING PROCEDURES
Within some specified repository licensing procedures, NRC will utilize all of the above described criteria and assessment tools to review a DOE repository application and to make a licensing decision as to whether the proposed repository is adequate to protect public health and safety and environmental quality. In developing licensing procedures, the NRC staff is considering both timeliness and public participation. The tentative repository licensing procedures may be divided, for discussion purposes, into three phases: preliminary site review, repository development and repository operation. The procedures have been developed using the present procedures for review of large fuel cycle materials licenses, such as fuel fabrication plants and uranium mills, as a point of departure.
The criteria in the regulation will be applicable to disposal of solidified high-level (including spent fuel) and transuranic wastes in any deep geologic medium within the confines of the continental United States. Assessment capability will only be applicable to disposal of solidified reprocessing wastes and low-level transuranic wastes in bedded salt. Work is now underway to expand this capability to other waste: types (e.g., spent fuel) and geologic media (bedded shales and basalt). However, this work is not expected to be completed until mid 1980.
PROGRAM RESPONSIBILITY Question. Within the Commission, how will this effort be managed and who is responsible for its execution and completion?
Ånswer. Within the Commission staff the major role for nuclear waste management lies in the Office of Nuclear Material Safety and Safeguards (N MSS). The licensing review of a high-level waste repository will be done by the NMSS staff, and that staff has the overall responsibility for preparation for that review. This preparation includes the development of the plan, the identification of additional support required of other organizations, the definition of needed standards and guides, and the development of the review procedures and analytical techniques needed for the actual license review.
Within NMSS is the Division of Fuel Cycle and Material Safety and within that Division is an Assistant Director for Waste Management and a staff devoted entirely to the area of waste management. This group provides a consistent overview of waste management activities on all licensed nuclear sites (upon request and in support of other parts of the Commission staff) and had as its licensing responsibility the long-term storage and disposal of any nuclear waste which is shipped off the site of its production.
While NMSS has the lead role for all aspects of preparing for licensing a highlevel waste repository, other offices also have important roles. In particular, the Office of Standards Development (OSD) will be assuming an increasingly important part of the effort during the next few years. As the needs for standards, regulations and guides are developed by the NMSS staff, OSD is asked to help prepare the needed documents. That office will then carry proposed regulation or guide through the formal review and rule making process.
Upon request from NMSS, the Office of Nuclear Regulatory Research (RES) has undertaken the development of new sophisticated analytical techniques and the development of specific bodies of important information useful to either the development of the standards or to the review of the license application.
Together, NMSS, OSD and RES carry out the major functions in preparing for licensing the repository. Other offices play important supportive roles as well. I submit for the record the following chart to show these offices. Special among these is the Office of Nuclear Reactor Regulation. It provides a group of technical specialists in geology, biology, and other disciplines who are important to our reviews.
In short, the licensing of high-level waste repositories is being managed in a manner similar to the licensing of any other major nuclear installation. The only clear difference is the need for special preparation arising from the fact that no such repository has ever been reviewed for licensing.