97-23696. Northern States Power Company, Prairie Island Nuclear Plant and Prairie Island Independent Spent Fuel Storage Installation, Issuance of Director's Decision Under 10 CFR 2.206  

  • [Federal Register Volume 62, Number 173 (Monday, September 8, 1997)]
    [Notices]
    [Pages 47227-47232]
    From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
    [FR Doc No: 97-23696]
    
    
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    NUCLEAR REGULATORY COMMISSION
    
    [Docket Nos. 50-282, 50-306 and 72-10]
    
    
    Northern States Power Company, Prairie Island Nuclear Plant and 
    Prairie Island Independent Spent Fuel Storage Installation, Issuance of 
    Director's Decision Under 10 CFR 2.206
    
        Notice is hereby given that the Director, Office of Nuclear Reactor 
    Regulation, has issued a Director's Decision concerning a Petition 
    dated May 28, 1997, filed by the Prairie Island Indian Community 
    (Petitioners) under Section 2.206 of Title 10 of the Code of Federal 
    Regulations (10 CFR 2.206). The Petition requested that the NRC (1) 
    determine that Northern States Power Company (the licensee) violated 
    the requirements of 10 CFR 72.122(l) by using its Materials License No. 
    SNM-2506 for an Independent Spent Fuel Storage Installation (ISFSI) 
    prior to establishing conditions for safely unloading the TN-40 dry 
    storage containers; (2) suspend Materials License No. SNM-2506 for 
    cause under 10 CFR 50.100 until such time as all significant issues in 
    the unloading process, as described in the Petition, have been 
    resolved, the unloading process has been demonstrated, and until an 
    independent third-party review of the TN-40 unloading procedure has 
    been conducted; (3) provide Petitioners an opportunity to participate 
    fully in the reviewing of the unloading procedure for the TN-40 cask, 
    hold hearings and allow Petitioners to participate fully in these and 
    any other procedures initiated in response to the Petition; and (4) 
    update the Technical Specifications for the Prairie Island ISFSI to 
    incorporate mandatory unloading procedure requirements.
        The Director of the Office of Nuclear Reactor Regulation has 
    determined that the Petition should be denied for the reasons stated in 
    the ``Director's Decision Under 10 CFR 2.206'' (DD-97-18), the complete 
    text of which follows this notice. The decision and documents cited in 
    the decision are available for public inspection and copying in the 
    Commission's Public Document Room, the Gelman Building, 2120 L Street, 
    NW., Washington, DC, and at the local public document room located at 
    the Minneapolis Public Library, Technology and Science Department, 300 
    Nicollet Mall, Minneapolis, MN.
        A copy of this decision has been filed with the Secretary of the 
    Commission for the Commission's review in accordance with 10 CFR 
    2.206(c). As provided therein, this decision will become the final 
    action of the Commission 25 days after issuance unless the Commission, 
    on its own motion, institutes a review of the decision within that 
    time.
    
        Dated at Rockville, Maryland, this 29th day of August 1997.
    
        For the Nuclear Regulatory Commission.
    Samuel J. Collins,
    Director, Office of Nuclear Reactor Regulation.
    
    Director's Decision Under 10 CFR 2.206
    
    I. Introduction
    
        On May 28, 1997, the Prairie Island Indian Community filed a 
    Petition pursuant to Section 2.206 of Title 10 of the Code of Federal 
    Regulations (10 CFR 2.206) requesting that the U.S. Nuclear Regulatory 
    Commission (NRC) take action to accomplish the following:
        1. Determine that Northern States Power (NSP) violated the 
    requirements of 10 CFR 72.122(l) by using its Materials License No. 
    SNM-2506 for an Independent Spent Fuel Storage Installation (ISFSI) 
    prior to establishing conditions for safely unloading the TN-40 dry 
    storage containers;
        2. Suspend Materials License No. SNM-2506 for cause under 10 CFR 
    50.100 until such time as all significant issues in the unloading 
    process, as described herein [the Petition], have been resolved, the 
    unloading process has been demonstrated, and until an independent 
    third-party review of the TN-40 unloading procedure has been conducted;
        3. Provide Petitioners an opportunity to participate fully in the 
    reviewing of the unloading procedure for the TN-40 cask, hold hearings 
    and allow Petitioners to participate fully in these and any other 
    procedures initiated in response to this Petition; and
        4. Update the Technical Specifications (TS) for the Prairie Island 
    ISFSI to incorporate mandatory unloading procedure requirements.
        The Petition has been referred to me pursuant to 10 CFR 2.206. The 
    NRC letter dated June 27, 1997, to Byron White, on behalf of the 
    Petitioners, acknowledged receipt of the Petition and provided the NRC 
    staff's determination that the Petition did not require immediate 
    action by the NRC. A notice of receipt was published in the Federal 
    Register on July 3, 1997 (62 FR 36085).
        On the basis of the NRC staff's evaluation of the issues and for 
    the reasons given below, the Petitioners' requests are denied.
    
    II. Background
    
        On October 19, 1993, the NRC issued Materials License No. SNM-2506 
    to NSP (the licensee) to allow storage of spent nuclear fuel in TN-40 
    dry storage casks, designed by Transnuclear Incorporated, at the ISFSI 
    located at the Prairie Island Nuclear Plant. No spent nuclear fuel was 
    allowed to be loaded into a storage cask at Prairie Island until 
    several preoperational license conditions were satisfied. Among the 
    preoperational license conditions were a required training exercise 
    (dry-run) of the loading, handling, and unloading activities for the 
    TN-40 casks and the implementation of written procedures describing the 
    actions to be taken during
    
    [[Page 47228]]
    
    operation, off-normal, and emergency conditions associated with the 
    Prairie Island ISFSI. The NRC issued TS defining operating limits, 
    surveillance requirements, design features, and administrative controls 
    as Appendix A to Materials License No. SNM-2506.
        A report dated April 20, 1995, submitted by the licensee to the NRC 
    pursuant to 10 CFR 72.82(e), provided the results of the preoperational 
    tests that were required to be performed by the licensee before loading 
    of spent fuel into a TN-40 cask. On May 11, 1995, the NRC granted a 
    schedular exemption to the provision of 10 CFR 72.82(e) that requires 
    licensees to submit the preoperational test results at least 30 days 
    before receipt of spent fuel into the ISFSI. The basis for the 
    exemption was the fact that the NRC staff had reviewed cask fabrication 
    records, observed portions of the preoperational test activities as 
    they occurred, and completed its review of the report submitted on 
    April 20, 1995. On May 12, 1995, the licensee began loading spent fuel 
    assemblies into a TN-40 cask. The licensee subsequently placed the 
    cask, and casks loaded since that time, onto the storage pad within the 
    Prairie Island ISFSI.
        NRC regulations include a requirement that an ISFSI be designed to 
    provide for the ready retrieval of spent fuel or high-level radioactive 
    waste for further processing or disposal. This regulation, 10 CFR 
    72.122(l), provides as follows:
    
        Retrievability. Storage systems must be designed to allow ready 
    retrieval of spent fuel or high-level radioactive waste for further 
    processing or disposal.
    
        Certain events or conditions could warrant removing a TN-40 cask 
    from the Prairie Island ISFSI and returning it to the spent fuel pool 
    and unloading the stored fuel assemblies. In addition to the regulatory 
    requirements in 10 CFR 72.122(l) pertaining to retrieval of the fuel 
    assemblies for further processing or disposal, the TS for the Prairie 
    Island ISFSI requires the licensee to take corrective actions in 
    response to those design-basis events or conditions that may challenge 
    the integrity of the storage cask or the cladding of the spent fuel 
    assemblies. For example, Section 2.3, ``Maximum Cask Lifting Height,'' 
    Section 3/4.3, ``Maximum Helium Leak Rate,'' and Section 3/4.5, 
    ``Maximum Cask Surface Temperature,'' of the TS include provisions for 
    unloading of a TN-40 storage cask in response to the specified events 
    or conditions.
        NRC regulations in 10 CFR Part 72 require that the design of the 
    storage system and the procedures implemented by specific licensees 
    support the unloading activity, whether it is being performed to allow 
    further processing or disposal of the spent fuel or it is required as 
    part of the response to an unplanned event or condition, while 
    preventing gross ruptures of the fuel cladding in order to prevent 
    operational safety problems. Unloading procedures should also include 
    contingencies in case fuel cladding has degraded during storage such 
    that additional measures are necessary to address increased 
    radiological hazards during the unloading process.
        NRC regulations, facility licenses, and NRC-approved quality 
    assurance programs require licensees to establish and maintain a formal 
    process for the preparation and issuance of procedures and changes 
    thereto. NRC assessments of licensee procedures are generally conducted 
    as part of the NRC's inspection program. In this instance, the major 
    procedures pertaining to dry cask storage activities at Prairie Island, 
    including the procedure for unloading a cask, were reviewed by the NRC 
    staff during a special inspection conducted from January 24 through May 
    11, 1995. In addition to the review of the licensee's facility and 
    procedures, the NRC inspectors observed preoperational testing that the 
    licensee was required to perform before loading casks with spent fuel 
    assemblies. The inspection findings are documented in NRC Inspection 
    Report 50-282/95002; 50-306/95002; 72-10/95002(DRP), dated June 30, 
    1995.
        The NRC inspectors identified several instances in which the 
    procedures for dry cask storage activities that the licensee had in 
    place at the beginning of the inspection, including the procedures for 
    loading and unloading of the TN-40 casks, did not ensure compliance 
    with the requirements of the license. Although the inspectors were able 
    to verify that the licensee corrected the identified procedural 
    deficiencies during the course of the inspection, a Notice of Violation 
    was issued to the licensee for failing to satisfy Criterion V of 
    Appendix B to 10 CFR Part 50, which for activities affecting quality, 
    requires the preparation and adherence to procedures appropriate to the 
    circumstances. In addition, the inspectors identified weaknesses in the 
    licensee's initial performance in overseeing the activities of the cask 
    vendor and in overall planning for dry cask storage activities. 
    However, on the basis of the licensing reviews and inspection findings, 
    documented in Inspection Report 50-282/95002; 50-306/95002; 72-10/
    95002(DRP), the NRC staff concluded that as of May 1995, the licensee 
    had corrected the identified deficiencies and was ready to safely load 
    and, if necessary, unload spent nuclear fuel in TN-40 casks.
        In July 1995, the NRC staff issued an action plan for dry cask 
    storage to manage the resolution of a variety of technical and process 
    issues that were identified during the licensing reviews and 
    inspections completed for the first several ISFSI facilities. An item 
    related to the loading and unloading of dry storage casks was added to 
    the action plan, in part to ensure that the importance of the unloading 
    procedures was emphasized to licensees and technical issues related to 
    unloading problems were resolved. Addition of an item pertaining to 
    unloading was deemed prudent because the staff observed that some 
    unloading procedures implemented by licensees neglected to consider 
    contingencies and assumptions related to possible fuel degradation, gas 
    sampling techniques, cask design issues, radiation protection 
    requirements, and the thermal-hydraulic behavior of a cask during the 
    process of cooling and filling it with water from the spent fuel pool.
        To implement the action plan, the NRC staff formed a working group 
    to identify issues associated with loading and unloading processes for 
    dry storage casks and to propose means of informing the industry and 
    the NRC staff of those issues. The working group considered industry 
    experiences, concerns identified during reviews and inspections, and 
    other issues related to loading and unloading procedures. The working 
    group completed its reviews in April 1996. The concerns related to 
    unloading procedures reviewed by the working group were found to 
    involve either (1) isolated occurrences that had been adequately 
    resolved by site-specific corrective actions or (2) generic issues that 
    were addressed by incorporating remedial measures into ongoing staff 
    activities, such as the preparation of revised inspection procedures or 
    other guidance documents.
        To fulfill some of the goals included in its dry cask storage 
    action plan, the NRC staff has emphasized the importance of unloading 
    procedures and shared observations with licensees using or considering 
    dry cask storage during opportunities such as the Spent Fuel Storage 
    and Transportation Workshop held in May 1996 and meetings with 
    individual licensees. The staff revised inspection procedures to 
    specifically instruct NRC inspectors to review unloading procedures 
    developed by licensees and to identify those issues that warrant 
    particular attention. Guidance included in NRC Inspection
    
    [[Page 47229]]
    
    Procedure 60855, ``Operation of an ISFSI,'' issued February 1, 1996, 
    states:
    
        For unloading activities, attention should be paid to how the 
    licensee has prepared to deal with the potential hazards associated 
    with that task. Some potential issues may include: the radiation 
    exposure associated with drawing and analyzing a sample of the 
    canister's potentially radioactive atmosphere; steam flashing and 
    pressure control as water is added to the hot canister; and 
    filtering or scrubbing the hot steam/gas mixture vented from the 
    canister, as it is filled with water.
    
        Similar guidance was included in NUREG-1536, ``Standard Review Plan 
    for Dry Cask Storage Systems,'' issued in January 1997. Application of 
    the revised guidance ensures that recent and future reviews will 
    address the adequacy of unloading procedures developed by licensees. 
    The staff also issued NRC Information Notice 97-51, ``Problems 
    Experienced with Loading and Unloading Spent Nuclear Fuel Storage and 
    Transportation Casks,'' dated July 11, 1997, to inform licensees of 
    operating experiences and problems encountered with the loading and 
    unloading of storage and transportation casks for spent nuclear fuel.
        To address those ISFSIs that began operation before the 
    improvements in the NRC's review and inspection guidance, the staff 
    performed audits or inspections of those licensee programs for which 
    the inspection record did not document whether the unloading procedures 
    adequately addressed the major issues included in the action plan. 
    Regarding Prairie Island, the staff reviewed the available information 
    and determined that additional reviews or inspections were not 
    necessary because the assessment of the unloading procedure performed 
    as part of the inspection documented in NRC Inspection Report 50-282/
    95002; 50-306/95002; 72-10/95002(DRP) adequately addressed the concerns 
    included in the NRC action plan.
    
    III. Discussion
    
        The Petition requests four actions by the NRC on the basis of the 
    contention that the unloading procedure implemented by the licensee was 
    inadequate and, therefore, the licensee violated the NRC regulation 
    requiring it to have the ability to readily retrieve spent fuel or 
    high-level radioactive waste for further processing or disposal.
    
    Item 1: Determine That the Licensee Violated 10 CFR 72.122(l)
    
        In support of the Petition's contention that the licensee violated 
    NRC requirements, the Petitioners claim that the procedure to unload a 
    TN-40 cask at Prairie Island has not been adequately evaluated or 
    tested because neither the NRC nor NSP has completely demonstrated that 
    a TN-40 dry cask can be unloaded after it has remained on the storage 
    pad for a number of years. The Petitioners state that their request is 
    supported by the fact that the preoperational test results for the 
    Prairie Island ISFSI were submitted to the NRC on the day before the 
    unloading procedure was approved by the licensee's Operations 
    Committee. The Petitioners also express concern that only portions of 
    the licensee's unloading procedure were tested during the required 
    preoperational tests and, therefore, the tests did not provide 
    assurance that an unloading can be done safely. In addition, the 
    Petitioners state that procedures for unloading a cask should address 
    specific concerns regarding failed fuel recovery and possible 
    contamination of the spent fuel pool, venting of radioactive gases, 
    functional checks of radiation monitoring and ventilation systems, and 
    the build-up of steam when water is pumped into the cask as part of the 
    unloading process.
        As previously mentioned, cask designs and associated procedures are 
    required to support the unloading of the spent fuel assemblies either 
    to support further processing or disposal or in response to an 
    unplanned event or condition that may challenge the integrity of the 
    storage cask or the cladding of the spent fuel assemblies. Although the 
    NRC staff agrees with the Petitioners' premise that actually unloading 
    a storage cask would likely result in licensees learning lessons that 
    could result in additional enhancements to unloading procedures, the 
    staff does not agree that an actual demonstration of the unloading 
    procedure at Prairie Island is warranted. In addition to the staff's 
    review of the procedure for unloading a TN-40 cask at Prairie Island, 
    reasonable assurance that the TN-40 casks can be safely unloaded is 
    provided by a variety of experiences related to the use and storage of 
    radioactive materials. These experiences include the dry-run exercises 
    that were performed to verify key aspects of unloading procedures for 
    the TN-40 cask; related research sponsored by the commercial nuclear 
    industry, the U.S. Department of Energy, and the NRC; actual loading 
    and unloading of transportation casks; loading of storage casks; 
    handling of spent fuel assemblies under various conditions; and 
    performing relevant maintenance and engineering activities associated 
    with reactor facilities.
        Regarding the Petitioners' concerns pertaining to the dates of the 
    submittal of preoperational tests and the approval of the licensee's 
    unloading procedure, the NRC staff identified this discrepancy in 
    Inspection Report 50-282/95002; 50-306/95002; 72-10/95002(DRP). The 
    administrative controls included in the TS for the Prairie Island ISFSI 
    require that the Operations Committee review and approve procedures and 
    changes thereto. The approval of the Operations Committee is usually 
    the last step in the process for preparing or revising a procedure. The 
    fact that the Operations Committee approved the procedure shortly after 
    submittal of the preoperational test results and before fuel loading 
    satisfied the preoperational license condition to implement written 
    procedures before loading spent nuclear fuel into a TN-40 cask. This 
    matter does not, therefore, represent a violation of NRC requirements 
    or introduce concerns pertaining to the technical adequacy of the 
    unloading procedure.
        The Petitioners identified several concerns pertaining to the lack 
    of specific guidance in the unloading procedure to address a scenario 
    in which significant fuel degradation occurs during storage. The NRC 
    staff agrees with the Petitioners that such a scenario would complicate 
    the unloading process by requiring additional measures and precautions 
    to limit the release of radioactive materials from the cask into parts 
    of the reactor facility and nearby environs. The licensee's unloading 
    procedure includes a step to sample the atmosphere within the cask 
    cavity to test for radioactive and flammable gases before venting the 
    cask cavity and loosening the bolts securing the cask lid. Following 
    the analysis of the gas sample, the licensee's unloading procedure 
    includes a hold point to allow personnel to determine whether 
    additional steps or precautions are warranted. While acknowledging many 
    of the Petitioners' legitimate concerns regarding the potential 
    difficulties in retrieving failed fuel from dry storage casks, the NRC 
    staff has concluded that licensees need not be required to incorporate 
    specific guidance into the normal unloading procedure to address this 
    unlikely situation. The staff's conclusion is based, in part, on the 
    fact that the required compensatory actions and precautions needed to 
    address such situations may vary significantly, depending on the actual 
    results from the analysis of the gas sample. Requiring the licensee to 
    include contingencies or steps in the unloading procedure to address 
    the unlikely event of failed fuel may unnecessarily complicate and 
    delay the unloading of fuel assemblies that
    
    [[Page 47230]]
    
    have remained intact during storage. On the basis of licensees' 
    experiences in developing and implementing plans to address the problem 
    of fuel assemblies damaged during reactor operations, in handling 
    radioactive wastes of various forms, and in resolving other comparable 
    problems, the NRC staff has confidence that licensees could, if 
    necessary, develop a plan to retrieve damaged fuel from a storage cask 
    while minimizing the radiological consequences to plant workers and the 
    general public. In addition to the general confidence of the NRC staff 
    that the technical problems associated with retrieving failed fuel 
    could be overcome, requirements for planning and executing such an 
    activity are contained in the licenses issued for the Prairie Island 
    ISFSI and the Prairie Island Nuclear Generating Plant, and NRC 
    regulations in 10 CFR Parts 20, 50, and 72. The NRC staff has, 
    therefore, accepted gas sampling and defined hold or decision points 
    before breaching the cask confinement boundary as an adequate means to 
    address concerns pertaining to the unlikely degradation of fuel 
    assemblies during storage.
        The specific issues raised by the Petitioners to support their 
    claim that the licensee's unloading procedure is deficient are 
    addressed below.
    (a) Failed Fuel Considerations
        As previously discussed, the NRC staff has accepted that procedures 
    developed by licensees to support unloading of dry storage casks do not 
    need to address the retrieval of failed fuel provided that measures to 
    detect possible fuel degradation and a defined hold point for 
    determination of possible compensatory actions are appropriately placed 
    within the subject procedures. As documented in NRC Inspection Report 
    50-282/95002; 50-306/95002; 72-10/95002(DRP), the licensee had 
    originally failed to incorporate a step in the unloading procedure for 
    taking a gaseous sample from the cask in order to ensure that fuel 
    degradation had not occurred during storage. However, in response to 
    the findings of the NRC inspectors, the licensee incorporated sampling 
    of the cask atmosphere and a hold point for deliberation into the 
    unloading procedure and the revised procedure was in place before spent 
    nuclear fuel was loaded into a TN-40 cask. The NRC staff has found that 
    this action, in combination with the requirement that spent fuel 
    assemblies loaded into TN-40 casks be free of gross cladding defects, 
    provides reasonable assurance that the licensee will not unknowingly 
    breach the confinement boundary of a cask containing failed fuel. In 
    the unlikely event that the gaseous sample indicates that spent fuel 
    assemblies have degraded during storage, the unloading procedure 
    instructs the licensee's Operations Committee to add steps or 
    precautions to the procedure in order to minimize the radiological 
    consequences of retrieving the failed fuel. The NRC staff has found 
    this approach to be acceptable and does not require the licensee's 
    normal unloading procedure to include contingency actions to address 
    the possible release of radioactive materials to parts of the reactor 
    facility, including the spent fuel pool, that may occur if fuel 
    assemblies degrade during storage. The NRC staff believes, however, 
    that the Petitioners have identified valid concerns regarding the 
    potential recovery of fuel assemblies that have unexpectedly degraded 
    during storage. As previously mentioned, the staff believes that the 
    regulations and licenses issued by the NRC require the licensee to 
    address these and other problems that may occur in the unlikely event 
    that fuel assemblies that have degraded during storage need to be 
    unloaded from dry storage casks.
    (b) Venting of Radioactive Gases
        The possible need to vent radioactive gases from a cask is among 
    the issues that the licensee would need to address if the required 
    sampling of the atmosphere within a cask indicates that the spent fuel 
    assemblies have experienced unanticipated degradation during storage. 
    As with the concern regarding the contamination of the spent fuel pool, 
    the need to vent the cask while minimizing the radiological 
    consequences of unloading a cask containing failed fuel is an issue 
    that the licensee would need to address before revising the procedure 
    and proceeding with the unloading process. In addition to ensuring that 
    the unloading activity results in occupational doses and doses to 
    members of the public that are as low as is reasonably achievable (see 
    10 CFR 20.1101), the licensee would need to perform the venting of a 
    cask containing failed fuel in accordance with the Prairie Island 
    Nuclear Generating Plant Facility Operating Licenses, associated TS, 
    and applicable regulations.
    (c) Radiation Monitors
        The Petitioners contend that the unloading procedure must include a 
    ``stop-check'' to verify that ventilation systems and radiation 
    monitors are functioning before the venting of a cask is performed. 
    Although agreeing with the Petitioners' general premise that 
    prerequisites to preforming procedures should include establishing 
    confidence in the tools and equipment being used, the NRC staff notes 
    that during the anticipated unloading of spent nuclear fuel that has 
    not degraded during storage, special ventilation or radiation 
    monitoring equipment beyond that specified in the licensee's unloading 
    procedure and radiation protection program is not required. The 
    unloading procedure requires the involvement of radiation protection 
    personnel and the activity must be controlled in accordance with the 
    licensee's radiation protection program, which includes provisions for 
    the maintenance and calibration of radiation detectors. Although the 
    venting process is not expected to need ventilation systems equipped 
    with filters and radiation monitors, the spent fuel pool special 
    ventilation system could be used if necessary. The spent fuel pool 
    special ventilation system is required to be operable during subsequent 
    steps in the procedure if spent fuel assemblies are being moved and the 
    system must be tested and maintained in accordance with the TS for the 
    Prairie Island Nuclear Generating Plant. In the unlikely event that the 
    licensee needs to unload a cask containing degraded fuel assemblies, 
    confirming the operability of those ventilation systems and additional 
    radiation monitoring equipment being used to minimize the release of 
    radioactive materials is an activity that the licensee would need to 
    address before revising the procedure and proceeding with the unloading 
    process.
    (d) Steam Build-up
        The Petitioners expressed concerns regarding the reaction of the 
    cask and stored fuel assemblies to the introduction of spent fuel pool 
    water during the execution of the unloading procedure. The unloading 
    procedure includes the partial immersion of the TN-40 cask into the 
    spent fuel pool, connection of hoses to the vent and drain connections, 
    and the slow introduction of spent fuel pool water to the cask cavity 
    and stored fuel assemblies. The procedure instructs personnel to 
    continuously monitor the temperature and pressure instrumentation 
    installed on the vent connection and to stop pumping water if the 
    pressure exceeds 10 psig or the temperature exceeds 240  deg.F. In the 
    staff's judgment, the cooling process imposed by these limitations on 
    temperatures and pressures at the vent port of the cask will adequately 
    ensure that the cooling of the cask and spent fuel is gradual and, 
    thereby, prevent safety problems that could hypothetically result from 
    damage to the
    
    [[Page 47231]]
    
    cask or the fuel assemblies because of stresses induced by a poorly 
    controlled addition of cooling water from the spent fuel pool.
        The Petitioners expressed concerns pertaining to the range of the 
    instrumentation used during the venting of a TN-40 cask and stated that 
    higher ranges for temperature and pressure are necessary. The 
    instrumentation ranges specified in the unloading procedure's drawing 
    of the cask vent port adapter are 50-300  deg.F for temperature and 0-
    30 psig for pressure. While not judging if these are the optimum ranges 
    for the instrumentation, the NRC staff finds that the ranges are 
    adequate to support the administrative limits of 240  deg.F and 10 psig 
    established in the procedure and the related response action of 
    stopping the addition of water to the cask if these administrative 
    limits are exceeded. Regarding the Petitioners' concern regarding the 
    need to post hazard warnings during the refilling of a cask, the 
    unloading procedure does include several notes and precautions to 
    remind personnel that the fluid exiting the vent port may present 
    radiological and thermal hazards.
        In summary, many of the Petitioners' concerns pertain to potential 
    problems with unloading spent fuel from a TN-40 cask if the fuel 
    cladding has degraded during storage. While acknowledging that such 
    concerns regarding the potential difficulties in retrieving failed fuel 
    from dry storage casks are legitimate, the NRC staff has concluded that 
    licensees need not be required to incorporate specific guidance into 
    the normal unloading procedure to address this unlikely situation. On 
    the basis of its review of the information provided by the Petitioners 
    and its reviews of the licensee's procedure for unloading TN-40 casks 
    at Prairie Island, the NRC staff has not identified violations of 10 
    CFR 72.122(l) or other regulatory requirements pertaining to the 
    content or quality of the licensee's unloading procedure.
    
    Item 2: Suspend Materials License No. SNM-2506
    
        On the basis of the contention that the licensee's unloading 
    procedure was inadequate, the Petitioners requested that Materials 
    License No. SNM-2506 be suspended until such time as the significant 
    issues in the unloading process have been resolved, the unloading 
    process has been demonstrated, and an independent third-party review of 
    the TN-40 unloading procedure has been conducted.1
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        \1\ The Petitioners request that Materials License No. SNM-2506 
    be suspended for cause in accordance with 10 CFR 50.100. Provisions 
    for the modification, revocation, or suspension of the licenses for 
    ISFSI facilities are contained in 10 CFR 72.60. The possible reasons 
    for suspending licenses for ISFSIs in accordance with 10 CFR 72.60 
    are similar to the corresponding reasons for suspending licenses for 
    production and utilization facilities in accordance with 10 CFR 
    50.100.
    ---------------------------------------------------------------------------
    
        As previously stated, the NRC staff has performed a review of the 
    procedure for unloading a TN-40 cask at Prairie Island. The review, 
    including verification that the licensee's unloading procedure was 
    revised to address deficiencies identified by the NRC inspectors, is 
    documented in NRC Inspection Report 50-282/95002; 50-306/95002; 72-10/
    95002(DRP). The review performed during the NRC inspection, subsequent 
    evaluations performed by the NRC staff as part of the activities 
    associated with the dry cask storage action plan and the review of this 
    Petition, and the required control of the procedure in accordance with 
    licensee programs developed in accordance with NRC regulations, 
    facility licenses, and NRC-approved quality assurance programs provide 
    reasonable confidence that the licensee could, if necessary, safely 
    unload a TN-40 cask.
        Regarding a third-party review, the NRC staff's concern about the 
    quality of licensees' unloading procedures led it to include the issue 
    in the dry cask storage action plan. The action plan provided a 
    framework for the identification and resolution of various technical 
    and administrative issues related to the use of dry storage casks. The 
    previously mentioned actions taken by the NRC staff and licensees 
    adequately resolved the identified issues pertaining to cask unloading 
    procedures. In the specific case of the unloading procedure at Prairie 
    Island, the licensee revised the procedure to address the problems 
    identified by the staff during its inspection. On the basis of the 
    actions it has already taken, the NRC staff does not believe that the 
    situation warrants additional review of the licensee's unloading 
    procedure by an independent third party.
    
    Item 3: Allow Petitioners to Review Procedure, and for NRC to Hold 
    Hearings and Allow Petitioners to Participate in the Proceedings
    
        The licensee has provided the NRC with the unloading procedure, 
    including Revision 2, dated November 8, 1996, for placement into the 
    public record, and the Petitioners have been supplied with or have 
    obtained copies of the procedure from the NRC's document control 
    system. Accordingly, Petitioners have had the opportunity to review a 
    recent revision of the unloading procedure. For the reasons previously 
    discussed in this decision, the NRC staff sees no reason to undertake 
    additional reviews of the procedure or to initiate a formal proceeding 
    in which the Petitioners could participate. Although the NRC has 
    decided not to initiate a hearing in response to this Petition, the 
    Petitioners are encouraged to continue their interactions with the NRC 
    staff regarding concerns or questions about the operation of the 
    Prairie Island Nuclear Generating Plant or the Prairie Island ISFSI.
    
    Item 4: Update the Technical Specifications for the Prairie Island 
    ISFSI to Incorporate Mandatory Unloading Procedure Requirements
    
        The TS for ISFSIs are required, by 10 CFR 72.44, to include 
    requirements in the following categories:
        (1) Functional and operating limits and monitoring instruments and 
    limiting control settings;
        (2) Limiting conditions;
        (3) Surveillance requirements;
        (4) Design features; and
        (5) Administrative controls.
        Although the TS for the Prairie Island ISFSI requires that TN-40 
    casks be unloaded if certain events or conditions defined in the TS are 
    satisfied, the TS do not include specific requirements for the 
    unloading process. The content of the TS for the Prairie Island ISFSI 
    is typical in this respect since neither 10 CFR 72.44 nor the 
    associated regulatory guidance documents specify that technical 
    specifications should include special requirements for the unloading 
    procedure.2 Instead, the functional and operating limits, 
    limiting conditions, administrative controls, and other requirements 
    included in the TS for the Prairie Island ISFSI are intended to 
    maintain the cask and stored spent fuel assemblies within the limits 
    established for safe operation during storage within the ISFSI and 
    activities such as loading and unloading of the casks. For example TS 
    2.3 limits the allowable lifting heights during movement of the cask
    
    [[Page 47232]]
    
    from the ISFSI and TS 3/4.2 requires a measurement of the boron 
    concentration of the water in the spent fuel pool before water is 
    introduced to the cask during the unloading process.
    ---------------------------------------------------------------------------
    
        \2\ Recent NRC staff guidance pertaining to the appropriate 
    content of technical specifications is provided in NUREG-1536, 
    ``Standard Review Plan for Dry Cask Storage Systems,'' published in 
    January 1997. Similar guidance is provided by NRC Regulatory Guide 
    3.61, ``Standard Format and Content for a Topical Safety Analysis 
    Report for a Spent Fuel Dry Storage Cask,'' issued in February 1989, 
    and NRC Regulatory Guide 3.48, ``Standard Format and Content for the 
    Safety Analysis Report for an Independent Spent Fuel Storage 
    Installation (Dry Storage),'' issued in October 1981.
    ---------------------------------------------------------------------------
    
        The absence of specific requirements in the TS to control the 
    unloading process does not diminish the importance that the NRC staff 
    places on this activity or the validity of the Petitioners' concerns. 
    The NRC staff believes that other regulatory requirements provide an 
    equivalent level of protection to the Petitioners' request to include 
    specific requirements in the TS to control the unloading of a TN-40 
    cask. The administrative controls in the TS for the Prairie Island 
    ISFSI require that the associated procedures, including the unloading 
    procedure, be prepared, reviewed, and maintained in accordance with the 
    requirements of the Prairie Island Nuclear Generating Plant Facility 
    Operating Licenses and associated TS. In addition, under existing NRC 
    requirements, the licensee must adequately implement procedures to 
    control loading, maintaining, and unloading of dry storage casks (see 
    10 CFR 72.122, 10 CFR 72.150, and 10 CFR 72.152). For example, the NRC 
    inspection documented in Inspection Report 50-282/95002; 50-306/95002; 
    72-10/95002(DRP) resulted in a Notice of Violation issued to the 
    licensee because the licensee failed to satisfy the NRC's requirements 
    in Criterion V of Appendix B to 10 CFR Part 50 by not having 
    incorporated appropriate steps and precautions into the original 
    procedure developed to control unloading of a TN-40 cask. As 
    demonstrated by the example, no changes to the TS or the Safety 
    Analysis Report (SAR) are needed to ensure that enforceable operating 
    controls and limits are in place to address the unloading of a cask.
        In regard to another concern raised by the Petitioners, the Prairie 
    Island ISFSI SAR and other docketed correspondence do state that 
    unloading a TN-40 cask would be performed using a procedure that is 
    basically the reverse of the procedure used to load the cask. Although 
    this statement, in a general sense, is true, the NRC staff agrees with 
    the Petitioners that such statements may be misleading in that they 
    oversimplify the description of the unloading activity. For this 
    reason, the NRC staff included an item related to unloading procedures 
    in its dry cask storage action plan to ensure that actual unloading 
    procedures did not reflect such an oversimplified representation. The 
    unloading procedure for the dry storage casks at Prairie Island was 
    inspected by the NRC staff and, as previously discussed, was ultimately 
    found to provide adequate guidance to control the unloading process.
    
    IV. Conclusion
    
        For the reasons described above, the NRC has determined that no 
    adequate basis exists for granting the Petitioners' request for 
    suspension of Northern States Power Company's license for dry cask 
    storage of spent nuclear fuel at Prairie Island or for taking the other 
    actions requested by the Petitioners. While acknowledging that the 
    Petitioners' concerns regarding the potential difficulties in 
    retrieving failed fuel from dry storage casks are legitimate, the NRC 
    staff has concluded that licensees need not be required to incorporate 
    specific guidance into the normal unloading procedure to address this 
    unlikely situation.
        A copy of this decision will be filed with the Secretary of the 
    Commission for the Commission to review in accordance with 10 CFR 
    2.206(c).
        As provided by this regulation, this decision will constitute the 
    final action of the Commission 25 days after issuance, unless the 
    Commission, on its own motion, institutes a review of the decision 
    within that time.
    
        Dated at Rockville, Maryland, this 29th day of August 1997.
    
        For the Nuclear Regulatory Commission.
    Samuel J. Collins,
    Director, Office of Nuclear Reactor Regulation.
    [FR Doc. 97-23696 Filed 9-5-97; 8:45 am]
    BILLING CODE 7690-01-P
    
    
    

Document Information

Published:
09/08/1997
Department:
Nuclear Regulatory Commission
Entry Type:
Notice
Document Number:
97-23696
Pages:
47227-47232 (6 pages)
Docket Numbers:
Docket Nos. 50-282, 50-306 and 72-10
PDF File:
97-23696.pdf