ML23163A109

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Regulatory Guide Presentation for June 13 Public Meeting
ML23163A109
Person / Time
Issue date: 06/13/2023
From: Harriet Karagiannis, Matthew Learn, Janice Nguyen
NRC/NMSS/DFM/IOB, Storage and Transportation Licensing Branch
To:
References
Download: ML23163A109 (1)
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DRAFT REGULATORY GUIDE DG-3057 WEATHER-RELATED ADMINISTRATIVE CONTROLS AT INDEPENDENT SPENT FUEL STORAGE INSTALLATIONS Matthew Learn Senior Transportation and Storage Safety Inspector Inspection and Oversight Branch Division of Fuel Management, Office of Nuclear Material Safety and Safeguards Public Meeting: June 13, 2023

Todays Discussion

Purpose:

To inform the public about NRCs development of Draft Regulatory Guide (DG-3057), Weather-Related Administrative Controls at Independent Spent Fuel Storage Installations.

Desired Outcome: Ensuring the public understands (1) the main topics to be covered in the DG, (2) how comments can be submitted via the regulatory guidance process, and (3) the proposed schedule.

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Overview

  • The U.S. Nuclear Regulatory Commission (NRC) is considering issuing a new Regulatory Guide (RG) 3.77, Weather Related Administrative Controls at Independent Spent Fuel Storage Installations.
  • The RG will provide guidance to the industry on an additional option for complying with certain requirements for spent fuel storage licensees in 10 CFR Part 72.
  • Specifically, this new guidance would address 10 CFR 72.122(b) and 10 CFR 72.236(l) requirements and would provide an additional method that the NRC staff considers acceptable in certain limited situations for a licensee (specific or general) of an independent spent fuel storage installation (ISFSI) and certificate of compliance (CoC) holders to comply with protection against environmental conditions and natural phenomena.
  • On June 5, 2023, Draft Regulatory Guide 3057 was issued for public comment.

(ML23089A012) 3

Background

  • During NRC inspections, the NRC has identified that some ISFSI licensees had not performed the necessary evaluations to demonstrate that their site-specific parameters with respect to weather events, including wind and tornadoes, were enveloped by the design bases of the dry storage system (DSS) during outdoor DSS handling activities (ODHA).
  • Examples:
  • Heavy lift systems used for cask movement or transfer outdoors
  • Temporary removal of cask lids to facilitate loading outdoors 4

Regulatory Requirements CoC Holder Licensee 5

Background (Continued)

  • Provides guidance to NRC staff to exercise enforcement discretion when a licensee of an ISFSI does not comply with its design or licensing basis for protection against environmental conditions and natural phenomena as required by 10 CFR Part 72 when certain conditions are met by the licensee:
  • Develop procedures to establish administrative controls to mitigate tornado hazards during ODHAs
  • Document required weather checks prior to starting ODHAs
  • Document corrective actions necessary to restore compliance 6

NRC Review of NEI-22-02

  • On February 16, 2022, the Nuclear Energy Institute (NEI) submitted NEI 22-02, Guidelines for Weather-Related Administrative Controls for Short Duration Outdoor Dry Cask Storage Operations, Revision 0 for the staffs review. (ML22048A581)
  • Since the submittal, requests for supplemental information and observations were sent to NEI with a subsequent public meeting and clarification letter.
  • On November 4, 2022, NEI Submitted NEI 22-02, Revision 2.

(ML22339A035)

  • On December 14, 2022, the NRC informed NEI of their intent review NEI 22-02, Revision 2, to determine if it is generally acceptable for use in complying with the requirements in 10 CFR 72.122(b) and 72.236(l) through endorsement via a Regulatory Guide. (ML22339A180) 7

Regulatory Guide Objective

  • To provide the NRC staff and the industry guidance regarding methods of compliance, during limited situations using administrative controls to ensure that Structures, Systems, and Components (SSCs) important to safety (ITS) are designed to withstand weather-related phenomena without impairing safety performance of their intended design functions during ODHAs.
  • ODHAs are necessary at many sites to accomplish moving spent fuel from wet to dry storage and infrequently performed maintenance - performed as expeditiously where safety, personnel dose, and time are in an appropriate balance.
  • It may be performed within a single work shift but may take a maximum of 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />
  • This RG would endorse NEI 22-02, Revision 2, with clarifications and exceptions.

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Regulatory Guide Objective (Continued)

  • Administrative controls would include provisions to (1) preclude ODHAs during periods of actual adverse weather events or when adverse weather is predicted to occur, and (2) provide compensatory measures to place SSCs ITS in an analyzed condition, through engineering analysis, to maintain confinement of radioactive material during ODHAs.
  • Trusted source - U.S. National Weather Service (NWS)
  • NWS weather forecasting is recognized as being accurate and reliable in the windows of time associated with planning and carrying out ODHAs.
  • Due to the higher reliability of shorter-term weather forecasting, administrative controls can be relied upon to help ensure safety of 10 CFR Part 72 SSCs ITS when a transfer activity occurs.

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Clarifications and Exceptions

  • The RG will endorse NEI 22-02, Revision 2, with 8 clarifications or exceptions. The staff believe these are necessary to ensure adequate guidance to ensure safe operation and to meet industry needs.
  • 8 Proposed Clarifications / Exceptions
  • Scope - 1, 2
  • Regulatory - 3, 4, 5 (Interconnected)
  • Implementation - 6, 7, 8 10

Clarification 1

  • NEI 22-02, Section 2.1 Short Duration Outdoor DCS Activities
  • This guidance is applicable to short-duration DSS operations conducted outdoors that are necessary at many sites to accomplish moving spent nuclear fuel from wet to dry storage.
  • Clarification - ODHAs may also include DSS operations performed outdoors associated with infrequently performed maintenance and inspection of a DSS (e.g., aging management inspections).

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Exception 2

For SSC licensed under 10 CFR Part 50, the existing 10 CFR Part 50 licensing basis applies.

  • Lastly, this guidance also applies to GTCC or Class B/C waste casks that are identical to DSS shell structural and confinement designs to those of a 10 CFR Part 72 CoC that the cask is based upon.

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Clarification 3, 4, 5

  • Clarifications which are interconnected to ensure the guidance covers normal, off normal, and accident conditions required by 72.122 and 72.236.
  • Clarification 3 - RG applies to weather conditions associated with normal and off-normal winds as well as accident conditions.
  • Clarification 4 - Revised definition to Safe Condition and Forecast to include normal and off-normal conditions described in clarification 3.
  • Clarification 5 - Reinforces the licensee design control process and provides a process to determine an appropriate Safe Condition and Forecast described in clarification 4.

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Clarification 6

  • NEI 22-02, Section 3.1, Resources states in part that,
  • Licensees should use the NWSs hazardous weather outlook information unless another resource for the site is already used or can be justified as providing equivalent information in terms of timeliness and accuracy.
  • NRC Clarification - The staff are clarifying this statement to:
  • Licensees should use the NWSs information unless another resource can be justified as providing equivalent information in terms of timeliness and accuracy.

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Clarification 7

  • The licensee should determine the expected duration of short-duration outdoor activities by either benchmarking or dry runs. The ODHA duration should be periodically assessed based upon operating experience.

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Exception 8

  • NEI 22-02, Revision 2, states that, Malfunctions and unexpected delays during short duration outdoor activities can and do occur.

However, they are infrequent and the likelihood of a malfunction or delay occurring at the same time as the unexpected loss of a safe condition and forecast is so low, it should be considered non-credible.

  • Exception - Licensees should have procedures to ensure the DSS can be placed into an analyzed condition in the event of a malfunction or delay.

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Path Forward

  • Public comment period on DG-3057 ends July 05, 2023
  • Address public comments and finalize new RG 3.77
  • Publish final guidance (Fall 2023) 17

How to Submit Comments on DG-3057

  • Mail comments to: Office of Administration, Mail Stop: TWFN-7-A60M, U.S. Nuclear Regulatory Commission, Washington, DC 20555-0001, ATTN: Program Management, Announcements and Editing Staff.

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Contacts For any questions about the material in DG-3057, contact:

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