Graded Approach to Dry Storage Cask and ISFSI Licensing

Graded Approach to Dry Storage Cask and ISFSI Licensing

Brian Gutherman for the Nuclear Energy Institute

October 28, 2016 • Rockville, MD

Overview

• RIRP I-16-01 purpose: Document NRC/Industry agreement that the Part 72 regulatory framework would benefit from implementation of a graded approach to better focus resources on nuclear safety and provide a plan to accomplish this

- Part 72 licenses and CoCs currently contain a level of detail not commensurate with the associated risk

- Currently there is little guidance governing what information is included in the licenses and CoCs

- NRC’s inspection program should have a bigger role

CoC Content

• Unnecessary CoC content is costly - CoC amendments and revisions – both number and

scope • Preparation (CoC holder)

• Review fees (CoC holder)

• Implementation (Licensee)

- Fuel selection package complexity

- 72.212 Report complexity, revisions • Every applicable CoC requirement needs to be addressed in

the site 72.212 Report

• Requirements invoking other rules seem innocuous, but are not; each one needs to be addressed in the 212 Report

Precedents

• Industry submitted a petition for rulemaking in 2012 in an effort to codify improvements to the Part 72 licensing framework (PRM 72-7)

- Founded on 1993 NRC policy statement on Improved Technical Specifications (ITS) for power reactors

- ITS successfully sharpened power reactor safety focus

- The fundamental principles of the policy statement transcend just power reactors

Part 50 Improved Tech Spec History

• From the NRC’s 1993 Policy Statement on Improved Technical Specifications (ITS):

Part 50 ITS History (cont’d) • Further from the ITS Policy Statement:

RIRP Problem Statement

• NRC and Industry agree • Industry believes we can use the work done in support of

the PRM to establish the graded approach

Graded Approach to Part 72 Regulatory Framework

• PRM 72-7 provides a strong foundation on which development of a graded approach to improving the license framework and having the correct information in the licenses and CoCs can be built - Includes selection criteria which should be applied

• Documenting a split of important-to-safety (ITS) and not-important-to-safety (NITS) structures, systems, and components (SSCs) is not the right place to start

• Consistent with NRC Part 50 policy and practice, content of dry storage licenses and CoCs should be based on SSC function, not safety classification

Graded Approach to Part 72 Regulatory Framework

• SSCs included in operating plant TS are based on the detection, initial conditions, and mitigation of design basis accidents described in the SAR, plus risk significant items

• PRM 72-7 describes selection criteria based on these principles, modified appropriately for casks

- Accident mitigation excluded based on passive design

- Additional, unique criteria proposed for cask contents

Graded Approach to Part 72 Regulatory Framework

• In addition to accident-related SSC function, control of the SSC should relate to “immediate concern to the health and safety of the public” - i.e., protection of the fission product

boundaries • Confinement boundary

• Fuel cladding

Proposed SSC Selection Criteria

• Criterion S1: Installed instrumentation that is used to detect, and indicate a significant abnormal degradation of the cask confinement boundary;

• Criterion S2: An initial condition of a design basis accident that either assumes the failure of or presents a challenge to the integrity of a fission product barrier;

• Criterion S3: A structure, system, or component which operating experience or risk considerations have been shown to be significant to public health and safety.

Proposed Approved Contents Selection Criteria

• Criterion C1: The characteristic or parameter is identified in 10 CFR 72.236(a);

• Criterion C2: A characteristic or parameter for which verification is a necessary condition to provide reasonable assurance that the cask safety functions of confinement, sub-criticality, and shielding will be performed;

• Criterion C3: A characteristic or parameter which operating experience or risk considerations have been shown to be significant to ensure public health and safety.

SSC Example

• SSC in a CoC not meeting proposed SSC selection criteria - Standardized NUHOMS®, Attachment A, TS 5.3.3 - TC Alignment with HSM or HSM-H

• Includes a +/- 1/8-inch tolerance for alignment during DSC transfer to and from the HSM

• Not used to detect confinement boundary degradation • Not an initial condition for a DBA • Not risk-significant for storage operations or retrievability

- TC alignment is an operational parameter that should be managed by the licensee and available for adjustment under 72.48, if needed

Contents Example

• Contents in a CoC not meeting proposed SSC selection criteria - HI-STORM 100, Appendix B, TS 2.4 - Individual fuel storage locations have limits on decay

heat - With individual fuel assembly limits on burnup and

cooling time, heat load is already defined - Non-fuel hardware also has burnup and cooling time

limits - Maximum heat load for the cask is what 72.236(a)

specifies, not individual fuel assembly

Other Issues of Concern

• Repeating Regulations in the CoC

• Items subject to QA program requirements

• Items governed by other programs

Example of CoC Content Repeating Regulations

• CoC 1004, Amendment 13, Attachment A, Section 5.2.4.a:

Repeating Regulations Example (cont’d)

• Because they are part of the CoC, licensees must separately address both of these requirements in the 72.212 Report

- Analyses to demonstrate compliance with 72.104 are already required and documented in the 212 Report

- Part 20 is not a regulation for which compliance is demonstrated by analysis – it’s performance-based

- Additional, site-specific dose assessments for these events by general licensees are contrary to the GL concept

Examples of Other Issues

• QA program scope

- Neutron absorber manufacturing and testing

- Canister helium leak testing

- ASME Code compliance/alternatives

• Training

• Radiation protection/ALARA

Industry Summary of Graded Approach

• Based on design functions as described in the ISFSI or cask FSAR, SSCs should be evaluated for inclusion in the CoC/TS against the “S” criteria, irrespective of ITS classification

• Approved contents’ characteristics or parameters should be evaluated for inclusion in the CoC/TS against the “C” criteria, irrespective of ITS classification

• Other license and CoC requirements should be governed by the regulations and licensee programs

Industry Proposed Changes to RIRP Screen

Industry Proposed Changes to Action Plan

Industry-Proposed Changes to Action Plan

Path Forward

• Finalize RIRP documents

• Industry and NRC discuss and refine selection criteria given what we have learned since PRM submittal

• Agree upon appropriate selection criteria

• Use the pilot CoC amendment to test implementation of the selection criteria

• Modify selection criteria per lessons learned from the pilot

• Develop industry guidance for NRC endorsement

QUESTIONS?