Guidance for Closure of Activities Related to Recommendation 2.1, Flooding Hazard Reevaluation

AGENCY:

Nuclear Regulatory Commission.

ACTION:

Draft interim staff guidance; request for comment.

SUMMARY:

The U.S. Nuclear Regulatory Commission (NRC) is soliciting public comment on its draft Japan Lessons-Learned Division Interim Staff Guidance (JLD-ISG), JLD-ISG-2016-01, “Guidance for Activities Related to Near-Term Task Force Recommendation 2.1, Flooding Hazard Reevaluation; Focused Evaluation and Integrated Assessment.” This draft JLD-ISG revision provides guidance and clarification to assist operating power reactor respondents and holders of construction permits under the NRC's regulations with the performance of the focused evaluations and revised integrated assessments for external flooding.

DATES:

Submit comments by May 23, 2016. Comments received after this date will be considered if it is practical to do so, but the Commission is able to ensure consideration only for comments received on or before this date.

ADDRESSES:

You may submit comments by any of the following methods (unless this document describes a different method for submitting comments on a specific subject):

• Federal Rulemaking Web site: Go to http://www.regulations.gov and search for Docket ID NRC-2016-0084. Address questions about NRC dockets to Carol Gallagher; telephone: 301-415-3463; email: Carol.Gallagher@nrc.gov. For technical questions, contact the individual listed in the FOR FURTHER INFORMATION CONTACT section of this document.
• Mail comments to: Cindy Bladey, Office of Administration, Mail Stop: OWFN-12-H08, U.S. Nuclear Regulatory Commission, Washington, DC 20555-0001.

For additional direction on obtaining information and submitting comments, see “Obtaining Information and Submitting Comments” in the SUPPLEMENTARY INFORMATION section of this document.

FOR FURTHER INFORMATION CONTACT:

Eric Bowman, Office of Nuclear Reactor Regulation, U.S. Nuclear Regulatory Commission, Washington, DC 20555-0001; telephone: 301-415-2963; email: Eric.Bowman@nrc.gov.

SUPPLEMENTARY INFORMATION:

I. Obtaining Information and Submitting Comments

A. Obtaining Information

Please refer to Docket ID NRC-2016-0084 when contacting the NRC about the availability of information for this action. You may obtain publicly-available information related to this action by any of the following methods:

• Federal Rulemaking Web site: Go to http://www.regulations.gov and search for Docket ID NRC-2016-0084.
• NRC's Agencywide Documents Access and Management System (ADAMS): You may obtain publicly-available documents online in the ADAMS Public Documents collection at http://www.nrc.gov/reading-rm/adams.html. To begin the search, select “ADAMS Public Documents” and then select “Begin Web-based ADAMS Search.” For problems with ADAMS, please contact the NRC's Public Document Room (PDR) reference staff at 1-800-397-4209, 301-415-4737, or by email to pdr.resource@nrc.gov. The ADAMS accession number for each document referenced (if it is available in ADAMS) is provided the first time that it is mentioned in the SUPPLEMENTARY INFORMATION section. For the convenience of the reader, the ADAMS accession numbers for obtaining materials referenced in this document are provided in a table in the section of this notice entitled, Availability of Documents.
• NRC's PDR: You may examine and purchase copies of public documents at the NRC's PDR, Room O1-F21, One White Flint North, 11555 Rockville Pike, Rockville, Maryland 20852.

B. Submitting Comments

Please include Docket ID NRC-2016-0084 in your comment submission.

The NRC cautions you not to include identifying or contact information that you do not want to be publicly disclosed in your comment submission. The NRC posts all comment submissions at http://www.regulations.gov as well as entering the comment submissions into ADAMS. The NRC does not routinely edit comment submissions to remove identifying or contact information.

If you are requesting or aggregating comments from other persons for submission to the NRC, then you should inform those persons not to include identifying or contact information that they do not want to be publicly disclosed in their comment submission. Your request should state that the NRC does not routinely edit comment submissions to remove such information before making the comment submissions available to the public or entering the comment submissions into ADAMS.

II. Background

Following the events at the Fukushima Dai-ichi nuclear power plant on March 11, 2011, the NRC established a senior-level agency task force referred to as the Near-Term Task Force (NTTF). The NTTF was tasked with conducting a systematic and methodical review of the NRC regulations and processes, and determining if the agency should make additional improvements to these programs in light of the events at Fukushima Dai-ichi. As a result of this review, the NTTF developed a comprehensive set of recommendations, documented in SECY-11-0093, “Recommendations for Enhancing Reactor Safety in the 21st Century, the Near-Term Task Force Review of Insights from the Fukushima Dai-ichi Accident,” dated July 12, 2011. These recommendations were enhanced by the NRC staff following interactions with stakeholders. Documentation of the staff's efforts is contained in SECY-11-0124, dated September 9, 2011, and SECY-11-0137, dated October 3, 2011.

As directed by the Commission's SRM for SECY-11-0093, the NRC staff reviewed the NTTF recommendations within the context of the NRC's existing regulatory framework and considered the various regulatory vehicles available to the NRC to implement the recommendations. In SECY-11-0124 and SECY-11-0137, the staff established the prioritization of the recommendations. After receiving the Commission's direction in SRM-SECY-11-0124 and SRM-SECY-11-0137, the NRC staff issued a request for information pursuant to section 50.54(f) of title 10 of the Code of Federal Regulations (10 CFR), “Conditions of licenses,” on March 12, 2012, requesting licensees to reevaluate the seismic and flooding hazards at their sites using updated hazard information and current regulatory guidance and methodologies. For plants where the reevaluated hazard exceeds the plant's design basis, the licensee was to conduct an integrated assessment. The information gathering is considered to be Phase 1 and was requested to support Phase 2 decision-making and determine whether available or planned measures provide sufficient protection and mitigation capabilities or if further regulatory action should be pursued in the areas of seismic and flooding design, and emergency preparedness.

In COMSECY-14-0037, dated November 21, 2014, the NRC staff requested that the Commission review and approve changes to revise the Recommendation 2.1 flooding assessments and integrate the Phase 2 decision-making into the development and implementation of mitigating strategies in accordance with Order EA-12-049 and the related Mitigation of Beyond-Design-Basis Events rulemaking.

In SRM-COMSECY-14-0037, the Commission disapproved this recommendation. Instead, the Commission instructed the staff to develop a closure plan for the flooding reevaluation activities and to reassess the existing guidance for performing a Phase 1 integrated assessment in order to focus on those plants with the most potential for safety benefits.

In COMSECY-15-0019, the staff provided revised guidance for performing a Phase 1 integrated assessment and described a modified process for identifying the list of plants that would be required to perform an integrated assessment. The process proposed by the staff included the development of a graded, risk-informed and performance-based approach consistent with Commission direction to focus on those plants with the greatest potential need for safety enhancements. Specifically, the process included consideration and evaluation of local intense precipitation by performing a focused evaluation of the impact of the hazard and implementing any necessary programmatic, procedural, or plant modifications to address the hazard, taking into account available warning time. The process also considered flood protection and available physical margin, where licensees will confirm the capability of existing flood protection to address the hazard exceedance by performing a focused evaluation. For licensees where the reevaluated hazard cannot be addressed via existing or planned flood protection, the process also includes the performance of an integrated assessment, using revised guidance, in order to conduct more detailed evaluations of plant response capability. This revised integrated assessment will capture, among other information, quantitative characteristics about the reliability of various aspects of plant response (e.g., reliability of equipment and manual actions), and risk insights with a focus on cliff-edge effects. The results will be used by the NRC to determine whether additional regulatory action, such as a plant-specific backfit, are warranted.

In SRM-COMSECY-15-0019, the Commission approved the staff's plans to modify the approach for integrated assessments to implement a graded approach for determining the need for, and prioritization and scope of, plant-specific integrated assessments. As discussed in COMSECY-15-0019, the majority of sites with reevaluated flooding hazards exceeding the design-basis flood are expected to screen out from the integrated assessment process. The licensees will instead provide focused evaluations to ensure appropriate actions are taken and that these actions are effective and reasonable.

The Nuclear Energy Institute (NEI) submitted guidance NEI 16-05, “External Flooding Assessment Guidelines,” Revision 0, on April 12, 2016. The guidance is an industry-developed methodology that describes the flooding impact assessment process, which is intended to meet the requested information of an integrated assessment, as described in the document titled, “Request for Information Pursuant to Title 10 of the Code of Federal Regulations (10 CFR) 50.54(f) Regarding Recommendations 2.1, 2.3, and 9.3, of the Near-Term Task Force Review of Insights from the Fukushima Dai-ichi Accident,” and to incorporate the changes described in COMSECY-15-0019.

Draft ISG JLD ISG 2016-01 is being issued to describe to stakeholders methods acceptable to the staff for performance of the focused evaluations and revised integrated assessments and describe some exceptions and clarifications to NEI 16-05, Revision 0.

This guidance is not intended for use in design-basis applications or in regulatory activities beyond the scope of performing the focused evaluations and integrated assessment part of NTTF Recommendation 2.1 flooding activities. This ISG is being issued in draft form for public comment to involve the public in development of the implementation guidance. Compliance with the ISG is not required.

III. Availability of Documents

The documents identified in the following table are available to interested persons through one or more of the following methods, as indicated.

The NRC may post materials related to this document, including public comments, on the Federal rulemaking Web site at http://www.regulations.gov under Docket ID NRC-2016-0084. The Federal rulemaking Web site allows you to receive alerts when changes or additions occur in a docket folder. To subscribe: (1) Navigate to the docket folder (NRC-2016-0084); (2) click the “Sign up for Email Alerts” link; and (3) enter your email address and select how frequently you would like to receive emails (daily, weekly, or monthly).

Proposed Action

By this action, the NRC is requesting public comments on draft ISG JLD-ISG-2016-01. This draft JLD-ISG proposes guidance related to the performance of a focused evaluation and integrated assessment as part of NTTF 2.1 flooding activities. The NRC staff will make a final determination regarding issuance of the JLD-ISG after it considers any public comments received in response to this request.