80 FR 21658 - Alternate Risk-Informed Approach for Addressing the Effects of Debris on Post-Accident Long-Term Core Cooling

NUCLEAR REGULATORY COMMISSION

Federal Register Volume 80, Issue 75 (April 20, 2015)

The U.S. Nuclear Regulatory Commission (NRC) is issuing for public comment draft regulatory guide (DG), DG-1322, ``Alternate Risk- Informed Approach for Addressing the Effects of Debris On Post-Accident Long-Term Core Cooling.'' This DG proposes new guidance that describes methods and procedures that the NRC staff considers acceptable for complying with a voluntary, risk-informed alternative in a proposed revision of the NRC's regulation governing the design of emergency core cooling systems (ECCS).

[Federal Register Volume 80, Number 75 (Monday, April 20, 2015)]
[Proposed Rules]
[Pages 21658-21659]
From the Federal Register Online  [www.thefederalregister.org]
[FR Doc No: 2015-08964]


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Proposed Rules
                                                Federal Register
________________________________________________________________________

This section of the FEDERAL REGISTER contains notices to the public of 
the proposed issuance of rules and regulations. The purpose of these 
notices is to give interested persons an opportunity to participate in 
the rule making prior to the adoption of the final rules.

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Federal Register / Vol. 80, No. 75 / Monday, April 20, 2015 / 
Proposed Rules

[[Page 21658]]



NUCLEAR REGULATORY COMMISSION

10 CFR Parts 50 and 52

[NRC-2015-0095]
RIN 3150-AH42


Alternate Risk-Informed Approach for Addressing the Effects of 
Debris on Post-Accident Long-Term Core Cooling

AGENCY: Nuclear Regulatory Commission.

ACTION: Draft regulatory guide; request for comment.

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SUMMARY: The U.S. Nuclear Regulatory Commission (NRC) is issuing for 
public comment draft regulatory guide (DG), DG-1322, ``Alternate Risk-
Informed Approach for Addressing the Effects of Debris On Post-Accident 
Long-Term Core Cooling.'' This DG proposes new guidance that describes 
methods and procedures that the NRC staff considers acceptable for 
complying with a voluntary, risk-informed alternative in a proposed 
revision of the NRC's regulation governing the design of emergency core 
cooling systems (ECCS).

DATES: Submit comments by July 6, 2015. Comments received after this 
date will be considered if it is practical to do so, but the NRC is 
able to ensure consideration only for comments received on or before 
this date. Although a time limit is given, comments and suggestions in 
connection with items for inclusion in guides currently being developed 
or improvements in all published guides are encouraged at any time.

ADDRESSES: You may submit comments by any of the following methods 
(unless this document describes a different method for submitting 
comments on a specified subject):
     Federal Rulemaking Web site: Go to http://www.regulations.gov and search for Docket ID NRC-2015-0095. Address 
questions about NRC dockets to Carol Gallagher; telephone: 301-415-
3463; email: [email protected]. For technical questions, contact 
the individual(s) listed in the FOR FURTHER INFORMATION CONTACT section 
of this document.
     Mail comments to: Cindy Bladey, Office of Administration, 
Mail Stop: OWFN-12H08, U.S. Nuclear Regulatory Commission, Washington, 
DC 20555-0001.
    For additional direction on accessing information and submitting 
comments, see ``Obtaining Information and Submitting Comments'' in the 
SUPPLEMENTARY INFORMATION section of this document.

FOR FURTHER INFORMATION CONTACT: Steven A. Laur, telephone: 301-415-
1465, email: [email protected], and Steve Burton, telephone: 301-415-
7000, email: [email protected]. Both are staff of the U.S. Nuclear 
Regulatory Commission, Washington, DC 20555-0001.

SUPPLEMENTARY INFORMATION:

I. Obtaining Information and Submitting Comments

A. Obtaining Information

    Please refer to Docket ID NRC-2015-0095 when contacting the NRC 
about the availability of information regarding this document. You may 
obtain publically-available information related to this document by any 
of the following methods:
     Federal Rulemaking Web site: Go to http://www.regulations.gov and search for Docket ID NRC-2015-0095.
     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 [email protected]. The 
ADAMS accession number for each document referenced (if it available in 
ADAMS) is provided the first time that a document is referenced. The DG 
is electronically available in ADAMS under Accession No. ML15023A025.
     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-2015-0095 in the subject line of your 
comment submission, in order to ensure that the NRC is able to make 
your comment submission available to the public in this docket.
    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. Additional Information

    The NRC is issuing for public comment a DG in the NRC's 
``Regulatory Guide'' series. This series was developed to describe and 
make available to the public information regarding methods that are 
acceptable to the NRC staff for implementing specific parts of the 
NRC's regulations, techniques that the staff uses in evaluating 
specific problems or postulated accidents, and data that the staff 
needs in its review of applications for permits and licenses.
    The DG, entitled, ``Alternate Risk-Informed Approach for Addressing 
the Effects of Debris On Post-Accident Long-Term Core Cooling,'' is a 
proposed new guide temporarily identified by its task number, DG-1322. 
This DG-1322 proposes new guidance that describes methods and 
procedures that the staff considers acceptable for complying with a 
voluntary, risk-informed alternative in a proposed revision of the 
NRC's regulation governing the design of ECCS, section 50.46c of Title 
10 of the

[[Page 21659]]

Code of Federal Regulations (10 CFR), ``Emergency core cooling system 
performance during loss-of-coolant accidents (LOCA),'' with respect to 
the effects of debris during long-term cooling.
    The voluntary alternative was included in the proposed 10 CFR 
50.46c rule at the direction of the Commission in the Staff 
Requirements Memorandum (SRM) regarding SECY-12-0093 ``Closure Options 
for Generic Safety Issue--191, Assessment of Debris Accumulation on 
Pressurized-Water Reactor Sump Performance,'' and in the SRM regarding 
SECY-12-0034 ``Proposed Rulemaking--10 CFR 50.46c: Emergency Core 
Cooling System Performance During Loss-of-Coolant Accidents (RIN 3150-
AH42).'' This guide is intended to provide a consistent approach for 
licensees to use when performing a risk assessment of the complex 
phenomena associated with debris generation and transport, and the 
resulting effect on long-term core cooling.

III. Backfitting and Issue Finality

    This DG, if finalized, would not constitute backfitting as defined 
in Sec.  50.109 (the Backfit Rule), and would not be otherwise 
inconsistent with the issue finality provisions in 10 CFR part 52, 
``Licenses, Certifications and Approvals for Nuclear Power Plants.'' 
The NRC published a proposed revision of 10 CFR 50.46c on March 24, 
2014 (79 FR 16106). The proposed rule includes the option of allowing 
an applicant or licensee to address the effects of debris on longterm 
cooling with respect to ECCS performance requirements in Sec.  50.46c 
and GDC-35 using a risk-informed approach. The proposed rule would also 
allow applicants and licensees who select the option to use the same 
approach in demonstrating compliance with GDC-38 and GDC-41. This DG 
provides guidance on one possible means for implementing that option. 
The proposed guidance does not exceed the scope of the proposed rule. 
Therefore, the backfitting and issue finality discussion for the 
proposed rule applies to this DG, and further consideration and 
discussion of backfitting and issue finality for the DG is not 
necessary.

    Dated at Rockville, Maryland, this 13th day of April 2015.

    For the Nuclear Regulatory Commission.
Harriet Karagiannis,
Acting Chief, Regulatory Guidance and Generic Issues Branch, Division 
of Engineering, Office of Nuclear Regulatory Research.
[FR Doc. 2015-08964 Filed 4-17-15; 8:45 am]
 BILLING CODE 7590-01-P