[Federal Register Volume 78, Number 84 (Wednesday, May 1, 2013)]
[Pages 25487-25488]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2013-10254]




Final License Renewal Interim Staff Guidance LR-ISG-2012-01: Wall 
Thinning Due to Erosion Mechanisms

AGENCY: Nuclear Regulatory Commission.

ACTION: Interim staff guidance; issuance.


SUMMARY: The U.S. Nuclear Regulatory Commission (NRC) is issuing the 
final License Renewal Interim Staff Guidance (LR-ISG), LR-ISG-2012-01, 
``Wall Thinning Due to Erosion Mechanisms.'' This LR-ISG revises an NRC 
staff-recommended aging management program (AMP) in NUREG-1801, 
Revision 2, ``Generic Aging Lessons Learned (GALL) Report,'' and the 
NRC staff's aging management review procedure and acceptance criteria 
contained in NUREG-1800, Revision 2, ``Standard Review Plan for Review 
of License Renewal Applications for Nuclear Power Plants'' (SRP-LR), to 
address wall thinning due to various erosion mechanisms for piping and 
components within the scope of the Requirements for Renewal of 
Operating Licenses for Nuclear Power Plants. This LR-ISG changes the 
recommendations in GALL Report, Revision 2, AMP XI.M17, ``Flow-
Accelerated Corrosion,'' based on the staff's review of several license 
renewal applications' flow-accelerated corrosion AMPs and stakeholder 

ADDRESSES: Please refer to Docket ID NRC-2012-0170 when contacting the 
NRC about the availability of information regarding this document. You 
may access information related to this document, which the NRC 
possesses and is publicly available, using any of the following 
     Federal Rulemaking Web site: Go to http://www.regulations.gov and search for Docket ID NRC-2012-0170. Address 
questions about NRC dockets to Carol Gallagher; telephone: 301-492-
3668; email: [email protected].
     NRC's Agencywide Document Access and Management System 
(ADAMS): You may access publicly-available documents online in the NRC 
library at http://www.nrc.gov/reading-rm/adams.html. To begin the 
search, select ``ADAMS Public Document'' 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 final LR-ISG-2012-01 is 
available under ADAMS Accession No. ML12352A057. The GALL Report and 
SRP-LR are available under ADAMS Accession Nos. ML103490041 and 
ML103490036, respectively.
     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.
     NRC's Interim Staff Guidance Web site: LR-ISG documents 
are also available online under the ``License Renewal'' heading at 

FOR FURTHER INFORMATION CONTACT: Mr. James Gavula, telephone: 630-829-
9755, email: [email protected]; or Ms. Evelyn Gettys, telephone: 
301-415-4029; or email: [email protected]. Both of the Office of 
Nuclear Reactor Regulation, U.S. Nuclear Regulatory Commission, 
Washington, DC 20555-0001.


Background Information

    The NRC issues LR-ISGs to communicate insights and lessons learned 
and to address emergent issues not covered in license renewal guidance 
documents, such as the GALL Report and SRP-LR. In this way, the NRC 
staff and stakeholders may use the guidance in an LR-ISG document 
before it is incorporated into a formal license renewal guidance 
document revision. The NRC staff issues LR-ISGs in accordance with the 
LR-ISG Process, Revision 2 (ADAMS Accession No. ML100920158), for which 
a notice of availability was published in the Federal Register on June 
22, 2010 (75 FR 35510).
    The NRC staff developed LR-ISG-2012-01 to: (a) Revise the 
definition of ``wall thinning'' to include erosion mechanisms; (b) 
revise the definition of ``flow-accelerated corrosion'' and ``erosion'' 
to align them with the definitions commonly used in industry; (c) allow 
applicants to monitor wall thinning caused by erosion mechanisms in the 
AMP for flow-accelerated corrosion by (i) ensuring that extent of 
condition reviews identify any other components susceptible to similar 
degradation, and (ii) verifying that corrective actions have either 
eliminated the erosion mechanism, precluding the need for ongoing aging 
management activities, or included periodic wall thickness measurements 
in an AMP; and (d) make miscellaneous and editorial changes.
    On July 13, 2012 (77 FR 41457), the NRC requested public comments 
on draft LR-ISG-2012-01. In response, the Nuclear Energy Institute 
(NEI) provided comments by letter dated August 27, 2012 (ADAMS 
Accession No. ML12244A004), which integrated multiple industry comments 
on the subject LR-ISG, including those submitted separately by Wolf 
Creek Nuclear Operating Corporation in a letter dated August 23, 2012 
(ADAMS Accession No. ML12250A668). No other comments were submitted.
    NEI's comments broadly recommended that the NRC create a separate 
AMP for mechanical erosion mechanisms, rather than mixing these 
phenomena into the existing Flow-Accelerated Corrosion program. The 
industry believed that the change proposed by the NRC would cause 
confusion in the current Flow-Accelerated Corrosion programs because of 
different susceptibility criteria and inspection selection methods and 
strategies for erosion mechanisms.
    The NRC considered these comments in developing the final LR-ISG, 
but ultimately determined that the LR-ISG should be published in its 
current format. The staff notes that no applicant for a renewed 
licensee has ever proposed a separate AMP to address erosion 
mechanisms, but they have included activities for managing erosion 
mechanisms in either the Flow-Accelerated Corrosion or the Open-Cycle 
Cooling Water System AMPs. The NRC staff has approved both approaches, 
and in that regard, LR-ISG-2012-01 is consistent with existing industry 
and NRC practice. The staff further notes that it has not detected any 
confusion, as postulated by the industry, on the part of licensees that 
have chosen to include erosion mechanisms in the Flow-Accelerated 
Corrosion program. Detailed responses to the comments can be found in 
Appendix E of the final LR-ISG.

[[Page 25488]]

    The final LR-ISG-2012-01 is approved for NRC staff and stakeholder 
use and will be incorporated into the NRC's next formal license renewal 
guidance document revision.

Congressional Review Act

    In accordance with the Congressional Review Act of 1996, the NRC 
has determined that this action is not a major rule and has verified 
this determination with the Office of Information and Regulatory 
Affairs of the Office of Management and Budget.

Backfitting and Issue Finality

    Issuance of this final LR-ISG does not constitute backfitting as 
defined in Section 50.109 of Title 10 of the Code of Federal 
Regulations (10 CFR), (the Backfit Rule) and is not otherwise 
inconsistent with the issue finality provisions in 10 CFR Part 52, 
``Licenses, Certifications, and Approvals for Nuclear Power Plants.'' 
As discussed in the ``Backfitting and Issue Finality'' section of LR-
ISG-2012-01, the LR-ISG is directed to holders of operating licenses or 
combined licenses who are currently in the license renewal process or 
plan to enter the process in the future. The LR-ISG is not directed to 
holders of operating licenses or combined licenses until they apply for 
license renewal. The LR-ISG is also not directed to licensees who 
already hold renewed operating or combined licenses.

    Dated at Rockville, Maryland, this 22nd day of April 2013.

    For the Nuclear Regulatory Commission.
John W. Lubinski,
Director, Division of License Renewal, Office of Nuclear Reactor 
[FR Doc. 2013-10254 Filed 4-30-13; 8:45 am]