[Federal Register Volume 77, Number 92 (Friday, May 11, 2012)]
[Notices]
[Pages 27815-27816]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2012-11424]


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NUCLEAR REGULATORY COMMISSION

[NRC-2011-0256]


Aging Management of Stainless Steel Structures and Components in 
Treated Borated Water

AGENCY: Nuclear Regulatory Commission.

ACTION: Interim staff guidance; issuance.

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SUMMARY: The U.S. Nuclear Regulatory Commission (NRC) is issuing 
License Renewal Interim Staff Guidance (LR-ISG), LR-ISG-2011-01, 
``Aging Management of Stainless Steel Structures and Components in 
Treated Borated Water.'' This LR-ISG revises the guidance in the 
Standard Review Plan for Review of License Renewal Applications for 
Nuclear Power Plants (SRP-LR) and Generic Aging Lessons Learned (GALL) 
Report for the aging management of stainless steel structures and 
components exposed to treated borated water. The NRC published Revision 
2 of the SRP-LR and GALL Report in December 2010, and they are 
available in the NRC's Agencywide Documents Access and Management 
System (ADAMS) under Accession Nos. ML103490041 and ML103490036, 
respectively.

ADDRESSES: You can access publicly available documents related to this 
document using the following methods:
     NRC's Public Document Room (PDR): The public may examine 
and have copied, for a fee, publicly available documents at the NRC's 
PDR, Room O1-F21, One White Flint North, 11555 Rockville Pike, 
Rockville, Maryland 20852.
     ADAMS: Publicly available documents created or received at 
the NRC are available online in the NRC Library at http://www.nrc.gov/reading-rm/adams.html. From this page, the public can gain entry into 
ADAMS, which provides text and image files of the NRC's public 
documents. If you do not have access to ADAMS or if there are problems 
in accessing the documents located in ADAMS, contact the NRC's PDR 
reference staff at 1-800-397-4209, 301-415-4737, or by email to 
[email protected]. The LR-ISG-2011-01 is available under ADAMS 
Accession No. ML12034A047.

[[Page 27816]]

     Federal Rulemaking Web Site: Public comments and 
supporting materials related to this final rule can be found at http://www.regulations.gov by searching on Docket ID NRC-2011-0256. Address 
questions about NRC dockets to Carol Gallagher, telephone: 301-492-
3668; email: [email protected].
     NRC's Interim Staff Guidance Web Site: LR-ISG documents 
are also available online under the ``License Renewal'' heading at 
http://www.nrc.gov/reading-rm/doc-collections/#int.

FOR FURTHER INFORMATION CONTACT: Dr. John Wise, Division of License 
Renewal, Office of Nuclear Reactor Regulation, U.S. Nuclear Regulatory 
Commission, Washington, DC 20555-0001; telephone: 301-415-8489, or 
email: [email protected], or Ms. Evelyn Gettys, Division of License 
Renewal, Office of Nuclear Reactor Regulation, U.S. Nuclear Regulatory 
Commission, Washington, DC 20555-001; telephone: 301-415-4029, or 
email: [email protected].

SUPPLEMENTARY INFORMATION: 

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 has determined that existing guidance in the SRP-LR 
and GALL Report may not adequately address aging management of 
stainless steel structures and components exposed to treated borated 
water. Specifically, for pressurized water reactors, the guidance 
inappropriately credits boron as a corrosion inhibitor in place of 
other aging management activities. As a result, aging effects such as 
loss of material, cracking, and reduction of heat transfer may not be 
adequately managed. The staff has revised the guidance in the SRP-LR 
and GALL Report to align the guidance for treated borated water with 
that for treated (non-borated) water. The revisions include adding the 
One-Time Inspection program to verify the effectiveness of the Water 
Chemistry program to manage loss of material and cracking of stainless 
steel structures and components exposed to treated borated water and 
adding reduction of heat transfer due to fouling as an aging effect 
requiring management for stainless steel heat exchanger tubes exposed 
to treated borated water.
    On November 8, 2011, the NRC staff issued a Federal Register notice 
(76 FR 69292) to request public comments on draft LR-ISG-2011-01 (ADAMS 
Accession No. ML112360626). In response, the NRC received comments from 
the Nuclear Energy Institute by letter dated December 13, 2011 (ADAMS 
Accession No. ML11350A112) and Exelon Generation Company, LLC by letter 
dated December 14, 2011 (ADAMS Accession No. ML11353A424). The Nuclear 
Energy Institute and Exelon provided similar comments suggesting the 
expansion of the new guidance to additional components for aging 
management of loss of material and cracking, but also suggesting the 
withdrawal or revision of the new guidance for management of reduction 
of heat transfer in heat exchangers.
    The staff incorporated the comments regarding the expansion of the 
new guidance to additional components for management of loss of 
material and cracking, because the staff considered these changes as 
providing important clarity to license renewal applicants. However, the 
staff did not incorporate the comments regarding the withdrawal or 
revision of the new guidance for heat exchangers. The comments 
regarding the heat exchanger guidance were that the proposed one-time 
inspection was either not necessary due to lack of operating experience 
with fouling of heat exchangers in the chemical and volume control 
system, or not an appropriate aging management method due to the 
potential for inspection personnel to be exposed to significant 
radiation. The staff considers the one-time inspection approach as 
appropriate for components with limited operating experience of age-
related degradation. If age-related degradation were known, the GALL 
Report One-Time Inspection program recommends a periodic inspection 
approach. Also, the one-time inspection guidance does not preclude a 
license renewal applicant from proposing and justifying other aging 
management approaches that minimize dosage. For these reasons, the 
staff chose not to eliminate the new guidance for heat exchangers.
    The final LR-ISG-2011-01 is approved for NRC staff and stakeholder 
use and will be incorporated into the NRC's next formal license renewal 
guidance document revision.

Backfitting and Issue Finality

    Issuance of this final LR-ISG does not constitute backfitting as 
defined in 10 CFR 50.109 (the Backfit Rule) and is not otherwise 
inconsistent with the issue finality provisions in Part 52, ``Licenses, 
Certifications, and Approvals for Nuclear Power Plants,'' of 10 CFR. As 
discussed in the ``Backfitting Discussion'' section of final LR-ISG-
2011-01, the LR-ISG is directed to holders of operating licenses or 
combined licenses who are currently in the license renewal process. 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 3rd day of May, 2012.

    For the Nuclear Regulatory Commission.
Melanie A. Galloway,
Acting Director, Division of License Renewal, Office of Nuclear Reactor 
Regulation.
[FR Doc. 2012-11424 Filed 5-10-12; 8:45 am]
BILLING CODE 7590-01-P