83 FR 2331 - Approval of American Society of Mechanical Engineers' Code Cases

NUCLEAR REGULATORY COMMISSION

Federal Register Volume 83, Issue 11 (January 17, 2018)

Page Range		2331-2354
FR Document		2018-00112
The U.S. Nuclear Regulatory Commission (NRC) is amending its regulations to incorporate by reference (IBR) the latest revisions of three regulatory guides (RGs) approving new, revised, and reaffirmed Code Cases published by the American Society of Mechanical Engineers (ASME). This action allows nuclear power plant licensees and applicants for construction permits, operating licenses, combined licenses, standard design certifications, standard design approvals and manufacturing licenses to voluntarily use the Code Cases listed in these RGs as alternatives to engineering standards for the construction, inservice inspection (ISI), and inservice testing (IST) of nuclear power plant components. These engineering standards are set forth in the ASME's Boiler and Pressure Vessel (BPV) Codes and ASME Operation and Maintenance (OM) Codes, which are currently incorporated by reference into the NRC's regulations. This final rule announces the availability of the final versions of the three RGs that are being incorporated by reference. Further, the final rule announces the availability of a related RG, not incorporated by reference into the NRC's regulations that lists Code Cases that the NRC has not approved for use.
Federal Register, Volume 83 Issue 11 (Wednesday, January 17, 2018)
[Federal Register Volume 83, Number 11 (Wednesday, January 17, 2018)]
[Rules and Regulations]
[Pages 2331-2354]
From the Federal Register Online  [www.thefederalregister.org]
[FR Doc No: 2018-00112]


=======================================================================
-----------------------------------------------------------------------

NUCLEAR REGULATORY COMMISSION

10 CFR Part 50

[NRC-2012-0059]
RIN 3150-AJ13


Approval of American Society of Mechanical Engineers' Code Cases

AGENCY: Nuclear Regulatory Commission.

ACTION: Final rule.

-----------------------------------------------------------------------

SUMMARY: The U.S. Nuclear Regulatory Commission (NRC) is amending its 
regulations to incorporate by reference (IBR) the latest revisions of 
three regulatory guides (RGs) approving new, revised, and reaffirmed 
Code Cases published by the American Society of Mechanical Engineers 
(ASME). This action allows nuclear power plant licensees and applicants 
for construction permits, operating licenses, combined licenses, 
standard design certifications, standard design approvals and 
manufacturing licenses to voluntarily use the Code Cases listed in 
these RGs as alternatives to engineering standards for the 
construction, inservice inspection (ISI), and inservice testing (IST) 
of nuclear power plant components. These engineering standards are set 
forth in the ASME's Boiler and Pressure Vessel (BPV) Codes and ASME 
Operation and Maintenance (OM) Codes, which are currently incorporated 
by reference into the NRC's regulations. This final rule announces the 
availability of the final versions of the three RGs that are being 
incorporated by reference. Further, the final rule announces the 
availability of a related RG, not incorporated by reference into the 
NRC's regulations that lists Code Cases that the NRC has not approved 
for use.

DATES: This final rule is effective on February 16, 2018. The 
incorporation by reference of certain publications listed in the 
regulation is approved by the Director of the Federal Register as of 
February 16, 2018.

ADDRESSES: Please refer to Docket ID NRC-2012-0059 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 Website: Go to http://www.regulations.gov and search for Docket ID NRC-2012-0059. Address 
questions about NRC dockets to Carol Gallagher; telephone: 301-415-
3463; email: [email protected]. For technical questions contact 
the individuals listed in the FOR FURTHER INFORMATION CONTACT section 
of this document.
     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]. For 
the convenience of the reader, instructions about obtaining materials 
referenced in this document are provided in the ``Availability of 
Documents'' section.
     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.

FOR FURTHER INFORMATION CONTACT: Jennifer Tobin, Office of Nuclear 
Reactor Regulation, telephone: 301-415-2328, email: 
[email protected]; or Giovanni Facco, Office of Nuclear Regulatory 
Research, telephone: 301-415-6337; email: [email protected]. Both 
are staff of the U.S. Nuclear Regulatory Commission, Washington, DC 
20555-0001.

SUPPLEMENTARY INFORMATION: 

Executive Summary

    The purpose of this regulatory action is to incorporate by 
reference into the NRC's regulations the latest revisions of three RGs. 
The three RGs identify new, revised, and reaffirmed Code Cases 
published by the ASME, which the NRC has determined are acceptable for 
use as alternatives to certain provisions of the ASME BPV Codes and 
ASME OM Codes, currently incorporated by reference into the NRC's 
regulations. The three RGs that the NRC is incorporating by reference 
are RG 1.84, ``Design, Fabrication, and Materials Code Case 
Acceptability, ASME Section III,'' Revision 37; RG 1.147, ``Inservice 
Inspection Code Case Acceptability, ASME Section XI, Division 1,'' 
Revision 18; and RG 1.192, ``Operation and Maintenance Code Case 
Acceptability, ASME OM Code,'' Revision 2. This regulatory action 
allows nuclear power plant licensees and applicants for construction 
permits, operating licenses, combined licenses, standard design 
certifications, standard design approvals, and manufacturing licenses 
to voluntarily use the Code Cases, newly listed in these revised RGs, 
as

[[Page 2332]]

alternatives to engineering standards for the design, construction, 
ISI, and IST, and repair/replacement of nuclear power plant components. 
In this notice, the NRC also notifies the public of the availability of 
RG 1.193, ``ASME Code Cases Not Approved for Use,'' Revision 5. The 
regulatory guide lists Code Cases that the NRC has not approved for 
generic use, and will not be incorporated by reference into the NRC's 
regulations.
    The NRC prepared a regulatory analysis (ADAMS Accession No. 
ML16285A013) to identify the benefits and costs associated with this 
final rule. The regulatory analysis prepared for this rulemaking was 
used to determine if the rule is cost-effective, overall, and to help 
the NRC evaluate potentially costly conditions placed on specific 
provisions of the ASME Code Cases, which are the subject of this 
rulemaking.

                      Table 1--Cost-Benefit Summary
------------------------------------------------------------------------
                                                        Alternative 2--
                                                            the rule
                                                        alternative net
                                                        benefits (costs)
                      Objective                           (net present
                                                           value, 7%
                                                         discount rate)
                                                          ($ million)
------------------------------------------------------------------------
Industry.............................................               2.42
NRC..................................................               2.52
Net Benefit..........................................               4.94
------------------------------------------------------------------------

    Table 1 summarizes the benefits and costs for the alternative of 
proceeding with the final rule (Alternative 2) and shows that the final 
rule is quantitatively cost-beneficial with a net benefit of $4.94 
million to both the industry and the NRC when compared to the 
regulatory baseline (Alternative 1). The regulatory analysis shows that 
implementing the final rule is quantitatively cost-effective and an 
efficient use of the NRC's and Industry's resources. Uncertainty 
analysis shows that the net benefit ranges from $2.86 million to $6.90 
million with a mean of $4.94 million. Because the rulemaking 
alternative is cost-effective, the rulemaking approach is recommended.
    There are several benefits associated with this final rule. Under 
this final rule, a licensee of a nuclear power plant would no longer be 
required to submit a Code Case alternative request under the new Sec.  
50.55a(z) of Title 10 of the Code of Federal Regulations (10 CFR), 
which would provide an averted cost of $7.75 million (7[dash]percent 
net present value) to the licensee. Additionally, the NRC would not 
receive Code Case alternative request submittals, which would provide 
an averted cost of $2.52 million (7[dash]percent net present value) to 
the NRC.

Table of Contents

I. Background
II. Discussion
    A. ASME Code Cases Approved for Unconditional Use
    B. ASME Code Cases Approved for Use with Conditions
     ASME BPV Code, Section III Code Cases (RG 1.84)
     ASME BPV Code, Section XI Code Cases (RG 1.147)
     OM Code Cases (RG 1.192)
    C. ASME Code Cases not Approved for Use (RG 1.193)
III. Opportunities for Public Participation
IV. Public Comment Analysis
V. Section-by-Section Analysis
VI. Regulatory Flexibility Certification
VII. Regulatory Analysis
VIII. Backfitting and Issue Finality
IX. Plain Writing
X. Environmental Assessment and Final Finding of No Significant 
Environmental Impact
XI. Paperwork Reduction Act
XII. Congressional Review Act
XIII. Voluntary Consensus Standards
XIV. Incorporation by Reference--Reasonable Availability to 
Interested Parties
XV. Availability of Documents

I. Background

    The ASME develops and publishes the ASME BPV Code, which contains 
requirements for the design, construction, and ISI and examination of 
nuclear power plant components, and ASME's Nuclear Power Plants (OM) 
Code,\1\ which contains requirements for IST of nuclear power plant 
components. In response to BPV Code and OM Code user requests, the ASME 
develops Code Cases that provide alternatives to BPV Code and OM Code 
requirements under special circumstances.
---------------------------------------------------------------------------

    \1\ The editions and addenda of the ASME Code for Operation and 
Maintenance of Nuclear Power Plants have had different titles from 
2005 to 2012, and are referred to collectively in this rule as the 
``OM Code.''
---------------------------------------------------------------------------

    The NRC approves and can mandate the use of the ASME BPV Codes and 
OM Codes in Sec.  50.55a, ``Codes and standards,'' through the process 
of incorporation by reference. As such, each provision of the ASME 
Codes incorporated by reference into and mandated by Sec.  50.55a 
constitutes a legally[dash]binding NRC requirement imposed by the 
regulations. As noted previously, ASME Code Cases, for the most part, 
represent alternative approaches for complying with provisions of the 
ASME BPV Codes and OM Codes. Accordingly, the NRC periodically amends 
Sec.  50.55a to incorporate by reference the NRC's RGs listing approved 
ASME Code Cases that may be used as alternatives to the BPV Codes and 
OM Codes.\2\
---------------------------------------------------------------------------

    \2\ See Federal Register notice, ``Incorporation by Reference of 
ASME BPV and OM Code Cases'' (68 FR 40469; July 8, 2003).
---------------------------------------------------------------------------

    This rulemaking is the latest in a series of rulemakings that 
incorporates by reference new versions of several RGs identifying new, 
revised, and reaffirmed,\3\ and unconditionally or conditionally 
acceptable ASME Code Cases that the NRC approves for use. In developing 
these RGs, the staff reviews ASME BPV and OM Code Cases, determines the 
acceptability of each Code Case, and publishes its findings in the RGs. 
The RGs are revised periodically, as new Code Cases and are published 
by the ASME. The NRC incorporates by reference the RGs, listing 
acceptable and conditionally acceptable ASME Code Cases into Sec.  
50.55a. Currently, NRC RG 1.84, ``Design, Fabrication, and Materials 
Code Case Acceptability, ASME Section III,'' Revision 36; RG 1.147, 
``Inservice Inspection Code Case Acceptability, ASME Section XI, 
Division 1,'' Revision 17; and RG 1.192, ``Operation and Maintenance 
Code Case Acceptability, ASME OM Code,'' Revision 1, are incorporated 
into the NRC's regulations in Sec.  50.55a.
---------------------------------------------------------------------------

    \3\ Code Cases are categorized by ASME as one of three types: 
new, revised, or reaffirmed. A new Code Case provides for a new 
alternative to specific ASME Code provisions or addresses a new 
need. The ASME defines a revised Code Case to be a revision 
(modification) to an existing Code Case to address, for example, 
technological advancements in examination techniques or to address 
NRC conditions imposed in one of the RGs that have been incorporated 
by reference into Sec.  50.55a. The ASME defines ``reaffirmed'' as 
an OM Code Case to be one that does not have any change to technical 
content, but includes editorial changes.
---------------------------------------------------------------------------

II. Discussion

    This rule incorporates by reference the latest revisions of the NRC 
RGs that list ASME BPV and OM Code Cases that the NRC finds to be 
acceptable, or acceptable with NRC[dash]specified conditions 
(``conditionally acceptable''). Regulatory Guide 1.84, Revision 37, 
supersedes Revision 36; RG 1.147, Revision 18, supersedes Revision 17; 
and RG 1.192, Revision 2, supersedes Revision 1. The NRC also publishes 
a document (RG 1.193, ``ASME Code Cases Not Approved for Use'') that 
lists Code Cases that the NRC has not approved for generic use. The RG 
1.193 is not incorporated by reference into the NRC's regulations; 
however, in this final rule, the NRC notes the availability of RG 
1.193, Revision 5.
    The ASME Code Cases that are the subject of this rulemaking are the 
new, revised, and reaffirmed Section III and Section XI Code Cases 
listed in

[[Page 2333]]

Supplement 11 to the 2007 BPV Code through Supplement 10 to the 2010 
BPV Code, and the OM Code Cases published with the 2009 Edition through 
the 2012 Edition.
    The latest editions and addenda of the ASME BPV and OM Codes that 
the NRC has approved for use are referenced in Sec.  50.55a. The ASME 
also publishes Code Cases that provide alternatives to existing Code 
requirements that the ASME developed and approved. This rule 
incorporates by reference the latest revisions of RGs 1.84, 1.147, and 
1.192. This rule allows nuclear power plant licensees and applicants 
for construction permits, operating licenses, combined licenses, 
standard design certifications, standard design approvals, and 
manufacturing licenses, under the regulations that govern license 
certifications, to voluntarily use the Code Cases listed in these RGs 
as suitable alternatives to certain provisions of the ASME BPV and OM 
Codes for the construction, ISI, and IST of nuclear power plant 
components. This action is consistent with the provisions of the 
National Technology Transfer and Advancement Act of 1995 (NTTAA), 
Public Law 104-113, which encourages Federal regulatory agencies to 
consider adopting industry consensus standards as an alternative to de 
novo agency development of standards affecting an industry. This action 
is also consistent with the NRC policy of evaluating the latest 
versions of consensus standards, in terms of their suitability for 
endorsement by regulations or regulatory guides.
    The NRC follows a three-step process to determine acceptability of 
new, revised, and reaffirmed Code Cases, and the need for regulatory 
positions on the use of these Code Cases. This process was employed in 
the review of the Code Cases in Supplement 11 to the 2007 Edition 
through Supplement 10 to the 2010 Edition of the BPV Code and the 2009 
Edition through the 2012 Edition of the OM Code. The Code Cases in 
these supplements and OM Editions and Addenda are the subject of this 
rule. First, the ASME develops Code Cases through a consensus 
development process, as administered by the American National Standards 
Institute (ANSI), which ensures that the various technical interests 
(e.g., utility, manufacturing, insurance, regulatory) are represented 
on standards development committees and that their view points are 
addressed fairly. The NRC staff actively participates in discussions 
and technical debates of the task groups, working groups, subgroups, 
and standards committees regarding the development of new and revised 
standards. The Code Case process includes the development of a 
technical justification in support of each new or revised Code Case. 
The ASME committee meetings are open to the public and attendees are 
encouraged to participate. Task groups, working groups, and subgroups 
report to respective standards committees. The standards committee is 
the decisive consensus committee in that it ensures that the 
development process fully complies with the ANSI consensus process.
    Second, the standards committee transmits a first consideration 
letter ballot to every member of the standards committee, requesting 
comment or approval of new and revised Code Cases. Code Cases are 
approved by the standards committee from the first consideration letter 
ballot when: (1) At least two thirds of the eligible consensus 
committee membership vote approved; (2) there are no disapprovals from 
the standards committee; and (3) no substantive comments are received 
from the ASME oversight committees such as the Technical Oversight 
Management Committee (TOMC). The TOMC's duties, in part, are to oversee 
various standards committees to ensure technical adequacy and to 
provide recommendations in the development of codes and standards, as 
required. Code Cases that were disapproved or received substantive 
comments from the first consideration ballot are reviewed by the 
working level group(s) responsible for their development to consider 
the comments received. These Code Cases are approved by the standards 
committee on second consideration when at least two thirds of the 
eligible consensus committee membership vote approved, and there are no 
more than three disapprovals from the consensus committee.
    Third, the NRC reviews new, revised, and reaffirmed Code Cases to 
determine their acceptability for incorporation by reference in Sec.  
50.55a through the subject RGs. This rulemaking process, when 
considered together with the ANSI process for developing and approving 
the ASME codes and standards, and Code Cases, constitutes the NRC's 
basis that the Code Cases (with conditions as necessary) provide 
reasonable assurance of adequate protection to public health and 
safety.
    The staff concludes, in accordance with the process described, that 
the Code Cases are technically adequate (with conditions as necessary) 
and consistent with current NRC regulations, and the staff is 
referencing these Code Cases in the applicable RGs, thereby approving 
them for voluntary use, without conditions as addressed in Section A of 
this document; subject to the specified conditions, or as identified in 
Section B of this document. The staff reviewed the new, revised, and 
reaffirmed Code Cases identified in the three RGs being incorporated by 
reference into Sec.  50.55a in this rulemaking. Therefore, the NRC 
approves revising the Sec.  50.55a regulations to incorporate by 
reference the latest revisions of RGs 1.84, 1.147, and 1.192. 
Additionally, the NRC announces the availability of the latest revision 
of RG 1.193.

A. ASME Code Cases Approved for Unconditional Use

    The Code Cases that are discussed in Table I are new, revised, or 
reaffirmed Code Cases that the NRC is approving for use without 
conditions. The NRC concludes, in accordance with the process described 
for review of ASME Code Cases, that each of the ASME Code Cases listed 
in Table I are acceptable for use without conditions. Therefore, the 
NRC is approving for unconditional use the Code Cases listed in Table 
I. This table identifies the regulatory guide the applicable Code Case 
that the NRC is approving for use.
    The NRC revised RG 1.147, Revision 18 to approve Code Case N-786-1 
in Table 1 to address inconsistencies that were identified between the 
NRC's position in the proposed rule regarding the acceptability of Code 
Case N-786 and several licensee requests for alternatives to ASME Code 
requirements, in accordance with Title 10 of the Code of Federal 
Regulations (10 CFR) 50.55a(z), that have utilized Code Case N-786. The 
NRC had authorized the use of Code Case N-786 with modifications. The 
NRC erred in not listing N-786 in DG-1296, Table 2 ``Conditionally 
Acceptable Section XI Code Cases'' with appropriate conditions, in 
order to be consistent with modifications that the NRC has required for 
requested alternatives based on Code Case N-786. In response to 
modifications to N-786 by licensees requesting to use this code case as 
an alternative to ASME Code, ASME revised the code case. The revised 
Code Case, N-786-1 ``Alternative Requirements for Sleeve Reinforcement 
of Class 2 and 3 Moderate[dash]Energy Carbon Steel Piping Section XI, 
Division 1,'' includes modifications that address all of the NRC's 
concerns that the NRC identified in previously approved alternatives 
that were based on N-786. Therefore, the NRC has listed Code Case N-
786-1 in Table 1 of RG 1.147 Revision 18 in lieu of code Case N-786. 
There were no public comments

[[Page 2334]]

received on the inclusion of N-786 in the RG. Code Case N-786-1 is 
included in this final rule because it includes the latest ASME 
guidance and the NRC conditions on the use of this method of repair.

         Table I--ASME Code Cases Approved for Unconditional Use
------------------------------------------------------------------------
         Code Case No.              Supplement             Title
------------------------------------------------------------------------
               Boiler and Pressure Vessel Code Section III
              (addressed in RG 1.84, Revision 37, Table 1)
------------------------------------------------------------------------
N-284-3.......................  7 (10 Edition)...  Metal Containment
                                                    Shell Buckling
                                                    Design Methods,
                                                    Class MC, TC, and SC
                                                    Construction,
                                                    Section III,
                                                    Divisions 1 and 3.
N-500-4.......................  8 (10 Edition)...  Alternative Rules for
                                                    Standard Supports
                                                    for Classes 1, 2, 3,
                                                    and MC, Section III,
                                                    Division 1.
N-520-5.......................  10 (10 Edition)..  Alternative Rules for
                                                    Renewal of Active or
                                                    Expired N-type
                                                    Certificates for
                                                    Plants Not in Active
                                                    Construction,
                                                    Section III,
                                                    Division 1.
N-594-1.......................  8 (10 Edition)...  Repairs to P-4 and P-
                                                    5A Castings without
                                                    Postweld Heat
                                                    Treatment Class 1,
                                                    2, and 3
                                                    Construction,
                                                    Section III,
                                                    Division 1.
N-637-1.......................  3 (10 Edition)...  Use of 44Fe-25Ni-21Cr-
                                                    Mo (Alloy UNS
                                                    N08904) Plate, Bar,
                                                    Fittings, Welded
                                                    Pipe, and Welded
                                                    Tube, Classes 2 and
                                                    3, Section III,
                                                    Division 1.
N-655-2.......................  4 (10 Edition)...  Use of SA-738, Grade
                                                    B, for Metal
                                                    Containment Vessels,
                                                    Class MC, Section
                                                    III, Division 1.
N-763.........................  2 (10 Edition)...  ASTM A 709-06, Grade
                                                    HPS 70W (HPS 485W)
                                                    Plate Material
                                                    Without Postweld
                                                    Heat Treatment as
                                                    Containment Liner
                                                    Material or
                                                    Structural
                                                    Attachments to the
                                                    Containment Liner,
                                                    Section III,
                                                    Division 2.
N-777.........................  4 (10 Edition)...  Calibration of Cv
                                                    Impact Test
                                                    Machines, Section
                                                    III, Divisions 1, 2,
                                                    and 3.
N-785.........................  11 (07 Edition)..  Use of SA-479/SA-
                                                    479M, UNS S41500 for
                                                    Class 1 Welded
                                                    Construction,
                                                    Section III,
                                                    Division 1.
N-811.........................  7 (10 Edition)...  Alternative
                                                    Qualification
                                                    Requirements for
                                                    Concrete Level III
                                                    Inspection
                                                    Personnel, Section
                                                    III, Division 2.
N-815.........................  8 (10 Edition)...  Use of SA-358/SA-358M
                                                    Grades Fabricated as
                                                    Class 3 or Class 4
                                                    Welded Pipe, Class
                                                    CS Core Support
                                                    Construction,
                                                    Section III,
                                                    Division 1.
N-816.........................  8 (10 Edition)...  Use of Temper Bead
                                                    Weld Repair Rules
                                                    Adopted in 2010
                                                    Edition and Earlier
                                                    Editions, Section
                                                    III, Division 1.
N-817.........................  8 (10 Edition)...  Use of Die Forgings,
                                                    SB-247, UNS A96061
                                                    Class T6, With
                                                    Thickness <= 4.000
                                                    in. Material, Class
                                                    2 Construction (1992
                                                    Edition or Later),
                                                    Section III,
                                                    Division 1.
N-819.........................  8 (10 Edition)...  Use of Die Forgings,
                                                    SB-247, UNS A96061
                                                    Class T6, With
                                                    Thickness <= 4.000
                                                    in. Material, Class
                                                    2 Construction (1989
                                                    Edition with the
                                                    1991 Addenda or
                                                    Earlier), Section
                                                    III, Division 1.
N-822.........................  8 (10 Edition)...  Application of the
                                                    ASME Certification
                                                    Mark, Section III,
                                                    Divisions 1, 2, 3,
                                                    and 5.
------------------------------------------------------------------------
               Boiler and Pressure Vessel Code Section XI
              (addressed in RG 1.147, Revision 18, Table 1)
------------------------------------------------------------------------
N-609-1.......................  3 (10 Edition)...  Alternative
                                                    Requirements to
                                                    Stress-Based
                                                    Selection Criteria
                                                    for Category B-J
                                                    Welds, Section XI,
                                                    Division 1.
N-613-2.......................  4 (10 Edition)...  Ultrasonic
                                                    Examination of Full
                                                    Penetration Nozzles
                                                    in Vessels,
                                                    Examination Category
                                                    B-D, Reactor
                                                    Nozzle[dash]To[dash]
                                                    Vessel Welds, and
                                                    Nozzle Inside Radius
                                                    Section Figs. IWB-
                                                    2500-7(a), (b), (c),
                                                    and (d), Section XI,
                                                    Division 1.
N-652-2.......................  9 (10 Edition)...  Alternative
                                                    Requirements to
                                                    Categorize B-G-1, B-
                                                    G-2, and C-D Bolting
                                                    Examination Methods
                                                    and Selection
                                                    Criteria, Section
                                                    XI, Division 1.
N-653-1.......................  9 (10 Edition)...  Qualification
                                                    Requirements for
                                                    Full Structural
                                                    Overlaid Wrought
                                                    Austenitic Piping
                                                    Welds, Section XI,
                                                    Division 1.
N-694-2 \4\...................  1 (13 Edition)...  Evaluation Procedure
                                                    and Acceptance
                                                    Criteria for
                                                    [pressurized water
                                                    reactors] (PWR)
                                                    Reactor Vessel Head
                                                    Penetration Nozzles,
                                                    Section XI, Division
                                                    1.
N-730-1.......................  10 (10 Edition)..  Roll Expansion of
                                                    Class 1 Control Rod
                                                    Drive Bottom Head
                                                    Penetrations in
                                                    [boiling water
                                                    reactors] BWRs,
                                                    Section XI, Division
                                                    1.
N-769-2.......................  10 (10 Edition)..  Roll Expansion of
                                                    Class 1 In[dash]Core
                                                    Housing Bottom Head
                                                    Penetrations in
                                                    BWRs, Section XI,
                                                    Division 1.
N-771.........................  7 (10 Edition)...  Alternative
                                                    Requirements for
                                                    Additional
                                                    Examinations of
                                                    Class 2 or 3 Items,
                                                    Section XI, Division
                                                    1.
N-775.........................  2 (10 Edition)...  Alternative
                                                    Requirements for
                                                    Bolting Affected by
                                                    Borated Water
                                                    Leakage, Section XI,
                                                    Division 1.
N-776.........................  1 (10 Edition)...  Alternative to IWA-
                                                    5244 Requirements
                                                    for Buried Piping,
                                                    Section XI, Division
                                                    1.
N-786-1.......................  5 (10 Edition)...  Alternative
                                                    Requirements for
                                                    Sleeve Reinforcement
                                                    of Class 2 and 3
                                                    Moderate-Energy
                                                    Carbon Steel Piping,
                                                    Section XI, Division
                                                    1.

[[Page 2335]]

 
N-798.........................  4 (10 Edition)...  Alternative Pressure
                                                    Testing Requirements
                                                    for Class 1 Piping
                                                    Between the First
                                                    and Second Vent,
                                                    Drain, and Test
                                                    Isolation Devices,
                                                    Section XI, Division
                                                    1.
N-800.........................  4 (10 Edition)...  Alternative Pressure
                                                    Testing Requirements
                                                    for Class 1 Piping
                                                    Between the First
                                                    and Second Injection
                                                    Valves, Section XI,
                                                    Division 1.
N-803.........................  5 (10 Edition)...  Similar and
                                                    Dissimilar Metal
                                                    Welding Using
                                                    Ambient Temperature
                                                    Automatic or Machine
                                                    Dry Underwater Laser
                                                    Beam Welding (ULBW)
                                                    Temper Bead
                                                    Technique, Section
                                                    XI, Division 1.
N-805.........................  6 (10 Edition)...  Alternative to Class
                                                    1 Extended Boundary
                                                    End of Interval or
                                                    Class 2 System
                                                    Leakage Testing of
                                                    the Reactor Vessel
                                                    Head Flange O-Ring
                                                    Leak-Detection
                                                    System, Section XI,
                                                    Division 1.
N-823.........................  9 (10 Edition)...  Visual Examination,
                                                    Section XI, Division
                                                    1.
N-825 \5\.....................  3 (13 Edition)...  Alternative
                                                    Requirements for
                                                    Examination of
                                                    Control Rod Drive
                                                    Housing Welds,
                                                    Section XI, Division
                                                    1.
N-845 \6\.....................  6 (13 Edition)...  Qualification
                                                    Requirements for
                                                    Bolts and Studs,
                                                    Section XI, Division
                                                    1.
------------------------------------------------------------------------
                   Operation and Maintenance Code (OM)
              (addressed in RG 1.192, Revision 2, Table 1)
------------------------------------------------------------------------
OMN-2.........................  2012 Edition.....  Thermal Relief Valve
                                                    Code Case, OM Code-
                                                    1995, Appendix I.
OMN-5.........................  2012 Edition.....  Testing of Liquid
                                                    Service Relief
                                                    Valves without
                                                    Insulation.
OMN-6.........................  2012 Edition.....  Alternative Rules for
                                                    Digital Instruments.
OMN-7.........................  2012 Edition.....  Alternative
                                                    Requirements for
                                                    Pump Testing.
OMN-8.........................  2012 Edition.....  Alternative Rules for
                                                    Preservice and
                                                    Inservice Testing of
                                                    Power-Operated
                                                    Valves That Are Used
                                                    for System Control
                                                    and Have a Safety
                                                    Function per OM-10,
                                                    ISTC-1.1, or ISTA-
                                                    1100.
OMN-13, Revision 2............  2012 Edition.....  Performance-Based
                                                    Requirements for
                                                    Extending Snubber
                                                    Inservice Visual
                                                    Examination Interval
                                                    at [light water
                                                    reactor] LWR Power
                                                    Plants.
OMN-14........................  2012 Edition.....  Alternative Rules for
                                                    Valve Testing
                                                    Operations and
                                                    Maintenance,
                                                    Appendix I: BWR
                                                    [control rod drive]
                                                    CRD Rupture Disk
                                                    Exclusion.
OMN-15, Revision 2............  2012 Edition.....  Performance-Based
                                                    Requirements for
                                                    Extending the
                                                    Snubber Operational
                                                    Readiness Testing
                                                    Interval at LWR
                                                    Power Plants.
OMN-17........................  2012 Edition.....  Alternative Rules for
                                                    Testing ASME Class 1
                                                    Pressure Relief/
                                                    Safety Valves.
------------------------------------------------------------------------

B. ASME Code Cases Approved for Use With Conditions

    The Code Cases that are discussed in Table II, below, are new, 
revised or reaffirmed Code Cases, which the NRC is approving for use 
with conditions. The NRC has determined that certain Code Cases, as 
issued by the ASME, are generally acceptable for use, but that the 
alternative requirements specified in those Code Cases must be 
supplemented in order to provide an acceptable level of quality and 
safety. Accordingly, the NRC is imposing conditions on the use of these 
Code Cases to modify, limit, or clarify their requirements. The 
conditions specify, for each applicable Code Case, the additional 
activities that must be performed, the limits on the activities 
specified in the Code Case, and the supplemental information needed to 
provide clarity. These ASME Code Cases with conditions are included in 
Table 2 of each RG (i.e., RG 1.84, RG 1.147, and RG 1.192). It is noted 
that both RG 1.147 and RG 1.192 have new ASME Code Cases with 
conditions; however, there are no new ASME Code Cases with conditions 
for RG 1.84.
---------------------------------------------------------------------------

    \4\ Code Case published in Supplement 1 to the 2013 Edition; 
included at the request of ASME.
    \5\ Code Case published in Supplement 3 to the 2013 Edition; 
included at the request of ASME.
    \6\ Code Case published in Supplement 6 to the 2013 Edition; 
included at the request of ASME.

            Table II--Code Cases Approved for Conditional Use
------------------------------------------------------------------------
         Code Case No.              Supplement             Title
------------------------------------------------------------------------
               Boiler and Pressure Vessel Code Section III
              (addressed in RG 1.84, Revision 37, Table 2)
------------------------------------------------------------------------
 No ASME Section III Code Cases are approved for conditional use in this
                                  rule.
               Boiler and Pressure Vessel Code Section XI
              (addressed in RG 1.147, Revision 18, Table 2)
------------------------------------------------------------------------
N-552-1.......................  10 (10 Edition)..  Alternative Methods--
                                                    Qualification for
                                                    Nozzle Inside Radius
                                                    Section from the
                                                    Outside Surface,
                                                    Section XI, Division
                                                    1.
N-576-2.......................  9 (10 Edition)...  Repair of Class 1 and
                                                    2 SB-163, UNS N06600
                                                    Steam Generator
                                                    Tubing, Section XI,
                                                    Division 1.
N-593-2.......................  8 (10 Edition)...  Examination
                                                    Requirements for
                                                    Steam Generator
                                                    Nozzle-to-Vessel
                                                    Welds, Section XI,
                                                    Division 1.

[[Page 2336]]

 
N-638-6.......................  6 (10 Edition)...  Similar and
                                                    Dissimilar Metal
                                                    Welding Using
                                                    Ambient Temperature
                                                    Machine GTAW Temper
                                                    Bead Technique,
                                                    Section XI, Division
                                                    1.
N-662-1.......................  6 (10 Edition)...  Alternative Repair/
                                                    Replacement
                                                    Requirements for
                                                    Items Classified in
                                                    Accordance with Risk-
                                                    Informed Processes,
                                                    Section XI, Division
                                                    1.
N-666-1.......................  9 (10 Edition)...  Weld Overlay of
                                                    Classes 1, 2, and 3
                                                    Socket Welded
                                                    Connections, Section
                                                    XI, Division 1.
N-749.........................  9 (10 Edition)...  Alternative
                                                    Acceptance Criteria
                                                    for Flaws in
                                                    Ferritic Steel
                                                    Components Operating
                                                    in the Upper Shelf
                                                    Temperature Range,
                                                    Section XI, Division
                                                    1.
N-754.........................  6 (10 Edition)...  Optimized Structural
                                                    Dissimilar Metal
                                                    Weld Overlay for
                                                    Mitigation of PWR
                                                    Class 1 Items,
                                                    Section XI, Division
                                                    1.
N-778.........................  6 (10 Edition)...  Alternative
                                                    Requirements for
                                                    Preparation and
                                                    Submittal of
                                                    Inservice Inspection
                                                    Plans, Schedules,
                                                    and Preservice and
                                                    Inservice Summary
                                                    Reports, Section XI,
                                                    Division 1.
N-789.........................  6 (10 Edition)...  Alternative
                                                    Requirements for Pad
                                                    Reinforcement of
                                                    Class 2 and 3
                                                    Moderate Energy
                                                    Carbon Steel Piping
                                                    for Raw Water
                                                    Service, Section XI,
                                                    Division 1.
N-795.........................  3 (10 Edition)...  Alternative
                                                    Requirements for BWR
                                                    Class 1 System
                                                    Leakage Test
                                                    Pressure Following
                                                    Repair/Replacement
                                                    Activities, Section
                                                    XI, Division 1.
N-799.........................  4 (10 Edition)...  Dissimilar Metal
                                                    Welds Joining Vessel
                                                    Nozzles to
                                                    Components, Section
                                                    XI, Division 1.
------------------------------------------------------------------------
                   Operation and Maintenance Code (OM)
              (addressed in RG 1.192, Revision 2, Table 2)
------------------------------------------------------------------------
OMN-1 Revision 1..............  2012 Edition.....  Alternative Rules for
                                                    Preservice and
                                                    Inservice Testing of
                                                    Active Electric
                                                    Motor Operated-Valve
                                                    Assemblies in
                                                    Light[dash]Water
                                                    Reactor Power
                                                    Plants.
OMN-3.........................  2012 Edition.....  Requirements for
                                                    Safety Significance
                                                    Categorization of
                                                    Components Using
                                                    Risk Insights for
                                                    Inservice Testing of
                                                    LWR Power Plants.
OMN-4.........................  2012 Edition.....  Requirements for Risk
                                                    Insights for
                                                    Inservice Testing of
                                                    Check Valves at LWR
                                                    Power Plants.
OMN-9.........................  2012 Edition.....  Use of a Pump Curve
                                                    for Testing.
OMN-12........................  2012 Edition.....  Alternative
                                                    Requirements for
                                                    Inservice Testing
                                                    Using Risk Insights
                                                    for Pneumatically
                                                    and Hydraulically
                                                    Operated Valve
                                                    Assemblies in Light-
                                                    Water Reactor Power
                                                    Plants (OM-Code
                                                    1998, Subsection
                                                    ISTC).
OMN-16 Revision 1.............  2012 Edition.....  Use of a Pump Curve
                                                    for Testing.
OMN-18........................  2012 Edition.....  Alternate Testing
                                                    Requirements for
                                                    Pumps Tested
                                                    Quarterly Within
                                                    20% of
                                                    Design Flow.
OMN-19........................  2012 Edition.....  Alternative Upper
                                                    Limit for the
                                                    Comprehensive Pump
                                                    Test.
OMN-20........................  2012 Edition.....  Inservice Test
                                                    Frequency.
------------------------------------------------------------------------

    The NRC's evaluation of the Code Cases and the reasons for the 
NRC's conditions are discussed in the following paragraphs. Notations 
have been made to indicate the conditions duplicated from previous 
versions of the RG.
ASME BPV Code, Section III Code Cases (RG 1.84)
    There are no new or revised Section III Code Cases in Supplement 11 
to the 2007 Edition through Supplement 10 to the 2010 Edition that the 
NRC is conditionally approving in Revision 37 of RG 1.84.
ASME BPV Code, Section XI Code Cases (RG 1.147)
Code Case N-552-1 [Supplement 10, 2010 Edition]
    Type: Revised.
    Title: Alternative Methods--Qualification for Nozzle Inside Radius 
Section from the Outside Surface, Section XI, Division 1.
    The conditions on Code Case N-552-1 are identical to the conditions 
on N-552 that were approved by the NRC in Revision 16 of RG 1.147 in 
October 2010. The reasons for imposing these conditions in Code Case N-
576 continue to apply to N-576-2. Therefore, these conditions have been 
retained for this Code Case in Revision 18 of RG 1.147.
Code Case N-576-2 [Supplement 9, 2010 Edition]
    Type: Revised.
    Title: Repair of Class 1 and 2 SB-163, UNS N06600 Steam Generator 
Tubing, Section XI, Division 1.
    The conditions on Code Case N-576-2 are identical to the conditions 
on N-576-1 that were approved by the NRC in Revision 17 of RG 1.147 in 
October 2014. The reasons for imposing these conditions are not 
resolved by Code Case N-576-2 and, therefore, these conditions have 
been retained in Revision 18 of RG 1.147.
    Public comments on N-576-2 requested that the NRC revise the 
proposed condition to follow IWA-4200 in their code of record. In 
response, the NRC revised the ``note'' in the condition in Revision 18 
of RG 1.147 to eliminate the portion regarding reconciliation. The 
revised ``note'' will read: ``Note: Steam generator tube repair methods 
require prior NRC approval through the Technical Specifications. This 
Code Case does not address certain aspects of this repair, e.g., the 
qualification of the inspection and plugging criteria necessary for 
staff approval of the repair method.''

[[Page 2337]]

Code Case N-593-2 [Supplement 8, 2010 Edition]
    Type: Revised.
    Title: Examination Requirements for Steam Generator Nozzle-to-
Vessel Welds, Section XI, Division 1.
    The first condition on Code Case N-593-2 is identical to the 
condition on Code Case N-593 that was first approved by the NRC in 
Revision 13 of RG 1.147 in June 2003. The condition stated that, 
``Essentially 100 percent (not less than 90 percent) of the examination 
volume A-B-C-D-E-F-G-H [in Figure 1 of the Code Case] must be 
examined.'' The reasons for imposing this condition in Code Case N-593 
continue to apply to Code Case N-593-2. Therefore, this condition has 
been retained for this Code Case in Revision 18 of RG 1.147.
    The second condition on Code Case N-593-2 is new. Revision 2 of the 
Code Case reduces the weld examination volume by reducing the width 
examined on either side of the weld from ts/2 to \1/2\ in. 
The basis for this change in inspection volume is to revise the 
examination volume for steam generator nozzle[dash]to[dash]vessel welds 
(under Code Case N-593-2) to be consistent with that specified in Code 
Case N-613-1 for similar vessel nozzles.
    The NRC identified an issue with respect to Code Case N-593-2 
regarding its inconsistency with Code Case N-613-1. Code Case N-593-2 
and Code Case N-613-1 address certain types of nozzle-to-vessel welds. 
Code Case N-613-1 states that ``. . . Category B-D nozzle-to-vessel 
welds previously ultrasonically examined using the examination volumes 
of Figs. IWB-2500-7(a), (b), and (c) may be examined using the reduced 
examination volume (A-B-C-D-E-F-G-H) of Figs. 1, 2, and 3.'' The 
keywords are ``previously examined.'' Code Case N-613-1 requires the 
larger volume to have been previously examined before examinations 
using the reduced volume can be performed. This ensures that there are 
no detrimental flaws in the component adjacent to the weld that would 
be missed if the inspection was performed only on the reduced volume. 
However, Code Case N-593-2 allows a licensee to immediately implement 
the reduced volume. Accordingly, the NRC is approving Code Case N-593-2 
with a condition to require that the examination volume specified in 
Section XI, Table IWB-2500-1, Examination Category B-D, be used for the 
examination of steam generator nozzle[dash]to[dash]vessel welds at 
least once prior to use of the reduced volume, as allowed by the Code 
Case.
Code Case N-638-6 [Supplement 6, 2010 Edition]
    Type: Revised.
    Title: Similar and Dissimilar Metal Welding Using Ambient 
Temperature Machine GTAW Temper Bead Technique, Section XI, Division 1.
    Code Case N-638-6 allows the use of the automatic or machine gas-
tungsten arc welding (GTAW) temper bead technique. The GTAW is a proven 
method that can produce high-quality welds because it affords greater 
control over the weld area than many other welding processes.
    The NRC first approved Code Case N-638 (Revision 0) in 2003 
(Revision 13 of RG 1.147). Code Case N-638-4 was approved by the NRC in 
Revision 16 of RG 1.147 with two conditions. Code Case N-638-5 was not 
approved in RG 1.147 for generic use but has been approved through 
requests for an alternative to Sec.  50.55a. Code Case N-638-6 resolves 
one of the NRC's concerns that were raised when Code Case N-638-4 was 
considered for approval and, therefore, the NRC is deleting that 
condition from RG 1.147.
    Many of the provisions for developing and qualifying welding 
procedure specifications for the temper bead technique that were 
contained in earlier versions of the Code Case have been incorporated 
into ASME Section IX, ``Welding and Brazing Qualifications,'' QW-290, 
``Temper Bead Welding.'' Code Case N-638-6 retains the provisions not 
addressed by QW-290 and references QW-290 in lieu of specifying them 
directly in the Code Case.
    In addition to retaining one of the two conditions on Code Case N-
638-4, the NRC considered adding a new condition to address technical 
issues raised by certain provisions of Code Case N-638-6.
    The retained condition on Code Case N-638-6 pertains to the 
qualification of nondestructive evaluation (NDE) and is identical to 
the condition on N-638-4 that was approved by the NRC in Revision 17 of 
RG 1.147 in October 2014. The reasons for imposing this condition in 
Code Case N-638 continue to apply to N-638-6. Therefore, this condition 
has been retained in Revision 18 of RG 1.147.
    The new proposed condition (2) states that section 1(b)(1) of the 
Code Case shall not be used. Section 1(b)(1) would allow through-wall 
circumferential repair welds to be made using the temper bead technique 
without heat treatment. Revisions 1 through 5 of N-638 limited the 
depth of the weld to one-half of the ferritic base metal thickness and 
the previously stated condition will limit repairs to this previously 
approved value. Repairs exceeding one-half of the ferritic base metal 
thickness may represent significant repairs (e.g., replacement of an 
entire portion of the reactor coolant loop). At the time that this 
revision of the Code Case was approved by ASME, the NRC staff had 
concerns related to through-wall repairs. Subsequently, through further 
evaluation related to a separate rulemaking, the NRC resolved its 
concerns related to through-wall repairs. Therefore, the NRC determined 
that proposed Condition (2) is unnecessary and has removed this 
condition from the final RG 1.147, Revision 18.
Code Case N-662-1 [Supplement 6, 2010 Edition]
    Type: Revised.
    Title: Alternative Repair/Replacement Requirements for Items 
Classified in Accordance with Risk-Informed Processes, Section XI, 
Division 1.
    The condition on Code Case N-662-1 is identical to the condition on 
N-662 that was approved by the NRC in Revision 16 of RG 1.147 in 
October 2010. The reasons for imposing this condition were not resolved 
by Code Case N-662-1. Therefore, this condition has been retained for 
this Code Case in Revision 18 of RG 1.147.
Code Case N-666-1 [Supplement 9, 2010 Edition]
    Type: Revised.
    Title: Weld Overlay of Classes 1, 2, and 3 Socket Welded 
Connections, Section XI, Division 1.
    Code Case N-666 was unconditionally approved in Revision 17 of RG 
1.147. The NRC approves Code Case N-666-1 with one condition.
    The condition is that a surface examination must be performed on 
the completed weld overlay for Class 1 and Class 2 piping socket welds. 
Code Case N-666-1 contains provisions for the design, installation, 
evaluation, pressure testing, and examination of the weld overlays on 
Class 1, 2, and 3 socket welds. Section 5(a)(1) of the Code Case 
requires NDE of the completed weld overlay in accordance with the 
Construction Code. However, various Construction Codes have been used 
in the design and fabrication of the nuclear power plant fleet. The 
requirements for NDE have changed over the years, as more effective and 
reliable methods and techniques have been developed. In addition, 
Construction Code practices have evolved based on design and 
construction experience. The NRC is concerned that some of the 
Construction

[[Page 2338]]

Codes would not require a surface examination of the weld overlay and 
would, therefore, be inadequate for NDE of the completed weld overlay. 
The NRC believes that a VT-1 examination alone would not be adequate 
and that a surface or volumetric examination must be performed on the 
completed weld overlay for Class 1 and Class 2 piping socket welds. 
Fabrication defects must be dispositioned using the surface or 
volumetric examination criteria of the Construction Code, as identified 
in the Repair/Replacement Plan.
    Public commenters requested that the words ``and seal weld'' be 
removed from the condition because the phrase implies that the seal 
weld requires surface examination in addition to surface examination of 
the final overlay. The Code Case requires a visual examination of the 
seal weld, remaining socket weld, and adjacent base material before the 
weld overlay can be applied, which the NRC has determined is the 
appropriate examination prior to the application of the weld overlay. 
Therefore, proposed Condition (1) has been revised to remove ``and seal 
weld.''
    In the proposed rule, the NRC included a second condition, which 
required that if a surface or volumetric examination of the completed 
weld overlay was not required by the plant-specific Construction Code, 
that a VT-1 visual examination be performed of the weld overlay. 
Paragraph 5(a) of the Code Case requires ``visual and nondestructive 
examination of the final structural overlay weld.'' Paragraph 5(a)(1) 
of the Code Case specifically requires a VT-1 visual examination of the 
completed weld overlay. Public commenters requested that the NRC remove 
the second condition because it was redundant and unnecessary. The NRC 
staff agrees and thus Condition (2) has been removed from the final 
rule.
Code Case N-749 [Supplement 9, 2010 Edition]
    Type: New.
    Title: Alternative Acceptance Criteria for Flaws in Ferritic Steel 
Components Operating in the Upper Shelf Temperature Range, Section XI, 
Division 1.
    The NRC has determined that instead of the upper shelf transition 
temperature, Tc, as defined in the Code Case, the following 
shall be used:

Tc = 154.8 [deg]F + 0.82 x RTNDT (in U.S 
Customary Units), and
Tc = 82.8 [deg]C + 0.82 x RTNDT (in International 
System (SI) Units).

    Tc is the temperature above which the elastic plastic 
fracture mechanics (EPFM) method must be applied. Additionally, the NRC 
defines temperature Tc1 below, which the linear elastic 
fracture mechanics (LEFM) method must be applied:

Tc1 = 95.36 [deg]F + 0.703 x RTNDT (in U.S 
Customary Units), and
Tc1 = 47.7 [deg]C + 0.703 x RTNDT (in 
International System (SI) Units).

    Between Tc1 and Tc, while the fracture mode 
is in transition from LEFM to EPFM, users should consider whether or 
not it is appropriate to apply the EPFM method. Alternatively, the 
licensee may use a different Tc value, if it can be 
justified by plant[dash]specific Charpy curves.
    Code Case N-749 provides acceptance criteria for flaws in ferritic 
components for conditions when the material fracture resistance will be 
controlled by upper-shelf toughness behavior. These procedures may be 
used to accept a flaw in lieu of the requirements in Section XI, 
paragraphs IWB-3610 and IWB-3620, which use LEFM to evaluate flaws that 
exceed limits of Section XI, paragraph IWB-3500. Code Case N-749 
employs EPFM methods (J[dash]integral) and is patterned after the 
fracture methodology and acceptance criteria that currently exist in 
Section XI, paragraph IWB-3730(b), and Section XI, Nonmandatory 
Appendix K, ``Assessment of Reactor Vessels with Upper Shelf Charpy 
Impact Energy Levels.'' The Code Case states that the proposed 
methodology is applicable if the metal temperature of the component 
exceeds the upper shelf transition temperature, Tc, which is 
defined as nil-ductility reference temperature (RTNDT) plus 
105 degrees F. The justification for this, as documented in the 
underlying White Paper, PVP2012-78190, ``Alternative Acceptance 
Criteria for Flaws in Ferritic Steel Components Operating in the Upper 
Shelf Temperature Range,'' is that the ASME BPV Code, Section XI, 
K1c curve will give a (T- RTNDT) value of 105 
degrees F at K1c of 200 ksi[radic]inch.
    Defining an upper shelf transition temperature purely based on LEFM 
data is not convincing because it ignores EPFM data and Charpy data and 
their relationship to the LEFM data. The NRC staff performed 
calculations on several randomly selected reactor pressure vessel 
surveillance materials with high upper-shelf energy values and low 
RTNDT values from three plants and found that using 
Tc, as defined in the Code Case, is nonconservative because 
at the temperature of RTNDT + 105 degrees F, the Charpy 
curves show that most of the materials will not reach their respective 
upper-shelf energy levels. The NRC staff's condition is based on a 2015 
ASME Pressure Vessels and Piping Conference paper (PVP2015-45307) by 
Mark Kirk, Gary Stevens, Marjorie Erickson, William Server, and Hal 
Gustin entitled, ``Options for Defining the Upper Shelf Transition 
Temperature (Tc) for Ferritic Pressure Vessel Steels,'' where 
Tc and Tc1 are defined as the intersections of 
specific toughness curves of LEFM data and EPFM data, as shown in that 
paper. Using the model in the 2015 PVP paper is justified because, in 
addition to its theoretically motivated approach in applying the 
temperature-dependent flow behavior of body-centered cubic materials, 
the model is also supported by numerous LEFM data and 809 EPFM data in 
the upper shelf region.
    While the Tc proposed in Code Case N-749 is conservative 
based on the intersection of the mean curves of the two sets of data, 
the NRC determined that actual or bounding properties (on the 
conservative side) should be used instead of mean material properties 
for evaluating flaws detected in a ferritic component using the EPFM 
approach. This will prevent inaccurate component failure predictions 
using the EPFM approach, due to overestimated material properties. 
Further, the NRC's approach considers the temperature range for 
fracture mode transition between LEFM and EPFM. Based on the previous 
discussion, the NRC is imposing a condition on the use of Code Case N-
749 that: (1) The two equations for Tc be used instead of 
Tc, as proposed in the Code Case for requiring EPFM 
application, when the temperature is above Tc, and (2) the 
two equations for Tc1 be used for requiring LEFM application 
when temperature is below Tc1. Between Tc1 and 
Tc, while the fracture mode is in transition between LEFM 
and EPFM, users should consider whether or not it is appropriate to 
apply the EPFM method.
    Alternatively, the licensee may use a different Tc 
value, if it can be justified by plant-specific Charpy curves.
Code Case N-754 [Supplement 6, 2010 Edition]
    Type: New.
    Title: Optimized Structural Dissimilar Metal Weld Overlay for 
Mitigation of PWR Class 1 Items, Section XI, Division 1.
    The NRC approves Code Case N-754 with three conditions. Code Case 
N-754 provides requirements for installing optimized structural weld 
overlays (OWOL) on the outside surface of ASME Class 1 heavy-wall, 
large-diameter piping composed of ferritic, austenitic stainless steel, 
and nickel based alloy materials in pressurized water reactors

[[Page 2339]]

(PWRs) as a mitigation measure, where no known defect exists or the 
defect depth is limited to 50 percent through wall. The upper 25 
percent of the original pipe wall thickness is credited as a part of 
the OWOL design in the analyses performed, in support of these repairs. 
The technical basis supporting the use of OWOLs is provided in the 
Electric Power Research Institute (EPRI) Materials Reliability Project 
(MRP) Report MRP-169, Revision 1-A, entitled, ``Technical Basis for 
Preemptive Weld Overlays for Alloy 82/182 Butt Welds in PWRs.'' By 
letter dated August 9, 2010 (ADAMS Accession No. ML101620010), the NRC 
informed the Nuclear Energy Institute (NEI) that the staff found that 
MRP-169, Revision 1, as revised by letter dated February 3, 2010, 
adequately described: (1) Methods for the weld overlay design; (2) the 
supporting analyses of the design; (3) the experiments that verified 
the analyses; and (4) the inspection requirements of the dissimilar 
metal welds to be overlaid. However, the NRC identified the following 
conditions.
    The first condition requires that the conditions imposed on the use 
of OWOLs contained in the NRC final safety evaluation for MRP-169, 
Revision 1-A, must be satisfied. Eighteen limitations and conditions 
are described in the final safety evaluation that address issues such 
as fatigue crack growth rates, piping loads, design life of the weld 
overlay, and reexamination frequencies. The imposition of the 
conditions in the safety evaluation provide reasonable assurance that 
the structural integrity of the pipes repaired through the use of weld 
overlays will be maintained.
    Code Case N-754 references Code Case N-770-2, ``Alternative 
Examination Requirements and Acceptance Standards for Class 1 Pressure 
Water Reactor (PWR) Piping and Vessel Nozzle Butt Welds Fabricated With 
UNS N06082 or UNS W86182 Weld Filler Material With or Without 
Application of Listed Mitigation Activities, Section XI, Division 1.'' 
The reference to Code Case N-770-2 provides the ASME requirements for 
the performance of the preservice and ISI examinations of OWOLs, with 
additional requirements if the ultrasonic examination is qualified for 
axial flaws. The NRC approved Code Case N-770-2 with conditions in 
Sec.  50.55a(g)(6)(ii)(F) on July 18, 2017 (82 FR 32934). Accordingly, 
the second condition on the use of Code Case N-754 is that the 
preservice and inservice inspections of OWOLs must satisfy Sec.  
50.55a(g)(6)(ii)(F), i.e., meet the provisions of Code Case N-770-2.
    The third condition addresses a potential implementation issue in 
Code Case N-754 with respect to the deposition of the first layer of 
weld metal. The second sentence in paragraph 1.2(f)(2) states that 
``The first layer of weld metal deposited may not be credited toward 
the required thickness, but the presence of this layer shall be 
considered in the design analysis requirements in 2(b).'' The NRC found 
that, among licensees, there can be various interpretations of the 
words used in the ASME BPV Code and Code Cases. In this instance, the 
NRC determined that the word ``may'' needed to be changed to ``shall'' 
in the second sentence in paragraph 1.2(f)(2), as a condition for use 
of this Code Case. Accordingly, the NRC is adding a third condition to 
clarify that the first layer shall not be credited toward the required 
OWOL thickness unless the chromium content of the first layer is at 
least 24 percent.
Code Case N-778 [Supplement 6, 2010 Edition]
    Type: New.
    Title: Alternative Requirements for Preparation and Submittal of 
Inservice Inspection Plans, Schedules, and Preservice and Inservice 
Summary Reports, Section XI, Division 1.
    The NRC is approving Code Case N-778 with two conditions. Section 
XI, paragraph IWA-1400(d), in the editions and addenda currently used 
by the operating fleet, requires licensees to submit plans, schedules, 
and preservice and ISI summary reports to the enforcement and 
regulatory authorities having jurisdiction at the plant site. In the 
licensees' pursuit to decrease burden, they have alluded to the 
resources associated with the requirement to submit the items 
previously listed. Code Case N-778 was developed to provide an 
alternative to the requirements in the ASME BPV Code, in that the items 
previously listed would only have to be submitted if specifically 
required by the regulatory and enforcement authorities.
    The NRC reviewed its needs with respect to the submittal of the 
subject plans, schedules, and reports, and determined that it is not 
necessary to require the submittal of plans and schedules. The NRC made 
this determination because the latest up[dash]to[dash]date plans and 
schedules are available at the plant site and can be requested by the 
NRC at any time. However, the NRC determined that summary reports still 
need to be submitted. Summary reports provide valuable information 
regarding examinations that have been performed, conditions noted 
during the examinations, the corrective actions performed, and the 
status of the implementation of the ISI program. Accordingly, the NRC 
is approving Code Case N-778 with conditions to require that licensees 
continue to submit summary reports in accordance with paragraph IWA-
6240 of the 2009 Addenda of ASME Section XI, as addressed below.
    The two conditions are modeled on the requirements currently in 
paragraph IWA-6240 of the 2009 Addenda, Section XI. The requirements in 
Section XI do not specify when the reports are to be submitted to the 
regulatory authority; rather, the requirements only state that the 
reports shall be completed. The first condition requires that the 
preservice inspection summary report be submitted before the date of 
placement of the unit into commercial service. The second condition 
requires that the ISI summary report be submitted within 90 calendar 
days of the completion of each refueling outage. The conditions rely on 
the date of commercial service and the completion of a refueling outage 
to determine when the reports are needed to be submitted to the 
regulatory authority.
Code Case N-789 [Supplement 6, 2010 Edition]
    Type: New.
    Title: Alternative Requirements for Pad Reinforcement of Class 2 
and 3 Moderate[dash]Energy Carbon Steel Piping for Raw Water Service, 
Section XI, Division 1.
    The NRC is approving Code Case N-789 with one condition. For 
certain types of degradation, the Code Case provides requirements for 
the temporary repair of degraded moderate energy Class 2 and Class 3 
piping systems by external application of welded reinforcement pads. 
The Code Case does not require inservice monitoring for the pressure 
pad. However, the NRC determined that it is unacceptable to not monitor 
the pressure pad because there may be instances where an unexpected 
corrosion rate may cause the degraded area in the pipe to expand beyond 
the area that is covered by the pressure pad. This could lead to the 
pipe leaking and may challenge the structural integrity of the repaired 
pipe. Therefore, the NRC is approving Code Case N-789 with a condition 
to require a monthly visual examination of the installed pressure pad 
for evidence of leakage.
    In the proposed rule, the NRC expressed concern that the corrosion 
rate specified in paragraph 3.1(1) of the Code Case may not address 
certain scenarios. That paragraph would allow

[[Page 2340]]

either a corrosion rate of two times the actual measured corrosion rate 
at the reinforcement pad installation location or four times the 
estimated maximum corrosion rate for the system. To ensure that a 
conservative corrosion rate is used to provide sufficient margin, the 
NRC considered adding a second condition that requires that the design 
of the pressure pad use the higher of the two corrosion rates 
calculated, based on the same degradation mechanism as the degraded 
location. However, as a result of a public comment, the NRC 
reconsidered and determined that using a corrosion rate of either two 
times the actual measured corrosion rate in that location, or four 
times the estimated maximum corrosion rate for the system, already 
provides a sufficiently conservative estimate of the corrosion rate; 
therefore, a condition is not needed.
Code Case N-795 [Supplement 3, 2010 Edition]
    Type: New.
    Title: Alternative Requirements for BWR Class 1 System Leakage Test 
Pressure Following Repair/Replacement Activities, Section XI, Division 
1.
    The NRC is approving Code Case N-795 with two conditions. The first 
condition addresses a prohibition against the production of heat 
through the use of a critical reactor core to raise the temperature of 
the reactor coolant and pressurize the reactor coolant pressure 
boundary (RCPB) (sometimes referred to as nuclear heat). The second 
condition addresses the duration of the hold time when testing non-
insulated components to allow potential leakage to manifest itself 
during the performance of system leakage tests.
    Code Case N-795 was intended to address concerns that performing 
the ASME-required pressure test for boiling water reactors (BWRs) under 
shutdown conditions, (1) places the unit in a position of significantly 
reduced margin, approaching the fracture toughness limits defined in 
the Technical Specification Pressure[dash]Temperature (P-T) curves, and 
(2) requires abnormal plant conditions/alignments, incurring additional 
risks and delays, while providing little added benefit beyond tests, 
which could be performed at slightly reduced pressures under normal 
plant conditions. However, due to restrictions imposed by the pressure 
control systems, most BWRs cannot obtain reactor pressure corresponding 
to 100 percent rated power during normal startup operations at low 
power levels that would be conducive to performing examinations for 
leakage. The alternative test, provided by Code Case N-795, would be 
performed at slightly reduced pressures and normal plant conditions, 
which the NRC finds will constitute an adequate leak examination and 
would reduce the risk associated with abnormal plant conditions and 
alignments.
    However, the NRC has had a long-standing prohibition against the 
production of heat through the use of a critical reactor core to raise 
the temperature of the reactor coolant and pressurize the RCPB. A 
letter dated February 2, 1990, from James M. Taylor, Executive Director 
for Operations, NRC, to Messrs. Nicholas S. Reynolds and Daniel F. 
Stenger, Nuclear Utility Backfitting and Reform Group (ADAMS Accession 
No. ML14273A002), established the NRC position with respect to use of a 
critical reactor core to raise the temperature of the reactor coolant 
and pressurize the RCPB. In summary, the NRC's position is that testing 
under these conditions involves serious impediments to careful and 
complete inspections, and therefore, inherent uncertainty with regard 
to assuring the integrity of the RCPB. Further, the practice is not 
consistent with basic defense-in-depth safety principles.
    The NRC's position established in 1990, was reaffirmed in 
Information Notice No. 98-13, ``Post-Refueling Outage Reactor Pressure 
Vessel Leakage Testing Before Core Criticality,'' dated April 20, 1998. 
The Information Notice was issued in response to a licensee that had 
conducted an ASME BPV Code, Section XI, leakage test of the reactor 
pressure vessel and subsequently discovered that it had violated 10 CFR 
part 50, appendix G, IV.A.2.d. This regulation states that pressure 
tests and leak tests of the reactor vessel that are required by Section 
XI of the ASME Code must be completed before the core is critical. The 
Information Notice references NRC Inspection Report 50-254/97-27 (ADAMS 
Accession No. ML15216A276), which documents that licensee personnel 
performing VT-2 examinations of the drywell at one BWR plant covered 50 
examination areas in 12 minutes, calling into question the adequacy of 
the VT-2 examinations.
    The bases for the NRC's historical prohibition of pressure testing 
with the core critical can be summarized as follows:
    1. Nuclear operation of a plant should not commence before 
completion of system hydrostatic and leakage testing to verify the 
basic integrity of the RCPB, a principal defense-in-depth barrier to 
the accidental release of fission products. In accordance with the 
defense-in-depth safety precept, the nuclear power plant design 
provides for multiple barriers to the accidental release of fission 
products from the reactor.
    2. Hydrotesting must be done essentially water solid (i.e., free of 
pockets of air, steam or other gases) so that stored energy in the 
reactor coolant is minimized during a hydrotest or leaktest.
    3. The elevated reactor coolant temperatures, associated with 
critical operation, result in a severely uncomfortable and difficult 
working environment in plant spaces where the system leakage 
inspections must be conducted. The greatly increased stored energy in 
the reactor coolant, when the reactor is critical, increases the hazard 
to personnel and equipment in the event of a leak. As a result, the 
ability for plant workers to perform a comprehensive and careful 
inspection becomes greatly diminished.
    However, the NRC staff has determined that pressure testing with 
the core critical is acceptable, if performed after repairs of a 
limited scope, where only a few locations or a limited area needs to be 
examined, and when ASME Code Section XI, Table IWB-2500-1, Category B-P 
(the pressure test required once per cycle of the entire RCPB), has 
been recently performed, thus verifying the integrity of the overall 
RCPB. The NRC also notes that Code Case N-795 does not allow for the 
use of the alternative test pressure following repairs/replacements on 
the RPV, therefore it does not violate 10 CFR part 50, Appendix G. The 
NRC determined that the risk associated with nuclear heat at low power 
is comparable with the risk to the plant, when the test is performed 
without nuclear heat (with the core subcritical) during mid-cycle 
outages, when decay heat must be managed. Performing the pressure test 
under shutdown conditions at full operating pressure without nuclear 
heat requires securing certain key pressure control, heat removal, and 
safety systems. Under such conditions, it is more difficult to control 
temperature and pressure, when there is significant decay heat 
production, such as after a mid-cycle outage, which may reduce the 
margin available to prevent exceeding the plant pressure-temperature 
limits.
    The scope of repairs should be relatively small, when the pressure 
test is conducted using nuclear heat, in order to minimize the 
personnel safety risk and to avoid rushed examinations. Code Case N-795 
does not place any restrictions on the size or scope of the repairs for 
which the alternative may be used, other than the alternative test 
pressure may not be used to satisfy

[[Page 2341]]

pressure test requirements following repair/replacement activities on 
the reactor vessel. It is impractical to specify a particular number of 
welded or mechanical repairs that would constitute a ``limited scope.'' 
However, if the plant is still in a refueling outage and has already 
performed the ASME Section XI Category B-P pressure test of the entire 
RCPB, it is likely that subsequent repairs would be performed only on 
an emergent basis, and would generally be of a limited scope. 
Additionally, the overall integrity of the RCPB will have been recently 
confirmed via the Category B-P test. For mid-cycle maintenance outages, 
the first condition allows the use of nuclear heat to perform the test, 
if the outage duration is fourteen (14) days or less. This would tend 
to limit the scope of repairs, and also limit use of the Code Case to 
outages when decay heat was a significant problem. Therefore, the first 
condition on Code Case N-795 states:

``The use of nuclear heat to conduct the BWR Class 1 system leakage 
test is prohibited (i.e., the reactor must be in a non-critical 
state), except during refueling outages in which the ASME Section XI 
Category B-P pressure test has already been performed, or at the end 
of mid-cycle maintenance outages fourteen (14) days or less in 
duration.''

    With respect to the second condition and adequate pressure test 
hold time, the technical analysis supporting Code Case N-795 indicates 
that the lower test pressure provides more than 90 percent of the flow, 
which would result from the pressure corresponding to 100 percent 
power. However, a reduced pressure means a lower leakage rate, so 
additional time is required in order for there to be sufficient leakage 
to be observed by inspection personnel. Section XI, paragraph IWA-5213, 
``Test Condition Holding Time,'' does not require a holding time for 
Class 1 components, once test pressure is obtained. To account for the 
reduced pressure, Code Case N-795 would require a 15-minute hold time 
for non-insulated components. The NRC has determined that 15 minutes 
does not allow for an adequate examination, because it is not possible 
to predict the entire range of scenarios or types of defects that could 
result in leakage. While some types of defects could result in 
immediate leakage, such as an improperly torqued bolted connection; 
other types of defects, such as weld defects or tight cracks could 
represent a more torturous path for leakage and may result in delayed 
leakage. The staff determined that, due to the uncertainty in the time 
required for leakage to occur to an extent, it would be readily 
detectable by visual examination, hence, it is appropriate to 
conservatively specify a longer hold time of 1 hour for non-insulated 
components. Therefore, the final rule retains the one hour hold time 
for non-insulated components.
Code Case N-799 [Supplement 4, 2010 Edition]
    Type: New.
    Title: Dissimilar Metal Welds Joining Vessel Nozzles to Components, 
Section XI, Division 1.
    The NRC approves Code Case N-799 with four conditions. Code Case N-
799 is a new Code Case developed to provide examination requirements 
for the steam generator primary nozzle to pump casing attachment weld 
for AP-1000 plants and dissimilar metal welds joining vessel nozzles to 
pumps used in recent reactor designs (e.g., AP-1000, Advanced BWR). 
Nuclear power plant pump casings are typically manufactured from cast 
austenitic stainless steel (CASS) materials. The NRC is approving the 
Code Case with conditions to address the shortcomings in the Code Case 
with respect to requirements for ultrasonic examination.
    The CASS is an anisotropic and inhomogeneous material. The 
manufacturing process can result in varied and mixed structures. The 
large size of the anisotropic grains affects the propagation of 
ultrasound by causing severe attenuation, changes in velocity, and 
scattering of ultrasonic energy. Refraction and reflection of the sound 
beam occurs at the grain boundaries, which can result in specific 
volumes of material not being examined, or defects being missed or 
mischaracterized. The grain structure of the associated weldments also 
impacts the effectiveness and reliability of the examinations. 
Accordingly, it is paramount that robust examination techniques be 
used.
    Research has been conducted by several domestic and international 
organizations attempting to address the shortcomings associated with 
the use of conventional methods for the inspection of CASS materials. 
The results of a study at Pacific Northwest National Laboratory (PNNL) 
were published in NUREG/CR-6933, ``Assessment of Crack Detection in 
Heavy-Walled Cast Stainless Steel Piping Welds Using Advanced Low-
Frequency Ultrasonic Methods'' (ADAMS Accession No. ML071020409). The 
study demonstrated that additional measures were required to reliably 
detect and characterize flaws in CASS materials and their associated 
weldments.
    Performance demonstration requirements for CASS components and 
associated weldments have not yet been developed by the industry. To 
ensure that effective and reliable examinations are performed, the NRC 
is adopting the following four conditions on the Code Case.
    The first condition addresses the gap between the probe and 
component surface. Industry experience shows that effective ultrasonic 
examinations depend, to a great extent, on limiting the gap between the 
probe and component surface to less than 0.032[dash]inch. The BPV Code 
does not have any requirements with respect to surface smoothness and 
waviness. It has been demonstrated that reduced coupling and probe 
lift-off on ``rough'' surfaces have the potential to present a 
scattering effect at an interface where an acoustic beam impinges, to 
redirect and mode convert some energy, which when returned to the probe 
can be the source of spurious signals, or cause flaws to be mis-
characterized or missed altogether. Accordingly, the first condition 
requires that the scanning surfaces have a gap less than 0.032-inch 
beneath the ultrasonic testing probe. Gaps greater than 0.032[dash]inch 
must be considered to be unexamined, unless it can be demonstrated, on 
representative mockups, that a Section XI, Appendix VIII, Supplement 
10, demonstration can be passed.
    The second condition (No. 2a in DG-1296) is that the examination 
requirements of Section XI, Mandatory Appendix I, paragraph I-3200(c) 
must be applied. Code Case N-799 does not contain specific requirements 
regarding examination techniques. Paragraph I-3200(c) contains specific 
requirements that can be applied.
    The third condition (No. 2c in DG-1296) is that ultrasonic depth 
and sizing qualifications for CASS components must use the ASME BPV 
Code requirements in Section XI, Appendix VIII, Supplement 10. 
Supplement 10 contains qualification requirements for dissimilar metal 
welds, and the use of these requirements will ensure that robust 
techniques are applied.
    The fourth condition (No. 2e in DG-1296) is that cracks that are 
detected but cannot be depth-sized with performance-based procedures, 
equipment, and personnel qualifications consistent with ASME Code 
Section XI, Appendix VIII, shall be repaired or removed.
OM Code Cases (RG 1.192)
Code Case OMN-1, Revision 1 [2012 Edition]
    Type: Revised.
    Title: Alternative Rules for Preservice and Inservice Testing of 
Active Electric

[[Page 2342]]

Motor[dash]Operated Valve Assemblies in Light-Water Reactor Power 
Plants.
    The conditions on Code Case OMN-1, Revision 1 [2012 Edition] are 
identical to the conditions on OMN-1 [2006 Addenda] that were approved 
by the NRC in Revision 1 of RG 1.192 in October 2014. The reasons for 
imposing these conditions are not resolved by Code Case OMN-1, Revision 
1 [2012 Edition] and, therefore, these conditions have been retained in 
Revision 2 of RG 1.192.
Code Case OMN-3 [2012 Edition]
    Type: Reaffirmed.
    Title: Requirements for Safety Significance Categorization of 
Components Using Risk Insights for Inservice Testing of LWR Power 
Plants.
    The conditions on Code Case OMN-3 [2012 Edition] are identical to 
the conditions on OMN-3 [2004 Edition] that were approved by the NRC in 
Revision 1 of RG 1.192 in October 2014. The reasons for imposing these 
conditions are not resolved by Code Case OMN-3 [2012 Edition] and, 
therefore, these conditions have been retained in Revision 2 of RG 
1.192.
Code Case OMN-4 [2012 Edition]
    Type: Reaffirmed.
    Title: Requirements for Risk Insights for Inservice Testing of 
Check Valves at LWR Power Plants.
    The conditions on Code Case OMN-4 [2012 Edition] are identical to 
the conditions on OMN-4 [2004 Edition] that were approved by the NRC in 
Revision 1 of RG 1.192 in October 2014. The reasons for imposing these 
conditions are not resolved by Code Case OMN-4 [2012 Edition] and, 
therefore, these conditions have been retained in Revision 2 of RG 
1.192.
Code Case OMN-9 [2012 Edition]
    Type: Reaffirmed.
    Title: Use of a Pump Curve for Testing.
    The conditions on Code Case OMN-9 [2012 Edition] are identical to 
the conditions on OMN-9 [2004 Edition] that were approved by the NRC in 
Revision 1 of RG 1.192 in October 2014. The reasons for imposing these 
conditions are not resolved by Code Case OMN-9 [2012 Edition] and, 
therefore, these conditions have been retained in Revision 2 of RG 
1.192.
Code Case OMN-12 [2012 Edition]
    Type: Reaffirmed.
    Title: Alternative Requirements for Inservice Testing Using Risk 
Insights for Pneumatically and Hydraulically Operated Valve Assemblies 
in Light-Water Reactor Power Plants (OM-Code 1998, Subsection ISTC).
    The conditions on Code Case OMN-12 [2012 Edition] are identical to 
the conditions on OMN-12 [2004 Edition] that were approved by the NRC 
in Revision 1 of RG 1.192 in October 2014. The reasons for imposing 
these conditions are not resolved by Code Case OMN-12 [2012 Edition] 
and, therefore, these conditions have been retained in Revision 2 of RG 
1.192.
Code Case OMN-16, Revision 1 [2012 Edition]
    Type: Revised.
    Title: Use of a Pump Curve for Testing.
    Code Case OMN-16, 2006 Addenda, was approved by the NRC in 
Regulatory Guide 1.192, Revision 1. With respect to Code Case OMN-16, 
Revision 1, 2012 Edition, there was an editorial error in the 
publishing of this Code Case in that Figure 1 from the original Code 
Case (i.e., Rev. 0, 2006 Addenda) was omitted. Accordingly, the NRC 
approves OMN-16, Revision 1, with a condition requiring that Figure 1 
from the original Code Case be used when implementing OMN-16, Revision 
1.
Code Case OMN-18 [2012 Edition]
    Type: Reaffirmed.
    Title: Alternate Testing Requirements for Pumps Tested Quarterly 
Within 20% of Design Flow.
    The ASME OM Code defines Group A pumps as those pumps that are 
operated continuously or routinely during normal operation, cold 
shutdown, or refueling operations. The OM Code specifies that each 
Group A pump undergoes a Group A test quarterly and a comprehensive 
test biennially. The OM Code requires that the reference value for a 
comprehensive test to be within 20 percent of pump design flow, while 
the reference value for a Group A test needs to be within 20 percent of 
the pump design flow, if practicable. The biennial comprehensive test 
was developed (first appeared in the 1995 Edition of the OM Code) 
because pump performance concerns demonstrated that more stringent 
periodic testing was needed at a flow rate within a more reasonable 
range of the pump design flow rate, than typically performed during the 
pump IST in the past.
    Currently, when performing either the quarterly Group A test or the 
biennial comprehensive pump test, licensees must comply with certain 
limits for the flow Acceptable Range, the flow Required Action Range, 
the differential pressure (or discharge pressure) Acceptable Range, and 
the differential pressure (or discharge pressure) Required Action 
Range. The limits for the quarterly Group A test are obtained by using 
a factor of 1.10 times the flow reference value (Qr) or the 
differential or discharge pressure reference value 
([Delta]Pr or Pr), as applicable to the pump 
type. The limits for the biennial comprehensive pump test 
are obtained by using the factor of 1.03 times Qr or 
[Delta]Pr (or Pr), as applicable to the pump 
type, providing more restrictive test ranges and higher quality data.
    Code Case OMN-18, 2012 Edition, would remove the Code requirement 
to perform a biennial comprehensive pump test, where the quarterly 
Group A pump test is performed within 20 percent of the 
pump design flow rate, with instruments having the ability to obtain 
the accuracies required for the comprehensive pump test. The NRC finds 
the performance of a quarterly Group A pump test, at flow within 20 percent of the pump design flow rate, will be sufficient to 
detect mechanical and hydraulic degradation of the tested pump. The NRC 
finds that this will satisfy the intent of the biennial comprehensive 
pump test, with the exception that the test acceptable ranges and 
required action ranges are less precise than required for the 
comprehensive test. Therefore, the NRC approves Code Case OMN-18, 2012 
Edition, with a condition to specify the use of a factor of 1.06 for 
the Group A test parameters, to be consistent with the test ranges for 
the comprehensive test. The NRC concludes that the factor of 1.06 will 
provide a reasonable test range, when applying Code Case OMN-18 to 
Group A pumps tested quarterly, within 20 percent of the 
pump design flow rate. The NRC finds that the quarterly Group A test 
for pumps within 20 percent of the pump design flow rate, 
combined with the provisions in the Code Case OMN-18 for the pump 
instrumentation and the conditions in RG 1.192 for the test ranges, 
will provide reasonable assurance of the operational readiness of these 
pumps, as an acceptable alternative to the comprehensive pump test 
provisions in the ASME OM Code.
Code Case OMN-19 [2012 Edition]
    Type: Reaffirmed.
    Title: Alternative Upper Limit for the Comprehensive Pump Test.
    A requirement for a periodic pump verification test was added in 
Mandatory Appendix V, ``Pump Periodic Verification Test Program,'' to 
the 2012 Edition of the OM Code. The mandatory appendix is based on the 
determination by the ASME that a pump periodic verification test is 
needed to confirm that a pump can meet the required (differential or 
discharge) pressure as applicable, at its highest

[[Page 2343]]

design basis accident flow rate. Code Case OMN-19, 2012 Edition, would 
allow an applicant or licensee to use a multiplier of 1.06 times the 
reference value in lieu of the 1.03 multiplier for the comprehensive 
pump test's upper Acceptable Range criteria and Required Action Range, 
High criteria reference in the ISTB test acceptance criteria tables. 
The NRC considers Code Case OMN-19 to be acceptable where the 
provisions of Appendix V for a pump periodic verification test as 
referenced by ISTB-1400 are also satisfied to detect mechanical and 
hydraulic degradation. Therefore, the NRC approves Code Case OMN-19, 
2012 Edition, with the condition that the provisions in paragraph ISTB-
1400 and Mandatory Appendix V be applied when implementing the Code 
Case.
Code Case OMN-20 [2012 Edition]
    Type: New.
    Title: Inservice Testing Frequency.
    Surveillance Requirement (SR) 3.0.3 from Technical Specification 
(TS) 5.5.6, ``Inservice Testing Program,'' allows licensees to apply a 
delay period before declaring the SR for TS equipment ``not met,'' if a 
licensee inadvertently exceeds or misses the time limit for performing 
the TS surveillance. Licensees have been applying SR 3.0.3 to inservice 
tests performed in accordance with the ASME Codes. The NRC has 
determined that licensees cannot use TS 5.5.6 to apply SR 3.0.3 to 
inservice tests under Sec.  50.55a(f) that are not associated with a TS 
surveillance. To invoke SR 3.0.3, the licensee must first discover that 
a TS surveillance was not performed at its specified frequency. 
Therefore, the delay period that SR 3.0.3 provides does not apply to 
non[dash]TS support components tested under Sec.  50.55a(f). The OM 
Code does not provide for inservice test frequency reductions or 
extensions. In order to provide inservice test frequency reductions or 
extensions that cannot be provided by SR 3.0.3 from TS 5.5.6, ASME 
developed OM Code Case OMN-20. The NRC has reviewed OM Code Case OMN-20 
and has found it acceptable for use. The NRC determined that OM Code 
Case OMN-20 may be applied to editions and addenda of the OM Code that 
are listed in Sec.  50.55a(a)(1)(iv). Therefore, the NRC has included a 
condition in RG 1.192, specifying that Code Case OMN-20 is applicable 
to editions and addenda of the OM Code listed in Sec.  
50.55a(a)(1)(iv).

C. ASME Code Cases Not Approved for Use (RG 1.193)

    The ASME Code Cases that are currently issued by the ASME, but not 
approved for generic use by the NRC are listed in RG 1.193, ``ASME Code 
Cases not Approved for Use.'' In addition to the ASME Code Cases that 
the NRC has found to be technically or programmatically unacceptable, 
RG 1.193 includes Code Cases on reactor designs for 
high[dash]temperature gas[dash]cooled reactors and liquid metal 
reactors, reactor designs not currently licensed by the NRC, and 
certain requirements in Section III, Division 2, for submerged spent 
fuel waste casks, that are not endorsed by the NRC. Regulatory Guide 
1.193 complements RGs 1.84, 1.147, and 1.192; RG 1.193 confirms the 
Code Cases that are not approved for use. The NRC is not adopting any 
of the Code Cases listed in RG 1.193.

III. Opportunities for Public Participation

    The proposed rule and draft RGs were published in the Federal 
Register on March 2, 2016 (81 FR 10780), for a 75-day comment period. 
The public comment period closed on May 16, 2016.
    After the close of the public comment period, the NRC held a public 
meeting on August 22, 2016, to discuss the status of this proposed 
rule. The public meeting summary is available in ADAMS under Accession 
No. ML16265A001.

IV. Public Comment Analysis

    The NRC received a total of seven comment submissions on the 
proposed rule and draft RGs. Table III lists the commenters, their 
affiliation, and the ADAMS Accession Number for each submission.

                   Table III--Comment Submissions Received on the Proposed Rule and Draft RGs
----------------------------------------------------------------------------------------------------------------
                                                                                                ADAMS  accession
             Submission ID                     Commenter name              Affiliation                No.
----------------------------------------------------------------------------------------------------------------
1......................................  Paul Donavin.............  Private Citizen..........        ML16063A509
2......................................  Gregory Frederick and Dan  Electric Power Research          ML16126A524
                                          Patten.                    Institute.
3......................................  Anonymous................  Unknown..................        ML16133A422
4......................................  Charles Pierce...........  Southern Nuclear                 ML16137A857
                                                                     Operating Company.
5......................................  Ralph Hill III...........  ASME.....................        ML16138A835
6......................................  Mark Gowin...............  Private Citizen..........        ML16139A798
7......................................  David Helker.............  Exelon Generation                ML16153A432
                                                                     Company, LLC.
----------------------------------------------------------------------------------------------------------------

    The NRC reviewed every comment submission and identified 32 unique 
comments requiring the NRC's consideration and response. Comment 
summaries and the NRC's responses are presented in this section. At the 
end of each summary, the individual comments represented by the summary 
are identified in the form [XX-YY] where XX represents the Submission 
ID in Table III and YY represents the sequential comment within the 
submission.

Public Comments on Draft Regulatory Guides

Regulatory Guide 1.84, Revision 37 (DG-1295)
    No public comments were submitted regarding Regulatory Guide 1.84, 
Revision 37 (Draft Guide (DG)-1295), therefore no NRC response is 
needed.
Regulatory Guide 1.147, Revision 18 (DG-1296)
Code Case N-552-1
    Comment: The proposed conditions on N-552-1 were incorporated into 
the ASME BPV Code, Section XI, 2005 Addenda when Code Case N-552 was 
incorporated into the code. However, these conditions have never been 
incorporated into the Code Case itself. The proposed conditions are 
identical to those imposed on Code Case N-552 in Revision 16 of RG 
1.147. ASME does not object to these conditions. [ASME 5-2]
    NRC Response: The NRC agrees with this comment.
    No change was made to the final rule as a result of this comment.
Code Case N-576-2
    Comment: Because the NRC has adopted the 2008 Addenda with no 
conditions on IWA-4200, ASME recommends that the proposed

[[Page 2344]]

condition be revised to state ``. . . is to be performed in accordance 
with IWA-4200 of the code of record for the current ISI Program.'' 
[ASME 5-3]
    NRC Response: The NRC agrees, in part, with this comment. The NRC 
staff has adopted the 2008 Addenda with no conditions on IWA-4200. 
However, the staff does not agree that the proposed condition/note in 
Regulatory Guide 1.147 should be revised to state ``. . . is to be 
performed in accordance with IWA-4200 of the code of record for the 
current ISI program'', because there may be licensees whose code of 
record is prior to 2008 and such a condition is not necessary because 
licensees would be required to follow IWA-4200 in their code of record, 
if they were to adopt this Code Case. As a result, because use of the 
repair method described in this Code Case (N-576-2) requires the NRC's 
review and approval prior to implementation and licensees will be 
required to follow IWA-4200 in their code of record, the NRC modified 
the ``note'' on this Code Case to eliminate the portion of the ``note'' 
regarding reconciliation. The revised ``note'' now reads:
    ``Note: Steam generator tube repair methods require prior NRC 
approval through the Technical Specifications. This Code Case does not 
address certain aspects of this repair, e.g., the qualification of the 
inspection and plugging criteria necessary for staff approval of the 
repair method.''
Code Case N-638-6
    Comment: Condition 1 was incorporated into IWA-4673(a)(2) of the 
2013 Edition when N-638-6 was incorporated into the Code. This 
condition has also been incorporated into N-638-8, which has been 
published in the 2015 Code Case Book. Condition (2) was incorporated 
into IWA-4671(b)(1) of the 2013 Edition when N-638-6 was incorporated 
into the Code. Because there were no conditions imposed on the use of 
IWA-4673(a)(2) or IWA-4671(b)(1) in the draft rule, to incorporate by 
reference the 2013 Edition of the ASME BPV Code, Section XI, ASME 
recommends that both of the proposed conditions be removed and Code 
Case N-638-6 be moved to Table 1 of RG 1.147, Revision 18. [ASME 5-4]
    NRC Response: The NRC agrees, in part, with this comment. Regarding 
proposed Condition (1), the staff agrees that Condition (1) was 
incorporated into IWA-4673(a)(2) of the 2013 Edition of ASME BPV Code, 
Section XI, when ASME incorporated Code Case N-638-6 into the Section 
XI. Proposed Condition (1) was also addressed in Code Case N-638-8. 
However, Code Case N-638-6 does not address proposed Condition (1) and 
this version of the Code Case will be available for use by licensees 
who will not adopt the 2013 Edition of Section XI for several years. 
Therefore, the NRC determined that it is appropriate to include 
proposed Condition (1) in RG 1.147, Revision 18.
    Regarding proposed Condition (2), Paragraph 1(b)(1) of Code Case N-
638-6 contains changes from the previous version of the Code Case, 
which allows through-wall circumferential welds and includes additional 
requirements when performing repairs that utilize through-wall 
circumferential welds. At the time that this revision of the Code Case 
was approved by the ASME, the staff had concerns related to through-
wall repairs. Subsequently, the NRC resolved its concerns. Therefore, 
the NRC determined that proposed Condition (2) is unnecessary.
    The NRC has removed proposed Condition (2) on Code Case N-638-6 
from the final RG 1.147, Revision 18.
    No change was made to the final rule as a result of this comment.
Code Cases N-666 and N-666-1
    Comment: A new condition has been added to N-666, which is listed 
as a Superseded Code Case: A surface (magnetic particle or liquid 
penetrant) examination must be performed after installing the seal weld 
and weld overlay on Class 1 and 2 piping socket welds. The fabrication 
defects, if detected, must be dispositioned using the surface 
examination acceptance criteria of the Construction Code identified in 
the Repair/Replacement Plan.
    As stated in our comment on N-666-1, the phrase ``seal weld and'' 
should be removed from the first sentence. Also, the addition of a new 
condition to a Code Case that was previously unconditionally approved 
in the Reg. Guide, and is now superseded, seems inappropriate. Several 
plants would likely have this version of the Code Case in their Section 
XI ``tool box'' until the end of their current Inspection Interval, and 
would be apparently (but not obviously) bound by the new condition, 
upon issuance of the new revision to Regulatory Guide. The third 
paragraph under Section B. DISCUSSION, in the draft RG, includes the 
statement ``If a Code Case is implemented by a licensee and a later 
version of the Code Case is incorporated by reference into 10 CFR 
50.55a and listed in Tables 1 and 2 during the licensee's present 120-
month ISI program interval, that licensee may use either the later 
version or the previous version. An exception to this provision would 
be the inclusion of a limitation or condition on the use of the Code 
Case that is necessary, for example, to enhance safety.'' Perhaps this 
could be supplemented with another sentence such as, ``In this case, 
the condition will be entered for the superseded Code Case under Table 
5.'' [EPRI 2-4, Exelon 7-4]
    NRC Response: The NRC agrees with this comment. The condition shown 
in Table 5 of DG-1295 for Code Case N-666 was in error.
    The condition on Code Case N-666 in Table 5 from the final RG 
1.147, Revision 18 has been removed.
    No change was made to the final rule as a result of this comment.
    Comment: Condition 1--The construction code may not always require 
a surface examination (depending on the construction code) on socket 
welds. This condition is appropriate. However, the words ``and seal 
weld'' in the first sentence should be removed from the condition 
because it is inappropriate to require surface examination of non-
structural seal welds whose only function is to seal a leak. The ASME 
recommends revising this condition to remove the words ``and seal 
weld'' in the first sentence. Condition 2--This condition should be 
removed as 5(a)(1) already required a Visual VT-1 examination of 
completed weld overlays irrespective of the class of the joint. This 
condition is redundant and only causes confusion. ASME recommends 
removing this proposed condition. [EPRI 2-1, ASME 5-5]
    NRC Response: The NRC agrees with this comment. The function of the 
seal weld is to seal a leak so that sound weldment for the overlay can 
be applied. The code case requires a visual examination of the seal 
weld, remaining socket weld, and adjacent base material before the weld 
overlay can be applied, which the NRC has determined is the appropriate 
examination prior to the application of the weld overlay. Therefore, 
Condition 1 has been revised to remove ``and seal weld.'' Regarding 
Condition 2, the NRC agrees with the commenter. The code case requires 
a visual examination of the seal pass and the completed weld overlay 
and provides appropriate acceptance criteria. Therefore, the condition 
is redundant and unnecessary. Condition 2 has been removed from Code 
Case N-666 in Table 2 from the final RG 1.147, Revision 18.
    No change was made to the final rule as a result of this comment.

[[Page 2345]]

Code Case N-711
    Comment: ASME recommends that this Code Case N-711 be removed from 
RG 1.193, Table 2 and added to Table 2 of RG 1.147 with appropriate 
conditions to address NRC technical concerns with the use of this case. 
[ASME 5-10]
    NRC Response: The NRC disagrees with this comment. The NRC declines 
at this time to adopt the recommended changes to the regulatory guides. 
It would not be appropriate to include the Code Case in RG 1.147 
without first having sought public comment on the adoption of the Code 
Case. Nonetheless, the NRC has reviewed the information provided by 
ASME and will consider approval of the Code Case in future rulemaking 
activities.
    No change was made to the final rule as a result of this comment.
Code Case N-722-2
    Comment: ASME requests that the NRC identify any technical concerns 
with N-722-2 and list these concerns in R.G. 1.193, Table 2. [ASME 5-
11]
    NRC Response: The NRC disagrees with this comment. The NRC 
disagrees with the comment because the NRC does not provide comments in 
the Regulatory Guide 1.193 on ASME Code Cases, which the NRC mandates 
for use as augmented inservice inspection programs under Sec.  
50.55a(g)(6)(ii). Any conditions that the NRC finds necessary to 
require are included under the particular section of Sec.  
50.55a(g)(6)(ii)(D), (E) or (F), as applicable. This is to avoid 
confusion such that a stakeholder does not use versions of these ASME 
Code Cases in lieu of the mandated versions of the ASME Code Case in 
Sec.  50.55a(g)(6)(ii). However, in order to be responsive to the 
stakeholder comment, the NRC will provide the current concerns with the 
implementation of ASME Code Case N-722-2, as a response to this comment 
to be included in the Federal Register notice.
    The NRC currently finds ASME Code Case N-722-2 unacceptable as 
written due to the following main issues. First, the basis for the 
removal of the Parts Examined from N-722-1 was found to be in error. 
According to an ASME Code interpretation, XI-1-13-27, not all items 
removed in N-722-2 were covered by the inspection requirements of ASME 
Code Case N-770-1. The ASME Code Case N-722 will need to be revised 
with a new basis for the removal of Parts Examined to be considered for 
approval by the NRC. Second, Note 11 is not acceptable. The bases for 
this concern is the same basis as Sec.  50.55a(g)(6)(ii)(F)(2), which 
restricts the application of this material condition to exempt 
volumetric and visual examination requirements in N-770-1. The NRC is 
concerned that the wording of this exemption may allow insufficiently 
mitigated items to be exempt from currently required visual inspection 
requirements for components containing alloy 600/82/182 to maintain 
structural and leak-tight integrity. Once again though, it is not the 
intent of the NRC to include these items as conditions or limitations 
in the regulatory guide. The current wording to redirect the user to 
the applicable section of Sec.  50.55a(g)(6)(ii)(E) will remain, 
because versions of this ASME Code Case, as well as N-729 and N-770, 
are not alternatives to the Code requirements, but are mandated by 
Sec.  50.55a as augmented ISI requirements. For these reasons the NRC 
disagrees with the comment.
    No change was made to the final rule as a result of this comment.
Code Case N-749
    Comment: Public comment 5-6 raised two main points:
    1. The comment takes issue with the temperature, Tc, 
above which the staff suggests that EPFM techniques should be used. The 
formula for Tc, given in the staff's condition, differs from 
that proposed in Code Case N-749.
    2. The comment takes issue with the part of the staff's condition 
stating that ``Tc is the temperature above which elastic plastic 
fracture mechanics (EPFM) must be applied.'' Item 4 of the public 
comment suggests adopting a permissive rather than a perspective 
condition by replacing the word ``must'' with the word ``may'' in the 
preceding sentence. [ASME 5-6]
    NRC Response: The NRC disagrees with this comment. The staff's 
responses to these points are, as follows:
    Concerning point 1, the technical bases for the staff's proposed 
equation for Tc are well documented, as discussed 
previously, and are well supported by data for RPV steels both before 
and after neutron irradiation. This documentation appears in PVP 2015-
45307. Conversely, the Tc equation in the proposed Code Case 
relates only to the intersection of the ASME KIc curve with 
a fracture toughness (KIc) value of 220 MPa[radic]m, a value 
that does not correspond well to any known materials data and, 
moreover, does not account for the effects of irradiation 
embrittlement. The NRC staff's proposal for Tc is thus 
better supported by materials data than is the Code Case value.
    Concerning point 2, in order for a permissive condition to be 
acceptable (e.g., the use of ``may''), it would need to be demonstrated 
that application of LEFM approaches to flaw assessment on the upper 
shelf fracture behavior is always conservative relative to the more 
technically correct EPFM approach. This has not been demonstrated in 
either Code Case N-749 or in its supporting technical basis document. 
As one example, an approach to using LEFM on the upper shelf fracture 
behavior would be to continue to use the ASME KIc curve. At 
upper shelf temperatures, the KIc curve over-estimates the 
fracture toughness relative to the ductile fracture toughness (i.e., 
J0.1 or J-R), which is non-conservative.
    No change was made to the final rule as a result of this comment.
Code Case N-754
    Comment: The third condition proposed for this Code Case inversely 
paraphrases existing statements in the Code Case, causing confusion to 
the user as to what the condition actually adds to the existing 
requirements. Further, by paraphrasing the requirements, essential 
technical requirements, such as chrome content in the dilution zone, 
are omitted which we do not believe is the intent of the condition. The 
Federal Register states that the reason for this condition is that ``In 
this instance, the NRC felt the word ``may'' needed to be changed to 
``shall'' in the second sentence in paragraph 1.2(f)(2) as a condition 
for use of this Code Case.'' In the English language, when the term 
``may'' is followed by the word ``not'', the phrase means the same as 
``shall not.'' However, if this phrase is truly a concern for some, 
then the condition should be written exactly as the Code Case except 
change the one word ``may'' to ``shall.'' [EPRI 2-2, ASME 5-7]
    NRC Response: The NRC disagrees with this comment. Condition (3) 
addresses the following two statements in Paragraph 1.2(f)(2) of Code 
Case N-754 that reads: ``. . . The first layer of weld metal deposited 
may not be credited toward the required thickness, but the presence of 
this layer shall be considered in the design analysis requirements in 
2(b). Alternatively, a first diluted layer may be credited toward the 
required thickness, provided the layer and the associated dilution zone 
contain at least 24% Cr [chromium] . . .'' The first sentence in 
Paragraph 1.2(f)(2) could be interpreted so that the first weld layer 
could be credited toward the required thickness because the word ``may 
not'' does not absolutely prohibit such action. In addition, the first 
sentence in the quoted statements does not have restriction on

[[Page 2346]]

the chromium contents for crediting the first weld layer toward the 
required thickness.
    The second sentence in the above quote limits the chromium content 
of at least 24 percent; however, the second sentence began with the 
word ``Alternatively.'' The word ``Alternatively'' implies that the 
requirement in the second sentence is optional, i.e., a licensee may 
choose to satisfy either the first sentence or the second sentence, but 
the licensee does not need to satisfy both.
    For example, a licensee deposits a first weld layer that contains 
less than 24 percent chromium. The licensee could consider the first 
layer, as part of the required weld overlay thickness, based on the 
first sentence above because the first sentence does not identify a 
specific chromium content. Therefore, it does not restrict the 
consideration of the first layer for the required weld overlay 
thickness. The second sentence in the above quote does require the 
chromium content to be at least 24 percent. However, the licensee could 
interpret that the second sentence does not apply to this case because 
the second sentence is an alternate, optional requirement based on the 
word ``Alternatively.''
    The staff finds that Condition (3) does not omit the essential 
technical requirements such as the chrome content in the dilution zone. 
Condition (3) requires that if the first weld layer cannot achieve a 
chromium content of at least 24 percent, it cannot be considered as 
part of the weld overlay thickness. The staff recognizes that Condition 
(3) provides the same requirements as in Paragraph 1.2(f)(2). However, 
the purpose of Condition (3) is to clarify the requirements in 
Paragraph 1.2(f)(2).
    No change was made to the final rule as a result of this comment.
Code Case N-784
    Comment: This Code Case enables personnel to receive credit for 
experience hours for laboratory practice beyond the required number of 
hours of laboratory training. For Level II certification, the total 
experience hours may be reduced from 800 to 400 if the experience 
consists of a combination of 80 hours of field experience and 320 hours 
laboratory practice by scanning specimens containing flaws in materials 
representative of those in actual power plant components. The field 
experience will likely be in nuclear plants but there is no requirement 
for UT examiners to obtain their experience in a nuclear plant. While 
the experience credited would be on samples and mockups, those samples 
would be required to contain actual flaws whereas over many hours of 
field experience, fewer flaws may be encountered. Further, to ensure 
the effectiveness of the laboratory practice, the Level II experience 
time would be credited only after the individual passed an Appendix 
VIII, Supplement 2 performance demonstration for length and depth 
sizing. Since other performance demonstrations are required for 
certification for vessels, ferritic piping and bolting, for example, it 
is considered reasonable to only require the Supplement 2 performance 
demonstration as a threshold for crediting the laboratory practice 
hours. EPRI will provide reports (Nondestructive Evaluation: Fast-Track 
NDE Work Force Enhancement, Volume 1; 1019119 and Nondestructive 
Evaluation: Fast-Track NDE Work Force Enhancement, Volume 2, 1021150) 
to the USNRC to support this Code Case and address the impact of the 
reduced experience. This case does not reduce the training hours. [ASME 
5-12]
    NRC Response: The NRC disagrees with this comment. The ASME BPV 
Code replaces field experience with training hours without a defined 
technical basis. While the NRC is open to evidence related to a 
technical basis for the substitution of laboratory experience as a 
substitute for hours of work experience, the impact of the substitution 
of laboratory hours for field experience and nuclear power plant 
familiarization is unknown. The two documents cited in the comment 
require 1,050 hours of hands-on practice with hundreds of hours of 
additional classwork, not only 320 hours of laboratory training. If 
future work showed that 320 hours would be sufficient or the Code Case 
was modified to be in line with these documents, the NRC would consider 
allowing the use of the Code Case.
    No change was made to the final rule as a result of this comment.
Code Case N-789
    Comment: The NRC Condition [2] does not allow the user to apply the 
actual corrosion rate for the pressure pad design. This reflects the 
staff position that the factors of 2 and 4 do not provide reasonable 
assurance that actual corrosion rate is bounded. However, the 
compensatory measures of inservice monitoring and the short acceptance 
period of one operating cycle verify and provide assurance that both 
structural and leak integrity will be maintained during the temporary 
acceptance period. Condition (2) is contrary to several NRC SERs that 
have evaluated and approved the Code Case for application at dozens of 
domestic plants. Those SERs require that the reinforcing pad be 
designed to accommodate twice the actual measured corrosion rate or if 
unknown, then 4 times the maximum experienced in that or a similar 
system at the same plant for the same degradation mechanism. Corrosion 
rates are dependent upon many system variables--one primary factor 
being the amount and frequency of fluid flow. To impose the rate that 
may occur on a seldom-used dead-leg of a system to an area of active 
flow, where the actual corrosion rate has been measured is technically 
inappropriate. Since the monthly monitoring imposed by Condition (1) 
was initiated for the same reason that this condition was proposed--
namely, the potential for an unexpected corrosion rate--this condition 
should be removed. [EPRI 2-3, ASME 5-8]
    NRC Response: The NRC agrees with this comment. The NRC determined 
that the current language in the Code Case, which requires using a 
corrosion rate of either two times the actual measured corrosion rate 
in that location, or four times the estimated maximum corrosion rate 
for the system, is reasonable and provides a conservative estimate of 
the corrosion rate. This conservatively estimated corrosion rate, 
coupled with proposed Condition (1) that requires enhanced inservice 
monitoring, provides reasonable assurance that should corrosion rates 
be more aggressive than originally predicted, there will be sufficient 
time to initiate corrective actions prior to excessive leakage or loss 
of structural integrity. Therefore, the NRC has determined that 
proposed Condition (2) is not necessary.
    The NRC has removed proposed Condition (2) on Code Case N-789 from 
the final RG 1.147, Revision 18.
    No change was made to the final rule as a result of this comment.
    Comment: Paragraph 3.2(i) of Code Case N-789 has a typographic 
error where it states ``. . . piping designed to NC-2650, ND-3650. . . 
.'' NC-2650 should be NC-3650. Code Case N-789-2 corrected this 
statement to read ``. . . piping designed to NC-3650 or ND-3650. . . 
.'' The use of this Code Case N-789 should be conditioned to require 
using the corrected language for paragraph 3.2(i) in N-789-2. 
[Anonymous 3-1, Exelon 7-1]
    NRC Response: The NRC agrees with the commenter. Code Case N-789 
Paragraph 3.2(i) contains a typographical error. The code case 
references NC-2650 and the correct reference is NC-3650. NC-2650 does 
not exist in ASME Code Section III and

[[Page 2347]]

NC-3650 is the correct portion of the Code to use for the design of 
reinforcing pads. The NRC does not believe that this typographical 
error represents a safety concern. In order to prevent the delay of 
issuance of the final rule by including a new condition on the code 
case, the NRC will address this issue in a future rulemaking.
    No change was made to the final rule as a result of this comment.
Code Case N-795
    Comment: The commenters requested that one or both proposed 
conditions on the use of this Code Case in DG-1296 be removed: (1) 
Prohibition of use of nuclear heat to perform the leakage test; and (2) 
Hold time for noninsulated components must be 1 hour versus 15 minutes 
required by Code Case N-795. [Southern 4-1, ASME 5-9, and Exelon 7-2]
    NRC Response: The NRC agrees, in part, with this comment. As 
discussed in detail in the proposed rule in 81 FR 10780, dated March 2, 
2016, the historical prohibition of the use of nuclear heat for 
pressure testing is based on concerns about the quality of the VT-2 
examinations performed with the core critical, due to the high 
temperatures in containment, which limit stay times for inspectors, and 
also concerns about personnel safety. However, the commenters 
emphasized that Code Case N-795 is only intended for use in the case of 
limited scope repairs, such as the replacement of a main steam relief 
valve pilot valve (involving a single mechanical joint) when the relief 
valve is found to be leaking during startup. Code Case N-795 states 
that the alternative test pressure may not be used to satisfy the 
requirements of Table IWB-2500-1, Category B-P (the pressure test 
required once per cycle of the entire reactor coolant pressure 
boundary). Code Case N-795 does not place any restrictions on the size 
or scope of the repairs for which the alternative may be used, other 
than the alternative test pressure may not be used to satisfy pressure 
test requirements, following repair/replacement activities on the 
reactor vessel.
    However, upon review of the public comments, the staff has 
determined that the risk associated with performing the pressure test 
with nuclear heat at low power is comparable with the risk to the 
plant, when the test is performed without nuclear heat (with the core 
subcritical) during mid-cycle outages when decay heat must be managed. 
Performing the pressure test under shutdown conditions at full 
operating pressure without nuclear heat requires securing certain key 
pressure control, heat removal, and safety systems. Under such 
conditions, it is more difficult to control temperature and pressure, 
when there is significant decay heat production, such as after a mid-
cycle outage, which may reduce the margin available to prevent 
exceeding the plant pressure-temperature limits.
    The NRC considers it desirable that the scope of repairs be 
relatively small when the pressure test is conducted using nuclear 
heat, in order to minimize the personnel safety risk and to avoid 
rushed examinations. The staff considers it impractical to specify a 
particular number of welded or mechanical repairs that would constitute 
a ``limited scope.'' However, if the plant is still in a refueling 
outage and has already performed the ASME Section XI Category B-P 
pressure test of the entire RCPB, it is likely that subsequent repairs 
would be performed only on an emergent basis and would generally be of 
a limited scope. Additionally, the overall integrity of the RCPB will 
have been recently confirmed via the Category B-P test. For mid-cycle 
maintenance outages, the staff proposes to modify the condition to 
incorporate a limit on the outage duration of fourteen (14) days. This 
would tend to limit the scope of repairs, and also limit use of the 
Code Case to outages when decay heat was a significant problem. 
Therefore, the first condition on Code Case N-795 in Table 2 of DG-
1296, which currently reads:

    1. The use of nuclear heat to conduct the BWR Class 1 system 
leakage test is prohibited (i.e., the reactor must be in a non-
critical state).
    a. This condition also applies to pressure testing of reactor 
coolant pressure boundary components repaired or replaced in 
accordance with Section XI, IWA-4000.

is modified to read:

    1. The use of nuclear heat to conduct the BWR Class 1 system 
leakage test is prohibited (i.e., the reactor must be in a non-
critical state), except during refueling outages in which the ASME 
Section XI Category B-P pressure test has already been performed, or 
at the end of mid-cycle maintenance outages fourteen (14) days or 
less in duration.
    With respect to the comment on the second condition, the NRC 
disagrees with this comment. A one hour hold time is not 
unreasonable for non-insulated components. Inspectors do not need to 
be in containment during the hold time. Comment 5-9 (ASME) discussed 
the technical basis for Code Case N-795, which stated that pressure 
testing at 87 percent of full operating pressure would only result 
in a 7 percent reduction in flow, while the hold time is being 
increased by 50 percent from 10 minutes to 15 minutes. However, it 
is not possible to predict the entire range of scenarios or types of 
defects that could result in leakage. While some types of defects 
could result in immediate leakage, such as an improperly torqued 
bolted connection, other types of defects, such as weld defects or 
tight cracks could represent a more torturous path for leakage and 
may result in delayed leakage. Because the visual examination may be 
conducted with the core critical, stay times for examiners in 
containment may be limited; therefore, it is desirable that any 
leakage be readily detectable. The staff determined that, due to the 
uncertainty in the time required for leakage to occur, to an extent 
that it would be readily detectable by visual examination, it is 
appropriate to conservatively specify a longer hold time of 1 hour 
for non-insulated components. Therefore, no changes are made to 
Condition (2) requiring a 1-hour hold time for non-insulated 
components.

    No change was made to the final rule as a result of this comment.
Code Case N-799
    Comment: This is a Code Case to define the examination volume/area 
where older Section XI codes (up through 2010 Edition) do not recognize 
the defined configuration. The conditions proposed in the Code Case are 
not included in the proposed rule to accept the 2013 Edition of Section 
XI and the Code Case configuration is defined in the 2013 Code Edition. 
Commenters believe that this results in inconsistent requirements for 
plants using older Code versions versus newer Code versions. The 
examination conditions proposed for this Code Case use are not 
appropriate for a volume of interest Code Case. If the NRC considers 
the conditions appropriate, commenters believe that they should be 
included in a revision to 10 CFR 50.55a to assure consistent 
application, regardless of Code year and Addenda being applied. 
Specifically Conditions (3) and (5) should be removed from the Code 
Case. [Southern 4-2, Southern 4-3, and Exelon 7-3]
    NRC Response: The NRC agrees, in part, with this comment.
    Regarding the removal of proposed Condition (3) from N-799, the NRC 
disagrees with the comment. The NRC doesn't find that the examination 
of the inner \1/3\ of the component-to-component weld depicted in 
Figure 1 of Code Case N-799 provides reasonable assurance that the 
integrity of the component-to-component welds will be maintained 
throughout the operating life of the plant. Code Case N-799 was written 
to support new plant construction to provide examination requirements 
for a weld configuration, which did not exist in Section XI (i.e., 
component-to-component welds). Specifically, the examination 
requirements described in Code Case N-

[[Page 2348]]

799 would apply to the steam generator nozzle-to-reactor coolant pump 
casing (SG-to-RCP) weld in the AP1000 design and the reactor vessel 
nozzle-to-recirculation pump weld in the Advanced Boiling Water Reactor 
(ABWR). The following discussion will focus on the AP1000 design, but 
the staff's overall concern is also applicable to the reactor vessel-
to-reactor coolant pump connection for the ABWR design.
    The AP1000 design is unique in that a reactor coolant pump is 
welded directly to each of the two outlet nozzles on the steam 
generator channel head. This SG-to-RCP weld is a dissimilar metal (low 
alloy steel to cast austenitic stainless steel with Alloy 52/152 weld 
metal) circumferential butt weld with a double sided weld joint 
configuration, similar to that of a reactor vessel shell weld. Also, 
this unique component-to-component weld is part of the reactor coolant 
pressure boundary and is, therefore, subject to the examination 
requirements of ASME Section XI, Subsection IWB.
    ASME Section XI, IWB-2500 requires a full volume examination of all 
component welds, except those welds found in piping and those found in 
nozzles welded to piping. However, for the component-to-component welds 
in question, Code Case N-799 only requires a licensee to perform a 
volumetric examination of the inner \1/3\ of the weld and a surface 
examination of the outer diameter. The staff notes that the 
requirements of Code Case N-799 are identical to those in ASME Section 
XI, Table IWB-2500-1, Examination Category B-F for welds between vessel 
nozzles larger than NPS 4 and piping. As such, the staff does not 
believe that examination requirements proposed in Code Case N-799 are 
appropriate for the component-to-component welds because the service 
conditions of the aforementioned welds are significantly different from 
those that would be experienced by a traditional vessel nozzle-to-
piping/safe end butt weld. Specifically, in addition to the operating 
environment (RCS pressure, temperature, and exposure to coolant) and 
loads expected on a traditional nozzle-to-safe end weld, each SG-to-RCP 
weld will support the full weight of a reactor coolant pump with no 
other vertical or lateral supports. The SG-to-RCP welds will also be 
subject to pump rotational forces and vibration loads from both the 
steam generator and the reactor coolant pump during service. In the 
absence of operating experience for the weld in question or a bounding 
analysis, which demonstrates that a potential fabrication defect in the 
outer \2/3\ of the weld will not experience subcritical crack growth, 
the effects of these additional operating loads and stresses are 
indeterminate. Absent either of the above, the staff finds that it is 
inappropriate to limit the examination volume to the inner \1/3\ of the 
weld as typical of a piping weld at this time. When the examination 
volume that can be qualified by performance demonstration is less than 
100 percent of the weld volume, a licensee should include an ultrasonic 
examination to examine the qualified volume and perform a flaw 
evaluation of the largest hypothetical crack that could exist in the 
volume not qualified for ultrasonic examination. No change was made to 
the rule as a result of this comment.
    The NRC agrees that performing the examination in accordance with 
Section XI, Appendix VIII, Supplement 10, for detection and sizing 
would eliminate the need for the requirement to perform a flaw 
evaluation, based on the largest hypothetical flaw in the unqualified 
examination volume. However, the NRC determined a full volume 
examination of the entire weld and heat affected zone is required to 
provide reasonable assurance of structural integrity of the component-
to component welds addressed by Code Case N-799. The NRC also 
determined that requiring the examination procedures to be qualified in 
accordance with Section XI, Appendix VIII, Supplement 10, would 
eliminate the need for several of the other conditions that were 
proposed for N-799. Therefore, the final regulatory guide was modified 
to specify only four conditions for Code Case N-799, as follows:

    (i) Ultrasonic examination procedures, equipment, and personnel 
shall be qualified by performance demonstration in accordance with 
Section XI, Appendix VIII, Supplement 10. When applying the 
examination requirements of Figure IWB-2500-8, the examination 
volume shall be extended to include 100 percent of the weld.
    (ii) Examination requirements of Section XI, Mandatory Appendix 
I, paragraph I-3200(c) must be applied.
    (iii) Ultrasonic depth and sizing qualifications for cast 
austenitic stainless steel components must follow Appendix VIII, 
Supplement 10, using representative cast austenitic stainless steel 
mockups containing representative cracks and be independent of other 
Supplement 10 qualifications.
    (iv) Cracks detected and not depth sized to Appendix VIII type 
performance-based procedures, equipment, and personnel 
qualifications shall be repaired or removed.

    The NRC agrees with the examination requirement regarding the 
consistency between the Code Case and the codes, where the Code Case 
that has been incorporated should be consistent. The NRC disagrees with 
the statement that the proposed conditions are not appropriate for a 
volume of interest Code Case. The NRC is planning to include this topic 
in a future rulemaking.
Code Case N-806
    Comment: ASME stated that it has taken action to address some of 
these concerns and has published Code Case N-806-1, providing 
additional requirements for determining wall thickness loss rates. The 
ASME recommends that the NRC consider developing conditions on the use 
of this case that would enable the endorsement of the case in Table 2 
of RG 1.147. [ASME 5-13]
    NRC Response: The NRC disagrees with this comment. The NRC 
recognizes that ASME has addressed the NRC's concerns regarding the 
derivation of the corrosion rate in predicting metal loss in piping and 
has incorporated the corrosion rate derivation in the published Code 
Case N-806-1. However, the current rulemaking is for Code Case N-806, 
which does not contain sufficient information regarding the corrosion 
rate. The ASME suggested that the NRC develop conditions on the use of 
the Code Case such that the NRC could approve the Code Case for RG 
1.147. The NRC has determined that approval of Code Case N-806 with 
conditions would require too many conditions to address several open 
issues regarding the relationship to the derivation of the corrosion 
rate, which still need to be resolved. Therefore, the NRC cannot 
approve Code Case N-806 in this rulemaking.
    No change was made to the final rule as a result of this comment.
Code Case N-813
    Comment: This Code Case should be removed from Table 2 of 
Regulatory Guide 1.193 and added to Table 1 of Regulatory Guide 1.147 
because of the following reasons.

    1. The requirements of Code Case N-813 are identical to changes 
made in the 2013 Edition of Section XI, which are being considered 
under a separate draft 10 CFR 50.55a rule. The NRC has not proposed 
any conditions on these requirements in the 2013 Edition. It is 
inappropriate for the NRC to impose conditions on the same 
requirements in Case N-813 as the requirements in the 2013 Edition.
    2. This Case permits acceptance of subsurface flaws detected 
during preservice examination using the same criteria applicable to 
flaws detected during inservice examination. There is no greater 
likelihood of subsurface flaws detected during preservice 
examination to grow unacceptably than there is for the same flaws to 
grow during inservice examination. Operating experience has

[[Page 2349]]

shown that the propensity for failure is increased by repairing such 
flaws, whereas leaving them in place has never been shown to be a 
precursor to failure. Without weld repair, there is no mechanism 
expected to produce unacceptable flaw growth, whereas repair welding 
itself has been repeatedly shown to cause flaws to grow to the point 
of failure. The provisions of this Case, and the identical 
provisions in the 2013 Edition, improve safety.
    3. The technical basis for this Code Case and accompanying Code 
revision states that the action is being sought to prevent the 
unnecessary excavation and weld repair of subsurface indications, 
which can be analytically shown to be benign over the expected 
service lifetime of a component. Based on operating experience, it 
is known that weld repairs and their associated stress fields often 
serve as points of initiation for inservice degradation mechanisms 
(e.g., intergranular stress corrosion cracking, primary water stress 
corrosion cracking, etc.). Hence, it is in the best interest of the 
long term safe operation of components being placed into service to 
eliminate the need for weld repairs where they are not necessary to 
correct fabrication problems, which will not challenge the 
operability of the component over its service lifetime. This can be 
achieved by permitting licensees to effectively utilize the flaw 
evaluation rules of IWB-3600 and IWC-3600, which are already 
accepted for the analysis of indications due to inservice 
degradation.
    4. It is important to note that any preservice flaw that has 
been evaluated as acceptable is required to receive successive 
examinations under IWB-2420(b) or IWC-2420(c) so if the flaw does 
grow, it will be detected during these examinations. [ASME 5-14]

    NRC Response: The NRC disagrees with this comment, in part. The NRC 
has recognized that the provisions in Code Case N-813 are identical to 
changes made in the 2013 Edition of the ASME BPV Code, Section XI. The 
NRC addressed the contents of the 2013 Edition of the ASME BPV Code, 
including the Code provisions identical to those allowed in Code Case 
N-813, in a separate rulemaking.
    The NRC recognizes that operating experience has shown that 
repairing a weld that contains fabrication defects may cause the defect 
to grow in the future. On the other hand, permitting a weld that 
contains a known unacceptable fabrication defect prior to deployment is 
not appropriate and is contrary to the fundamental engineering 
principle of a good design. The fundamental engineering design is that 
a component should not contain defects before placing it into service. 
The staff has accepted the provision of ASME BPV Code, Section III that 
permits acceptable flaws (i.e., small insignificant flaws) in a weld to 
exist before deployment. The staff's objection to Code Case N-813 is 
that the code case permits the existence of unacceptable flaws, which 
do not meet the ASME Code preservice acceptance criteria, in welds 
before their deployment. The code case allows these unacceptable flaws 
to be accepted by analytical evaluation. The code case places no limits 
on such flaws (i.e., a weld could have more than one unacceptable flaw 
or numerous welds within a piping run could have flaws that did not 
meet the preservice acceptance criteria), whereas the original fleet of 
nuclear plants had no unacceptable preservice flaws. The staff 
concludes that it cannot approve Code Case N-813 in this rulemaking. 
The NRC will continue to evaluate operating experience relative to this 
type of flaw to further inform decisions on possible approval of this 
code case in future rulemakings.
    No change was made to the final rule as a result of this comment.
Code Case N-818
    Comment: Code Case N-818 should be removed from Regulatory Guide 
1.193 and be allowed for use, as the reasons given in Regulatory Guide 
1.193 to disallow Code Case N-818 have the following issues: (a) The 
fact that the examination will be difficult should not be a reason to 
prohibit it as Mandatory Appendix I requires that the technique(s) to 
be applied for the volumetric procedure be demonstrated on specimens 
simulating geometric, material and surface conditions to be encountered 
during implementation. (b) The discussion that ultrasound may have 
difficulties discerning between planar and volumetric flaws is not 
relevant. There is no requirement in the Code Case to characterize the 
flaw by type (i.e., planar or volumetric). (c) The suggestion that its 
application should be limited to ferritic weldments defeats the purpose 
of Code Case N-818. [EPRI 2-5, Southern 4-4]
    NRC Response: The NRC disagrees with this comment, in part. At 
present, the NRC has not received any supporting documents from the 
industry to address the NRC's concern regarding this Code Case, such as 
a demonstration of the adequacy of a full volume ultrasonic examination 
for fabrication flaws in austenitic welds. Therefore, the wording of 
the reasons given in RG 1.193 should not refer to the inspection being 
difficult for austenitic materials and dissimilar metal welds, but 
should instead refer to there not being an established technical basis 
for the use of ultrasound to find fabrication flaws in these materials. 
Additionally, the discussion of planar vs. volumetric flaws will be 
removed from RG 1.193, as the Code Case does not require the examiner 
to discriminate between these types of flaws. The revised wording for 
RG 1.193 is:

    The NRC has been conducting research at Pacific Northwest 
National Laboratory on the examination of austenitic and ferritic 
welds. The work has shown that performing a full volume ultrasonic 
examination for fabrication flaws is significantly different from an 
inservice examination. For example, examination from two directions 
is necessary to detect certain circumferentially oriented 
fabrication flaws such as lack of fusion. The work has also shown 
that the second leg of a V-path can be applied to examine ferritic 
materials on a limited basis but to date the technical basis has not 
been established to show that these techniques will be effective on 
austenitic materials and dissimilar metal welds. Another finding is 
that surface conditions are critical with respect to detecting and 
characterizing fabrication flaws. In summary, the NRC finds that an 
analytical approach for the acceptance of certain fabrication flaws 
could be acceptable if appropriately justified and the scope limited 
to ferritic materials. The NRC finds that significant research will 
be required to demonstrate that full-volume ultrasonic examination 
for fabrication flaws is acceptable for austenitic and dissimilar 
metal welds.

Regulatory Guide 1.192, Revision 2 (DG-1297)
Code Case OMN-20
    Comment: Allow the use of Code Case OMN-20 for those plants that 
implement ASME OM Code 2015 Edition and earlier editions and addenda. 
[Gowin 6-1]
    NRC Response: The NRC agrees, in part, with this comment. Code Case 
OMN-20 cannot be implemented with the 2015 Edition of the ASME OM Code 
because the 2015 Edition has not been incorporated by reference into 
Sec.  50.55a. Code Case OMN-20 is currently applicable to the 2009 
Edition through the OMa-2011 Addenda and all earlier editions and 
addenda. Licensees who adopt the 2012 Edition of the ASME OM Code would 
not be able to use Code Case OMN-20, without submitting a relief 
request to the NRC for approval. For this reason, the NRC partially 
agrees with the comment. The NRC believes that Code Case OMN-20 should 
be allowed to be implemented with the 2012 Edition and earlier editions 
and addenda of the ASME OM Code. The RG 1.192 was updated to add a 
condition stating that Code Case OMN-20 is applicable to the editions 
and addenda of the ASME OM Code listed in Sec.  50.55a(a)(1)(iv).
    No change was made to the final rule as a result of this comment.

[[Page 2350]]

Public Comments on the Proposed Rule

    Comment: The ASME Code is updated every year. Preparations are 
underway to publish the 2017 edition. NRC is working on 2010 Edition. 
It appears that NRC is not in compliance with National Technology 
Transfer and Advancement Act of 1995 (NTTAA) by passive non-compliance. 
Since NRC has many participants in the Code process, they should be 
prepared to act as soon as final standards votes are counted. [Donavin 
1-1]
    NRC Response: The NRC disagrees with this comment. The NRC 
appreciates the ASME's efforts to consider the NRC's concerns as 
addressed in conditions to Sec.  50.55a. The NRC agrees that delays in 
approving new ASME Code editions and Code Cases can be 
counterproductive with respect to implementation of improvements in 
ASME Code requirements. The NRC continues to assess ways to improve the 
rulemaking process to find schedule efficiencies.
    No change was made to the final rule as a result of this comment.
    Comment: Many of the conditions are historical and are the result 
of a single reviewer's opinion. An example is the rules for the 1994 
edition where I watched an NRC reviewer living in Washington, DC 
telling a PhD from Tokyo, Japan, that his seismic analysis defending 
the edition was non conservative. If there are legitimate questions, 
these should be separated from the ``not sufficiently conservative'' or 
``insufficient information'' justifications. The Commission has set a 
precedent in CVR for SECY-15-0106. ASME has endeavored to address 
conditions with docketed letters and Code actions. [Donavin 1-2]
    NRC Response: The NRC disagrees with this comment. Although a 
single reviewer may state a contrary position, NRC reviews all Code 
Cases and comments with appropriate staff and management. Code Cases 
that the NRC finds to be conditionally acceptable are also listed in 
RGs 1.84, 1.147, and 1.192, which are the subject of this rulemaking, 
together with the conditions that must be used if the Code Case is 
applied. The NRC determined that this rule complies with the NTTAA and 
OMB Circular A-119, despite these conditions. If the NRC did not 
conditionally accept ASME Code Cases, it would disapprove these Code 
Cases entirely.
    No change was made to the final rule as a result of this comment.
    Comment: ASME believes that it is not clear whether the word 
``superseded'' applies to those Code Cases that are superseded by ASME 
or those Code Cases that are listed as superseded in Table 5 of 
Regulatory Guide 1.147.
    ASME recommends revising the second sentence of this paragraph to 
clarify that ``The older or superseded version of the Code Case, if 
listed in Table 5, cannot be applied by the licensee or applicant for 
the first time.'' [ASME 5-1]
    NRC Response: The NRC agrees with this comment. The proposed 
additional text will add clarity to the information presented in Table 
5. The final RG 1.147 in the introductory paragraph to Table 5, has 
been revised to include the statement, ``The older or superseded 
version of the Code Case, if listed in Table 5, cannot be applied by 
the licensee or applicant for the first time.'' at the end of the 
explanatory text above Table 5.
    No change was made to the final rule as a result of this comment.
    Comment: The Code Case [N-711] would permit each licensee to 
independently determine when achievement of a coverage requirement is 
impractical, and when Code-required coverage is satisfied. As a result, 
application of the Code Case for similar configurations at different 
plants could result in potentially significant quantitative variations. 
Furthermore, application of the Code Case is inconsistent with NRC's 
responsibility for determining whether examinations are impractical, 
and eliminates the NRC's ability to take exception to a licensee's 
proposed action and impose additional measures where warranted in 
accordance with 10 CFR 50.55a(g)(6)(i).
    ASME recommends that this case be removed from RG 1.193, Table 2 
and added to Table 2 of RG 1.147 with appropriate conditions to address 
NRC technical concerns with the use of this case. [ASME 5-10]
    NRC Response: The NRC agrees with this comment. However, this is a 
new proposal and cannot be included in this rulemaking because it was 
not provided for public comment. Rather than include the action in this 
rulemaking, the NRC intends to include it within the scope of the 
rulemaking that will incorporate by reference the 2015 edition of the 
ASME BPV Code.
    No change was made to the final rule as a result of this comment.
    Comment: In Section IV, ``Section-by-Section Analysis'' of the 
Proposed Rule dated March 2, 2016 (Federal Register Vol. 81, No. 41), 
ASME believes that it is not clear whether the word ``superseded'' 
applies to those Code Cases that are superseded by ASME or those Code 
Cases that are listed as superseded in Table 5 of Regulatory Guide 
1.147 and in Table 5 of Regulatory Guide 1.84. [ASME 5-1 and ASME 5-15]
    ASME provides the following recommendations:
    i. ASME recommends that the NRC clarify the above concern in the 
final rule.
    ii. ASME recommends that the NRC review requirements for superseded 
ASME Section III and OM Code Cases in RG 1.84 and RG 1.192 for similar 
clarification.
    NRC Response: The NRC agrees with this comment as noted in the 
response to Comment 5-1. In addition to that clarifying text being 
added in the introduction to Table 5 in RG 1.147, it will also be added 
to the introduction of Table 5 in RG 1.84. The RG 1.192 does not 
contain a table of superseded Code Cases, therefore, no change will be 
made to the RG 1.192.
    No change was made to the final rule as a result of this comment.

V. Section-by-Section Analysis

    The following paragraphs in Sec.  50.55a, which list the three RGs 
that are being incorporated by reference, are revised as follows:
    Paragraphs (a)(3)(i): The reference to ``NRC Regulatory Guide 1.84, 
Revision 36,'' is amended to remove ``Revision 36'' and add in its 
place ``Revision 37.''
    Paragraphs (a)(3)(ii): The reference to ``NRC Regulatory Guide 
1.147, Revision 17,'' is amended to remove ``Revision 17'' and add in 
its place ``Revision 18.''
    Paragraphs (a)(3)(iii): The reference to ``NRC Regulatory Guide 
1.192, Revision 1,'' is amended to remove ``Revision 1'' and add in its 
place ``Revision 2.''

Overall Considerations on the Use of ASME Code Cases

    This rulemaking amends Sec.  50.55a to incorporate by reference RG 
1.84, Revision 37, which supersedes Revision 36; RG 1.147, Revision 18, 
which supersedes Revision 17; and RG 1.192, Revision 2, which 
supersedes Revision 1. The following general guidance applies to the 
use of the ASME Code Cases approved in the latest versions of the RGs 
that are incorporated by reference into Sec.  50.55a as part of this 
rulemaking.
    The approval of a Code Case in the NRC RGs constitutes acceptance 
of its technical position for applications that are not precluded by 
regulatory or other requirements or by the recommendations in these or 
other RGs. The applicant and/or licensee are responsible for ensuring 
that use of the Code Case does not conflict with regulatory 
requirements or licensee

[[Page 2351]]

commitments. The Code Cases listed in the RGs are acceptable for use 
within the limits specified in the Code Cases. If the RG states an NRC 
condition on the use of a Code Case, then the NRC condition supplements 
the Code Case, and does not supersede any condition(s) specified in the 
Code Case, unless otherwise stated in the NRC condition.
    The ASME Code Cases may be revised for many reasons (e.g., to 
incorporate operational examination and testing experience and to 
update material requirements based on research results). On occasion, 
an inaccuracy in an equation is discovered or an examination, as 
practiced, is found not to be adequate to detect a newly discovered 
degradation mechanism. Hence, when an applicant or a licensee initially 
implements a Code Case, Sec.  50.55a requires that the applicant or the 
licensee implement the most recent version of that Code Case, as listed 
in the RGs incorporated by reference. Code Cases superseded by revision 
are no longer acceptable for new applications, unless otherwise 
indicated.
    Section III of the ASME BPV Code applies only to new construction 
(i.e., the edition and addenda to be used in the construction of a 
plant are selected based on the date of the construction permit and are 
not changed thereafter, except voluntarily by the applicant or the 
licensee). Hence, if a Section III Code Case is implemented by an 
applicant or a licensee and a later version of the Code Case is 
incorporated by reference into Sec.  50.55a and listed in the RGs, the 
applicant or the licensee may use either version of the Code Case 
(subject, however, to whatever change requirements apply to its 
licensing basis (e.g., 10 CFR 50.59)).
    A licensee's ISI and IST programs must be updated every 10 years to 
the latest edition and addenda of Section XI and the OM Code, 
respectively, that were incorporated by reference into Sec.  50.55a and 
in effect 12 months prior to the start of the next inspection and 
testing interval. Licensees who were using a Code Case prior to the 
effective date of its revision may continue to use the previous version 
for the remainder of the 120-month ISI or IST interval. This relieves 
licensees of the burden of having to update their ISI or IST program 
each time a Code Case is revised by the ASME and approved for use by 
the NRC. Code Cases apply to specific editions and addenda, and Code 
Cases may be revised if they are no longer accurate or adequate, so 
licensees choosing to continue using a Code Case during the subsequent 
ISI or IST interval must implement the latest version incorporated by 
reference into Sec.  50.55a and listed in the RGs.
    The ASME may annul Code Cases that are no longer required, are 
determined to be inaccurate or inadequate, or have been incorporated 
into the BPV or OM Codes. If an applicant or a licensee applied a Code 
Case before it was listed as annulled, the applicant or the licensee 
may continue to use the Code Case until the applicant or the licensee 
updates its construction Code of Record (in the case of an applicant, 
updates its application) or until the licensee's 120-month ISI or IST 
update interval expires, after which the continued use of the Code Case 
is prohibited, unless NRC authorization is given under Sec.  50.55a(z). 
If a Code Case is incorporated by reference into Sec.  50.55a and later 
annulled by the ASME because experience has shown that the design 
analysis, construction method, examination method, or testing method is 
inadequate, the NRC will amend Sec.  50.55a and the relevant RG to 
remove the approval of the annulled Code Case. Applicants and licensees 
should not begin to implement such annulled Code Cases in advance of 
the rulemaking.
    A Code Case may be revised, for example, to incorporate user 
experience. The older or superseded version of the Code Case cannot be 
applied by the licensee or applicant for the first time.
    If an applicant or a licensee applied a Code Case before it was 
listed as superseded, the applicant or the licensee may continue to use 
the Code Case until the applicant or the licensee updates its 
Construction Code of Record (in the case of an applicant, updates its 
application) or until the licensee's 120-month ISI or IST update 
interval expires, after which the continued use of the Code Case is 
prohibited, unless NRC authorization is given under Sec.  50.55a(z). If 
a Code Case is incorporated by reference into Sec.  50.55a and later a 
revised version is issued by the ASME because experience has shown that 
the design analysis, construction method, examination method, or 
testing method is inadequate; the NRC will amend Sec.  50.55a and the 
relevant RG to remove the approval of the superseded Code Case. 
Applicants and licensees should not begin to implement such superseded 
Code Cases in advance of the rulemaking.

VI. Regulatory Flexibility Certification

    Under the Regulatory Flexibility Act, 5 U.S.C. 605(b), the NRC 
certifies that this rule does not have a significant economic impact on 
a substantial number of small entities. This final rule affects only 
the licensing and operation of nuclear power plants. The companies that 
own these plants do not fall within the scope of the definition of 
``small entities'' set forth in the Regulatory Flexibility Act or the 
size standards established by the NRC (Sec.  2.810).

VII. Regulatory Analysis

    The NRC has prepared a final regulatory analysis on this 
regulation. The analysis examines the costs and benefits of the 
alternatives considered by the NRC. The total estimated net benefit of 
this rule is $4.94 million (7% discount rate) and $5.68 million (3% 
discount rate). The regulatory analysis is available as indicated in 
the ``Availability of Documents'' section of this document.

VIII. Backfitting and Issue Finality

    The provisions in this rule allow licensees and applicants to 
voluntarily apply NRC-approved Code Cases, sometimes with NRC-specified 
conditions. The approved Code Cases are listed in the three RGs that 
are incorporated by reference into Sec.  50.55a.
    An applicant's or a licensee's voluntary application of an approved 
Code Case does not constitute backfitting, inasmuch as there is no 
imposition of a new requirement or new position. Similarly, voluntary 
application of an approved Code Case by a 10 CFR part 52 applicant or 
licensee does not represent NRC imposition of a requirement or action 
that is inconsistent with any issue finality provision in 10 CFR part 
52. The NRC finds that this rule does not involve any provisions 
requiring the preparation of a backfit analysis or documentation 
demonstrating that one or more of the issue finality criteria in 10 CFR 
part 52 are met.

IX. Plain Writing

    The Plain Writing Act of 2010 (Pub. L. 111-274) requires Federal 
agencies to write documents in a clear, concise, and well-organized 
manner. The NRC has written this document to be consistent with the 
Plain Writing Act as well as the Presidential Memorandum, ``Plain 
Language in Government Writing,'' published June 10, 1998 (63 FR 
31883).

X. Environmental Assessment and Final Finding of No Significant 
Environmental Impact

    The Commission has determined under the National Environmental 
Policy Act of 1969, as amended, and the Commission's regulations in 
subpart A of 10 CFR part 51, that this rule, if adopted, would not be a 
major Federal action significantly affecting the quality of the human 
environment; therefore, an

[[Page 2352]]

environmental impact statement is not required.
    The determination of this environmental assessment is that there 
will be no significant effect on the quality of the human environment 
from this action. As alternatives to the ASME Code, NRC-approved Code 
Cases provide an equivalent level of safety. Therefore, the probability 
or consequences of accidents is not changed. There are also no 
significant, non-radiological impacts associated with this action 
because no changes would be made affecting non-radiological plant 
effluents and because no changes would be made in activities that would 
adversely affect the environment. The determination of this 
environmental assessment is that there will be no significant offsite 
impact to the public from this action.

XI. Paperwork Reduction Act

    This final rule contains new or amended collections of information 
subject to the Paperwork Reduction Act of 1995 (44 U.S.C. 3501 et 
seq.). The collection of information was approved by the Office of 
Management and Budget (approval number 3150-0011).
    The burden to the public for these information collections is 
estimated to average a reduction of 380 hours per response, including 
the time for reviewing instructions, searching existing data sources, 
gathering and maintaining the data needed, and completing and reviewing 
the information collection.
    The information collection is being conducted to document the plans 
for and the results of inservice inspection and inservice testing 
programs. The records are generally historical in nature and provide 
data on which future activities can be based. The practical utility of 
the information collection for the NRC is that appropriate records are 
available for auditing by NRC personnel to determine if ASME BPV and OM 
Code provisions for construction, inservice inspection, repairs, and 
inservice testing are being properly implemented in accordance with 
Sec.  50.55a of the NRC regulations, or whether specific enforcement 
actions are necessary. Responses to this collection of information are 
generally mandatory under Sec.  50.55a.
    You may submit comments on any aspect of the information 
collection(s), including suggestions for reducing the burden, by the 
following methods:
     Federal Rulemaking Website: Go to http://www.regulations.gov and search for Docket ID NRC-2012-0059.
     Mail comments to: Information Services Branch, Office of 
the Chief Information Officer, Mail Stop: T-2 F43, U.S. Nuclear 
Regulatory Commission, Washington, DC 20555-0001 or to Aaron Szabo, 
Desk Officer, Office of Information and Regulatory Affairs (3150-0011), 
NEOB-10202, Office of Management and Budget, Washington, DC 20503; 
telephone 202-395-3621, email: [email protected].

Public Protection Notification

    The NRC may not conduct or sponsor, and a person is not required to 
respond to, a request for information or an information collection 
requirement, unless the requesting document displays a currently valid 
OMB control number.

XII. Congressional Review Act

    This final rule is a rule as defined in the Congressional Review 
Act (5 U.S.C. 801-808). However, the Office of Management and Budget 
has not found it to be a major rule, as defined in the Congressional 
Review Act.

XIII. Voluntary Consensus Standards

    The National Technology Transfer and Advancement Act of 1995, 
Public Law 104-113, requires that Federal agencies use technical 
standards that are developed or adopted by voluntary consensus 
standards bodies, unless using such a standard is inconsistent with 
applicable law or is otherwise impractical. In this rule, the NRC is 
continuing to use ASME BPV and OM Code Cases, which are ASME-approved 
alternatives to compliance with various provisions of the ASME BPV and 
OM Codes. The NRC's approval of the ASME Code Cases is accomplished by 
amending the NRC's regulations to incorporate by reference the latest 
revisions of the following, which are the subject of this rulemaking, 
into Sec.  50.55a: RG 1.84, Revision 37; RG 1.147, Revision 18; and RG 
1.192, Revision 2. These RGs list the ASME Code Cases that the NRC has 
approved for use. The ASME Code Cases are national consensus standards, 
as defined in the National Technology Transfer and Advancement Act of 
1995 and OMB Circular A-119. The ASME Code Cases constitute voluntary 
consensus standards, in which all interested parties (including the NRC 
and licensees of nuclear power plants) participate.

XIV. Incorporation by Reference--Reasonable Availability to Interested 
Parties

    The NRC is incorporating by reference three NRC Regulatory Guides 
that list new and revised ASME Code Cases, which the NRC has approved 
as alternatives to certain provisions of NRC-required Editions and 
Addenda of the ASME BPV Code and the ASME OM Code.
    The NRC is required by law to obtain approval for incorporation by 
reference from the Office of the Federal Register (OFR). The OFR's 
requirements for incorporation by reference are set forth in 1 CFR part 
51. On November 7, 2014, the OFR adopted changes to its regulations 
governing incorporation by reference (79 FR 66267). The OFR regulations 
require an agency to include, in a proposed rule, a discussion of the 
ways that the materials the agency proposes to incorporate by reference 
are reasonably available to interested parties or how it worked to make 
those materials reasonably available to interested parties. The 
discussion in this section complies with the requirement for final 
rules, as set forth in 1 CFR 51.5(b).
    The NRC considers ``interested parties'' to include all potential 
NRC stakeholders, not only the individuals and entities regulated or 
otherwise subject to the NRC's regulatory oversight. These NRC 
stakeholders are not a homogenous group, so the considerations for 
determining ``reasonable availability'' vary by class of interested 
parties. The NRC identifies six classes of interested parties with 
regard to the material to be incorporated by reference in an NRC rule:
     Individuals and small entities regulated or otherwise 
subject to the NRC's regulatory oversight. This class includes 
applicants and potential applicants for licenses and other NRC 
regulatory approvals, and who are subject to the material to be 
incorporated by reference. In this context, ``small entities'' has the 
same meaning as set out in Sec.  2.810.
     Large entities otherwise subject to the NRC's regulatory 
oversight. This class includes applicants and potential applicants for 
licenses and other NRC regulatory approvals, and who are subject to the 
material to be incorporated by reference. In this context, a ``large 
entity'' is one which does not qualify as a ``small entity'' under 
Sec.  2.810.
     Non-governmental organizations with institutional 
interests in the matters regulated by the NRC.
     Other Federal agencies, states, local governmental bodies 
(within the meaning of Sec.  2.315(c)).
     Federally-recognized and State-recognized \7\ Indian 
tribes.
---------------------------------------------------------------------------

    \7\ State-recognized Indian tribes are not within the scope of 
10 CFR 2.315(c). However, for purposes of the NRC's compliance with 
1 CFR 51.5, ``interested parties'' includes a broad set of 
stakeholders including State-recognized Indian tribes.

---------------------------------------------------------------------------

[[Page 2353]]

     Members of the general public (i.e., individual, 
unaffiliated members of the public who are not regulated or otherwise 
subject to the NRC's regulatory oversight) and who need access to the 
materials that the NRC proposes to incorporate by reference in order to 
participate in the rulemaking.
    The three regulatory guides being incorporated by reference in this 
rule are available without cost and can be read online, downloaded, or 
viewed, by appointment, at the NRC Technical Library, which is located 
at Two White Flint North, 11545 Rockville Pike, Rockville, Maryland 
20852; telephone: 301-415-7000; e-mail: [email protected]; url: 
www.nrc.gov/reading-rm/doc-collections/.
    Because access to the three regulatory guides are available in 
various forms and at no cost, the NRC determines that the three 
regulatory guides, RG 1.84, Revision 37; RG 1.147, Revision 18; and RG 
1.192, Revision 2, once approved by the OFR for incorporation by 
reference, are reasonably available to all interested parties.

XV. 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.

                 Table IV--Rulemaking Related Documents
------------------------------------------------------------------------
                                                 ADAMS accession No./
               Document title                 Federal Register citation/
                                                       web link
------------------------------------------------------------------------
Proposed Rule Documents:
    Proposed Rule--Federal Register notice,  81 FR 10780.
     March 2, 2016.
    Draft Regulatory Analysis..............  ML15041A816.
    Draft RG 1.84, Revision 37 (DG-1295)...  ML15027A002.
    Draft RG 1.147, Revision 18 (DG-1296)..  ML15027A202.
    Draft RG 1.192, Revision 2 (DG-1297)...  ML15027A330.
Final Rule Documents:
    Regulatory Analysis....................  ML16285A013.
    RG 1.84, Revision 37...................  ML16321A335.
    RG 1.147, Revision 18..................  ML16321A336.
    RG 1.192, Revision 2...................  ML16321A337.
Related Documents:
    Draft RG 1.193, ``ASME Code Cases Not    ML15028A003.
     Approved for Use,'' Revision 5. (DG-
     1298).
    Federal Register notice--                82 FR 32934.
     ``Incorporation by Reference of
     American Society of Mechanical
     Engineers Codes and Code Cases,'' July
     18, 2017.
    Federal Register notice--                80 FR 56820.
     ``Incorporation by Reference of
     American Society of Mechanical
     Engineers Codes and Code Cases,''
     September 18, 2015.
    Federal Register notice--                68 FR 40469.
     ``Incorporation by Reference of ASME
     BPV and OM Code Cases,'' July 8, 2003.
    Federal Register notice--``Fracture      60 FR 65456.
     Toughness Requirements for Light Water
     Reactor Pressure Vessels,'' December
     19, 1995.
    Information Notice No. 98-13, ``Post-    ML031050237.
     Refueling Outage Reactor Pressure
     Vessel Leakage Testing Before Core
     Criticality,'' April 20, 1998.
    Inspection Report 50-254/97-27.........  ML15216A276.
    Letter from James M. Taylor, Executive   ML14273A002.
     Director for Operations, NRC, to
     Messrs. Nicholas S. Reynolds and
     Daniel F. Stenger, Nuclear Utility
     Backfitting and Reform Group, February
     2, 1990.
    Materials Reliability Project Report     ML101660468.
     MRP-169 Technical Basis for Preemptive
     Weld Overlays for Alloy 82/182 Butt
     Welds in PWRs (Revision 1), EPRI, Palo
     Alto, CA: 2012. 1025295.
    NUREG/CR-6933, ``Assessment of Crack     ML071020409.
     Detection in Heavy-Walled Cast
     Stainless Steel Piping Welds Using
     Advanced Low-Frequency Ultrasonic
     Methods''.
    White Paper, PVP2012-78190,              http://
     ``Alternative Acceptance Criteria for    proceedings.asmedigitalcol
     Flaws in Ferritic Steel Components       lection.asme.org/
     Operating in the Upper Shelf             proceeding.aspx?articleid=
     Temperature Range,'' 2012.               1723450.
    White Paper PVP2015-45307, ``Options     http://
     for Defining the Upper Shelf             proceedings.asmedigitalcol
     Transition Temperature (Tc) for          lection.asme.org/
     Ferritic Pressure Vessel Steels,''       proceeding.aspx?articleid=
     2015.                                    2471884.
------------------------------------------------------------------------

List of Subjects in 10 CFR Part 50

    Administrative practice and procedure, Antitrust, Classified 
information, Criminal penalties, Education, Fire prevention, Fire 
protection, Incorporation by reference, Intergovernmental relations, 
Nuclear power plants and reactors, Penalties, Radiation protection, 
Reactor siting criteria, Reporting and recordkeeping requirements, 
Whistleblowing.

    For the reasons set out in the preamble and under the authority of 
the Atomic Energy Act of 1954, as amended; the Energy Reorganization 
Act of 1974, as amended; and 5 U.S.C. 552 and 553, the NRC is adopting 
the following amendments to 10 CFR part 50:

PART 50--DOMESTIC LICENSING OF PRODUCTION AND UTILIZATION 
FACILITIES

0
1. The authority citation for part 50 continues to read as follows:

    Authority:  Atomic Energy Act of 1954, secs. 11, 101, 102, 103, 
104, 105, 108, 122, 147, 149, 161, 181, 182, 183, 184, 185, 186, 
187, 189, 223, 234 (42 U.S.C. 2014, 2131, 2132, 2133, 2134, 2135, 
2138, 2152, 2167, 2169, 2201, 2231, 2232, 2233, 2234, 2235, 2236, 
2237, 2239, 2273, 2282); Energy

[[Page 2354]]

Reorganization Act of 1974, secs. 201, 202, 206, 211 (42 U.S.C. 
5841, 5842, 5846, 5851); Nuclear Waste Policy Act of 1982, sec. 306 
(42 U.S.C. 10226); National Environmental Policy Act of 1969 (42 
U.S.C. 4332); 44 U.S.C. 3504 note; Sec. 109, Pub. L. 96-295, 94 
Stat. 783.


0
2. In Sec.  50.55a, revise paragraphs (a)(3)(i) through (iii) to read 
as follows:


Sec.  50.55a  Codes and standards.

    (a) * * *
    (3) * * *
    (i) NRC Regulatory Guide 1.84, Revision 37. NRC Regulatory Guide 
1.84, Revision 37, ``Design, Fabrication, and Materials Code Case 
Acceptability, ASME Section III,'' dated March 2017, with the 
requirements in paragraph (b)(4) of this section.
    (ii) NRC Regulatory Guide 1.147, Revision 18. NRC Regulatory Guide 
1.147, Revision 18, ``Inservice Inspection Code Case Acceptability, 
ASME Section XI, Division 1,'' dated March 2017, which lists ASME Code 
Cases that the NRC has approved in accordance with the requirements in 
paragraph (b)(5) of this section.
    (iii) NRC Regulatory Guide 1.192, Revision 2. NRC Regulatory Guide 
1.192, Revision 2, ``Operation and Maintenance Code Case Acceptability, 
ASME OM Code,'' dated March 2017, which lists ASME Code Cases that the 
NRC has approved in accordance with the requirements in paragraph 
(b)(6) of this section.
* * * * *

    Dated at Rockville, Maryland, this 2nd day of August 2017.

    For the Nuclear Regulatory Commission.
Brian E. Holian,
Acting Director, Office of Nuclear Reactor Regulation.

    Editorial note:  This document was received for publication by 
the Office of the Federal Register on January 3, 2018.

[FR Doc. 2018-00112 Filed 1-16-18; 8:45 am]
 BILLING CODE P
2332 Federal Register / Vol. 83, No. 11 / Wednesday, January 17, 2018 / Rules and Regulations

alternatives to engineering standards for million (7-percent net present value) to may be used as alternatives to the BPV
the design, construction, ISI, and IST, the NRC. Codes and OM Codes.2
and repair/replacement of nuclear This rulemaking is the latest in a
Table of Contents series of rulemakings that incorporates
power plant components. In this notice,
the NRC also notifies the public of the I. Background by reference new versions of several
availability of RG 1.193, ‘‘ASME Code II. Discussion RGs identifying new, revised, and
Cases Not Approved for Use,’’ Revision A. ASME Code Cases Approved for reaffirmed,3 and unconditionally or
5. The regulatory guide lists Code Cases Unconditional Use conditionally acceptable ASME Code
B. ASME Code Cases Approved for Use Cases that the NRC approves for use. In
that the NRC has not approved for with Conditions
generic use, and will not be developing these RGs, the staff reviews
• ASME BPV Code, Section III Code Cases
incorporated by reference into the (RG 1.84) ASME BPV and OM Code Cases,
NRC’s regulations. • ASME BPV Code, Section XI Code Cases determines the acceptability of each
(RG 1.147) Code Case, and publishes its findings in
The NRC prepared a regulatory
• OM Code Cases (RG 1.192) the RGs. The RGs are revised
analysis (ADAMS Accession No.
C. ASME Code Cases not Approved for Use periodically, as new Code Cases and are
ML16285A013) to identify the benefits (RG 1.193) published by the ASME. The NRC
and costs associated with this final rule. III. Opportunities for Public Participation incorporates by reference the RGs,
The regulatory analysis prepared for this IV. Public Comment Analysis listing acceptable and conditionally
rulemaking was used to determine if the V. Section-by-Section Analysis acceptable ASME Code Cases into
rule is cost-effective, overall, and to VI. Regulatory Flexibility Certification
§ 50.55a. Currently, NRC RG 1.84,
help the NRC evaluate potentially costly VII. Regulatory Analysis
VIII. Backfitting and Issue Finality ‘‘Design, Fabrication, and Materials
conditions placed on specific provisions Code Case Acceptability, ASME Section
of the ASME Code Cases, which are the IX. Plain Writing
X. Environmental Assessment and Final III,’’ Revision 36; RG 1.147, ‘‘Inservice
subject of this rulemaking. Inspection Code Case Acceptability,
Finding of No Significant Environmental
Impact ASME Section XI, Division 1,’’ Revision
TABLE 1—COST-BENEFIT SUMMARY XI. Paperwork Reduction Act 17; and RG 1.192, ‘‘Operation and
XII. Congressional Review Act Maintenance Code Case Acceptability,
Alternative 2—the XIII. Voluntary Consensus Standards
rule alternative net ASME OM Code,’’ Revision 1, are
XIV. Incorporation by Reference—Reasonable incorporated into the NRC’s regulations
benefits (costs) Availability to Interested Parties
Objective (net present in § 50.55a.
value, 7% XV. Availability of Documents
discount rate) II. Discussion
($ million)
I. Background
This rule incorporates by reference
The ASME develops and publishes the latest revisions of the NRC RGs that
Industry ........................... 2.42 the ASME BPV Code, which contains
NRC ................................ 2.52 list ASME BPV and OM Code Cases that
requirements for the design, the NRC finds to be acceptable, or
Net Benefit ...................... 4.94
construction, and ISI and examination acceptable with NRC-specified
of nuclear power plant components, and conditions (‘‘conditionally acceptable’’).
Table 1 summarizes the benefits and ASME’s Nuclear Power Plants (OM) Regulatory Guide 1.84, Revision 37,
costs for the alternative of proceeding Code,1 which contains requirements for supersedes Revision 36; RG 1.147,
with the final rule (Alternative 2) and IST of nuclear power plant components. Revision 18, supersedes Revision 17;
shows that the final rule is In response to BPV Code and OM Code and RG 1.192, Revision 2, supersedes
quantitatively cost-beneficial with a net user requests, the ASME develops Code Revision 1. The NRC also publishes a
benefit of $4.94 million to both the Cases that provide alternatives to BPV document (RG 1.193, ‘‘ASME Code
industry and the NRC when compared Code and OM Code requirements under Cases Not Approved for Use’’) that lists
to the regulatory baseline (Alternative special circumstances. Code Cases that the NRC has not
1). The regulatory analysis shows that The NRC approves and can mandate approved for generic use. The RG 1.193
implementing the final rule is the use of the ASME BPV Codes and is not incorporated by reference into the
quantitatively cost-effective and an OM Codes in § 50.55a, ‘‘Codes and NRC’s regulations; however, in this final
efficient use of the NRC’s and Industry’s standards,’’ through the process of rule, the NRC notes the availability of
resources. Uncertainty analysis shows incorporation by reference. As such, RG 1.193, Revision 5.
that the net benefit ranges from $2.86 each provision of the ASME Codes The ASME Code Cases that are the
million to $6.90 million with a mean of incorporated by reference into and subject of this rulemaking are the new,
$4.94 million. Because the rulemaking mandated by § 50.55a constitutes a revised, and reaffirmed Section III and
alternative is cost-effective, the legally-binding NRC requirement Section XI Code Cases listed in
rulemaking approach is recommended. imposed by the regulations. As noted
There are several benefits associated previously, ASME Code Cases, for the 2 See Federal Register notice, ‘‘Incorporation by

with this final rule. Under this final most part, represent alternative Reference of ASME BPV and OM Code Cases’’ (68
approaches for complying with FR 40469; July 8, 2003).
rule, a licensee of a nuclear power plant 3 Code Cases are categorized by ASME as one of
would no longer be required to submit provisions of the ASME BPV Codes and three types: new, revised, or reaffirmed. A new
a Code Case alternative request under OM Codes. Accordingly, the NRC Code Case provides for a new alternative to specific
the new § 50.55a(z) of Title 10 of the periodically amends § 50.55a to ASME Code provisions or addresses a new need.
incorporate by reference the NRC’s RGs The ASME defines a revised Code Case to be a
Code of Federal Regulations (10 CFR),
ethrower on DSK3G9T082PROD with RULES

revision (modification) to an existing Code Case to
which would provide an averted cost of listing approved ASME Code Cases that address, for example, technological advancements
$7.75 million (7-percent net present in examination techniques or to address NRC
1 The editions and addenda of the ASME Code for conditions imposed in one of the RGs that have
value) to the licensee. Additionally, the
Operation and Maintenance of Nuclear Power been incorporated by reference into § 50.55a. The
NRC would not receive Code Case Plants have had different titles from 2005 to 2012, ASME defines ‘‘reaffirmed’’ as an OM Code Case to
alternative request submittals, which and are referred to collectively in this rule as the be one that does not have any change to technical
would provide an averted cost of $2.52 ‘‘OM Code.’’ content, but includes editorial changes.

VerDate Sep<11>2014 14:56 Jan 16, 2018 Jkt 244001 PO 00000 Frm 00004 Fmt 4700 Sfmt 4700 E:\FR\FM\17JAR1.SGM 17JAR1
Federal Register / Vol. 83, No. 11 / Wednesday, January 17, 2018 / Rules and Regulations 2333

Supplement 11 to the 2007 BPV Code standards. The Code Case process use, without conditions as addressed in
through Supplement 10 to the 2010 BPV includes the development of a technical Section A of this document; subject to
Code, and the OM Code Cases published justification in support of each new or the specified conditions, or as identified
with the 2009 Edition through the 2012 revised Code Case. The ASME in Section B of this document. The staff
Edition. committee meetings are open to the reviewed the new, revised, and
The latest editions and addenda of the public and attendees are encouraged to reaffirmed Code Cases identified in the
ASME BPV and OM Codes that the NRC participate. Task groups, working three RGs being incorporated by
has approved for use are referenced in groups, and subgroups report to reference into § 50.55a in this
§ 50.55a. The ASME also publishes respective standards committees. The rulemaking. Therefore, the NRC
Code Cases that provide alternatives to standards committee is the decisive approves revising the § 50.55a
existing Code requirements that the consensus committee in that it ensures regulations to incorporate by reference
ASME developed and approved. This that the development process fully the latest revisions of RGs 1.84, 1.147,
rule incorporates by reference the latest complies with the ANSI consensus and 1.192. Additionally, the NRC
revisions of RGs 1.84, 1.147, and 1.192. process. announces the availability of the latest
This rule allows nuclear power plant Second, the standards committee revision of RG 1.193.
licensees and applicants for transmits a first consideration letter
construction permits, operating licenses, ballot to every member of the standards A. ASME Code Cases Approved for
combined licenses, standard design committee, requesting comment or Unconditional Use
certifications, standard design approval of new and revised Code The Code Cases that are discussed in
approvals, and manufacturing licenses, Cases. Code Cases are approved by the Table I are new, revised, or reaffirmed
under the regulations that govern standards committee from the first Code Cases that the NRC is approving
license certifications, to voluntarily use consideration letter ballot when: (1) At for use without conditions. The NRC
the Code Cases listed in these RGs as least two thirds of the eligible consensus concludes, in accordance with the
suitable alternatives to certain committee membership vote approved; process described for review of ASME
provisions of the ASME BPV and OM (2) there are no disapprovals from the Code Cases, that each of the ASME Code
Codes for the construction, ISI, and IST standards committee; and (3) no Cases listed in Table I are acceptable for
of nuclear power plant components. substantive comments are received from use without conditions. Therefore, the
This action is consistent with the the ASME oversight committees such as NRC is approving for unconditional use
provisions of the National Technology the Technical Oversight Management the Code Cases listed in Table I. This
Transfer and Advancement Act of 1995 Committee (TOMC). The TOMC’s table identifies the regulatory guide the
(NTTAA), Public Law 104–113, which duties, in part, are to oversee various applicable Code Case that the NRC is
encourages Federal regulatory agencies standards committees to ensure approving for use.
to consider adopting industry consensus technical adequacy and to provide The NRC revised RG 1.147, Revision
standards as an alternative to de novo recommendations in the development of 18 to approve Code Case N–786–1 in
agency development of standards codes and standards, as required. Code Table 1 to address inconsistencies that
affecting an industry. This action is also Cases that were disapproved or received were identified between the NRC’s
consistent with the NRC policy of substantive comments from the first position in the proposed rule regarding
evaluating the latest versions of consideration ballot are reviewed by the the acceptability of Code Case N–786
consensus standards, in terms of their working level group(s) responsible for and several licensee requests for
suitability for endorsement by their development to consider the alternatives to ASME Code
regulations or regulatory guides. comments received. These Code Cases requirements, in accordance with Title
The NRC follows a three-step process are approved by the standards 10 of the Code of Federal Regulations
to determine acceptability of new, committee on second consideration (10 CFR) 50.55a(z), that have utilized
revised, and reaffirmed Code Cases, and when at least two thirds of the eligible Code Case N–786. The NRC had
the need for regulatory positions on the consensus committee membership vote authorized the use of Code Case N–786
use of these Code Cases. This process approved, and there are no more than with modifications. The NRC erred in
was employed in the review of the Code three disapprovals from the consensus not listing N–786 in DG–1296, Table 2
Cases in Supplement 11 to the 2007 committee. ‘‘Conditionally Acceptable Section XI
Edition through Supplement 10 to the Third, the NRC reviews new, revised, Code Cases’’ with appropriate
2010 Edition of the BPV Code and the and reaffirmed Code Cases to determine conditions, in order to be consistent
2009 Edition through the 2012 Edition their acceptability for incorporation by with modifications that the NRC has
of the OM Code. The Code Cases in reference in § 50.55a through the subject required for requested alternatives based
these supplements and OM Editions and RGs. This rulemaking process, when on Code Case N–786. In response to
Addenda are the subject of this rule. considered together with the ANSI modifications to N–786 by licensees
First, the ASME develops Code Cases process for developing and approving requesting to use this code case as an
through a consensus development the ASME codes and standards, and alternative to ASME Code, ASME
process, as administered by the Code Cases, constitutes the NRC’s basis revised the code case. The revised Code
American National Standards Institute that the Code Cases (with conditions as Case, N–786–1 ‘‘Alternative
(ANSI), which ensures that the various necessary) provide reasonable assurance Requirements for Sleeve Reinforcement
technical interests (e.g., utility, of adequate protection to public health of Class 2 and 3 Moderate-Energy
manufacturing, insurance, regulatory) and safety. Carbon Steel Piping Section XI, Division
are represented on standards The staff concludes, in accordance 1,’’ includes modifications that address
with the process described, that the all of the NRC’s concerns that the NRC
ethrower on DSK3G9T082PROD with RULES

development committees and that their
view points are addressed fairly. The Code Cases are technically adequate identified in previously approved
NRC staff actively participates in (with conditions as necessary) and alternatives that were based on N–786.
discussions and technical debates of the consistent with current NRC Therefore, the NRC has listed Code Case
task groups, working groups, subgroups, regulations, and the staff is referencing N–786–1 in Table 1 of RG 1.147
and standards committees regarding the these Code Cases in the applicable RGs, Revision 18 in lieu of code Case N–786.
development of new and revised thereby approving them for voluntary There were no public comments

VerDate Sep<11>2014 14:56 Jan 16, 2018 Jkt 244001 PO 00000 Frm 00005 Fmt 4700 Sfmt 4700 E:\FR\FM\17JAR1.SGM 17JAR1
2334 Federal Register / Vol. 83, No. 11 / Wednesday, January 17, 2018 / Rules and Regulations

received on the inclusion of N–786 in in this final rule because it includes the conditions on the use of this method of
the RG. Code Case N–786–1 is included latest ASME guidance and the NRC repair.

TABLE I—ASME CODE CASES APPROVED FOR UNCONDITIONAL USE
Code Case No. Supplement Title

Boiler and Pressure Vessel Code Section III
(addressed in RG 1.84, Revision 37, Table 1)

N–284–3 .......................................... 7 (10 Edition) ................................. Metal Containment Shell Buckling Design Methods, Class MC, TC,
and SC Construction, Section III, Divisions 1 and 3.
N–500–4 .......................................... 8 (10 Edition) ................................. Alternative Rules for Standard Supports for Classes 1, 2, 3, and MC,
Section III, Division 1.
N–520–5 .......................................... 10 (10 Edition) ............................... Alternative Rules for Renewal of Active or Expired N-type Certificates
for Plants Not in Active Construction, Section III, Division 1.
N–594–1 .......................................... 8 (10 Edition) ................................. Repairs to P–4 and P–5A Castings without Postweld Heat Treatment
Class 1, 2, and 3 Construction, Section III, Division 1.
N–637–1 .......................................... 3 (10 Edition) ................................. Use of 44Fe–25Ni–21Cr–Mo (Alloy UNS N08904) Plate, Bar, Fittings,
Welded Pipe, and Welded Tube, Classes 2 and 3, Section III, Divi-
sion 1.
N–655–2 .......................................... 4 (10 Edition) ................................. Use of SA–738, Grade B, for Metal Containment Vessels, Class MC,
Section III, Division 1.
N–763 .............................................. 2 (10 Edition) ................................. ASTM A 709–06, Grade HPS 70W (HPS 485W) Plate Material With-
out Postweld Heat Treatment as Containment Liner Material or
Structural Attachments to the Containment Liner, Section III, Divi-
sion 2.
N–777 .............................................. 4 (10 Edition) ................................. Calibration of Cv Impact Test Machines, Section III, Divisions 1, 2,
and 3.
N–785 .............................................. 11 (07 Edition) ............................... Use of SA–479/SA–479M, UNS S41500 for Class 1 Welded Con-
struction, Section III, Division 1.
N–811 .............................................. 7 (10 Edition) ................................. Alternative Qualification Requirements for Concrete Level III Inspec-
tion Personnel, Section III, Division 2.
N–815 .............................................. 8 (10 Edition) ................................. Use of SA–358/SA–358M Grades Fabricated as Class 3 or Class 4
Welded Pipe, Class CS Core Support Construction, Section III, Di-
vision 1.
N–816 .............................................. 8 (10 Edition) ................................. Use of Temper Bead Weld Repair Rules Adopted in 2010 Edition and
Earlier Editions, Section III, Division 1.
N–817 .............................................. 8 (10 Edition) ................................. Use of Die Forgings, SB–247, UNS A96061 Class T6, With Thick-
ness ≤ 4.000 in. Material, Class 2 Construction (1992 Edition or
Later), Section III, Division 1.
N–819 .............................................. 8 (10 Edition) ................................. Use of Die Forgings, SB–247, UNS A96061 Class T6, With Thick-
ness ≤ 4.000 in. Material, Class 2 Construction (1989 Edition with
the 1991 Addenda or Earlier), Section III, Division 1.
N–822 .............................................. 8 (10 Edition) ................................. Application of the ASME Certification Mark, Section III, Divisions 1, 2,
3, and 5.

Boiler and Pressure Vessel Code Section XI
(addressed in RG 1.147, Revision 18, Table 1)

N–609–1 .......................................... 3 (10 Edition) ................................. Alternative Requirements to Stress-Based Selection Criteria for Cat-
egory B–J Welds, Section XI, Division 1.
N–613–2 .......................................... 4 (10 Edition) ................................. Ultrasonic Examination of Full Penetration Nozzles in Vessels, Exam-
ination Category B–D, Reactor Nozzle-To-Vessel Welds, and Noz-
zle Inside Radius Section Figs. IWB–2500–7(a), (b), (c), and (d),
Section XI, Division 1.
N–652–2 .......................................... 9 (10 Edition) ................................. Alternative Requirements to Categorize B–G–1, B–G–2, and C–D
Bolting Examination Methods and Selection Criteria, Section XI, Di-
vision 1.
N–653–1 .......................................... 9 (10 Edition) ................................. Qualification Requirements for Full Structural Overlaid Wrought Aus-
tenitic Piping Welds, Section XI, Division 1.
N–694–2 4 ........................................ 1 (13 Edition) ................................. Evaluation Procedure and Acceptance Criteria for [pressurized water
reactors] (PWR) Reactor Vessel Head Penetration Nozzles, Sec-
tion XI, Division 1.
N–730–1 .......................................... 10 (10 Edition) ............................... Roll Expansion of Class 1 Control Rod Drive Bottom Head Penetra-
tions in [boiling water reactors] BWRs, Section XI, Division 1.
N–769–2 .......................................... 10 (10 Edition) ............................... Roll Expansion of Class 1 In-Core Housing Bottom Head Penetra-
tions in BWRs, Section XI, Division 1.
N–771 .............................................. 7 (10 Edition) ................................. Alternative Requirements for Additional Examinations of Class 2 or 3
ethrower on DSK3G9T082PROD with RULES

Items, Section XI, Division 1.
N–775 .............................................. 2 (10 Edition) ................................. Alternative Requirements for Bolting Affected by Borated Water Leak-
age, Section XI, Division 1.
N–776 .............................................. 1 (10 Edition) ................................. Alternative to IWA–5244 Requirements for Buried Piping, Section XI,
Division 1.
N–786–1 .......................................... 5 (10 Edition) ................................. Alternative Requirements for Sleeve Reinforcement of Class 2 and 3
Moderate-Energy Carbon Steel Piping, Section XI, Division 1.

VerDate Sep<11>2014 14:56 Jan 16, 2018 Jkt 244001 PO 00000 Frm 00006 Fmt 4700 Sfmt 4700 E:\FR\FM\17JAR1.SGM 17JAR1
Federal Register / Vol. 83, No. 11 / Wednesday, January 17, 2018 / Rules and Regulations 2335

TABLE I—ASME CODE CASES APPROVED FOR UNCONDITIONAL USE—Continued
Code Case No. Supplement Title

N–798 .............................................. 4 (10 Edition) ................................. Alternative Pressure Testing Requirements for Class 1 Piping Be-
tween the First and Second Vent, Drain, and Test Isolation De-
vices, Section XI, Division 1.
N–800 .............................................. 4 (10 Edition) ................................. Alternative Pressure Testing Requirements for Class 1 Piping Be-
tween the First and Second Injection Valves, Section XI, Division 1.
N–803 .............................................. 5 (10 Edition) ................................. Similar and Dissimilar Metal Welding Using Ambient Temperature
Automatic or Machine Dry Underwater Laser Beam Welding
(ULBW) Temper Bead Technique, Section XI, Division 1.
N–805 .............................................. 6 (10 Edition) ................................. Alternative to Class 1 Extended Boundary End of Interval or Class 2
System Leakage Testing of the Reactor Vessel Head Flange O-
Ring Leak-Detection System, Section XI, Division 1.
N–823 .............................................. 9 (10 Edition) ................................. Visual Examination, Section XI, Division 1.
N–825 5 ............................................ 3 (13 Edition) ................................. Alternative Requirements for Examination of Control Rod Drive Hous-
ing Welds, Section XI, Division 1.
N–845 6 ............................................ 6 (13 Edition) ................................. Qualification Requirements for Bolts and Studs, Section XI, Division
1.

Operation and Maintenance Code (OM)
(addressed in RG 1.192, Revision 2, Table 1)

OMN–2 ............................................ 2012 Edition ................................... Thermal Relief Valve Code Case, OM Code-1995, Appendix I.
OMN–5 ............................................ 2012 Edition ................................... Testing of Liquid Service Relief Valves without Insulation.
OMN–6 ............................................ 2012 Edition ................................... Alternative Rules for Digital Instruments.
OMN–7 ............................................ 2012 Edition ................................... Alternative Requirements for Pump Testing.
OMN–8 ............................................ 2012 Edition ................................... Alternative Rules for Preservice and Inservice Testing of Power-Op-
erated Valves That Are Used for System Control and Have a Safe-
ty Function per OM–10, ISTC–1.1, or ISTA–1100.
OMN–13, Revision 2 ....................... 2012 Edition ................................... Performance-Based Requirements for Extending Snubber Inservice
Visual Examination Interval at [light water reactor] LWR Power
Plants.
OMN–14 .......................................... 2012 Edition ................................... Alternative Rules for Valve Testing Operations and Maintenance, Ap-
pendix I: BWR [control rod drive] CRD Rupture Disk Exclusion.
OMN–15, Revision 2 ....................... 2012 Edition ................................... Performance-Based Requirements for Extending the Snubber Oper-
ational Readiness Testing Interval at LWR Power Plants.
OMN–17 .......................................... 2012 Edition ................................... Alternative Rules for Testing ASME Class 1 Pressure Relief/Safety
Valves.

B. ASME Code Cases Approved for Use those Code Cases must be supplemented and the supplemental information
With Conditions in order to provide an acceptable level needed to provide clarity. These ASME
The Code Cases that are discussed in of quality and safety. Accordingly, the Code Cases with conditions are
Table II, below, are new, revised or NRC is imposing conditions on the use included in Table 2 of each RG (i.e., RG
reaffirmed Code Cases, which the NRC of these Code Cases to modify, limit, or 1.84, RG 1.147, and RG 1.192). It is
is approving for use with conditions. clarify their requirements. The noted that both RG 1.147 and RG 1.192
The NRC has determined that certain conditions specify, for each applicable have new ASME Code Cases with
Code Cases, as issued by the ASME, are Code Case, the additional activities that conditions; however, there are no new
generally acceptable for use, but that the must be performed, the limits on the ASME Code Cases with conditions for
alternative requirements specified in activities specified in the Code Case, RG 1.84.

TABLE II—CODE CASES APPROVED FOR CONDITIONAL USE
Code Case No. Supplement Title

Boiler and Pressure Vessel Code Section III
(addressed in RG 1.84, Revision 37, Table 2)

No ASME Section III Code Cases are approved for conditional use in this rule.
Boiler and Pressure Vessel Code Section XI
(addressed in RG 1.147, Revision 18, Table 2)

N–552–1 .......................................... 10 (10 Edition) ............................... Alternative Methods—Qualification for Nozzle Inside Radius Section
from the Outside Surface, Section XI, Division 1.
ethrower on DSK3G9T082PROD with RULES

N–576–2 .......................................... 9 (10 Edition) ................................. Repair of Class 1 and 2 SB–163, UNS N06600 Steam Generator
Tubing, Section XI, Division 1.
N–593–2 .......................................... 8 (10 Edition) ................................. Examination Requirements for Steam Generator Nozzle-to-Vessel
Welds, Section XI, Division 1.

4 Code Case published in Supplement 1 to the 5 Code Case published in Supplement 3 to the 6 Code Case published in Supplement 6 to the

2013 Edition; included at the request of ASME. 2013 Edition; included at the request of ASME. 2013 Edition; included at the request of ASME.

VerDate Sep<11>2014 14:56 Jan 16, 2018 Jkt 244001 PO 00000 Frm 00007 Fmt 4700 Sfmt 4700 E:\FR\FM\17JAR1.SGM 17JAR1
2336 Federal Register / Vol. 83, No. 11 / Wednesday, January 17, 2018 / Rules and Regulations

TABLE II—CODE CASES APPROVED FOR CONDITIONAL USE—Continued
Code Case No. Supplement Title

N–638–6 .......................................... 6 (10 Edition) ................................. Similar and Dissimilar Metal Welding Using Ambient Temperature
Machine GTAW Temper Bead Technique, Section XI, Division 1.
N–662–1 .......................................... 6 (10 Edition) ................................. Alternative Repair/Replacement Requirements for Items Classified in
Accordance with Risk-Informed Processes, Section XI, Division 1.
N–666–1 .......................................... 9 (10 Edition) ................................. Weld Overlay of Classes 1, 2, and 3 Socket Welded Connections,
Section XI, Division 1.
N–749 .............................................. 9 (10 Edition) ................................. Alternative Acceptance Criteria for Flaws in Ferritic Steel Compo-
nents Operating in the Upper Shelf Temperature Range, Section
XI, Division 1.
N–754 .............................................. 6 (10 Edition) ................................. Optimized Structural Dissimilar Metal Weld Overlay for Mitigation of
PWR Class 1 Items, Section XI, Division 1.
N–778 .............................................. 6 (10 Edition) ................................. Alternative Requirements for Preparation and Submittal of Inservice
Inspection Plans, Schedules, and Preservice and Inservice Sum-
mary Reports, Section XI, Division 1.
N–789 .............................................. 6 (10 Edition) ................................. Alternative Requirements for Pad Reinforcement of Class 2 and 3
Moderate Energy Carbon Steel Piping for Raw Water Service, Sec-
tion XI, Division 1.
N–795 .............................................. 3 (10 Edition) ................................. Alternative Requirements for BWR Class 1 System Leakage Test
Pressure Following Repair/Replacement Activities, Section XI, Divi-
sion 1.
N–799 .............................................. 4 (10 Edition) ................................. Dissimilar Metal Welds Joining Vessel Nozzles to Components, Sec-
tion XI, Division 1.

Operation and Maintenance Code (OM)
(addressed in RG 1.192, Revision 2, Table 2)

OMN–1 Revision 1 .......................... 2012 Edition ................................... Alternative Rules for Preservice and Inservice Testing of Active Elec-
tric Motor Operated-Valve Assemblies in Light-Water Reactor
Power Plants.
OMN–3 ............................................ 2012 Edition ................................... Requirements for Safety Significance Categorization of Components
Using Risk Insights for Inservice Testing of LWR Power Plants.
OMN–4 ............................................ 2012 Edition ................................... Requirements for Risk Insights for Inservice Testing of Check Valves
at LWR Power Plants.
OMN–9 ............................................ 2012 Edition ................................... Use of a Pump Curve for Testing.
OMN–12 .......................................... 2012 Edition ................................... Alternative Requirements for Inservice Testing Using Risk Insights for
Pneumatically and Hydraulically Operated Valve Assemblies in
Light-Water Reactor Power Plants (OM-Code 1998, Subsection
ISTC).
OMN–16 Revision 1 ........................ 2012 Edition ................................... Use of a Pump Curve for Testing.
OMN–18 .......................................... 2012 Edition ................................... Alternate Testing Requirements for Pumps Tested Quarterly Within
±20% of Design Flow.
OMN–19 .......................................... 2012 Edition ................................... Alternative Upper Limit for the Comprehensive Pump Test.
OMN–20 .......................................... 2012 Edition ................................... Inservice Test Frequency.

The NRC’s evaluation of the Code Title: Alternative Methods— in Revision 17 of RG 1.147 in October
Cases and the reasons for the NRC’s Qualification for Nozzle Inside Radius 2014. The reasons for imposing these
conditions are discussed in the Section from the Outside Surface, conditions are not resolved by Code
following paragraphs. Notations have Section XI, Division 1. Case N–576–2 and, therefore, these
been made to indicate the conditions The conditions on Code Case N–552– conditions have been retained in
duplicated from previous versions of the 1 are identical to the conditions on N– Revision 18 of RG 1.147.
RG. 552 that were approved by the NRC in
Revision 16 of RG 1.147 in October Public comments on N–576–2
ASME BPV Code, Section III Code Cases 2010. The reasons for imposing these requested that the NRC revise the
(RG 1.84) conditions in Code Case N–576 proposed condition to follow IWA–4200
continue to apply to N–576–2. in their code of record. In response, the
There are no new or revised Section Therefore, these conditions have been NRC revised the ‘‘note’’ in the condition
III Code Cases in Supplement 11 to the retained for this Code Case in Revision in Revision 18 of RG 1.147 to eliminate
2007 Edition through Supplement 10 to 18 of RG 1.147. the portion regarding reconciliation.
the 2010 Edition that the NRC is The revised ‘‘note’’ will read: ‘‘Note:
conditionally approving in Revision 37 Code Case N–576–2 [Supplement 9,
Steam generator tube repair methods
of RG 1.84. 2010 Edition]
require prior NRC approval through the
ethrower on DSK3G9T082PROD with RULES

Type: Revised. Technical Specifications. This Code
ASME BPV Code, Section XI Code Cases Title: Repair of Class 1 and 2 SB–163,
(RG 1.147) Case does not address certain aspects of
UNS N06600 Steam Generator Tubing,
this repair, e.g., the qualification of the
Code Case N–552–1 [Supplement 10, Section XI, Division 1.
The conditions on Code Case N–576– inspection and plugging criteria
2010 Edition] necessary for staff approval of the repair
2 are identical to the conditions on N–
Type: Revised. 576–1 that were approved by the NRC method.’’

VerDate Sep<11>2014 14:56 Jan 16, 2018 Jkt 244001 PO 00000 Frm 00008 Fmt 4700 Sfmt 4700 E:\FR\FM\17JAR1.SGM 17JAR1
Federal Register / Vol. 83, No. 11 / Wednesday, January 17, 2018 / Rules and Regulations 2337

Code Case N–593–2 [Supplement 8, Code Case N–638–6 [Supplement 6, thickness and the previously stated
2010 Edition] 2010 Edition] condition will limit repairs to this
Type: Revised. previously approved value. Repairs
Type: Revised. exceeding one-half of the ferritic base
Title: Examination Requirements for Title: Similar and Dissimilar Metal
Welding Using Ambient Temperature metal thickness may represent
Steam Generator Nozzle-to-Vessel significant repairs (e.g., replacement of
Welds, Section XI, Division 1. Machine GTAW Temper Bead
Technique, Section XI, Division 1. an entire portion of the reactor coolant
The first condition on Code Case N– Code Case N–638–6 allows the use of loop). At the time that this revision of
593–2 is identical to the condition on the automatic or machine gas-tungsten the Code Case was approved by ASME,
Code Case N–593 that was first arc welding (GTAW) temper bead the NRC staff had concerns related to
approved by the NRC in Revision 13 of technique. The GTAW is a proven through-wall repairs. Subsequently,
RG 1.147 in June 2003. The condition method that can produce high-quality through further evaluation related to a
stated that, ‘‘Essentially 100 percent (not welds because it affords greater control separate rulemaking, the NRC resolved
less than 90 percent) of the examination over the weld area than many other its concerns related to through-wall
volume A–B–C–D–E–F–G–H [in Figure welding processes. repairs. Therefore, the NRC determined
1 of the Code Case] must be examined.’’ The NRC first approved Code Case N– that proposed Condition (2) is
The reasons for imposing this condition 638 (Revision 0) in 2003 (Revision 13 of unnecessary and has removed this
in Code Case N–593 continue to apply RG 1.147). Code Case N–638–4 was condition from the final RG 1.147,
to Code Case N–593–2. Therefore, this approved by the NRC in Revision 16 of Revision 18.
condition has been retained for this RG 1.147 with two conditions. Code
Code Case in Revision 18 of RG 1.147. Code Case N–662–1 [Supplement 6,
Case N–638–5 was not approved in RG 2010 Edition]
The second condition on Code Case 1.147 for generic use but has been
N–593–2 is new. Revision 2 of the Code Type: Revised.
approved through requests for an Title: Alternative Repair/Replacement
Case reduces the weld examination alternative to § 50.55a. Code Case N–
volume by reducing the width examined Requirements for Items Classified in
638–6 resolves one of the NRC’s Accordance with Risk-Informed
on either side of the weld from ts/2 to concerns that were raised when Code
1⁄2 in. The basis for this change in Processes, Section XI, Division 1.
Case N–638–4 was considered for The condition on Code Case N–662–
inspection volume is to revise the approval and, therefore, the NRC is
examination volume for steam generator 1 is identical to the condition on N–662
deleting that condition from RG 1.147. that was approved by the NRC in
nozzle-to-vessel welds (under Code Case Many of the provisions for developing
N–593–2) to be consistent with that Revision 16 of RG 1.147 in October
and qualifying welding procedure 2010. The reasons for imposing this
specified in Code Case N–613–1 for specifications for the temper bead
similar vessel nozzles. condition were not resolved by Code
technique that were contained in earlier Case N–662–1. Therefore, this condition
The NRC identified an issue with versions of the Code Case have been has been retained for this Code Case in
respect to Code Case N–593–2 regarding incorporated into ASME Section IX, Revision 18 of RG 1.147.
its inconsistency with Code Case N– ‘‘Welding and Brazing Qualifications,’’
613–1. Code Case N–593–2 and Code QW–290, ‘‘Temper Bead Welding.’’ Code Case N–666–1 [Supplement 9,
Case N–613–1 address certain types of Code Case N–638–6 retains the 2010 Edition]
nozzle-to-vessel welds. Code Case N– provisions not addressed by QW–290 Type: Revised.
613–1 states that ‘‘. . . Category B–D and references QW–290 in lieu of Title: Weld Overlay of Classes 1, 2,
nozzle-to-vessel welds previously specifying them directly in the Code and 3 Socket Welded Connections,
ultrasonically examined using the Case. Section XI, Division 1.
examination volumes of Figs. IWB– In addition to retaining one of the two Code Case N–666 was
2500–7(a), (b), and (c) may be examined conditions on Code Case N–638–4, the unconditionally approved in Revision
using the reduced examination volume NRC considered adding a new condition 17 of RG 1.147. The NRC approves Code
(A–B–C–D–E–F–G–H) of Figs. 1, 2, and to address technical issues raised by Case N–666–1 with one condition.
3.’’ The keywords are ‘‘previously certain provisions of Code Case N–638– The condition is that a surface
examined.’’ Code Case N–613–1 6. examination must be performed on the
requires the larger volume to have been The retained condition on Code Case completed weld overlay for Class 1 and
previously examined before N–638–6 pertains to the qualification of Class 2 piping socket welds. Code Case
examinations using the reduced volume nondestructive evaluation (NDE) and is N–666–1 contains provisions for the
can be performed. This ensures that identical to the condition on N–638–4 design, installation, evaluation, pressure
there are no detrimental flaws in the that was approved by the NRC in testing, and examination of the weld
component adjacent to the weld that Revision 17 of RG 1.147 in October overlays on Class 1, 2, and 3 socket
would be missed if the inspection was 2014. The reasons for imposing this welds. Section 5(a)(1) of the Code Case
performed only on the reduced volume. condition in Code Case N–638 continue requires NDE of the completed weld
However, Code Case N–593–2 allows a to apply to N–638–6. Therefore, this overlay in accordance with the
licensee to immediately implement the condition has been retained in Revision Construction Code. However, various
reduced volume. Accordingly, the NRC 18 of RG 1.147. Construction Codes have been used in
is approving Code Case N–593–2 with a The new proposed condition (2) states the design and fabrication of the nuclear
condition to require that the that section 1(b)(1) of the Code Case power plant fleet. The requirements for
examination volume specified in shall not be used. Section 1(b)(1) would NDE have changed over the years, as
ethrower on DSK3G9T082PROD with RULES

Section XI, Table IWB–2500–1, allow through-wall circumferential more effective and reliable methods and
Examination Category B–D, be used for repair welds to be made using the techniques have been developed. In
the examination of steam generator temper bead technique without heat addition, Construction Code practices
nozzle-to-vessel welds at least once treatment. Revisions 1 through 5 of N– have evolved based on design and
prior to use of the reduced volume, as 638 limited the depth of the weld to construction experience. The NRC is
allowed by the Code Case. one-half of the ferritic base metal concerned that some of the Construction

VerDate Sep<11>2014 14:56 Jan 16, 2018 Jkt 244001 PO 00000 Frm 00009 Fmt 4700 Sfmt 4700 E:\FR\FM\17JAR1.SGM 17JAR1
2338 Federal Register / Vol. 83, No. 11 / Wednesday, January 17, 2018 / Rules and Regulations

Codes would not require a surface Additionally, the NRC defines based on a 2015 ASME Pressure Vessels
examination of the weld overlay and temperature Tc1 below, which the linear and Piping Conference paper (PVP2015–
would, therefore, be inadequate for NDE elastic fracture mechanics (LEFM) 45307) by Mark Kirk, Gary Stevens,
of the completed weld overlay. The NRC method must be applied: Marjorie Erickson, William Server, and
believes that a VT–1 examination alone Tc1 = 95.36 °F + 0.703 × RTNDT (in U.S Hal Gustin entitled, ‘‘Options for
would not be adequate and that a Customary Units), and Defining the Upper Shelf Transition
surface or volumetric examination must Tc1 = 47.7 °C + 0.703 × RTNDT (in Temperature (Tc) for Ferritic Pressure
be performed on the completed weld International System (SI) Units). Vessel Steels,’’ where Tc and Tc1 are
overlay for Class 1 and Class 2 piping Between Tc1 and Tc, while the fracture defined as the intersections of specific
socket welds. Fabrication defects must mode is in transition from LEFM to toughness curves of LEFM data and
be dispositioned using the surface or EPFM, users should consider whether or EPFM data, as shown in that paper.
volumetric examination criteria of the not it is appropriate to apply the EPFM Using the model in the 2015 PVP paper
Construction Code, as identified in the method. Alternatively, the licensee may is justified because, in addition to its
Repair/Replacement Plan. use a different Tc value, if it can be theoretically motivated approach in
Public commenters requested that the justified by plant-specific Charpy applying the temperature-dependent
words ‘‘and seal weld’’ be removed from curves. flow behavior of body-centered cubic
the condition because the phrase Code Case N–749 provides acceptance materials, the model is also supported
implies that the seal weld requires criteria for flaws in ferritic components by numerous LEFM data and 809 EPFM
surface examination in addition to for conditions when the material data in the upper shelf region.
surface examination of the final overlay. While the Tc proposed in Code Case
fracture resistance will be controlled by
The Code Case requires a visual N–749 is conservative based on the
upper-shelf toughness behavior. These
examination of the seal weld, remaining intersection of the mean curves of the
procedures may be used to accept a flaw
socket weld, and adjacent base material two sets of data, the NRC determined
in lieu of the requirements in Section
before the weld overlay can be applied, that actual or bounding properties (on
XI, paragraphs IWB–3610 and IWB–
which the NRC has determined is the the conservative side) should be used
3620, which use LEFM to evaluate flaws instead of mean material properties for
appropriate examination prior to the that exceed limits of Section XI,
application of the weld overlay. evaluating flaws detected in a ferritic
paragraph IWB–3500. Code Case N–749 component using the EPFM approach.
Therefore, proposed Condition (1) has employs EPFM methods (J-integral) and
been revised to remove ‘‘and seal weld.’’ This will prevent inaccurate component
is patterned after the fracture failure predictions using the EPFM
In the proposed rule, the NRC methodology and acceptance criteria
included a second condition, which approach, due to overestimated material
that currently exist in Section XI, properties. Further, the NRC’s approach
required that if a surface or volumetric paragraph IWB–3730(b), and Section XI,
examination of the completed weld considers the temperature range for
Nonmandatory Appendix K, fracture mode transition between LEFM
overlay was not required by the plant- ‘‘Assessment of Reactor Vessels with
specific Construction Code, that a VT– and EPFM. Based on the previous
Upper Shelf Charpy Impact Energy discussion, the NRC is imposing a
1 visual examination be performed of Levels.’’ The Code Case states that the
the weld overlay. Paragraph 5(a) of the condition on the use of Code Case N–
proposed methodology is applicable if 749 that: (1) The two equations for Tc be
Code Case requires ‘‘visual and the metal temperature of the component
nondestructive examination of the final used instead of Tc, as proposed in the
exceeds the upper shelf transition Code Case for requiring EPFM
structural overlay weld.’’ Paragraph temperature, Tc, which is defined as nil-
5(a)(1) of the Code Case specifically application, when the temperature is
ductility reference temperature (RTNDT) above Tc, and (2) the two equations for
requires a VT–1 visual examination of plus 105 degrees F. The justification for
the completed weld overlay. Public Tc1 be used for requiring LEFM
this, as documented in the underlying application when temperature is below
commenters requested that the NRC White Paper, PVP2012–78190,
remove the second condition because it Tc1. Between Tc1 and Tc, while the
‘‘Alternative Acceptance Criteria for fracture mode is in transition between
was redundant and unnecessary. The Flaws in Ferritic Steel Components
NRC staff agrees and thus Condition (2) LEFM and EPFM, users should consider
Operating in the Upper Shelf whether or not it is appropriate to apply
has been removed from the final rule. Temperature Range,’’ is that the ASME the EPFM method.
Code Case N–749 [Supplement 9, 2010 BPV Code, Section XI, K1c curve will Alternatively, the licensee may use a
Edition] give a (T¥ RTNDT) value of 105 degrees different Tc value, if it can be justified
F at K1c of 200 ksi√inch. by plant-specific Charpy curves.
Type: New. Defining an upper shelf transition
Title: Alternative Acceptance Criteria temperature purely based on LEFM data Code Case N–754 [Supplement 6, 2010
for Flaws in Ferritic Steel Components is not convincing because it ignores Edition]
Operating in the Upper Shelf EPFM data and Charpy data and their Type: New.
Temperature Range, Section XI, relationship to the LEFM data. The NRC Title: Optimized Structural Dissimilar
Division 1. staff performed calculations on several Metal Weld Overlay for Mitigation of
The NRC has determined that instead randomly selected reactor pressure PWR Class 1 Items, Section XI, Division
of the upper shelf transition vessel surveillance materials with high 1.
temperature, Tc, as defined in the Code upper-shelf energy values and low The NRC approves Code Case N–754
Case, the following shall be used: RTNDT values from three plants and with three conditions. Code Case N–754
Tc = 154.8 °F + 0.82 × RTNDT (in U.S provides requirements for installing
ethrower on DSK3G9T082PROD with RULES

found that using Tc, as defined in the
Customary Units), and Code Case, is nonconservative because optimized structural weld overlays
Tc = 82.8 °C + 0.82 × RTNDT (in at the temperature of RTNDT + 105 (OWOL) on the outside surface of ASME
International System (SI) Units). degrees F, the Charpy curves show that Class 1 heavy-wall, large-diameter
Tc is the temperature above which the most of the materials will not reach piping composed of ferritic, austenitic
elastic plastic fracture mechanics their respective upper-shelf energy stainless steel, and nickel based alloy
(EPFM) method must be applied. levels. The NRC staff’s condition is materials in pressurized water reactors

VerDate Sep<11>2014 14:56 Jan 16, 2018 Jkt 244001 PO 00000 Frm 00010 Fmt 4700 Sfmt 4700 E:\FR\FM\17JAR1.SGM 17JAR1
2340 Federal Register / Vol. 83, No. 11 / Wednesday, January 17, 2018 / Rules and Regulations

either a corrosion rate of two times the provided by Code Case N–795, would be nuclear power plant design provides for
actual measured corrosion rate at the performed at slightly reduced pressures multiple barriers to the accidental
reinforcement pad installation location and normal plant conditions, which the release of fission products from the
or four times the estimated maximum NRC finds will constitute an adequate reactor.
corrosion rate for the system. To ensure leak examination and would reduce the 2. Hydrotesting must be done
that a conservative corrosion rate is risk associated with abnormal plant essentially water solid (i.e., free of
used to provide sufficient margin, the conditions and alignments. pockets of air, steam or other gases) so
NRC considered adding a second However, the NRC has had a long- that stored energy in the reactor coolant
condition that requires that the design standing prohibition against the is minimized during a hydrotest or
of the pressure pad use the higher of the production of heat through the use of a leaktest.
two corrosion rates calculated, based on critical reactor core to raise the 3. The elevated reactor coolant
the same degradation mechanism as the temperature of the reactor coolant and temperatures, associated with critical
degraded location. However, as a result pressurize the RCPB. A letter dated operation, result in a severely
of a public comment, the NRC February 2, 1990, from James M. Taylor, uncomfortable and difficult working
reconsidered and determined that using Executive Director for Operations, NRC, environment in plant spaces where the
a corrosion rate of either two times the to Messrs. Nicholas S. Reynolds and system leakage inspections must be
actual measured corrosion rate in that Daniel F. Stenger, Nuclear Utility conducted. The greatly increased stored
location, or four times the estimated Backfitting and Reform Group (ADAMS energy in the reactor coolant, when the
maximum corrosion rate for the system, Accession No. ML14273A002), reactor is critical, increases the hazard
already provides a sufficiently established the NRC position with to personnel and equipment in the event
conservative estimate of the corrosion respect to use of a critical reactor core of a leak. As a result, the ability for
rate; therefore, a condition is not to raise the temperature of the reactor plant workers to perform a
needed. coolant and pressurize the RCPB. In comprehensive and careful inspection
summary, the NRC’s position is that becomes greatly diminished.
Code Case N–795 [Supplement 3, 2010 testing under these conditions involves However, the NRC staff has
Edition] serious impediments to careful and determined that pressure testing with
Type: New. complete inspections, and therefore, the core critical is acceptable, if
Title: Alternative Requirements for inherent uncertainty with regard to performed after repairs of a limited
BWR Class 1 System Leakage Test assuring the integrity of the RCPB. scope, where only a few locations or a
Pressure Following Repair/Replacement Further, the practice is not consistent limited area needs to be examined, and
Activities, Section XI, Division 1. with basic defense-in-depth safety when ASME Code Section XI, Table
The NRC is approving Code Case N– principles. IWB–2500–1, Category B–P (the
795 with two conditions. The first The NRC’s position established in pressure test required once per cycle of
condition addresses a prohibition 1990, was reaffirmed in Information the entire RCPB), has been recently
against the production of heat through Notice No. 98–13, ‘‘Post-Refueling performed, thus verifying the integrity
the use of a critical reactor core to raise Outage Reactor Pressure Vessel Leakage of the overall RCPB. The NRC also notes
the temperature of the reactor coolant Testing Before Core Criticality,’’ dated that Code Case N–795 does not allow for
and pressurize the reactor coolant April 20, 1998. The Information Notice the use of the alternative test pressure
pressure boundary (RCPB) (sometimes was issued in response to a licensee that following repairs/replacements on the
referred to as nuclear heat). The second had conducted an ASME BPV Code, RPV, therefore it does not violate 10
condition addresses the duration of the Section XI, leakage test of the reactor CFR part 50, Appendix G. The NRC
hold time when testing non-insulated pressure vessel and subsequently determined that the risk associated with
components to allow potential leakage discovered that it had violated 10 CFR nuclear heat at low power is comparable
to manifest itself during the part 50, appendix G, IV.A.2.d. This with the risk to the plant, when the test
performance of system leakage tests. regulation states that pressure tests and is performed without nuclear heat (with
Code Case N–795 was intended to leak tests of the reactor vessel that are the core subcritical) during mid-cycle
address concerns that performing the required by Section XI of the ASME outages, when decay heat must be
ASME-required pressure test for boiling Code must be completed before the core managed. Performing the pressure test
water reactors (BWRs) under shutdown is critical. The Information Notice under shutdown conditions at full
conditions, (1) places the unit in a references NRC Inspection Report 50– operating pressure without nuclear heat
position of significantly reduced 254/97–27 (ADAMS Accession No. requires securing certain key pressure
margin, approaching the fracture ML15216A276), which documents that control, heat removal, and safety
toughness limits defined in the licensee personnel performing VT–2 systems. Under such conditions, it is
Technical Specification examinations of the drywell at one BWR more difficult to control temperature
Pressure-Temperature (P–T) curves, and plant covered 50 examination areas in and pressure, when there is significant
(2) requires abnormal plant conditions/ 12 minutes, calling into question the decay heat production, such as after a
alignments, incurring additional risks adequacy of the VT–2 examinations. mid-cycle outage, which may reduce the
and delays, while providing little added The bases for the NRC’s historical margin available to prevent exceeding
benefit beyond tests, which could be prohibition of pressure testing with the the plant pressure-temperature limits.
performed at slightly reduced pressures core critical can be summarized as The scope of repairs should be
under normal plant conditions. follows: relatively small, when the pressure test
However, due to restrictions imposed by 1. Nuclear operation of a plant should is conducted using nuclear heat, in
the pressure control systems, most not commence before completion of order to minimize the personnel safety
ethrower on DSK3G9T082PROD with RULES

BWRs cannot obtain reactor pressure system hydrostatic and leakage testing risk and to avoid rushed examinations.
corresponding to 100 percent rated to verify the basic integrity of the RCPB, Code Case N–795 does not place any
power during normal startup operations a principal defense-in-depth barrier to restrictions on the size or scope of the
at low power levels that would be the accidental release of fission repairs for which the alternative may be
conducive to performing examinations products. In accordance with the used, other than the alternative test
for leakage. The alternative test, defense-in-depth safety precept, the pressure may not be used to satisfy

VerDate Sep<11>2014 14:56 Jan 16, 2018 Jkt 244001 PO 00000 Frm 00012 Fmt 4700 Sfmt 4700 E:\FR\FM\17JAR1.SGM 17JAR1
Federal Register / Vol. 83, No. 11 / Wednesday, January 17, 2018 / Rules and Regulations 2341

pressure test requirements following it is appropriate to conservatively associated weldments have not yet been
repair/replacement activities on the specify a longer hold time of 1 hour for developed by the industry. To ensure
reactor vessel. It is impractical to non-insulated components. Therefore, that effective and reliable examinations
specify a particular number of welded the final rule retains the one hour hold are performed, the NRC is adopting the
or mechanical repairs that would time for non-insulated components. following four conditions on the Code
constitute a ‘‘limited scope.’’ However, Case.
Code Case N–799 [Supplement 4, 2010
if the plant is still in a refueling outage The first condition addresses the gap
Edition]
and has already performed the ASME between the probe and component
Section XI Category B–P pressure test of Type: New. surface. Industry experience shows that
the entire RCPB, it is likely that Title: Dissimilar Metal Welds Joining effective ultrasonic examinations
subsequent repairs would be performed Vessel Nozzles to Components, Section depend, to a great extent, on limiting the
only on an emergent basis, and would XI, Division 1. gap between the probe and component
generally be of a limited scope. The NRC approves Code Case N–799 surface to less than 0.032-inch. The BPV
Additionally, the overall integrity of the with four conditions. Code Case N–799 Code does not have any requirements
RCPB will have been recently confirmed is a new Code Case developed to with respect to surface smoothness and
via the Category B–P test. For mid-cycle provide examination requirements for waviness. It has been demonstrated that
maintenance outages, the first condition the steam generator primary nozzle to reduced coupling and probe lift-off on
allows the use of nuclear heat to pump casing attachment weld for AP–
‘‘rough’’ surfaces have the potential to
perform the test, if the outage duration 1000 plants and dissimilar metal welds
present a scattering effect at an interface
is fourteen (14) days or less. This would joining vessel nozzles to pumps used in
where an acoustic beam impinges, to
tend to limit the scope of repairs, and recent reactor designs (e.g., AP–1000,
redirect and mode convert some energy,
also limit use of the Code Case to Advanced BWR). Nuclear power plant
which when returned to the probe can
outages when decay heat was a pump casings are typically
be the source of spurious signals, or
significant problem. Therefore, the first manufactured from cast austenitic
cause flaws to be mis-characterized or
condition on Code Case N–795 states: stainless steel (CASS) materials. The
missed altogether. Accordingly, the first
NRC is approving the Code Case with
‘‘The use of nuclear heat to conduct the BWR condition requires that the scanning
conditions to address the shortcomings
Class 1 system leakage test is prohibited (i.e., surfaces have a gap less than 0.032-inch
the reactor must be in a non-critical state), in the Code Case with respect to
beneath the ultrasonic testing probe.
except during refueling outages in which the requirements for ultrasonic
Gaps greater than 0.032-inch must be
ASME Section XI Category B–P pressure test examination.
The CASS is an anisotropic and considered to be unexamined, unless it
has already been performed, or at the end of
mid-cycle maintenance outages fourteen (14) inhomogeneous material. The can be demonstrated, on representative
days or less in duration.’’ manufacturing process can result in mockups, that a Section XI, Appendix
varied and mixed structures. The large VIII, Supplement 10, demonstration can
With respect to the second condition
size of the anisotropic grains affects the be passed.
and adequate pressure test hold time, The second condition (No. 2a in DG–
the technical analysis supporting Code propagation of ultrasound by causing
severe attenuation, changes in velocity, 1296) is that the examination
Case N–795 indicates that the lower test
and scattering of ultrasonic energy. requirements of Section XI, Mandatory
pressure provides more than 90 percent
Refraction and reflection of the sound Appendix I, paragraph I–3200(c) must
of the flow, which would result from the
beam occurs at the grain boundaries, be applied. Code Case N–799 does not
pressure corresponding to 100 percent
which can result in specific volumes of contain specific requirements regarding
power. However, a reduced pressure
material not being examined, or defects examination techniques. Paragraph I–
means a lower leakage rate, so
being missed or mischaracterized. The 3200(c) contains specific requirements
additional time is required in order for
grain structure of the associated that can be applied.
there to be sufficient leakage to be
weldments also impacts the The third condition (No. 2c in DG–
observed by inspection personnel.
effectiveness and reliability of the 1296) is that ultrasonic depth and sizing
Section XI, paragraph IWA–5213, ‘‘Test
examinations. Accordingly, it is qualifications for CASS components
Condition Holding Time,’’ does not
require a holding time for Class 1 paramount that robust examination must use the ASME BPV Code
components, once test pressure is techniques be used. requirements in Section XI, Appendix
obtained. To account for the reduced Research has been conducted by VIII, Supplement 10. Supplement 10
pressure, Code Case N–795 would several domestic and international contains qualification requirements for
require a 15-minute hold time for non- organizations attempting to address the dissimilar metal welds, and the use of
insulated components. The NRC has shortcomings associated with the use of these requirements will ensure that
determined that 15 minutes does not conventional methods for the inspection robust techniques are applied.
allow for an adequate examination, of CASS materials. The results of a The fourth condition (No. 2e in DG–
because it is not possible to predict the study at Pacific Northwest National 1296) is that cracks that are detected but
entire range of scenarios or types of Laboratory (PNNL) were published in cannot be depth-sized with
defects that could result in leakage. NUREG/CR–6933, ‘‘Assessment of Crack performance-based procedures,
While some types of defects could result Detection in Heavy-Walled Cast equipment, and personnel qualifications
in immediate leakage, such as an Stainless Steel Piping Welds Using consistent with ASME Code Section XI,
improperly torqued bolted connection; Advanced Low-Frequency Ultrasonic Appendix VIII, shall be repaired or
other types of defects, such as weld Methods’’ (ADAMS Accession No. removed.
ethrower on DSK3G9T082PROD with RULES

defects or tight cracks could represent a ML071020409). The study demonstrated OM Code Cases (RG 1.192)
more torturous path for leakage and may that additional measures were required
result in delayed leakage. The staff Code Case OMN–1, Revision 1 [2012
to reliably detect and characterize flaws
determined that, due to the uncertainty Edition]
in CASS materials and their associated
in the time required for leakage to occur weldments. Type: Revised.
to an extent, it would be readily Performance demonstration Title: Alternative Rules for Preservice
detectable by visual examination, hence, requirements for CASS components and and Inservice Testing of Active Electric

VerDate Sep<11>2014 14:56 Jan 16, 2018 Jkt 244001 PO 00000 Frm 00013 Fmt 4700 Sfmt 4700 E:\FR\FM\17JAR1.SGM 17JAR1
2342 Federal Register / Vol. 83, No. 11 / Wednesday, January 17, 2018 / Rules and Regulations

Motor-Operated Valve Assemblies in The conditions on Code Case OMN– by using a factor of 1.10 times the flow
Light-Water Reactor Power Plants. 12 [2012 Edition] are identical to the reference value (Qr) or the differential or
The conditions on Code Case OMN– conditions on OMN–12 [2004 Edition] discharge pressure reference value (DPr
1, Revision 1 [2012 Edition] are that were approved by the NRC in or Pr), as applicable to the pump type.
identical to the conditions on OMN–1 Revision 1 of RG 1.192 in October 2014. The limits for the biennial
[2006 Addenda] that were approved by The reasons for imposing these comprehensive pump test are obtained
the NRC in Revision 1 of RG 1.192 in conditions are not resolved by Code by using the factor of 1.03 times Qr or
October 2014. The reasons for imposing Case OMN–12 [2012 Edition] and, DPr (or Pr), as applicable to the pump
these conditions are not resolved by therefore, these conditions have been type, providing more restrictive test
Code Case OMN–1, Revision 1 [2012 retained in Revision 2 of RG 1.192. ranges and higher quality data.
Edition] and, therefore, these conditions Code Case OMN–18, 2012 Edition,
have been retained in Revision 2 of RG Code Case OMN–16, Revision 1 [2012 would remove the Code requirement to
1.192. Edition] perform a biennial comprehensive
Type: Revised. pump test, where the quarterly Group A
Code Case OMN–3 [2012 Edition] Title: Use of a Pump Curve for pump test is performed within ±20
Type: Reaffirmed. Testing. percent of the pump design flow rate,
Title: Requirements for Safety Code Case OMN–16, 2006 Addenda, with instruments having the ability to
Significance Categorization of was approved by the NRC in Regulatory obtain the accuracies required for the
Components Using Risk Insights for Guide 1.192, Revision 1. With respect to comprehensive pump test. The NRC
Inservice Testing of LWR Power Plants. Code Case OMN–16, Revision 1, 2012 finds the performance of a quarterly
The conditions on Code Case OMN– Edition, there was an editorial error in Group A pump test, at flow within ±20
3 [2012 Edition] are identical to the the publishing of this Code Case in that percent of the pump design flow rate,
conditions on OMN–3 [2004 Edition] Figure 1 from the original Code Case will be sufficient to detect mechanical
that were approved by the NRC in (i.e., Rev. 0, 2006 Addenda) was and hydraulic degradation of the tested
Revision 1 of RG 1.192 in October 2014. omitted. Accordingly, the NRC approves pump. The NRC finds that this will
The reasons for imposing these OMN–16, Revision 1, with a condition satisfy the intent of the biennial
conditions are not resolved by Code requiring that Figure 1 from the original comprehensive pump test, with the
Case OMN–3 [2012 Edition] and, Code Case be used when implementing exception that the test acceptable ranges
therefore, these conditions have been OMN–16, Revision 1. and required action ranges are less
retained in Revision 2 of RG 1.192. precise than required for the
Code Case OMN–18 [2012 Edition]
Code Case OMN–4 [2012 Edition] comprehensive test. Therefore, the NRC
Type: Reaffirmed. approves Code Case OMN–18, 2012
Type: Reaffirmed. Title: Alternate Testing Requirements
Title: Requirements for Risk Insights Edition, with a condition to specify the
for Pumps Tested Quarterly Within use of a factor of 1.06 for the Group A
for Inservice Testing of Check Valves at ±20% of Design Flow.
LWR Power Plants. test parameters, to be consistent with
The ASME OM Code defines Group A the test ranges for the comprehensive
The conditions on Code Case OMN– pumps as those pumps that are operated
4 [2012 Edition] are identical to the test. The NRC concludes that the factor
continuously or routinely during normal of 1.06 will provide a reasonable test
conditions on OMN–4 [2004 Edition] operation, cold shutdown, or refueling
that were approved by the NRC in range, when applying Code Case OMN–
operations. The OM Code specifies that 18 to Group A pumps tested quarterly,
Revision 1 of RG 1.192 in October 2014. each Group A pump undergoes a Group
The reasons for imposing these within ±20 percent of the pump design
A test quarterly and a comprehensive flow rate. The NRC finds that the
conditions are not resolved by Code test biennially. The OM Code requires
Case OMN–4 [2012 Edition] and, quarterly Group A test for pumps within
that the reference value for a ±20 percent of the pump design flow
therefore, these conditions have been comprehensive test to be within 20
retained in Revision 2 of RG 1.192. rate, combined with the provisions in
percent of pump design flow, while the the Code Case OMN–18 for the pump
Code Case OMN–9 [2012 Edition] reference value for a Group A test needs instrumentation and the conditions in
Type: Reaffirmed. to be within 20 percent of the pump RG 1.192 for the test ranges, will
Title: Use of a Pump Curve for design flow, if practicable. The biennial provide reasonable assurance of the
Testing. comprehensive test was developed (first operational readiness of these pumps, as
The conditions on Code Case OMN– appeared in the 1995 Edition of the OM an acceptable alternative to the
9 [2012 Edition] are identical to the Code) because pump performance comprehensive pump test provisions in
conditions on OMN–9 [2004 Edition] concerns demonstrated that more the ASME OM Code.
that were approved by the NRC in stringent periodic testing was needed at
Revision 1 of RG 1.192 in October 2014. a flow rate within a more reasonable Code Case OMN–19 [2012 Edition]
The reasons for imposing these range of the pump design flow rate, than Type: Reaffirmed.
conditions are not resolved by Code typically performed during the pump Title: Alternative Upper Limit for the
Case OMN–9 [2012 Edition] and, IST in the past. Comprehensive Pump Test.
therefore, these conditions have been Currently, when performing either the A requirement for a periodic pump
retained in Revision 2 of RG 1.192. quarterly Group A test or the biennial verification test was added in
comprehensive pump test, licensees Mandatory Appendix V, ‘‘Pump
Code Case OMN–12 [2012 Edition] must comply with certain limits for the Periodic Verification Test Program,’’ to
flow Acceptable Range, the flow the 2012 Edition of the OM Code. The
ethrower on DSK3G9T082PROD with RULES

Type: Reaffirmed.
Title: Alternative Requirements for Required Action Range, the differential mandatory appendix is based on the
Inservice Testing Using Risk Insights for pressure (or discharge pressure) determination by the ASME that a pump
Pneumatically and Hydraulically Acceptable Range, and the differential periodic verification test is needed to
Operated Valve Assemblies in Light- pressure (or discharge pressure) confirm that a pump can meet the
Water Reactor Power Plants (OM-Code Required Action Range. The limits for required (differential or discharge)
1998, Subsection ISTC). the quarterly Group A test are obtained pressure as applicable, at its highest

VerDate Sep<11>2014 14:56 Jan 16, 2018 Jkt 244001 PO 00000 Frm 00014 Fmt 4700 Sfmt 4700 E:\FR\FM\17JAR1.SGM 17JAR1
2344 Federal Register / Vol. 83, No. 11 / Wednesday, January 17, 2018 / Rules and Regulations

condition be revised to state ‘‘. . . is to Code Case N–638–8. However, Code previous version. An exception to this
be performed in accordance with IWA– Case N–638–6 does not address provision would be the inclusion of a
4200 of the code of record for the proposed Condition (1) and this version limitation or condition on the use of the
current ISI Program.’’ [ASME 5–3] of the Code Case will be available for Code Case that is necessary, for
NRC Response: The NRC agrees, in use by licensees who will not adopt the example, to enhance safety.’’ Perhaps
part, with this comment. The NRC staff 2013 Edition of Section XI for several this could be supplemented with
has adopted the 2008 Addenda with no years. Therefore, the NRC determined another sentence such as, ‘‘In this case,
conditions on IWA–4200. However, the that it is appropriate to include the condition will be entered for the
staff does not agree that the proposed proposed Condition (1) in RG 1.147, superseded Code Case under Table 5.’’
condition/note in Regulatory Guide Revision 18. [EPRI 2–4, Exelon 7–4]
1.147 should be revised to state ‘‘. . . is Regarding proposed Condition (2),
to be performed in accordance with Paragraph 1(b)(1) of Code Case N–638– NRC Response: The NRC agrees with
IWA–4200 of the code of record for the 6 contains changes from the previous this comment. The condition shown in
current ISI program’’, because there may version of the Code Case, which allows Table 5 of DG–1295 for Code Case N–
be licensees whose code of record is through-wall circumferential welds and 666 was in error.
prior to 2008 and such a condition is includes additional requirements when The condition on Code Case N–666 in
not necessary because licensees would performing repairs that utilize through- Table 5 from the final RG 1.147,
be required to follow IWA–4200 in their wall circumferential welds. At the time Revision 18 has been removed.
code of record, if they were to adopt this that this revision of the Code Case was No change was made to the final rule
Code Case. As a result, because use of approved by the ASME, the staff had as a result of this comment.
the repair method described in this concerns related to through-wall repairs.
Code Case (N–576–2) requires the NRC’s Subsequently, the NRC resolved its Comment: Condition 1—The
review and approval prior to concerns. Therefore, the NRC construction code may not always
implementation and licensees will be determined that proposed Condition (2) require a surface examination
required to follow IWA–4200 in their is unnecessary. (depending on the construction code) on
code of record, the NRC modified the The NRC has removed proposed socket welds. This condition is
‘‘note’’ on this Code Case to eliminate Condition (2) on Code Case N–638–6 appropriate. However, the words ‘‘and
the portion of the ‘‘note’’ regarding from the final RG 1.147, Revision 18. seal weld’’ in the first sentence should
reconciliation. The revised ‘‘note’’ now No change was made to the final rule be removed from the condition because
reads: as a result of this comment. it is inappropriate to require surface
‘‘Note: Steam generator tube repair examination of non-structural seal
Code Cases N–666 and N–666–1
methods require prior NRC approval welds whose only function is to seal a
through the Technical Specifications. Comment: A new condition has been leak. The ASME recommends revising
This Code Case does not address certain added to N–666, which is listed as a this condition to remove the words ‘‘and
aspects of this repair, e.g., the Superseded Code Case: A surface seal weld’’ in the first sentence.
qualification of the inspection and (magnetic particle or liquid penetrant) Condition 2—This condition should be
plugging criteria necessary for staff examination must be performed after removed as 5(a)(1) already required a
approval of the repair method.’’ installing the seal weld and weld Visual VT–1 examination of completed
overlay on Class 1 and 2 piping socket weld overlays irrespective of the class of
Code Case N–638–6 welds. The fabrication defects, if the joint. This condition is redundant
Comment: Condition 1 was detected, must be dispositioned using and only causes confusion. ASME
incorporated into IWA–4673(a)(2) of the the surface examination acceptance recommends removing this proposed
2013 Edition when N–638–6 was criteria of the Construction Code condition. [EPRI 2–1, ASME 5–5]
incorporated into the Code. This identified in the Repair/Replacement
condition has also been incorporated Plan. NRC Response: The NRC agrees with
into N–638–8, which has been As stated in our comment on N–666– this comment. The function of the seal
published in the 2015 Code Case Book. 1, the phrase ‘‘seal weld and’’ should be weld is to seal a leak so that sound
Condition (2) was incorporated into removed from the first sentence. Also, weldment for the overlay can be
IWA–4671(b)(1) of the 2013 Edition the addition of a new condition to a applied. The code case requires a visual
when N–638–6 was incorporated into Code Case that was previously examination of the seal weld, remaining
the Code. Because there were no unconditionally approved in the Reg. socket weld, and adjacent base material
conditions imposed on the use of IWA– Guide, and is now superseded, seems before the weld overlay can be applied,
4673(a)(2) or IWA–4671(b)(1) in the inappropriate. Several plants would which the NRC has determined is the
draft rule, to incorporate by reference likely have this version of the Code Case appropriate examination prior to the
the 2013 Edition of the ASME BPV in their Section XI ‘‘tool box’’ until the application of the weld overlay.
Code, Section XI, ASME recommends end of their current Inspection Interval, Therefore, Condition 1 has been revised
that both of the proposed conditions be and would be apparently (but not to remove ‘‘and seal weld.’’ Regarding
removed and Code Case N–638–6 be obviously) bound by the new condition, Condition 2, the NRC agrees with the
moved to Table 1 of RG 1.147, Revision upon issuance of the new revision to commenter. The code case requires a
18. [ASME 5–4] Regulatory Guide. The third paragraph visual examination of the seal pass and
NRC Response: The NRC agrees, in under Section B. DISCUSSION, in the the completed weld overlay and
part, with this comment. Regarding draft RG, includes the statement ‘‘If a provides appropriate acceptance
proposed Condition (1), the staff agrees Code Case is implemented by a licensee criteria. Therefore, the condition is
ethrower on DSK3G9T082PROD with RULES

that Condition (1) was incorporated into and a later version of the Code Case is redundant and unnecessary. Condition
IWA–4673(a)(2) of the 2013 Edition of incorporated by reference into 10 CFR 2 has been removed from Code Case N–
ASME BPV Code, Section XI, when 50.55a and listed in Tables 1 and 2 666 in Table 2 from the final RG 1.147,
ASME incorporated Code Case N–638– during the licensee’s present 120-month Revision 18.
6 into the Section XI. Proposed ISI program interval, that licensee may No change was made to the final rule
Condition (1) was also addressed in use either the later version or the as a result of this comment.

VerDate Sep<11>2014 14:56 Jan 16, 2018 Jkt 244001 PO 00000 Frm 00016 Fmt 4700 Sfmt 4700 E:\FR\FM\17JAR1.SGM 17JAR1
Federal Register / Vol. 83, No. 11 / Wednesday, January 17, 2018 / Rules and Regulations 2345

Code Case N–711 which restricts the application of this (e.g., the use of ‘‘may’’), it would need
Comment: ASME recommends that material condition to exempt volumetric to be demonstrated that application of
this Code Case N–711 be removed from and visual examination requirements in LEFM approaches to flaw assessment on
RG 1.193, Table 2 and added to Table N–770–1. The NRC is concerned that the upper shelf fracture behavior is
2 of RG 1.147 with appropriate the wording of this exemption may always conservative relative to the more
conditions to address NRC technical allow insufficiently mitigated items to technically correct EPFM approach.
concerns with the use of this case. be exempt from currently required This has not been demonstrated in
visual inspection requirements for either Code Case N–749 or in its
[ASME 5–10]
NRC Response: The NRC disagrees components containing alloy 600/82/ supporting technical basis document.
182 to maintain structural and leak-tight As one example, an approach to using
with this comment. The NRC declines at
integrity. Once again though, it is not LEFM on the upper shelf fracture
this time to adopt the recommended
the intent of the NRC to include these behavior would be to continue to use
changes to the regulatory guides. It
items as conditions or limitations in the the ASME KIc curve. At upper shelf
would not be appropriate to include the
regulatory guide. The current wording temperatures, the KIc curve over-
Code Case in RG 1.147 without first
to redirect the user to the applicable estimates the fracture toughness relative
having sought public comment on the
section of § 50.55a(g)(6)(ii)(E) will to the ductile fracture toughness (i.e.,
adoption of the Code Case. Nonetheless,
remain, because versions of this ASME J0.1 or J–R), which is non-conservative.
the NRC has reviewed the information No change was made to the final rule
Code Case, as well as N–729 and N–770,
provided by ASME and will consider as a result of this comment.
are not alternatives to the Code
approval of the Code Case in future
requirements, but are mandated by Code Case N–754
rulemaking activities.
§ 50.55a as augmented ISI requirements.
No change was made to the final rule Comment: The third condition
For these reasons the NRC disagrees
as a result of this comment. proposed for this Code Case inversely
with the comment.
Code Case N–722–2 No change was made to the final rule paraphrases existing statements in the
as a result of this comment. Code Case, causing confusion to the
Comment: ASME requests that the user as to what the condition actually
NRC identify any technical concerns Code Case N–749 adds to the existing requirements.
with N–722–2 and list these concerns in Comment: Public comment 5–6 raised Further, by paraphrasing the
R.G. 1.193, Table 2. [ASME 5–11] two main points: requirements, essential technical
NRC Response: The NRC disagrees 1. The comment takes issue with the requirements, such as chrome content in
with this comment. The NRC disagrees temperature, Tc, above which the staff the dilution zone, are omitted which we
with the comment because the NRC suggests that EPFM techniques should do not believe is the intent of the
does not provide comments in the be used. The formula for Tc, given in the condition. The Federal Register states
Regulatory Guide 1.193 on ASME Code staff’s condition, differs from that that the reason for this condition is that
Cases, which the NRC mandates for use proposed in Code Case N–749. ‘‘In this instance, the NRC felt the word
as augmented inservice inspection 2. The comment takes issue with the ‘‘may’’ needed to be changed to ‘‘shall’’
programs under § 50.55a(g)(6)(ii). Any part of the staff’s condition stating that in the second sentence in paragraph
conditions that the NRC finds necessary ‘‘Tc is the temperature above which 1.2(f)(2) as a condition for use of this
to require are included under the elastic plastic fracture mechanics Code Case.’’ In the English language,
particular section of § 50.55a(g)(6)(ii)(D), (EPFM) must be applied.’’ Item 4 of the when the term ‘‘may’’ is followed by the
(E) or (F), as applicable. This is to avoid public comment suggests adopting a word ‘‘not’’, the phrase means the same
confusion such that a stakeholder does permissive rather than a perspective as ‘‘shall not.’’ However, if this phrase
not use versions of these ASME Code condition by replacing the word ‘‘must’’ is truly a concern for some, then the
Cases in lieu of the mandated versions with the word ‘‘may’’ in the preceding condition should be written exactly as
of the ASME Code Case in sentence. [ASME 5–6] the Code Case except change the one
§ 50.55a(g)(6)(ii). However, in order to NRC Response: The NRC disagrees word ‘‘may’’ to ‘‘shall.’’ [EPRI 2–2,
be responsive to the stakeholder with this comment. The staff’s ASME 5–7]
comment, the NRC will provide the responses to these points are, as follows: NRC Response: The NRC disagrees
current concerns with the Concerning point 1, the technical with this comment. Condition (3)
implementation of ASME Code Case N– bases for the staff’s proposed equation addresses the following two statements
722–2, as a response to this comment to for Tc are well documented, as in Paragraph 1.2(f)(2) of Code Case N–
be included in the Federal Register discussed previously, and are well 754 that reads: ‘‘. . . The first layer of
notice. supported by data for RPV steels both weld metal deposited may not be
The NRC currently finds ASME Code before and after neutron irradiation. credited toward the required thickness,
Case N–722–2 unacceptable as written This documentation appears in PVP but the presence of this layer shall be
due to the following main issues. First, 2015–45307. Conversely, the Tc considered in the design analysis
the basis for the removal of the Parts equation in the proposed Code Case requirements in 2(b). Alternatively, a
Examined from N–722–1 was found to relates only to the intersection of the first diluted layer may be credited
be in error. According to an ASME Code ASME KIc curve with a fracture toward the required thickness, provided
interpretation, XI–1–13–27, not all items toughness (KIc) value of 220 MPa√m, a the layer and the associated dilution
removed in N–722–2 were covered by value that does not correspond well to zone contain at least 24% Cr
the inspection requirements of ASME any known materials data and, [chromium] . . .’’ The first sentence in
Code Case N–770–1. The ASME Code Paragraph 1.2(f)(2) could be interpreted
ethrower on DSK3G9T082PROD with RULES

moreover, does not account for the
Case N–722 will need to be revised with effects of irradiation embrittlement. The so that the first weld layer could be
a new basis for the removal of Parts NRC staff’s proposal for Tc is thus better credited toward the required thickness
Examined to be considered for approval supported by materials data than is the because the word ‘‘may not’’ does not
by the NRC. Second, Note 11 is not Code Case value. absolutely prohibit such action. In
acceptable. The bases for this concern is Concerning point 2, in order for a addition, the first sentence in the quoted
the same basis as § 50.55a(g)(6)(ii)(F)(2), permissive condition to be acceptable statements does not have restriction on

VerDate Sep<11>2014 14:56 Jan 16, 2018 Jkt 244001 PO 00000 Frm 00017 Fmt 4700 Sfmt 4700 E:\FR\FM\17JAR1.SGM 17JAR1
2346 Federal Register / Vol. 83, No. 11 / Wednesday, January 17, 2018 / Rules and Regulations

the chromium contents for crediting the those samples would be required to evaluated and approved the Code Case
first weld layer toward the required contain actual flaws whereas over many for application at dozens of domestic
thickness. hours of field experience, fewer flaws plants. Those SERs require that the
The second sentence in the above may be encountered. Further, to ensure reinforcing pad be designed to
quote limits the chromium content of at the effectiveness of the laboratory accommodate twice the actual measured
least 24 percent; however, the second practice, the Level II experience time corrosion rate or if unknown, then 4
sentence began with the word would be credited only after the times the maximum experienced in that
‘‘Alternatively.’’ The word individual passed an Appendix VIII, or a similar system at the same plant for
‘‘Alternatively’’ implies that the Supplement 2 performance the same degradation mechanism.
requirement in the second sentence is demonstration for length and depth Corrosion rates are dependent upon
optional, i.e., a licensee may choose to sizing. Since other performance many system variables—one primary
satisfy either the first sentence or the demonstrations are required for factor being the amount and frequency
second sentence, but the licensee does certification for vessels, ferritic piping of fluid flow. To impose the rate that
not need to satisfy both. and bolting, for example, it is may occur on a seldom-used dead-leg of
For example, a licensee deposits a considered reasonable to only require a system to an area of active flow, where
first weld layer that contains less than the Supplement 2 performance the actual corrosion rate has been
24 percent chromium. The licensee demonstration as a threshold for measured is technically inappropriate.
could consider the first layer, as part of crediting the laboratory practice hours. Since the monthly monitoring imposed
the required weld overlay thickness, EPRI will provide reports by Condition (1) was initiated for the
based on the first sentence above (Nondestructive Evaluation: Fast-Track same reason that this condition was
because the first sentence does not NDE Work Force Enhancement, Volume proposed—namely, the potential for an
identify a specific chromium content. 1; 1019119 and Nondestructive unexpected corrosion rate—this
Therefore, it does not restrict the Evaluation: Fast-Track NDE Work Force condition should be removed. [EPRI 2–
consideration of the first layer for the Enhancement, Volume 2, 1021150) to 3, ASME 5–8]
required weld overlay thickness. The the USNRC to support this Code Case NRC Response: The NRC agrees with
second sentence in the above quote does and address the impact of the reduced this comment. The NRC determined that
require the chromium content to be at experience. This case does not reduce the current language in the Code Case,
least 24 percent. However, the licensee the training hours. [ASME 5–12] which requires using a corrosion rate of
could interpret that the second sentence NRC Response: The NRC disagrees either two times the actual measured
does not apply to this case because the with this comment. The ASME BPV corrosion rate in that location, or four
second sentence is an alternate, optional Code replaces field experience with times the estimated maximum corrosion
requirement based on the word training hours without a defined rate for the system, is reasonable and
‘‘Alternatively.’’ technical basis. While the NRC is open provides a conservative estimate of the
The staff finds that Condition (3) does to evidence related to a technical basis corrosion rate. This conservatively
not omit the essential technical for the substitution of laboratory estimated corrosion rate, coupled with
requirements such as the chrome experience as a substitute for hours of proposed Condition (1) that requires
content in the dilution zone. Condition work experience, the impact of the enhanced inservice monitoring,
(3) requires that if the first weld layer substitution of laboratory hours for field provides reasonable assurance that
cannot achieve a chromium content of experience and nuclear power plant should corrosion rates be more
at least 24 percent, it cannot be familiarization is unknown. The two aggressive than originally predicted,
considered as part of the weld overlay documents cited in the comment require there will be sufficient time to initiate
thickness. The staff recognizes that 1,050 hours of hands-on practice with corrective actions prior to excessive
Condition (3) provides the same hundreds of hours of additional leakage or loss of structural integrity.
requirements as in Paragraph 1.2(f)(2). classwork, not only 320 hours of Therefore, the NRC has determined that
However, the purpose of Condition (3) laboratory training. If future work proposed Condition (2) is not necessary.
is to clarify the requirements in showed that 320 hours would be The NRC has removed proposed
Paragraph 1.2(f)(2). sufficient or the Code Case was Condition (2) on Code Case N–789 from
No change was made to the final rule modified to be in line with these the final RG 1.147, Revision 18.
as a result of this comment. documents, the NRC would consider No change was made to the final rule
allowing the use of the Code Case. as a result of this comment.
Code Case N–784 Comment: Paragraph 3.2(i) of Code
No change was made to the final rule
Comment: This Code Case enables as a result of this comment. Case N–789 has a typographic error
personnel to receive credit for where it states ‘‘. . . piping designed to
experience hours for laboratory practice Code Case N–789 NC–2650, ND–3650. . . .’’ NC–2650
beyond the required number of hours of Comment: The NRC Condition [2] should be NC–3650. Code Case N–789–
laboratory training. For Level II does not allow the user to apply the 2 corrected this statement to read ‘‘. . .
certification, the total experience hours actual corrosion rate for the pressure piping designed to NC–3650 or ND–
may be reduced from 800 to 400 if the pad design. This reflects the staff 3650. . . .’’ The use of this Code Case
experience consists of a combination of position that the factors of 2 and 4 do N–789 should be conditioned to require
80 hours of field experience and 320 not provide reasonable assurance that using the corrected language for
hours laboratory practice by scanning actual corrosion rate is bounded. paragraph 3.2(i) in N–789–2.
specimens containing flaws in materials However, the compensatory measures of [Anonymous 3–1, Exelon 7–1]
representative of those in actual power inservice monitoring and the short NRC Response: The NRC agrees with
ethrower on DSK3G9T082PROD with RULES

plant components. The field experience acceptance period of one operating the commenter. Code Case N–789
will likely be in nuclear plants but there cycle verify and provide assurance that Paragraph 3.2(i) contains a
is no requirement for UT examiners to both structural and leak integrity will be typographical error. The code case
obtain their experience in a nuclear maintained during the temporary references NC–2650 and the correct
plant. While the experience credited acceptance period. Condition (2) is reference is NC–3650. NC–2650 does
would be on samples and mockups, contrary to several NRC SERs that have not exist in ASME Code Section III and

VerDate Sep<11>2014 14:56 Jan 16, 2018 Jkt 244001 PO 00000 Frm 00018 Fmt 4700 Sfmt 4700 E:\FR\FM\17JAR1.SGM 17JAR1
Federal Register / Vol. 83, No. 11 / Wednesday, January 17, 2018 / Rules and Regulations 2347

NC–3650 is the correct portion of the securing certain key pressure control, types of defects could result in immediate
Code to use for the design of reinforcing heat removal, and safety systems. Under leakage, such as an improperly torqued
pads. The NRC does not believe that this such conditions, it is more difficult to bolted connection, other types of defects,
typographical error represents a safety such as weld defects or tight cracks could
control temperature and pressure, when
represent a more torturous path for leakage
concern. In order to prevent the delay of there is significant decay heat and may result in delayed leakage. Because
issuance of the final rule by including production, such as after a mid-cycle the visual examination may be conducted
a new condition on the code case, the outage, which may reduce the margin with the core critical, stay times for
NRC will address this issue in a future available to prevent exceeding the plant examiners in containment may be limited;
rulemaking. pressure-temperature limits. therefore, it is desirable that any leakage be
No change was made to the final rule The NRC considers it desirable that readily detectable. The staff determined that,
as a result of this comment. the scope of repairs be relatively small due to the uncertainty in the time required
when the pressure test is conducted for leakage to occur, to an extent that it
Code Case N–795 would be readily detectable by visual
using nuclear heat, in order to minimize
Comment: The commenters requested examination, it is appropriate to
the personnel safety risk and to avoid
that one or both proposed conditions on conservatively specify a longer hold time of
rushed examinations. The staff 1 hour for non-insulated components.
the use of this Code Case in DG–1296 be considers it impractical to specify a Therefore, no changes are made to Condition
removed: (1) Prohibition of use of particular number of welded or (2) requiring a 1-hour hold time for non-
nuclear heat to perform the leakage test; mechanical repairs that would insulated components.
and (2) Hold time for noninsulated constitute a ‘‘limited scope.’’ However,
components must be 1 hour versus 15 No change was made to the final rule
if the plant is still in a refueling outage
minutes required by Code Case N–795. as a result of this comment.
and has already performed the ASME
[Southern 4–1, ASME 5–9, and Exelon Section XI Category B–P pressure test of Code Case N–799
7–2] the entire RCPB, it is likely that
NRC Response: The NRC agrees, in Comment: This is a Code Case to
subsequent repairs would be performed define the examination volume/area
part, with this comment. As discussed
only on an emergent basis and would where older Section XI codes (up
in detail in the proposed rule in 81 FR
generally be of a limited scope. through 2010 Edition) do not recognize
10780, dated March 2, 2016, the
Additionally, the overall integrity of the the defined configuration. The
historical prohibition of the use of
RCPB will have been recently confirmed conditions proposed in the Code Case
nuclear heat for pressure testing is based
via the Category B–P test. For mid-cycle are not included in the proposed rule to
on concerns about the quality of the
maintenance outages, the staff proposes accept the 2013 Edition of Section XI
VT–2 examinations performed with the
to modify the condition to incorporate and the Code Case configuration is
core critical, due to the high
a limit on the outage duration of defined in the 2013 Code Edition.
temperatures in containment, which
limit stay times for inspectors, and also fourteen (14) days. This would tend to Commenters believe that this results in
concerns about personnel safety. limit the scope of repairs, and also limit inconsistent requirements for plants
However, the commenters emphasized use of the Code Case to outages when using older Code versions versus newer
that Code Case N–795 is only intended decay heat was a significant problem. Code versions. The examination
for use in the case of limited scope Therefore, the first condition on Code conditions proposed for this Code Case
repairs, such as the replacement of a Case N–795 in Table 2 of DG–1296, use are not appropriate for a volume of
main steam relief valve pilot valve which currently reads: interest Code Case. If the NRC considers
(involving a single mechanical joint) 1. The use of nuclear heat to conduct the the conditions appropriate, commenters
when the relief valve is found to be BWR Class 1 system leakage test is prohibited believe that they should be included in
leaking during startup. Code Case N– (i.e., the reactor must be in a non-critical a revision to 10 CFR 50.55a to assure
state). consistent application, regardless of
795 states that the alternative test
a. This condition also applies to pressure
pressure may not be used to satisfy the testing of reactor coolant pressure boundary
Code year and Addenda being applied.
requirements of Table IWB–2500–1, components repaired or replaced in Specifically Conditions (3) and (5)
Category B–P (the pressure test required accordance with Section XI, IWA–4000. should be removed from the Code Case.
once per cycle of the entire reactor is modified to read: [Southern 4–2, Southern 4–3, and
coolant pressure boundary). Code Case 1. The use of nuclear heat to conduct the Exelon 7–3]
N–795 does not place any restrictions BWR Class 1 system leakage test is prohibited NRC Response: The NRC agrees, in
on the size or scope of the repairs for (i.e., the reactor must be in a non-critical part, with this comment.
which the alternative may be used, state), except during refueling outages in Regarding the removal of proposed
other than the alternative test pressure which the ASME Section XI Category B–P Condition (3) from N–799, the NRC
may not be used to satisfy pressure test pressure test has already been performed, or disagrees with the comment. The NRC
requirements, following repair/ at the end of mid-cycle maintenance outages doesn’t find that the examination of the
fourteen (14) days or less in duration. inner 1⁄3 of the component-to-
replacement activities on the reactor
With respect to the comment on the second
vessel. condition, the NRC disagrees with this
component weld depicted in Figure 1 of
However, upon review of the public comment. A one hour hold time is not Code Case N–799 provides reasonable
comments, the staff has determined that unreasonable for non-insulated components. assurance that the integrity of the
the risk associated with performing the Inspectors do not need to be in containment component-to-component welds will be
pressure test with nuclear heat at low during the hold time. Comment 5–9 (ASME) maintained throughout the operating
power is comparable with the risk to the discussed the technical basis for Code Case life of the plant. Code Case N–799 was
plant, when the test is performed N–795, which stated that pressure testing at written to support new plant
ethrower on DSK3G9T082PROD with RULES

without nuclear heat (with the core 87 percent of full operating pressure would construction to provide examination
only result in a 7 percent reduction in flow,
subcritical) during mid-cycle outages while the hold time is being increased by 50
requirements for a weld configuration,
when decay heat must be managed. percent from 10 minutes to 15 minutes. which did not exist in Section XI (i.e.,
Performing the pressure test under However, it is not possible to predict the component-to-component welds).
shutdown conditions at full operating entire range of scenarios or types of defects Specifically, the examination
pressure without nuclear heat requires that could result in leakage. While some requirements described in Code Case N–

VerDate Sep<11>2014 14:56 Jan 16, 2018 Jkt 244001 PO 00000 Frm 00019 Fmt 4700 Sfmt 4700 E:\FR\FM\17JAR1.SGM 17JAR1
2348 Federal Register / Vol. 83, No. 11 / Wednesday, January 17, 2018 / Rules and Regulations

799 would apply to the steam generator subcritical crack growth, the effects of the proposed conditions are not
nozzle-to-reactor coolant pump casing these additional operating loads and appropriate for a volume of interest
(SG-to-RCP) weld in the AP1000 design stresses are indeterminate. Absent either Code Case. The NRC is planning to
and the reactor vessel nozzle-to- of the above, the staff finds that it is include this topic in a future
recirculation pump weld in the inappropriate to limit the examination rulemaking.
Advanced Boiling Water Reactor volume to the inner 1⁄3 of the weld as
(ABWR). The following discussion will Code Case N–806
typical of a piping weld at this time.
focus on the AP1000 design, but the When the examination volume that can Comment: ASME stated that it has
staff’s overall concern is also applicable be qualified by performance taken action to address some of these
to the reactor vessel-to-reactor coolant demonstration is less than 100 percent concerns and has published Code Case
pump connection for the ABWR design. of the weld volume, a licensee should N–806–1, providing additional
The AP1000 design is unique in that include an ultrasonic examination to requirements for determining wall
a reactor coolant pump is welded examine the qualified volume and thickness loss rates. The ASME
directly to each of the two outlet nozzles perform a flaw evaluation of the largest recommends that the NRC consider
on the steam generator channel head. hypothetical crack that could exist in developing conditions on the use of this
This SG-to-RCP weld is a dissimilar the volume not qualified for ultrasonic case that would enable the endorsement
metal (low alloy steel to cast austenitic examination. No change was made to of the case in Table 2 of RG 1.147.
stainless steel with Alloy 52/152 weld the rule as a result of this comment. [ASME 5–13]
metal) circumferential butt weld with a The NRC agrees that performing the NRC Response: The NRC disagrees
double sided weld joint configuration, examination in accordance with Section with this comment. The NRC recognizes
similar to that of a reactor vessel shell XI, Appendix VIII, Supplement 10, for that ASME has addressed the NRC’s
weld. Also, this unique component-to- detection and sizing would eliminate concerns regarding the derivation of the
component weld is part of the reactor the need for the requirement to perform corrosion rate in predicting metal loss in
coolant pressure boundary and is, a flaw evaluation, based on the largest piping and has incorporated the
therefore, subject to the examination hypothetical flaw in the unqualified corrosion rate derivation in the
requirements of ASME Section XI, examination volume. However, the NRC published Code Case N–806–1.
Subsection IWB. determined a full volume examination However, the current rulemaking is for
ASME Section XI, IWB–2500 requires of the entire weld and heat affected zone Code Case N–806, which does not
a full volume examination of all is required to provide reasonable contain sufficient information regarding
component welds, except those welds assurance of structural integrity of the the corrosion rate. The ASME suggested
found in piping and those found in component-to component welds that the NRC develop conditions on the
nozzles welded to piping. However, for addressed by Code Case N–799. The use of the Code Case such that the NRC
the component-to-component welds in NRC also determined that requiring the could approve the Code Case for RG
question, Code Case N–799 only examination procedures to be qualified 1.147. The NRC has determined that
requires a licensee to perform a in accordance with Section XI, approval of Code Case N–806 with
volumetric examination of the inner 1⁄3 Appendix VIII, Supplement 10, would conditions would require too many
of the weld and a surface examination eliminate the need for several of the conditions to address several open
of the outer diameter. The staff notes other conditions that were proposed for issues regarding the relationship to the
that the requirements of Code Case N– N–799. Therefore, the final regulatory derivation of the corrosion rate, which
799 are identical to those in ASME guide was modified to specify only four still need to be resolved. Therefore, the
Section XI, Table IWB–2500–1, NRC cannot approve Code Case N–806
conditions for Code Case N–799, as
Examination Category B–F for welds in this rulemaking.
follows:
between vessel nozzles larger than NPS No change was made to the final rule
4 and piping. As such, the staff does not (i) Ultrasonic examination procedures,
equipment, and personnel shall be qualified as a result of this comment.
believe that examination requirements
by performance demonstration in accordance Code Case N–813
proposed in Code Case N–799 are with Section XI, Appendix VIII, Supplement
appropriate for the component-to- 10. When applying the examination Comment: This Code Case should be
component welds because the service requirements of Figure IWB–2500–8, the removed from Table 2 of Regulatory
conditions of the aforementioned welds examination volume shall be extended to Guide 1.193 and added to Table 1 of
are significantly different from those include 100 percent of the weld. Regulatory Guide 1.147 because of the
that would be experienced by a (ii) Examination requirements of Section following reasons.
traditional vessel nozzle-to-piping/safe XI, Mandatory Appendix I, paragraph I–
end butt weld. Specifically, in addition 3200(c) must be applied. 1. The requirements of Code Case N–813
(iii) Ultrasonic depth and sizing are identical to changes made in the 2013
to the operating environment (RCS
qualifications for cast austenitic stainless Edition of Section XI, which are being
pressure, temperature, and exposure to steel components must follow Appendix VIII, considered under a separate draft 10 CFR
coolant) and loads expected on a Supplement 10, using representative cast 50.55a rule. The NRC has not proposed any
traditional nozzle-to-safe end weld, each austenitic stainless steel mockups containing conditions on these requirements in the 2013
SG-to-RCP weld will support the full representative cracks and be independent of Edition. It is inappropriate for the NRC to
weight of a reactor coolant pump with other Supplement 10 qualifications. impose conditions on the same requirements
no other vertical or lateral supports. The (iv) Cracks detected and not depth sized to in Case N–813 as the requirements in the
SG-to-RCP welds will also be subject to Appendix VIII type performance-based 2013 Edition.
pump rotational forces and vibration procedures, equipment, and personnel 2. This Case permits acceptance of
qualifications shall be repaired or removed. subsurface flaws detected during preservice
ethrower on DSK3G9T082PROD with RULES

loads from both the steam generator and
examination using the same criteria
the reactor coolant pump during service. The NRC agrees with the examination
applicable to flaws detected during inservice
In the absence of operating experience requirement regarding the consistency examination. There is no greater likelihood of
for the weld in question or a bounding between the Code Case and the codes, subsurface flaws detected during preservice
analysis, which demonstrates that a where the Code Case that has been examination to grow unacceptably than there
potential fabrication defect in the outer incorporated should be consistent. The is for the same flaws to grow during inservice
2⁄3 of the weld will not experience NRC disagrees with the statement that examination. Operating experience has

VerDate Sep<11>2014 14:56 Jan 16, 2018 Jkt 244001 PO 00000 Frm 00020 Fmt 4700 Sfmt 4700 E:\FR\FM\17JAR1.SGM 17JAR1
Federal Register / Vol. 83, No. 11 / Wednesday, January 17, 2018 / Rules and Regulations 2349

shown that the propensity for failure is permits the existence of unacceptable examiner to discriminate between these
increased by repairing such flaws, whereas flaws, which do not meet the ASME types of flaws. The revised wording for
leaving them in place has never been shown Code preservice acceptance criteria, in RG 1.193 is:
to be a precursor to failure. Without weld
welds before their deployment. The The NRC has been conducting research at
repair, there is no mechanism expected to
produce unacceptable flaw growth, whereas code case allows these unacceptable Pacific Northwest National Laboratory on the
repair welding itself has been repeatedly flaws to be accepted by analytical examination of austenitic and ferritic welds.
shown to cause flaws to grow to the point of evaluation. The code case places no The work has shown that performing a full
failure. The provisions of this Case, and the limits on such flaws (i.e., a weld could volume ultrasonic examination for
identical provisions in the 2013 Edition, have more than one unacceptable flaw fabrication flaws is significantly different
improve safety. or numerous welds within a piping run from an inservice examination. For example,
3. The technical basis for this Code Case could have flaws that did not meet the examination from two directions is necessary
and accompanying Code revision states that
preservice acceptance criteria), whereas to detect certain circumferentially oriented
the action is being sought to prevent the
the original fleet of nuclear plants had fabrication flaws such as lack of fusion. The
unnecessary excavation and weld repair of
subsurface indications, which can be no unacceptable preservice flaws. The work has also shown that the second leg of
analytically shown to be benign over the staff concludes that it cannot approve a V-path can be applied to examine ferritic
expected service lifetime of a component. Code Case N–813 in this rulemaking. materials on a limited basis but to date the
Based on operating experience, it is known The NRC will continue to evaluate technical basis has not been established to
that weld repairs and their associated stress operating experience relative to this show that these techniques will be effective
fields often serve as points of initiation for type of flaw to further inform decisions on austenitic materials and dissimilar metal
inservice degradation mechanisms (e.g., welds. Another finding is that surface
on possible approval of this code case
intergranular stress corrosion cracking, conditions are critical with respect to
primary water stress corrosion cracking, etc.). in future rulemakings.
detecting and characterizing fabrication
Hence, it is in the best interest of the long No change was made to the final rule
flaws. In summary, the NRC finds that an
term safe operation of components being as a result of this comment. analytical approach for the acceptance of
placed into service to eliminate the need for certain fabrication flaws could be acceptable
Code Case N–818
weld repairs where they are not necessary to if appropriately justified and the scope
correct fabrication problems, which will not Comment: Code Case N–818 should limited to ferritic materials. The NRC finds
challenge the operability of the component be removed from Regulatory Guide that significant research will be required to
over its service lifetime. This can be achieved 1.193 and be allowed for use, as the
by permitting licensees to effectively utilize demonstrate that full-volume ultrasonic
reasons given in Regulatory Guide 1.193 examination for fabrication flaws is
the flaw evaluation rules of IWB–3600 and
to disallow Code Case N–818 have the acceptable for austenitic and dissimilar metal
IWC–3600, which are already accepted for
the analysis of indications due to inservice following issues: (a) The fact that the welds.
degradation. examination will be difficult should not
4. It is important to note that any be a reason to prohibit it as Mandatory Regulatory Guide 1.192, Revision 2
preservice flaw that has been evaluated as Appendix I requires that the (DG–1297)
acceptable is required to receive successive technique(s) to be applied for the Code Case OMN–20
examinations under IWB–2420(b) or IWC– volumetric procedure be demonstrated
2420(c) so if the flaw does grow, it will be on specimens simulating geometric, Comment: Allow the use of Code Case
detected during these examinations. [ASME material and surface conditions to be
5–14] OMN–20 for those plants that
encountered during implementation. (b) implement ASME OM Code 2015
NRC Response: The NRC disagrees The discussion that ultrasound may Edition and earlier editions and
with this comment, in part. The NRC have difficulties discerning between addenda. [Gowin 6–1]
has recognized that the provisions in planar and volumetric flaws is not
Code Case N–813 are identical to NRC Response: The NRC agrees, in
relevant. There is no requirement in the
changes made in the 2013 Edition of the Code Case to characterize the flaw by part, with this comment. Code Case
ASME BPV Code, Section XI. The NRC type (i.e., planar or volumetric). (c) The OMN–20 cannot be implemented with
addressed the contents of the 2013 suggestion that its application should be the 2015 Edition of the ASME OM Code
Edition of the ASME BPV Code, limited to ferritic weldments defeats the because the 2015 Edition has not been
including the Code provisions identical purpose of Code Case N–818. [EPRI 2– incorporated by reference into § 50.55a.
to those allowed in Code Case N–813, in 5, Southern 4–4] Code Case OMN–20 is currently
a separate rulemaking. NRC Response: The NRC disagrees applicable to the 2009 Edition through
The NRC recognizes that operating with this comment, in part. At present, the OMa–2011 Addenda and all earlier
experience has shown that repairing a the NRC has not received any editions and addenda. Licensees who
weld that contains fabrication defects supporting documents from the industry adopt the 2012 Edition of the ASME OM
may cause the defect to grow in the to address the NRC’s concern regarding Code would not be able to use Code
future. On the other hand, permitting a this Code Case, such as a demonstration Case OMN–20, without submitting a
weld that contains a known of the adequacy of a full volume relief request to the NRC for approval.
unacceptable fabrication defect prior to ultrasonic examination for fabrication For this reason, the NRC partially agrees
deployment is not appropriate and is flaws in austenitic welds. Therefore, the with the comment. The NRC believes
contrary to the fundamental engineering wording of the reasons given in RG that Code Case OMN–20 should be
principle of a good design. The 1.193 should not refer to the inspection allowed to be implemented with the
fundamental engineering design is that being difficult for austenitic materials 2012 Edition and earlier editions and
a component should not contain defects and dissimilar metal welds, but should addenda of the ASME OM Code. The RG
before placing it into service. The staff instead refer to there not being an 1.192 was updated to add a condition
ethrower on DSK3G9T082PROD with RULES

has accepted the provision of ASME established technical basis for the use of stating that Code Case OMN–20 is
BPV Code, Section III that permits ultrasound to find fabrication flaws in applicable to the editions and addenda
acceptable flaws (i.e., small insignificant these materials. Additionally, the of the ASME OM Code listed in
flaws) in a weld to exist before discussion of planar vs. volumetric § 50.55a(a)(1)(iv).
deployment. The staff’s objection to flaws will be removed from RG 1.193, as No change was made to the final rule
Code Case N–813 is that the code case the Code Case does not require the as a result of this comment.

VerDate Sep<11>2014 14:56 Jan 16, 2018 Jkt 244001 PO 00000 Frm 00021 Fmt 4700 Sfmt 4700 E:\FR\FM\17JAR1.SGM 17JAR1
2350 Federal Register / Vol. 83, No. 11 / Wednesday, January 17, 2018 / Rules and Regulations

Public Comments on the Proposed Rule Cases that are superseded by ASME or superseded in Table 5 of Regulatory
Comment: The ASME Code is those Code Cases that are listed as Guide 1.147 and in Table 5 of
updated every year. Preparations are superseded in Table 5 of Regulatory Regulatory Guide 1.84. [ASME 5–1 and
underway to publish the 2017 edition. Guide 1.147. ASME 5–15]
ASME recommends revising the ASME provides the following
NRC is working on 2010 Edition. It
second sentence of this paragraph to recommendations:
appears that NRC is not in compliance
clarify that ‘‘The older or superseded i. ASME recommends that the NRC
with National Technology Transfer and
version of the Code Case, if listed in clarify the above concern in the final
Advancement Act of 1995 (NTTAA) by
Table 5, cannot be applied by the rule.
passive non-compliance. Since NRC has ii. ASME recommends that the NRC
licensee or applicant for the first time.’’
many participants in the Code process, review requirements for superseded
[ASME 5–1]
they should be prepared to act as soon NRC Response: The NRC agrees with ASME Section III and OM Code Cases
as final standards votes are counted. this comment. The proposed additional in RG 1.84 and RG 1.192 for similar
[Donavin 1–1] text will add clarity to the information clarification.
NRC Response: The NRC disagrees presented in Table 5. The final RG 1.147 NRC Response: The NRC agrees with
with this comment. The NRC in the introductory paragraph to Table this comment as noted in the response
appreciates the ASME’s efforts to 5, has been revised to include the to Comment 5–1. In addition to that
consider the NRC’s concerns as statement, ‘‘The older or superseded clarifying text being added in the
addressed in conditions to § 50.55a. The version of the Code Case, if listed in introduction to Table 5 in RG 1.147, it
NRC agrees that delays in approving Table 5, cannot be applied by the will also be added to the introduction of
new ASME Code editions and Code licensee or applicant for the first time.’’ Table 5 in RG 1.84. The RG 1.192 does
Cases can be counterproductive with at the end of the explanatory text above not contain a table of superseded Code
respect to implementation of Table 5. Cases, therefore, no change will be made
improvements in ASME Code No change was made to the final rule to the RG 1.192.
requirements. The NRC continues to as a result of this comment. No change was made to the final rule
assess ways to improve the rulemaking Comment: The Code Case [N–711] as a result of this comment.
process to find schedule efficiencies. would permit each licensee to
No change was made to the final rule independently determine when V. Section-by-Section Analysis
as a result of this comment. achievement of a coverage requirement The following paragraphs in § 50.55a,
Comment: Many of the conditions are is impractical, and when Code-required which list the three RGs that are being
historical and are the result of a single coverage is satisfied. As a result, incorporated by reference, are revised as
reviewer’s opinion. An example is the application of the Code Case for similar follows:
rules for the 1994 edition where I configurations at different plants could Paragraphs (a)(3)(i): The reference to
watched an NRC reviewer living in result in potentially significant ‘‘NRC Regulatory Guide 1.84, Revision
Washington, DC telling a PhD from quantitative variations. Furthermore, 36,’’ is amended to remove ‘‘Revision
Tokyo, Japan, that his seismic analysis application of the Code Case is 36’’ and add in its place ‘‘Revision 37.’’
defending the edition was non inconsistent with NRC’s responsibility Paragraphs (a)(3)(ii): The reference to
conservative. If there are legitimate for determining whether examinations ‘‘NRC Regulatory Guide 1.147, Revision
questions, these should be separated are impractical, and eliminates the 17,’’ is amended to remove ‘‘Revision
from the ‘‘not sufficiently conservative’’ NRC’s ability to take exception to a 17’’ and add in its place ‘‘Revision 18.’’
or ‘‘insufficient information’’ licensee’s proposed action and impose Paragraphs (a)(3)(iii): The reference to
justifications. The Commission has set a additional measures where warranted in ‘‘NRC Regulatory Guide 1.192, Revision
precedent in CVR for SECY–15–0106. accordance with 10 CFR 50.55a(g)(6)(i). 1,’’ is amended to remove ‘‘Revision 1’’
ASME has endeavored to address ASME recommends that this case be and add in its place ‘‘Revision 2.’’
conditions with docketed letters and removed from RG 1.193, Table 2 and
Code actions. [Donavin 1–2] Overall Considerations on the Use of
added to Table 2 of RG 1.147 with
NRC Response: The NRC disagrees ASME Code Cases
appropriate conditions to address NRC
with this comment. Although a single technical concerns with the use of this This rulemaking amends § 50.55a to
reviewer may state a contrary position, case. [ASME 5–10] incorporate by reference RG 1.84,
NRC reviews all Code Cases and NRC Response: The NRC agrees with Revision 37, which supersedes Revision
comments with appropriate staff and this comment. However, this is a new 36; RG 1.147, Revision 18, which
management. Code Cases that the NRC proposal and cannot be included in this supersedes Revision 17; and RG 1.192,
finds to be conditionally acceptable are rulemaking because it was not provided Revision 2, which supersedes Revision
also listed in RGs 1.84, 1.147, and 1.192, for public comment. Rather than 1. The following general guidance
which are the subject of this include the action in this rulemaking, applies to the use of the ASME Code
rulemaking, together with the the NRC intends to include it within the Cases approved in the latest versions of
conditions that must be used if the Code scope of the rulemaking that will the RGs that are incorporated by
Case is applied. The NRC determined incorporate by reference the 2015 reference into § 50.55a as part of this
that this rule complies with the NTTAA edition of the ASME BPV Code. rulemaking.
and OMB Circular A–119, despite these No change was made to the final rule The approval of a Code Case in the
conditions. If the NRC did not as a result of this comment. NRC RGs constitutes acceptance of its
conditionally accept ASME Code Cases, Comment: In Section IV, ‘‘Section-by- technical position for applications that
Section Analysis’’ of the Proposed Rule are not precluded by regulatory or other
ethrower on DSK3G9T082PROD with RULES

it would disapprove these Code Cases
entirely. dated March 2, 2016 (Federal Register requirements or by the
No change was made to the final rule Vol. 81, No. 41), ASME believes that it recommendations in these or other RGs.
as a result of this comment. is not clear whether the word The applicant and/or licensee are
Comment: ASME believes that it is ‘‘superseded’’ applies to those Code responsible for ensuring that use of the
not clear whether the word Cases that are superseded by ASME or Code Case does not conflict with
‘‘superseded’’ applies to those Code those Code Cases that are listed as regulatory requirements or licensee

VerDate Sep<11>2014 14:56 Jan 16, 2018 Jkt 244001 PO 00000 Frm 00022 Fmt 4700 Sfmt 4700 E:\FR\FM\17JAR1.SGM 17JAR1
Federal Register / Vol. 83, No. 11 / Wednesday, January 17, 2018 / Rules and Regulations 2351

commitments. The Code Cases listed in version incorporated by reference into of nuclear power plants. The companies
the RGs are acceptable for use within § 50.55a and listed in the RGs. that own these plants do not fall within
the limits specified in the Code Cases. The ASME may annul Code Cases that the scope of the definition of ‘‘small
If the RG states an NRC condition on the are no longer required, are determined entities’’ set forth in the Regulatory
use of a Code Case, then the NRC to be inaccurate or inadequate, or have Flexibility Act or the size standards
condition supplements the Code Case, been incorporated into the BPV or OM established by the NRC (§ 2.810).
and does not supersede any condition(s) Codes. If an applicant or a licensee
applied a Code Case before it was listed VII. Regulatory Analysis
specified in the Code Case, unless
otherwise stated in the NRC condition. as annulled, the applicant or the The NRC has prepared a final
The ASME Code Cases may be revised licensee may continue to use the Code regulatory analysis on this regulation.
for many reasons (e.g., to incorporate Case until the applicant or the licensee The analysis examines the costs and
operational examination and testing updates its construction Code of Record benefits of the alternatives considered
experience and to update material (in the case of an applicant, updates its by the NRC. The total estimated net
requirements based on research results). application) or until the licensee’s 120- benefit of this rule is $4.94 million (7%
On occasion, an inaccuracy in an month ISI or IST update interval discount rate) and $5.68 million (3%
equation is discovered or an expires, after which the continued use discount rate). The regulatory analysis is
examination, as practiced, is found not of the Code Case is prohibited, unless available as indicated in the
to be adequate to detect a newly NRC authorization is given under ‘‘Availability of Documents’’ section of
discovered degradation mechanism. § 50.55a(z). If a Code Case is this document.
Hence, when an applicant or a licensee incorporated by reference into § 50.55a
and later annulled by the ASME because VIII. Backfitting and Issue Finality
initially implements a Code Case,
§ 50.55a requires that the applicant or experience has shown that the design The provisions in this rule allow
the licensee implement the most recent analysis, construction method, licensees and applicants to voluntarily
version of that Code Case, as listed in examination method, or testing method apply NRC-approved Code Cases,
the RGs incorporated by reference. Code is inadequate, the NRC will amend sometimes with NRC-specified
Cases superseded by revision are no § 50.55a and the relevant RG to remove conditions. The approved Code Cases
longer acceptable for new applications, the approval of the annulled Code Case. are listed in the three RGs that are
unless otherwise indicated. Applicants and licensees should not incorporated by reference into § 50.55a.
begin to implement such annulled Code An applicant’s or a licensee’s
Section III of the ASME BPV Code voluntary application of an approved
Cases in advance of the rulemaking.
applies only to new construction (i.e., A Code Case may be revised, for Code Case does not constitute
the edition and addenda to be used in example, to incorporate user experience. backfitting, inasmuch as there is no
the construction of a plant are selected The older or superseded version of the imposition of a new requirement or new
based on the date of the construction Code Case cannot be applied by the position. Similarly, voluntary
permit and are not changed thereafter, licensee or applicant for the first time. application of an approved Code Case
except voluntarily by the applicant or If an applicant or a licensee applied by a 10 CFR part 52 applicant or
the licensee). Hence, if a Section III a Code Case before it was listed as licensee does not represent NRC
Code Case is implemented by an superseded, the applicant or the imposition of a requirement or action
applicant or a licensee and a later licensee may continue to use the Code that is inconsistent with any issue
version of the Code Case is incorporated Case until the applicant or the licensee finality provision in 10 CFR part 52. The
by reference into § 50.55a and listed in updates its Construction Code of Record NRC finds that this rule does not
the RGs, the applicant or the licensee (in the case of an applicant, updates its involve any provisions requiring the
may use either version of the Code Case application) or until the licensee’s 120- preparation of a backfit analysis or
(subject, however, to whatever change month ISI or IST update interval documentation demonstrating that one
requirements apply to its licensing basis expires, after which the continued use or more of the issue finality criteria in
(e.g., 10 CFR 50.59)). of the Code Case is prohibited, unless 10 CFR part 52 are met.
A licensee’s ISI and IST programs NRC authorization is given under
must be updated every 10 years to the § 50.55a(z). If a Code Case is IX. Plain Writing
latest edition and addenda of Section XI incorporated by reference into § 50.55a The Plain Writing Act of 2010 (Pub.
and the OM Code, respectively, that and later a revised version is issued by L. 111–274) requires Federal agencies to
were incorporated by reference into the ASME because experience has write documents in a clear, concise, and
§ 50.55a and in effect 12 months prior shown that the design analysis, well-organized manner. The NRC has
to the start of the next inspection and construction method, examination written this document to be consistent
testing interval. Licensees who were method, or testing method is with the Plain Writing Act as well as the
using a Code Case prior to the effective inadequate; the NRC will amend Presidential Memorandum, ‘‘Plain
date of its revision may continue to use § 50.55a and the relevant RG to remove Language in Government Writing,’’
the previous version for the remainder the approval of the superseded Code published June 10, 1998 (63 FR 31883).
of the 120-month ISI or IST interval. Case. Applicants and licensees should
This relieves licensees of the burden of X. Environmental Assessment and Final
not begin to implement such superseded
having to update their ISI or IST Finding of No Significant
Code Cases in advance of the
program each time a Code Case is Environmental Impact
rulemaking.
revised by the ASME and approved for The Commission has determined
use by the NRC. Code Cases apply to VI. Regulatory Flexibility Certification under the National Environmental
ethrower on DSK3G9T082PROD with RULES

specific editions and addenda, and Code Under the Regulatory Flexibility Act, Policy Act of 1969, as amended, and the
Cases may be revised if they are no 5 U.S.C. 605(b), the NRC certifies that Commission’s regulations in subpart A
longer accurate or adequate, so licensees this rule does not have a significant of 10 CFR part 51, that this rule, if
choosing to continue using a Code Case economic impact on a substantial adopted, would not be a major Federal
during the subsequent ISI or IST number of small entities. This final rule action significantly affecting the quality
interval must implement the latest affects only the licensing and operation of the human environment; therefore, an

VerDate Sep<11>2014 14:56 Jan 16, 2018 Jkt 244001 PO 00000 Frm 00023 Fmt 4700 Sfmt 4700 E:\FR\FM\17JAR1.SGM 17JAR1
Federal Register / Vol. 83, No. 11 / Wednesday, January 17, 2018 / Rules and Regulations 2353

• Members of the general public (i.e., appointment, at the NRC Technical Revision 37; RG 1.147, Revision 18; and
individual, unaffiliated members of the Library, which is located at Two White RG 1.192, Revision 2, once approved by
public who are not regulated or Flint North, 11545 Rockville Pike, the OFR for incorporation by reference,
otherwise subject to the NRC’s Rockville, Maryland 20852; telephone: are reasonably available to all interested
regulatory oversight) and who need 301–415–7000; e-mail: parties.
access to the materials that the NRC Library.Resource@nrc.gov; url:
proposes to incorporate by reference in www.nrc.gov/reading-rm/doc- XV. Availability of Documents
order to participate in the rulemaking. collections/.
The three regulatory guides being Because access to the three regulatory The documents identified in the
incorporated by reference in this rule guides are available in various forms following table are available to
are available without cost and can be and at no cost, the NRC determines that interested persons through one or more
read online, downloaded, or viewed, by the three regulatory guides, RG 1.84, of the following methods, as indicated.

TABLE IV—RULEMAKING RELATED DOCUMENTS
ADAMS accession No./
Document title Federal Register
citation/web link

Proposed Rule Documents:
Proposed Rule—Federal Register notice, March 2, 2016 ........................................................................ 81 FR 10780.
Draft Regulatory Analysis ........................................................................................................................... ML15041A816.
Draft RG 1.84, Revision 37 (DG–1295) ..................................................................................................... ML15027A002.
Draft RG 1.147, Revision 18 (DG–1296) ................................................................................................... ML15027A202.
Draft RG 1.192, Revision 2 (DG–1297) ..................................................................................................... ML15027A330.
Final Rule Documents:
Regulatory Analysis .................................................................................................................................... ML16285A013.
RG 1.84, Revision 37 ................................................................................................................................. ML16321A335.
RG 1.147, Revision 18 ............................................................................................................................... ML16321A336.
RG 1.192, Revision 2 ................................................................................................................................. ML16321A337.
Related Documents:
Draft RG 1.193, ‘‘ASME Code Cases Not Approved for Use,’’ Revision 5. (DG–1298) ........................... ML15028A003.
Federal Register notice—‘‘Incorporation by Reference of American Society of Mechanical Engineers 82 FR 32934.
Codes and Code Cases,’’ July 18, 2017.
Federal Register notice—‘‘Incorporation by Reference of American Society of Mechanical Engineers 80 FR 56820.
Codes and Code Cases,’’ September 18, 2015.
Federal Register notice—‘‘Incorporation by Reference of ASME BPV and OM Code Cases,’’ July 8, 68 FR 40469.
2003.
Federal Register notice—‘‘Fracture Toughness Requirements for Light Water Reactor Pressure Ves- 60 FR 65456.
sels,’’ December 19, 1995.
Information Notice No. 98–13, ‘‘Post-Refueling Outage Reactor Pressure Vessel Leakage Testing Be- ML031050237.
fore Core Criticality,’’ April 20, 1998.
Inspection Report 50–254/97–27 ................................................................................................................ ML15216A276.
Letter from James M. Taylor, Executive Director for Operations, NRC, to Messrs. Nicholas S. Rey- ML14273A002.
nolds and Daniel F. Stenger, Nuclear Utility Backfitting and Reform Group, February 2, 1990.
Materials Reliability Project Report MRP–169 Technical Basis for Preemptive Weld Overlays for Alloy ML101660468.
82/182 Butt Welds in PWRs (Revision 1), EPRI, Palo Alto, CA: 2012. 1025295.
NUREG/CR–6933, ‘‘Assessment of Crack Detection in Heavy-Walled Cast Stainless Steel Piping ML071020409.
Welds Using Advanced Low-Frequency Ultrasonic Methods’’.
White Paper, PVP2012–78190, ‘‘Alternative Acceptance Criteria for Flaws in Ferritic Steel Compo- http://proceedings.asmedigitalcol-
nents Operating in the Upper Shelf Temperature Range,’’ 2012. lection.asme.org/proceeding.
aspx?articleid=1723450.
White Paper PVP2015–45307, ‘‘Options for Defining the Upper Shelf Transition Temperature (Tc) for http://proceedings.asmedigitalcol-
Ferritic Pressure Vessel Steels,’’ 2015. lection.asme.org/proceeding.
aspx?articleid=2471884.

List of Subjects in 10 CFR Part 50 For the reasons set out in the PART 50—DOMESTIC LICENSING OF
preamble and under the authority of the PRODUCTION AND UTILIZATION
Administrative practice and Atomic Energy Act of 1954, as amended; FACILITIES
procedure, Antitrust, Classified the Energy Reorganization Act of 1974,
information, Criminal penalties, as amended; and 5 U.S.C. 552 and 553, ■ 1. The authority citation for part 50
Education, Fire prevention, Fire the NRC is adopting the following continues to read as follows:
protection, Incorporation by reference, amendments to 10 CFR part 50: Authority: Atomic Energy Act of 1954,
Intergovernmental relations, Nuclear secs. 11, 101, 102, 103, 104, 105, 108, 122,
power plants and reactors, Penalties, 147, 149, 161, 181, 182, 183, 184, 185, 186,
ethrower on DSK3G9T082PROD with RULES

Radiation protection, Reactor siting 187, 189, 223, 234 (42 U.S.C. 2014, 2131,
criteria, Reporting and recordkeeping 2132, 2133, 2134, 2135, 2138, 2152, 2167,
requirements, Whistleblowing. 2169, 2201, 2231, 2232, 2233, 2234, 2235,
2236, 2237, 2239, 2273, 2282); Energy

parties’’ includes a broad set of stakeholders
including State-recognized Indian tribes.

VerDate Sep<11>2014 14:56 Jan 16, 2018 Jkt 244001 PO 00000 Frm 00025 Fmt 4700 Sfmt 4700 E:\FR\FM\17JAR1.SGM 17JAR1
Document Created: 2018-10-26 09:56:12
Document Modified: 2018-10-26 09:56:12
Category		Regulatory Information
Collection		Federal Register
sudoc Class		AE 2.7: GS 4.107: AE 2.106:
Publisher		Office of the Federal Register, National Archives and Records Administration
Section		Rules and Regulations
Action		Final rule.
Dates		This final rule is effective on February 16, 2018. The incorporation by reference of certain publications listed in the regulation is approved by the Director of the Federal Register as of February 16, 2018.
Contact		Jennifer Tobin, Office of Nuclear Reactor Regulation, telephone: 301-415-2328, email: [email protected]; or Giovanni Facco, Office of Nuclear Regulatory Research, telephone: 301-415-6337; email: [email protected] Both are staff of the U.S. Nuclear Regulatory Commission, Washington, DC 20555-0001.
FR Citation		83 FR 2331
RIN Number		3150-AJ13
CFR Associated		Administrative Practice and Procedure; Antitrust; Classified Information; Criminal Penalties; Education; Fire Prevention; Fire Protection; Incorporation by Reference; Intergovernmental Relations; Nuclear Power Plants and Reactors; Penalties; Radiation Protection; Reactor Siting Criteria; Reporting and Recordkeeping Requirements and Whistleblowing