[Federal Register Volume 75, Number 192 (Tuesday, October 5, 2010)]
[Rules and Regulations]
[Pages 61321-61337]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2010-24814]


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NUCLEAR REGULATORY COMMISSION

10 CFR Part 50

[NRC 2009-0014]
RIN 3150-AI37


Domestic Licensing of Production and Utilization Facilities; 
Updates to Incorporation by Reference of Regulatory Guide

AGENCY: Nuclear Regulatory Commission (NRC).

ACTION: Final rule.

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SUMMARY: The Nuclear Regulatory Commission (NRC) is amending its 
regulations to incorporate by reference the latest revisions of two 
previously incorporated regulatory guides (RGs) approving new and 
revised Code Cases published by the American Society of Mechanical 
Engineers (ASME). The RGs which are incorporated by reference are RG 
1.84, ``Design, Fabrication, and Materials Code Case Acceptability, 
ASME Section III,'' Revision 35, and RG 1.147, ``Inservice Inspection 
Code Case Acceptability, ASME Section XI, Division 1,'' Revision 16. 
This action allows nuclear power plant licensees, and applicants for 
standard design certifications, standard design approvals, and 
manufacturing licenses under the regulations that govern license 
certifications, and approves the nuclear power plants to use the Code 
Cases listed in these RGs as alternatives to requirements in the ASME 
Boiler and Pressure Vessel (BPV) Code regarding the construction and 
inservice inspection (ISI) of nuclear power plant components. 
Concurrent with this action, the NRC is publishing a notice of the 
issuance and availability of the RGs in the Federal Register. As a 
result of these related actions, the Code Cases listed in these RGs are 
incorporated by reference into the NRC's regulations and are deemed to 
be legally-binding NRC requirements.

DATES: The rule is effective on November 4, 2010. The incorporation by 
reference of RG 1.84, ``Design, Fabrication, and Materials Code Case 
Acceptability, ASME Section III,'' Revision 35 (July 2010), and RG 
1.147, ``Inservice Inspection Code Case Acceptability, ASME Section XI, 
Division 1,'' Revision 16 (July 2010) is approved by the Director of 
the Office

[[Page 61322]]

of the Federal Register as of November 4, 2010.

ADDRESSES: You can access publicly available documents related to this 
document using the following methods:
    NRC's Public Document Room (PDR): The public may examine and have 
copied for a fee publicly available documents at the NRC's PDR, Public 
File Area O1 F21, One White Flint North, 11555 Rockville Pike, 
Rockville, Maryland 20852.
    NRC's Agencywide Documents Access and Management System (ADAMS): 
Publicly available documents created or received at the NRC are 
available electronically at the NRC's electronic reading room at http://www.nrc.gov/reading-rm/adams.html. From this page, the public can gain 
entry into ADAMS, which provides text and image files of NRC's public 
documents. If you do not have access to ADAMS or if there are problems 
in accessing the documents located in ADAMS, contact the NRC's PDR 
reference staff at 1-800-397-4209, 301-415-4737, or by e-mail to 
[email protected].
    Federal Rulemaking Web site: Public comments and supporting 
materials related to this final rule can be found at http://www.regulations.gov by searching on Docket ID: NRC-2009-0014.

FOR FURTHER INFORMATION CONTACT: Manash K. Bagchi, Office of Nuclear 
Reactor Regulation, U.S. Nuclear Regulatory Commission, Washington, DC 
20555-0001, telephone 301-415-2905, or by e-mail [email protected].

SUPPLEMENTARY INFORMATION:
I. Background
II. Response To Public Comments
    A. Overview of Public Comments
    B. NRC Responses to Public Comments
III. NRC Approval of New and Amended ASME Code Cases
IV. Paragraph by Paragraph Discussion
V. Availability of Documents
VI. Voluntary Consensus Standards
VII. Finding of No Significant Environmental Impact: Environmental 
Assessment
VIII. Paperwork Reduction Statement
    Public Protection Notification
IX. Regulatory Analysis
X. Regulatory Flexibility Certification
XI. Backfit Analysis
XII. Congressional Review Act

I. Background

    The ASME develops and publishes the ASME BPV Code, which contains 
requirements for the design, construction, and ISI of nuclear power 
plant components, and the Code for Operation and Maintenance of Nuclear 
Power Plants (OM Code), which contains requirements for inservice 
testing (IST) of nuclear power plant components. In response to BPV and 
OM Code user requests, the ASME develops ASME Code Cases which provide 
alternatives to BPV and OM Code requirements under special 
circumstances.
    The NRC approves and/or mandates the use of the ASME BPV and OM 
Code in Title 10 of the Code of Federal Regulations (10 CFR) Part 
50.55a through the process of incorporation by reference. As such, each 
provision of the ASME Codes incorporated by reference into, and 
mandated by, 10 CFR 50.55a constitutes a legally-binding NRC 
requirement imposed by rule. As noted above, ASME Code Cases represent 
alternative approaches for complying with provisions of the ASME BPV 
and OM Codes. Accordingly, the NRC periodically amends Sec.  50.55a to 
incorporate by reference NRC RGs listing new and revised\1\ ASME Code 
Cases which the NRC approves for use as alternatives to the BPV Code 
and the OM Code. See 68 FR 40469 (July 8, 2003). It should be noted 
that for this particular rulemaking, RG 1.192, ``Operations and 
Maintenance Code Case Acceptability, ASME OM CODE,'' is not being 
revised because there are no new or revised OM Code Cases considered by 
the NRC in this rulemaking. New and revised OM Code Cases published by 
the ASME since RG 1.192 was first issued, will be addressed in the next 
proposed amendment. This final rule will continue the NRC's practice of 
incorporating by reference the RGs listing the most current set of NRC-
approved ASME Code Cases. ASME Code Cases may be approved for use, 
either unconditionally or with conditions stated in the relevant RGs. 
In developing the RGs, the NRC staff reviews ASME BPV and OM Code 
Cases, determines the acceptability of each Code Case, and publishes 
its findings in RGs. The RGs are revised periodically as new Code Cases 
are published by the ASME. The NRC incorporates by reference the RGs 
listing acceptable and conditionally acceptable ASME Code Cases into 10 
CFR 50.55a. Currently, NRC RG 1.84, Revision 34, ``Design, Fabrication, 
and Materials Code Case Acceptability, ASME Section III''; RG 1.147, 
Revision 15, ``Inservice Inspection Code Case Acceptability, ASME 
Section XI, Division 1;'' and RG 1.192, ``Operation and Maintenance 
Code Case Acceptability, ASME OM Code'' are incorporated into the NRC's 
regulations at 10 CFR 50.55a, Codes and standards.
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    \1\ ASME Code Cases can be categorized as one of two types: new 
and revised. A new Code Case provides for the first time an 
alternative to specific ASME Code provisions or addresses a new 
need. A revised Code Case is 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 regulatory guides which have been incorporated 
by reference into 10 CFR 50.55a.
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II. Response to Public Comments

    The NRC published a proposed rule that would incorporate by 
reference RG 1.84, Revision 35, and RG 1.147, Revision 16, on June 2, 
2009, 74 FR 26303. On the same date, the NRC published a parallel 
notice of availability of draft regulatory guides and opportunity for 
public comment. See 74 FR 26440. The NRC provided a 75-day public 
comment period for both the proposed rule and the draft RGs, which 
ended on August 17, 2009.

A. Overview of Public Comments

    The NRC received nineteen comment letters on the draft regulatory 
guides and three general comments on the proposed rule. The following 
table lists the commenters, their affiliation, and the accession number 
to locate each comment letter. In addition, the Code Cases for which 
each commenter submitted comments are listed. Several general comments 
were also received.

    Comment Letters Received on Draft: Regulatory Guide 1.84, Revision 35 (DG-1191); Regulatory Guide 1.147,
                       Revision 16 (DG-1192); REGULATORY GUIDE 1.193, Revision 3 (DG-1193)
----------------------------------------------------------------------------------------------------------------
        Commenter No.                   Name             Affiliation/abbreviation        ADAMS Accession No.
----------------------------------------------------------------------------------------------------------------
1...........................  Raymond West...........  Private Citizen/RW..........  ML091540204
                                                       N-513-2/N-513-3.............
2...........................  Ronald Clow............  DBA Xcel Energy/Xcel........  ML091700640
                                                       N-508-3/N-508-4.............

[[Page 61323]]

 
3...........................  C.L. Funderburk........  Dominion Resources Services,  ML091750096
                                                        Inc./DRS.
                                                       N-513-2/N-513-3.............
4...........................  Brian Erler............  American Society of           ML092190138
                                                        Mechanical Engineers/ASME.
                                                       N-71-18, N-416-4, N-504-4, N-
                                                        513-2/N-513-3, N-661-1, N-
                                                        702, N-747, N-751.
5...........................  Edward Gerlach.........  Private Citizen/EG..........  ML092190139
                                                       Two general comments--N-416-
                                                        4, N-504-4, N-638-4, N-661-
                                                        1.
6...........................  Lee Goyette............  Pacific Gas & Electric        ML092190140
                                                        Company/PGE.
                                                       N-597-2.....................
7...........................  Charles Wirtz..........  ASME BPV Standards Committee  ML092220042
                                                        on Nuclear Inservice
                                                        Inspection/CW.
                                                       N-619, N-648-1..............
8...........................  Robert Sisk............  Westinghouse Electric         ML092220043
                                                        Company/WECRS.
                                                       N-655-1, N-757-1, N-759-2, N-
                                                        782, N-759.
9...........................  Patrick O'Regan........  Electric Power Research       ML092240576
                                                        Institute/EPRI.
                                                       N-716.......................
10..........................  Kevin Hall.............  Private Citizen/KH..........  ML092250165
                                                       N-716.......................
11..........................  James Riley............  Nuclear Energy Institute/NEI  ML092370059
                                                       General comment--N-504-4, N-
                                                        508-3/N-508-4, N-597-2.
12..........................  R.M. Krich.............  Tennessee Valley Authority/   ML092370060
                                                        TVA.
                                                       N-520-1/N-520-2, N-702......
13..........................  J.A. Gresham...........  Westinghouse Electric         ML092370665
                                                        Company/WECJAG.
                                                       N-655-1, N-757-1, N-759-2, N-
                                                        782, N-759.
14..........................  Scott Chesworth........  Structural Integrity          ML092370061
                                                        Associates, Inc./SIASC.
                                                       N-716.......................
15..........................  Miroslav Trubelja......  Structural Integrity          ML092370062
                                                        Associates, Inc./SIAMT.
                                                       N-716.......................
16..........................  Sandra Sowah...........  Structural Integrity          ML092370063
                                                        Associates, Inc./SIASS.
                                                       N-716.......................
17..........................  Daniel R. Cordes.......  ASME Section XI Subgroup Non  ML092370064
                                                        Destructive Examination/DC.
                                                       N-583.......................
18..........................  Marcus N. Bressler.....  Private Citizen/MB..........  ML092400356
                                                       N-71-18.....................
19..........................  T.S. Rausch............  PPL Susquehanna, LLC/PPL....  ML092590124
                                                       N-416-4, N-504-4, N-638-4...
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Summary of Comments:

    The proposed rule provided a 75-day comment period. A total of 19 
comment letters were received from four private citizens, four utility 
organizations, seven industry groups that provide engineering and 
inspection services to the utilities, three associated with the ASME, 
and the Nuclear Energy Institute. Three general comments were received 
on the proposed rule regarding the need for editorial corrections 
(although two of the comments received from different commenters 
address the same subject). The majority of the comments received relate 
to Section XI Code Cases. Two comments were submitted requesting that 
the NRC include later versions of certain Code Cases in the final 
guide; 7 comments request that the NRC reconsider conditions on certain 
Code Cases; 1 comment requests clarification of a condition; and 3 
comments provide additional technical information to justify moving 
certain Code Cases from RG 1.193 (Code Cases disapproved for use) to 
Regulatory Guide 1.147.

B. NRC Responses to Public Comments on Draft Regulatory Guide

    Responses have been organized in two groups: Group I: Adopted 
Comments, that includes comments raising issues and concerns directly 
related to this rule, and have been adopted; and Group II: Comments not 
Adopted, that includes comments raising issues and concerns that are 
not directly connected to this particular rule, although they are 
generally relevant to this rule but have not been adopted.
Group I--Adopted Comments
    General Comments: Edward Gerlach commented (comment EG1) that Table 
2 in the proposed rulemaking listed accession numbers for Draft 
Regulatory Guides dated April 2009. The NRC's electronic reading room 
contains later versions of these Draft Guides dated June 2009.
    Response: The accession numbers in Table 2 of the final rulemaking 
have been corrected to reflect the final versions of the regulatory 
guides. In addition, the accession numbers for all the documents have 
been verified.
    Comment: Two commenters acknowledge that the titles of Code Cases 
N-712 and N-730 in Table 1 of the proposed rule had been inadvertently 
switched and should be corrected (comments EG2 and NEI3).
    Response: The NRC agrees that there was an error in the rulemaking 
table. This table is not included in the final rulemaking, and no 
further NRC action is necessary.
RG 1.84
Code Case N-71-18
    Comment: Two comments (ASME 1 and ASME 2) were received from the 
American Society of Mechanical Engineers on Code Case N-71-18, 
``Additional Materials for Subsection NF, Class 1, 2, 3, and MC 
Component Supports Fabricated by Welding, Section III, Division 1.'' 
The first comment (ASME1) was that the NRC proposed to impose the same 
conditions on Code Case N-71-18 as were imposed

[[Page 61324]]

on Code Case N-71-17, and some of the conditions are not appropriate to 
Revision 18 as certain references have changed (conditions (3) and 
(4)).
    The second comment (ASME2) was that there appears to be confusion 
regarding whether or not the Code Case applies to component supports 
(condition 6). Marcus Bressler also commented on this Code Case 
(comment MB1) stating that conditions (1) and (2) aren't applicable to 
Revision 18 because the Code Case has no materials listed with a 
minimum tensile strength above 125 ksi.
    Response: The NRC agrees with the ASME that the paragraphs 
referenced in conditions (3) and (4) should be modified. When Code Case 
N-71-17 was revised as Code Case N-71-18, certain references were 
rearranged. The editorial corrections have been made in the final guide 
so that the conditions are consistent with the references in the 
revised Code Case. The requirements for weld filler material hydrogen 
content were moved to paragraph 4.2 (previously in paragraph 5.3), and 
the requirements for postweld heat treatment were moved from paragraphs 
16.2.1 and 16.2.2 to paragraphs 15.2.1 and 15.2.2 (paragraphs 16.2.1 
and 16.2.2 no longer exist). As noted by the commenter, the conditions 
in Draft RG 1.84 should have been modified to be consistent. The 
conditions have been corrected in the final guide. With regard to the 
ASME's second comment (and similar comment from Marcus Bressler) on 
condition (6), the NRC's understanding of the intent of the provisions 
in the Code Case is not in agreement with the commenter's 
understanding, (i.e., that the fracture toughness requirements as 
listed in this Code Case address Class 1, Class 2, and Class 3 
component supports in addition to piping supports). The NRC believes 
that the fracture toughness requirements listed in Code Case N-71-18 
apply only to piping supports. Implementation of this Code Case was 
approved by the NRC on this basis. Cognizant NRC staff will initiate 
discussions with the appropriate ASME committees.
    The NRC agrees with Marcus Bressler that Code Case N-71-18 does not 
list materials with a minimum tensile strength exceeding the value of 
125 kilograms per square inch. However, the NRC believes that 
conditions (1) and (2) are appropriate for this Code Case because they 
provide a cautionary note that high strength materials are susceptible 
to brittleness and stress corrosion cracking. As such, the NRC declines 
to adopt the comment related to conditions (1) and (2), and no change 
was made to the RG as the result of this comment.
RG 1.147
Code Case N-416-4
    Comment: Three commenters (comments ASME3, EG3, and PPL1) requested 
that the NRC should not adopt the proposed condition requiring that 
when using Code Case N-416-4 ``Alternative Pressure Test Requirement 
for Welded or Brazed Repairs, Fabrication Welds or Brazed Joints for 
Replacement Parts and Piping Subassemblies, or Installation of 
Replacement Items by Welding or Brazing, Classes 1, 2, and 3, Section 
XI, Division 1,'' that Nondestructive Examination (NDE) be performed 
for welded or brazed repairs and fabrication and installation joints as 
specified by the methods and acceptance criteria of the applicable 
subsection of the 1992 Edition of Section III. The commenters believe 
that the Section III NDE requirements are overly conservative relative 
to the NDE requirements of Section XI.
    Response: The NRC disagrees that the condition is not needed. The 
NRC does not believe that an adequate argument was provided to justify 
deletion of the condition to require that NDE be performed for welded 
or brazed repairs and fabrication and installation joints in accordance 
with the methods and acceptance criteria of the applicable subsection 
of the 1992 Edition of Section III.
    As discussed in the proposed rule for Draft Regulatory Guide DG-
1192 for certain welding repairs or replacements, the previous version 
of this Code Case (Code Case N-416-3) permitted a system leakage test 
to be performed in lieu of performing a hydrostatic pressure test 
provided that certain requirements are met. A requirement was that NDE 
be performed on welded repairs, and that fabrication and installation 
of joints be as specified by the methods and acceptance criteria of the 
applicable subsection of the 1992 Edition of Section III. When Code 
Case N-416 was originally developed, the NRC agreed to the performance 
of system leakage testing in lieu of hydrostatic testing provided that 
NDE performed in conjunction with the repair met the requirements of 
the 1992 Edition of Section III. The requirement to perform NDE under 
Section III was removed when Code Case N-416-4 was issued.
    The NRC believes that many analyses of the effectiveness and 
reliability of the later NDE requirements have demonstrated the 
inadequacies of earlier Code NDE requirements. Improvements in NDE have 
significantly increased the probability of detecting defects. With 
regard to leakage tests, the NRC staff's position was that even though 
the primary purpose of a leakage test is the leak-tightness of the 
primary pressure boundary, some additional assurance of primary 
boundary integrity was provided by the higher pressure hydrostatic 
test. Based on the industry conclusions that: the increased stress from 
a hydrostatic test is extremely unlikely to cause a subsurface defect 
to grow through-wall (and therefore, leak during a test) and the 
stresses involved in a hydrostatic test are similarly unlikely to cause 
leakage even with the presence of a through-wall flaw, the need for 
effective and reliable NDE is even greater.
    Because the NRC has determined that pressure tests are not adequate 
for ensuring structural integrity (i.e., adequate component repair and 
replacement), the NRC believes it to be paramount that high quality NDE 
be performed. Thus, the NRC rejects the argument that the lower quality 
NDE as conducted to earlier Codes is adequate. Accordingly, the NRC 
declines to adopt the comment, and no change was made to the RG as the 
result of this comment.
Code Case N-504-3, N-504-4
    Comment: Four commenters (comments ASME4, EG4, NEI2, and PPL2) 
believe that all of the conditions the NRC proposed for Code Case N-
504-4, ``Alternative Rules for Repair of Class 1, 2, and 3 Austenitic 
Stainless Steel Piping, Section XI, Division 1,'' are unnecessary and 
should be removed in the final RG. One of the conditions requires that 
the provisions of Section XI, Nonmandatory Appendix Q, ``Weld Overlay 
Repair of Class 1, 2, and 3 Austenitic Stainless Steel Piping 
Weldments,'' Section XI, must also be met in addition to the provisions 
of the Code Case was retained from RG 1.147, Revision 15, Code Case N-
504-3. The commenters believe that changes to the Code Case and to 
Appendix Q address the NRC's concerns relative to Appendix Q and 
therefore this condition is no longer required. With regard to 
condition (a), the commenters believe that criteria in Code Case N-504-
4 are more conservative than the proposed condition, and therefore 
condition (a) is not required. The commenters believe that conditions 
(b) and (c) regarding surface finish are redundant to criteria in Code 
Case N-504-4 and Supplement 11 of Appendix VIII. Finally, it was stated 
that there is no technical basis for restricting the use

[[Page 61325]]

of radiographic examination (condition (d)).
    Response: The NRC disagrees that the conditions should be removed. 
It is true that a number of changes were made to the criteria of the 
Code Case and to Appendix Q as a result of concerns raised by the NRC. 
However, differences remain between Appendix Q and Code Case N-504-4 
that were not addressed in the public comments submitted. For example, 
Appendix Q has requirements pertaining, in part, to the inspection and 
design of a structural weld overlay whereas the Code Case does not. 
Until the differences between Appendix Q and N-504-4 are addressed, the 
condition to follow Appendix Q must be retained.
    It is clear from the comments, however, that condition (a) should 
be revised to make the objective clearer. The commenters believe that 
the limitations in the Code Case on laminar flaw size are more 
conservative than the proposed NRC condition, which indicates that the 
intent of the condition was not apparent. It is agreed that Code Case 
N-504-4 addresses laminar flaws, but the NRC does not believe that the 
provision is stringent or clear.
    Condition (a) in the regulatory guide is needed to limit the number 
of laminar flaws in the weld overlay. If a weld overlay contains too 
many laminar flaws, the flaws may affect the structural integrity of 
the weld overlay. Accordingly, condition (a) has been revised to read 
``the total laminar flaw area shall not exceed 10 percent of the weld 
surface area, and no linear dimension of the laminar flaw area shall 
exceed the greater of 3 inches or 10 percent of the pipe 
circumference.''
    The NRC does not agree with regard to the comment that Code Case N-
504-4 and Supplement 11 to Appendix VIII already address improving the 
surface finish of piping welds and therefore conditions (b) and (c) are 
unnecessary. The provision in Code Case N-504-4 cited by the 
commenters, ``Grinding and machining of the as-welded overlay surface 
may be used to improve the surface finish for such examinations'' is 
not a requirement and does not specify any criterion that must be met. 
Supplement 11, 1.1(c) states, ``The surface condition of at least two 
specimens shall approximate the roughest surface condition for which 
the examination procedure is applicable.'' Thus, there is no specific 
criterion that must be met.
    The NRC does not agree regarding the request to delete condition 
(d) and the restriction against radiographic testing (RT). Studies have 
been conducted indicating that radiography has the potential for 
detecting planar flaws with high reliability only under favorable 
conditions. Code Case N-504-4 provides alternative provisions for 
repairing austenitic stainless steel piping. Thus, the NRC believes 
this is a valid concern that planar flaws, typical flaws found during 
inservice inspections as opposed to volumetric flaws that result from 
fabrication, may not be detected through RT. Especially considering 
that digital radiographic testing may be used and factors such as 
exposure, screens, magnification, and source-target-detector distances 
have yet to be clearly defined. Without supporting technical 
information to indicate the reliability of RT for the particular 
conditions of interest, the NRC concludes that this condition to Code 
Case N-504-4 is necessary.
Code Cases N-513-2, N-513-3
    Three commenters (comments RW1, ASME7, and DRS1) requested that 
Code Case N-513-3 be approved in final RG 1.147. They assert that 
licensees that have updated their inservice inspection (ISI) plans to 
the 2004 Edition of Section XI can no longer use Code Case N-513-2 
because of limits on its applicability. Code Case N-513-3, which was 
recently published by the ASME in Supplement 8 to the 2007 Edition, 
addresses the applicability issue.
    Response: The NRC agrees with the comment with one condition. Code 
Case N-513-2 was unconditionally approved in Revision 15 of RG 1.147. 
The applicability of the Code Case was through the 2001 Edition with 
the 2003 Addenda. The applicability was purposefully not extended by 
the ASME beyond the 2003 Addenda by the ASME because a revision to the 
Code Case (N-513-3) had been developed for application to later edition 
and addenda. The purpose of the revision to the Code Case (N-513-3) was 
to provide additional guidance to evaluate through-wall, nonplanar 
flaws. Users of Code Case N-513-2 had found the acceptance criterion 
for the branch reinforcement evaluation approach to be ambiguous, and 
there was a lack of adequate guidance for dispositioning nonplanar flaw 
combinations.
    The NRC has reviewed the additional guidance resulting in Code Case 
N-513-3 and has determined that the additions are indeed clarifications 
and not technical changes. However, the NRC does not agree with one 
change regarding the time frame for repairs. Accordingly, Code Case N-
513-3 has been conditionally approved in the final RG. Code Case N-513 
was developed to reduce the number of plant shutdowns required to 
immediately correct insignificant degradation in Class 2 or 3 lower 
energy piping (maximum operating temperature of 200 [deg]F and maximum 
operating pressure of 275 psig). Revisions 0 through 2 of the Code Case 
stated that certain flaws may be acceptable without performing a repair 
or replacement activity for a limited period, not exceeding the time to 
the next scheduled outage. The time frame for temporary acceptance of 
the degradation was modified in Code Case N-513-3 from ``next scheduled 
outage'' to ``not to exceed 26 months from the initial discovery of the 
condition.'' The basis for NRC approval of the original time frame was 
that the degraded condition would be monitored and evaluated during 
continued operation, and operation was only approved until plant 
shutdown. Once the plant was shut down, it was expected that the 
degraded piping would be repaired. The extension of the time frame to 
26 months from the discovery of the condition could permit operation 
through several outages. The NRC believes that the original time frame 
is prudent. The Class 2 and 3 systems addressed by the Code Case 
contain safety-significant components, and repairs should be performed 
at the first opportunity. Accordingly, Revision 3 of the Code Case has 
been included in the final guide with the condition that the repair or 
replacement activity must be completed during the next scheduled 
outage.
Code Case N-583
    Comment: A commenter (comment DC1) requests that the NRC consider 
the removal of the conditions on the use Code Case N-583, ``Annual 
Training Alternative, Section XI, Division 1,'' requiring practice ``6 
months prior'' to performing exams, and leave ``as-is'' in the case to 
``annually.'' The commenter further suggests that if this is not 
acceptable, then a 6-month ``proficiency'' similar to the ``annual 
proficiency'' specified and implemented by ASNT CP-189 should be 
adopted. The commenter states that performing the practice on specimens 
with actual cracks is definitely beneficial, and that the ASME should 
adopt this position. However, after 10 years of implementation, the 
twice yearly requirement of the ``hands on'' practice has become 
significantly burdensome, specifically with logistics and cost of 
implementation, particularly for owners and vendors who generally 
employ the PDI qualified individuals.
    Response: The NRC disagrees with the comment that the condition 
requiring practice six months prior to performing examinations should 
be deleted.

[[Page 61326]]

    With respect to the commenter's recommendation to adopt a 6-month 
proficiency examination, the NRC believes this may be a viable option, 
but it would be more appropriate if the initiative and the technical 
basis for such an approach were developed by the industry. The NRC 
believes that the current requirement is justified. EPRI has conducted 
several studies on the relationship of education, training, and 
experience. The correlation was at best low and in some instances (such 
as experience versus ability to detect intergranular stress corrosion 
cracking (IGSCC)), the data showed a negative correlation. For example, 
a group of twelve ultrasonic examiners with approximately one-year of 
ultrasonic examination experience but with three weeks of quality 
training had a pass rate of 92.7 percent on the IGSCC detection 
practical examination. However, the success rate of individuals with 
experience averaging in excess of 7.7 years was only 37.6 percent.
    One of the major keys to effective training is to perform a 
detailed task and skills analysis to determine the NDE parameters that 
impact detection performance. A number of these parameters such as 
illumination levels and calibration procedures are addressed in the 
conventional training course outlines. However, most outlines do not 
address the more subtle parameters such as visual search procedures and 
ultrasonic manual scanning techniques to assure coverage and effective 
beam orientation, nor do the outlines address the evaluation of subtle 
ultrasonic signal characteristics such as signal rise, decay time, and 
pulse duration. As appropriate, these issues must be identified and 
included in the training provided to examiners. Computer-based 
training, through the use of animations, simulation, and actual data, 
is evolving as an effective way to transfer this information.
    In addition, many individuals do not routinely perform 
examinations, or they may not have recently had to interpret signals 
from cracks. Signals can be difficult to interpret. Although programs 
employ ``qualified'' personnel using qualified'' procedures, operating 
experience, round robin trials, and research results have shown that 
skills will diminish without frequent training. Personnel and 
procedures must not only be qualified, but must also be effective. 
Experience and studies indicate that the examiner must practice on a 
frequent basis to maintain the capability for proper interpretation. In 
addition, these studies have shown that this capability begins to 
diminish within approximately 6 months if skills are not maintained. 
Class room instruction is not sufficient to maintain an examiner's 
skills in this highly specialized skill area. Examiner training needs 
to focus on hands-on training with flawed specimens.
    With respect to the commenter's other recommendation to adopt a 6-
month proficiency examination, the NRC believes this may be a viable 
option, but it would be more appropriate if the initiative and the 
needed technical basis for such an approach were developed by the 
industry. Accordingly, no changes are being made to the conditions at 
this time.
Code Case N-638-4
    Comments: Two commenters (comments EG5 and PPL3) believe that Code 
Case N-638-4, ``Similar and Dissimilar Metal Welding Using Ambient 
Temperature Machine GTAW Temper Bead Technique, Section Xl, Division 
1,'' addresses the NRC's concern that the Section XI examination volume 
and acceptance criteria were not appropriate for the subject weld 
repair. Paragraph 4(a) of the Code Case requires that the examination 
of the repair be performed as specified by and meet the acceptance 
criteria of the Construction Code or Section III. Therefore, the 
condition is no longer necessary.
    Response: The NRC disagrees that Code Case N-638-4 addresses the 
issue. The commenter is correct that paragraph 4(a)(4) of Code Case N-
638-4 specifies the acceptance criteria for the surface and volumetric 
examination as the Construction Code or Section III; however, Code Case 
N-638-4 still does not specify that a demonstration must be performed 
with representative samples that shows the ultrasonic examination 
technique is capable of detecting construction type flaws in the 
repaired volume. Thus, a condition is required to address this issue. 
Based on the public comments received, the NRC believes that condition 
(1) on Code Case 638-4 should be revised to be clearer. Accordingly, 
the condition has been reworded to explicitly require demonstration 
with construction type flaws. Further, as a result of the review of the 
public comments, the NRC realizes that an additional issue must be 
addressed. Paragraph 3(d) of the Code Case establishes a maximum weld 
interpass temperature, and paragraph 3(e) requires that the weld 
interpass temperature be determined through one of the methods listed 
in subparagraphs (e)(1), (e)(2), and (e)(3). Subparagraph (e)(1) lists 
methods by which the temperature may directly be determined, 
subparagraph (e)(2) provides a method to calculate the weld interpass 
temperature, and subparagraph (e)(3) allows the use of a test coupon to 
determine the maximum weld interpass temperature. Code Case N-638-4 
does not restrict or choose one method over another. Ensuring that the 
weld interpass temperature is not exceeded is important in obtaining a 
quality weld (e.g., in terms of corrosion resistance, notch toughness). 
Direct measurement is the most reliable method for ensuring that the 
maximum temperature is not exceeded. The NRC recognizes that direct 
measurement is not always feasible, but direct measurements should be 
used whenever possible before alternatives such as those described in 
paragraphs 3(e)(2) and 3(e)(3) are used. This position is consistent 
with past precedent on this issue. Thus, a second condition has been 
added in the final guide stating that ``The provisions of paragraphs 
3(e)(2) or 3(e)(3) may only be used when it is impractical to use the 
interpass temperature measurement methods described in 3(e)(1), such as 
in situations where the weldment area is inaccessible (e.g., internal 
bore welding) or when there are extenuating radiological conditions.''
    Accordingly, the condition (1) of the Code Case 638-4 in final 
Revision 16 to RG 1.147 has been revised to read as follows: 
``Demonstration of ultrasonic examination of the repaired volume is 
required using representative samples which contain construction type 
flaws.''
Code Case N-661-1
    Comments: Two commenters (comments ASME5 and EG6) stated that Code 
Case N-661-1, ``Alternative Requirements for Wall Thickness Restoration 
of Class 2 and 3 Carbon Steel Piping for Raw Water Service, Section XI, 
Division 1,'' addresses the NRC's concerns discussed in the proposed 
rule.
    Therefore, the conditions that address root cause and weld overlays 
can be deleted. The commenters stated that the only issue that may need 
clarification is the definition of ``cycle or refueling outage.''
    Response: The NRC agrees that condition (b) on the Code Case can be 
deleted. The NRC staff has reassessed paragraph 1(d) of the Code Case 
and agrees that it addresses the issue of multiple repairs to the same 
location through weld overlay. The NRC disagrees however, that 
condition (a), ``if the root cause of the degradation has not been 
determined, the repair is only acceptable for one cycle,'' can be 
deleted. The NRC believes that the condition is still required to 
provide the needed clarity on two issues. First, the

[[Page 61327]]

second sentence of paragraph 7(b) of the Code Case uses the term 
``cause'' rather than ``root cause.'' These terms have specific meaning 
to licensees. The NRC has determined that for the purpose of 
maintaining safety, it is appropriate to require a root cause analysis 
which is more rigorous than merely inferring the ``cause'' of the 
degradation. The second issue relative to clarity is the use of the 
term ``one fuel cycle.'' As discussed in the proposed rule, it is 
unclear what one fuel cycle actually infers if a repair is performed in 
mid-cycle. It may be interpreted that the repair is acceptable for the 
remainder of the current fuel cycle plus the subsequent fuel cycle. In 
addition, other terms are used in the Code Case such as ``one cycle.'' 
Although the Code Case provision and regulatory guide condition (a) are 
otherwise nearly identical, the NRC believes that for the sake of 
clarity and to ensure that a suitable re-inspection frequency has been 
established when the cause of the degradation is unknown or when the 
potential for hydrogen cracking exists due to the welding conditions, 
the condition is needed so that users are clear that what is meant is 
by ``next refueling outage.''
    With regard to condition (c) which states ``When through-wall 
repairs are made by welding on surfaces that are wet or exposed to 
water, the weld overlay repair is only acceptable until the next 
refueling outage,'' the NRC has the same concern regarding ``next 
refueling outage.''
    While it is agreed that paragraphs 4(c) and 5(b) of the Code Case 
deal with the technical issues, the term one cycle is used. 
Accordingly, the NRC is retaining this condition in the final RG to 
ensure that it is clear that the requirement applies at the next 
refueling outage.
Code Case N-716
    Comment: Five commenters (comments EPRI1, KH1, SIASC1, SIAMT1, and 
SIASS1) suggested that the NRC conditionally approve Code Case N-716, 
``Alternative Piping Classification and Examination Requirements, 
Section XI, Division 1,'' in the final Revision 16 of RG 1.147. The NRC 
has conditionally approved requests from four plants to use provisions 
similar to those in the Code Case. Based on the approvals, lessons 
learned from the pilot plant applications, as well as a number of 
follow-on applications, the lessons learned could be incorporated into 
the final Revision 16 of RG 1.147 to allow plants to use this Code Case 
in the short term. Approval of the Code Case for generic use will not 
only result in a substantial reduction in worker exposure and radwaste, 
but will also reduce unnecessary NRC staff burden, as compared to 
waiting until the Code Case is revised by ASME and subjected to further 
NRC review.
    Response: The Code Case has not been included in final Revision 16 
to RG 1.147. The NRC is continuing to gain experience with the review 
of risk-informed inservice inspection (RI-ISI) programs based, in part, 
on Code Case N-716. The NRC staff has not yet systematically identified 
all differences between the method described in the Code Case and those 
approved at individual licensees, nor has the staff received any such 
description by industry.
    One issue not yet explored in the plant specific submittals is the 
application of Revision 2 of RG 1.200, ``An Approach for Determining 
the Technical Adequacy of Probabilistic Risk Assessment Results for 
Risk-Informed Activities,'' which expands the scope of initiating 
events whose evaluation is required to be consistent with the ASME/ANS 
RA-Sa-2009 PRA Standard.
    The review of EPRI Topical Report 1018427, ``Nondestructive 
Evaluation: PRA Technical Adequacy Guidance for RI-ISI Programs'' is 
proceeding according to schedule. A request for additional information 
(RAI) was transmitted to EPRI on September 15, 2009. An NRC staff 
endorsed document describing acceptable PRA quality requirements for 
RI-ISI will be necessary for the NRC to endorse some version of Code 
Case N-716 in RG 1.147. Accordingly, Code case N-716 has not been 
included in the final revision 16 of RG 1.147.
Code Case N-751
    The American Society of Mechanical Engineers (comment ASME6) does 
not believe that Code Case N-751, ``Pressure Testing of Containment 
Penetration Piping, Section XI, Division 1,'' should be conditioned 
because the Construction Code, which may or may not have included 
provisions for NDE of piping welds in penetrations, continues to apply. 
Therefore, the presence or absence of specific NDE provisions in the 
Construction Code should not be a reason to condition the use of the 
Code Case.
    Response: The NRC disagrees that specific nondestructive 
examination (NDE) requirements are not needed. As discussed in the 
proposed rule, the Code Case would allow an Appendix J Type C test to 
be performed as an alternative to the ASME Code requirement to pressure 
test piping that penetrates a containment vessel, if the piping and 
isolation valves that are part of the containment system are Class 2 
and the balance of the piping system is outside the scope of Section 
XI. The NDE requirement associated with the system leakage test was 
removed from Section XI paragraph IWA-4540 of the 2003 Addenda (and 
later edition and addenda of the ASME Code). In addition, for plants 
that used the ASME B31.1 Code for construction, there was no 
requirement to volumetrically examine certain piping components during 
fabrication.
    Section XI requires NDE per the construction code as part of repair 
and replacement activities. Thus, if a B31.1 plant or a licensee using 
the 2003 Addenda or later performs a repair to certain Class 2 or Class 
3 piping, there is no requirement to perform NDE. Volumetric 
examination after repair or replacement is required to ensure high 
quality welds. It was stated in the public comments that the industry 
has concluded that pressure tests are not adequate for ensuring 
structural integrity (i.e., adequate component repair and replacement). 
Therefore, it is paramount that high quality NDE be performed. 
Volumetric examination ensures high quality welds capable of performing 
their design function for the life of the component. Therefore, the 
condition on the use of Code Case N-751 that when a 10 CFR part 50, 
Appendix J, Type C test is performed as an alternative to the 
requirements of IWA-4540 (IWA-4700 in the 1989 edition through the 1995 
edition) during repair and replacement activities, nondestructive 
examination must be performed as specified by IWA-4540(a)(2) of the 
2002 Addenda of Section XI has been retained in the final RG.
Group II--Comments not Adopted
Code Case N-508-4
    Comment: Two commenters (comments Xcel1 and NEI4) requested that 
Code Case N-508-4 be listed in the final RG because the Code Case would 
be beneficial to the industry.
    Response: The NRC declines the suggestion to adopt Code Case 508-4 
in the final guide. It would not be appropriate to include Revision 4 
to the Code Case in the final guide without first having sought public 
comment on such a significant expansion of the scope of the Code Case. 
Code Case N-508-3, which was unconditionally approved in Revision 15 of 
RG 1.147, allowed snubbers and relief valves to be rotated from stock 
and installed on components for the purpose of testing or preventive 
maintenance. Code Case N-

[[Page 61328]]

508-4 was published by the ASME in Supplement 8 to the 2007 Edition, 
and it significantly expands the list of components through the 
addition of pumps, control rod drive mechanisms, and pump seal 
packages. The Code Cases listed in this supplement will be considered 
in the next draft of RG 1.47 giving the public an opportunity to 
comment on the appropriateness of the scope change of the Code Case.
    With regard to including Code Case N-508-4 in the next draft guide, 
NRC staff have reviewed Code Case N-508-4 and identified an issue. It 
was realized that when Section XI is used to govern snubber examination 
and testing, Footnote 1, which was later added to the Code Case, 
conflicts with Subsection IWF, Section XI, up to and including the 2004 
Edition through 2005 Addenda. Footnote 1 directs the user to implement 
the ASME and OM Code for snubber examination and testing.
    The OM Code was developed in order to have a separate Code for the 
development and maintenance of provisions for the IST of pumps and 
valves. In 1990, the ASME published the initial edition of the OM Code, 
thereby transferring responsibility for these provisions from Section 
XI to the OM Committee. While the use of the OM Code is an option under 
10 CFR 50.55a(b)(3)(v), the examination and testing requirements for 
snubbers are also provided in the 2005 Addenda and earlier editions and 
addenda of Section XI. There is no conflict for licensees who have 
adopted the 2006 Addenda or later editions and addenda of Section XI. 
Other than expansion of the list of components that may be rotated from 
stock and installed on components for the purpose of testing or 
preventive maintenance, Revisions 3 and 4 of the Code Case are 
identical. Thus, Code Case N-508-4 as presently constructed would have 
to be conditioned that Footnote 1 would not apply when the ISI Code of 
record is earlier than Section XI, 2006 Addenda, and Section XI 
requirements are used to govern the examination and testing of 
snubbers.
Code case N-520-2
    Comment: Tennessee Valley Authority suggested that Code Case N-520-
2, ``Alternative Rules for Renewal of Active or Expired N-type 
Certificates for Plants Not in Active Construction,'' be included in 
the final RG rather than the Code Case N-520-1 which was listed in the 
draft regulatory guide. Case N-520-2 is representative of the current 
nuclear plants for which construction is likely to be renewed.
    NRC Response: The NRC declines at this time to adopt the changes in 
the final guide as suggested by the commenter. The objective of Code 
Case N-520-1 was to address situations where construction on a nuclear 
power plant was halted and thus interrupted ASME Code activities but 
the Certificate Holder maintained their certificate. Code Case N-520-1 
provides guidance on what a Certificate Holder has to do to document 
and stamp the completed construction work that was performed. Code Case 
N-520-2 is different however, in that it addresses the situation where 
the Certificate Holder let its N-type certificates expire.
    The revised Code Case would allow an organization with an expired 
Certificate to secure an ASME Temporary Certificate of Authorization. 
While the NRC recognizes that the temporary certificate would only 
apply in situations where the plant was kept in an appropriate state 
where completion could be restarted at a later date and that the 
temporary certificate would be issued solely for the purpose of 
finishing the documentation and stamping required for the construction 
completed prior to work being stopped, the NRC has determined that the 
public should have an opportunity to comment on this change before a 
final decision is made. Accordingly, Code Case N-520-2 and the 
suggestion provided by the commenter will be discussed in the next 
proposed rule.
    The NRC notes that the wording of Code Case N-520-2 may create 
confusion regarding the relationship between the Authorized Nuclear 
Inspection Agency (ANIA) and the Authorized Nuclear Inspector (ANI). 
Accordingly, it is suggested that the wording of the Code Case be 
modified to clearly indicate that the ``ANIA'' is an Authorized Nuclear 
Inspection Agency and the ANIA employs the ANI.
Code Case N-597-2
    Comment: Two commenters (comments PGE1 and NEI1) suggest that the 
method used to evaluate local degradation for Code Case, N-597-2, 
``Requirements for Analytical Evaluation of Pipe Wall Thinning, Section 
XI, Division 1,'' should be the same as that used in Code Case N-513-2, 
``Evaluation Criteria for Temporary Acceptance of Flaws in Moderate 
Energy Class 2 or 3 Piping, Section XI, Division 1.'' The commenters 
argue that the NRC has conditionally approved Code Case N-513-2 with an 
evaluation methodology to allow licensees to temporarily accept flaws 
in moderate energy Class 2 or 3 piping whereas condition (2) on Code 
Case N-597-2 would require NRC approval for any amount of local 
degradation beyond that calculated by the hoop stress equation.
    The commenters believe that the N-513-2 methodology could be used 
for N-597-2 to eliminate the need for NRC approval in certain 
situations.
    Response: The NRC declines the suggestion to adopt the Code Case N-
513-2 methodology in Code Case N-597-2 in the final guide. It would not 
be appropriate to include such a significant expansion of the scope of 
the Code Case in the final guide without first having sought public 
comment. While the NRC agrees that the flaw evaluation methodology for 
analyzing piping degradation contained in Code Case N-513-2 could under 
certain circumstances be applied for a Code Case N-597-2 evaluation 
(i.e., both Code Cases address the analytical evaluation of pipe wall 
thinning), the NRC disagrees with the commenters that through-wall 
leakage should be included in the scope of such an evaluation.
    Code Case N-597 was not developed to address leakage, (i.e., it is 
focused only on analytical evaluation of wall thinning). The temporary 
acceptance of through-wall leakage is governed by other Code Cases such 
as N-513-2. The addition of leakage as a condition to Code Case N-597 
as suggested would imply that leakage could be justified on a permanent 
basis. In addition, Code Case N-597-2 is applicable to all ASME Code 
Class piping, which would include high energy piping. Code Case N-513-2 
is limited to Class 2 and 3 moderate energy piping. The NRC has only 
approved temporary acceptance of flaws for moderate energy Class 2 or 3 
piping (maximum operating temperature does not exceed 200[deg]F 
(93[deg]C) and maximum operating pressure does not exceed 275 psig (1.9 
MPa). Finally, such a change would redefine the defense-in-depth 
concept.
    Rather than performing inspections to detect flaws before 
structural integrity is compromised, degradation would in effect be 
managed after leakage is discovered. Thus, no changes have been made in 
the final guide as a result of the comments.
Code Case N-619, Code Case N-648-1
    Comment: One commenter (number 7) requests that the NRC reconsider 
the conditions placed on Code Case N-619, ``Alternative Requirements 
for Nozzle Inner Radius Inspections for Class 1 Pressurizer and Steam 
Generator Nozzles, Section XI, Division 1,'' and Code Case N-648-1, 
``Alternative Requirements for Inner Radius Examination of Class 1 
Reactor Pressure Vessel Nozzles, Section XI, Division 1.''

[[Page 61329]]

The commenter believes that the conditions on the two Code Cases 
requiring a wire standard to demonstrate the resolution capability of 
remote visual examination systems should be changed to the ASME 0.044 
inch characters because characters have been recognized to be a better 
resolution standard (comment CW1). The commenter also raised a question 
regarding the use of Section XI Table IWB-3512-1 (comment CW2). The 
condition on Code Case N-619 state that licensees may perform a visual 
examination utilizing the allowable flaw length criteria of Table IWB-
3512-1. The commenter believes it is unclear how allowable flaw lengths 
can be determined from Table IWB-3512-1. The commenter suggested that 
the same acceptance criteria approved by the NRC for Code Case N-648-1 
be applied to Code Case N-619 since both Code Cases address the 
examination of the inner nozzle radius. Finally, the commenter believes 
that the condition on Code Case N-648-1 addressing the examination 
volume can be deleted as it describes the same volume required to be 
examined by the Code Case (comment CW3).
    Response: The NRC declines at this time to adopt the changes in the 
final guide as suggested by the commenter. It would not be appropriate 
to adopt significant changes to visual testing resolutions standards in 
the final guide without first having sought public comment.
    The NRC agrees that characters have been demonstrated to be a 
better resolution standard than the 1-mil wire standard. However, the 
NRC cannot at this time support modifying the criteria in the RG on 
these Code Cases to change to the ASME 0.044 inch characters as 
suggested. While the NRC staff ultimately supports the replacement of 
the wire resolution standard, the staff believes that the shift to 
characters should be part of broader changes to the visual testing 
provisions as related to Code Cases N-619 and N-648-1.
    Visual examinations are used in certain situations as alternatives 
to volumetric and/or surface examination tests where it is not possible 
to conduct volumetric examination (e.g., where there are limitations 
due to access or geometry) or to reduce occupational exposure in high 
radiation fields. Visual testing experts believe that if the camera and 
lighting were sufficient to resolve a 12 [mu]m (0.0005 in.) diameter 
wire, then the camera system had a resolution sufficiently high for the 
inspection. Subsequent investigation of the effectiveness and 
reliability of visual examinations has shown that the wire resolution 
standard is not sufficient to determine the visual acuity of a remote 
system, (i.e., there are important differences between visually 
detecting a wire and a crack). Research conducted at the Pacific 
Northwest National Laboratory (PNNL) showed that other calibration 
standards be adapted for visual testing such as reading charts and 
resolution targets. Results supporting this recommendation were 
published in NUREG/CR-6943, ``A Study of Remote Visual Methods to 
Detect Cracking in Reactor Components.''
    However, as also discussed in the reports, other parameters such as 
crack size, lighting conditions, camera resolution, and surface 
conditions were assessed. The NRC concluded from the investigation that 
a significant fraction of the cracks that have been reported in nuclear 
power plant components are at the lower end of the capabilities of the 
visual testing equipment currently being used. Code Case N-619 
addresses the examination of the nozzle inner radius of Class 1 
pressurizers and steam generators.
    Code Case N-648-1 provides an alternative for examining the inner 
radius of Class 1 reactor vessel nozzles. The NRC investigation of 
crack opening dimensions of service-induced cracks in nuclear 
components included thermal fatigue, mechanical fatigue, and stress 
corrosion cracks. The NRC concluded that current visual testing systems 
may not reliably detect a significant number of these cracks 
(approaching 50% under certain conditions). Research at PNNL showed 
that detection of these cracks under field conditions is strongly 
dependent on camera magnification, lighting, inspector training, and 
inspector vigilance.
    While this research supports the use of characters in lieu of a 
wire standard, the research also shows that other changes are warranted 
to visual testing as related to these two Code Cases. The NRC believes 
that such significant changes to visual testing criteria should be 
undertaken by the ASME and industry in a coordinated manner.
    With regard to comment CW2 that it is unclear how allowable flaw 
lengths can be determined from Table IWB-3512-1, the NRC agrees that 
the condition to determine allowable flaw length criteria could be 
improved, and public comments will be specifically sought on Code Case 
N-619 in the next proposed rule on this issue.
    Finally, it is agreed that the condition requiring the examination 
of the surface between points M and N is unnecessary because Code Case 
N-648-1 already requires this examination. However, the NRC will have 
to request public comment on Code Case N-648-1 regarding this issue in 
the next proposed rule.
Code Cases N-655-1, N-757-1, N-759-1, N-782
    Comment: Westinghouse Electric Company (comments WECRS1 and 
WECJAG1) identified four Code Cases used in the AP1000 design that were 
not included in the draft of RG 1.84. The commenter suggested that the 
Code Cases be included in the next revision of RG1.84, (i.e., Code Case 
N-655-1, ``Use of SA-738, Grade B, for Metal Containment Vessels, Class 
MC, Section III, Division 1),'' Code Case N-757-1, ``Alternative Rules 
for Acceptability for Class 2 and 3 Valves, NPS 1 (DN25) and Smaller 
with Welded and Nonwelded End Connections other than Flanges, Section 
III, Division 1,'' Code Case N-759-2, ``Alternative Rules for 
Determining Allowable External Pressure and Compressive Stresses for 
Cylinders, Cones, Spheres, and Formed Heads, Section III, Division 1,'' 
and Code Case N-782, ``Use of Code Editions, Addenda, and Cases Section 
III, Division 1.''
    Response: The NRC does not agree that these Code Cases should be 
included in the final RG. The Code Cases referenced in the comment are 
not currently listed in the latest AP1000 Design Control Document 
(DCD). In addition, public comment has not yet been sought on these 
Code Cases. Accordingly, the NRC will consider including Code Cases N-
655-1, N-757-1, N-759-2, and N-782 in the next draft RG (DG-1230; 
proposed Revision 36 to RG 1.84), which is currently under development. 
If Westinghouse includes the above ASME Code Cases in its next revision 
to the AP1000 DCD, then the NRC staff will provide an evaluation of the 
acceptability of using these four ASME Code Cases in a supplement to 
its Final Safety Evaluation Report for the AP1000 design certification 
amendment as alternatives to the regulations under Sec.  50.55a(a)(3).
    For the reasons set forth above, the NRC declines to adopt the 
comment and no change was made to the RG as the result of this comment.
Code Case N-702
    Comment: Two commenters (comments ASME8 and TVA2) request that Code 
Case N-702, ``Alternative Requirements for Boiling Water Reactor (BWR) 
Nozzle Inner Radius and Nozzle-to-Shell Welds, Section XI, Division 
1,'' be conditionally accepted in the final RG. The NRC approved use of 
the Code Case with certain criteria in a Safety Evaluation of BWRVIP-
108: BWR

[[Page 61330]]

Vessel and Internals Project, Technical Basis for the Reduction of 
Inspection Requirements for the Boiling Water Reactor Nozzle-to-Vessel 
Shell Welds and Nozzle Blend Radii,'' EPRI Technical Report 1003557, 
October 2002 (ADAMS Accession No. ML023330203). The commenters believe 
that these criteria provide a basis for the NRC to conditionally 
approve the Code Case in RG 1.147.
    Response: The NRC declines at this time to adopt the changes in the 
final guide as suggested by the commenter. It would not be appropriate 
to generically adopt the alternative nozzle examination requirements 
without first having sought public comment on this Code Case. The NRC 
agrees, however, that the NRC staff's Safety Evaluation (dated December 
18, 2007, ADAMS Accession No. ML073600374) provides a basis for 
approving Code Case N-702 in RG 1.47. Code Case N-702 will be addressed 
the next draft guide.
Code Case N-747
    Comment: The American Society of Mechanical Engineers (comment 
ASME9) believes that the basis for listing Code Case N-747, ``Reactor 
Vessel Head-to Flange Weld Examinations, Section XI, Division 1,'' in 
DG-1193 (Code Cases not approved for use) was flawed, and the Code Case 
should be unconditionally accepted in final Revision 16 of RG 1.147.
    Response: The NRC declines at this time to adopt the changes in the 
final guide as suggested by the commenter. It would not be appropriate 
to adopt the Code Case in the final guide without first having sought 
public comment. Nonetheless, the NRC staff has reviewed the additional 
information provided by the ASME regarding the expected fluence levels 
of reactor vessel head-to-flange welds and believes that an adequate 
technical basis has been provided to support a conclusion that the 
fracture toughness will remain high. Code Case N-747 will be addressed 
in the next draft guide.

Code Case With Proposed Conditions--No Public Comments

    In the proposed rule, the NRC proposed to condition Code Case N-
570-1. No public comments were received on the proposed conditions to 
the Code Case. Thus, no changes have been made to the proposed adoption 
of Code Case N-570-1.

Section III

    Code Case N-570-1, Alternative Rules for Linear Piping and Linear 
Standard Supports for Classes 1, 2, 3, and [Metal Cladding (MC)], 
Section III, Division 1. Code Case N-570-1 references American National 
Standards Institute (ANSI)/American Institute of Steel Construction 
(AISC) N690-1994 s1, ``Supplement No. 1 to the Specification for the 
Design, Fabrication, and Erection of Steel Safety-Related Structures 
for Nuclear Facilities.'' However, the AISC issued Supplement 2 on 
October 6, 2004. Supplement 2 supersedes Supplement 1. The updated 
supplement (Supplement 2) is consistent with NRC positions and 
requirements for new reactor support design. Thus, the NRC is 
conditioning Code Case N-570-1 to require that ANSI/AISC N690-1994 s2, 
``Supplement No. 2 to the Specification for the Design, Fabrication, 
and Erection of Steel Safety-Related Structures for Nuclear 
Facilities,'' be used when this code case is implemented.

III. NRC Approval of New and Amended ASME Code Cases

    This final rule incorporates by reference the latest revisions of 
the NRC RGs that list acceptable and conditionally acceptable ASME BPV 
Code Cases. RG 1.84, Revision 35 would supersede Revision 34 (October 
2007); and RG 1.147, Revision 16 would supersede Revision 15 (October 
2007). RG 1.192 (June 2003) would not be revised because there have 
been no new OM Code Cases published by the ASME since the last NRC 
review.
    The ASME Code Cases which are the subject of this rulemaking are 
the new revised Section III and Section XI Code Cases listed in 
Supplements 2 through 11 to the 2004 BPV Code, and Supplement 0 
published with the 2007 Edition of the BPV Code (Supplement 0 also 
serves as Supplement 12 to the 2004 Edition) of the code. The NRC 
followed a three-step process to determine acceptability of new and 
revised ASME Code Cases and the need for conditions on the uses of 
these Code Cases. This process was employed in the review of the ASME 
Code Cases which are the subject of this final rule. First, NRC staff 
actively participated with other ASME committee members with full 
involvement in discussions and technical debates in the development of 
new and revised Code Cases. This included a technical justification in 
support of each new or revised Code Case. Second, the NRC committee 
representatives distributed the Code Case and technical justification 
to other cognizant NRC staff to ensure an adequate technical review.
    Finally, the proposed NRC position on each Code Case is reviewed 
and approved by NRC management as part of the rulemaking amending 10 
CFR 50.55a to incorporate by reference new revisions of the RGs listing 
the relevant ASME Code Cases and conditions on their use. This 
regulatory process, when considered together with the ASME's own 
process for development and approval of ASME Code Cases, provides 
reasonable assurances that the NRC approves for use only those new and 
revised ASME Code Cases (with conditions as necessary) which provide 
reasonable assurance of adequate protection to public health and safety 
and which do not have significant adverse impacts on the environment.

Code Cases Approved Unconditionally for Use

    The NRC concludes, in accordance with the process for review of 
ASME Code Cases, that each of the ASME Code Cases listed in Table 1 is 
technically adequate and consistent with current NRC regulations.

              Table 1--Unconditionally Approved Code Cases
------------------------------------------------------------------------
         Code Case No.           Code supplement      Code case title
------------------------------------------------------------------------
                       ASME B&PV Code, Section III
------------------------------------------------------------------------
N-4-12........................  4................  Special Type 403
                                                    Modified Forgings or
                                                    Bars, Class and CS,
                                                    Section III,
                                                    Division 1.
N-284-2.......................  12...............  Metal Containment
                                                    Shell Buckling
                                                    Design Methods,
                                                    Class MC, Section
                                                    III, Division 1.
N-373-3.......................  3................  Alternative postweld
                                                    heat treatment
                                                    (PWHT) Time at
                                                    Temperature for P-
                                                    No. 5A or P-No. 5B
                                                    Group 1 Material,
                                                    Classes 1, 2, and 3
                                                    Section III,
                                                    Division 1.
N-621-1.......................  3................  Ni-Cr-Mo Alloy
                                                    Unified Numbering
                                                    System (UNS) N06022)
                                                    Weld Construction to
                                                    800[deg]F, Section
                                                    III, Division 1.

[[Page 61331]]

 
N-699.........................  8................  Use of Titanium Grade
                                                    2 (UNS R50400) Tube
                                                    and Bar, and Grade 1
                                                    (UNS R50250) Plate
                                                    and Sheet for Class
                                                    1 Construction,
                                                    Section III,
                                                    Division 1.
N-725.........................  4................  Design Stress Values
                                                    for UNS N06690 With
                                                    Minimum Specified
                                                    Yield Strength of 35
                                                    Ksi (240 Mpa),
                                                    Classes 2 and 3
                                                    Components, Section
                                                    III, Division 1.
N-727.........................  9................  Dissimilar Welding
                                                    Using Continuous
                                                    Drive Friction
                                                    Welding for Reactor
                                                    Vessel Control Rod
                                                    Drive Mechanism
                                                    (CRDM)/Control
                                                    Element Drive
                                                    Mechanism
                                                    (CEDM)Nozzle to
                                                    Flange/Adapter
                                                    Welds, Class 1,
                                                    Section III,
                                                    Division 1.
N-732.........................  5................  Magnetic Particle
                                                    Examination of
                                                    Forgings for
                                                    Construction,
                                                    Section III,
                                                    Division 1.
N-736.........................  8................  Use UNS S32050 Welded
                                                    and Seamless Pipe
                                                    and Tubing,
                                                    Forgings, and Plates
                                                    Conforming to SA-249/
                                                    SA-249M, SA-479/SA-
                                                    479M, and SA-240/SA-
                                                    240M, and Grade
                                                    CK35MN Castings
                                                    Conforming to ASTM A
                                                    743-03 for
                                                    Construction of
                                                    Class 1, 2, and 3
                                                    Components, Section
                                                    III, Division 1.
N-738.........................  6................  NDE of Full
                                                    Penetration Butt
                                                    Welds in Class 2
                                                    Supports, Section
                                                    III, Division 1.
N-741.........................  7................  Use of 22Cr-5Ni-3Mo-N
                                                    (Alloy UNS S32205
                                                    Austenitic/Ferritic
                                                    Duplex Stainless
                                                    Steel) Forgings,
                                                    Plate, Welded and
                                                    Seamless Pipe
                                                    Tubing, and Fittings
                                                    to SA-182, SA-240,
                                                    SA-789, A 790-04a,
                                                    SA-815, Classes 2
                                                    and 3, Section III,
                                                    Division 1.
N-744.........................  11...............  Use of Metric Units
                                                    Boiler and Pressure
                                                    Vessel Code, Section
                                                    III, Division 1.
N-746.........................  8................  Use of 46Fe-24Ni-21Cr-
                                                    6Mo-Cu-N (UNS
                                                    N08367) Bolting
                                                    Materials for Class
                                                    2 and 3 Components,
                                                    Section III,
                                                    Division 1.
N-756.........................  12...............  Alternative Rules for
                                                    Acceptability for
                                                    Class 1 Valves, NPS
                                                    (DN 25) and Smaller
                                                    with Nonwelded End
                                                    Connections Other
                                                    than Flanges,
                                                    Section III,
                                                    Division 1.
N-759.........................  11...............  Alternative Rules for
                                                    Determining
                                                    Allowable External
                                                    Pressure and
                                                    Compressive Stresses
                                                    for Cylinders,
                                                    Cones, Spheres, and
                                                    Formed Heads,
                                                    Section III,
                                                    Division 1.
------------------------------------------------------------------------
                       ASME B&PV Code, Section XI
------------------------------------------------------------------------
N-494-4.......................  7................  Pipe Specific
                                                    Evaluation
                                                    Procedures and
                                                    Acceptance Criteria
                                                    for Flaws in Piping
                                                    that Exceed the
                                                    Acceptance
                                                    Standards, Section
                                                    XI, Division 1.
N-496-2.......................  2................  Helical-Coil Threaded
                                                    Inserts, Section XI,
                                                    Division 1.
N-666.........................  9................  Weld Overlay of Class
                                                    1, 2, and 3 Socket
                                                    Welded Connections,
                                                    Section XI, Division
                                                    1.
N-686-1.......................  12...............  Alternative
                                                    Requirements for
                                                    Visual Examinations
                                                    VT-1, VT-2, and VT-
                                                    3, Section XI,
                                                    Division 1.
N-705.........................  11...............  Evaluation Criteria
                                                    for Temporary
                                                    Acceptance of
                                                    Degradation in
                                                    Moderate Energy
                                                    Class 2 or 3 Vessels
                                                    and Tanks, Section
                                                    XI, Division 1.
N-706-1.......................  12...............  Alternative
                                                    Examination
                                                    Requirements of
                                                    Table IWB-2500-1 and
                                                    Table IWC-2500-1 for
                                                    Pressurized Water
                                                    Reactor (PWR)
                                                    Stainless Steel
                                                    Residual and
                                                    Regenerative Heat
                                                    Exchangers, Section
                                                    XI, Division 1.
N-712.........................  2................  Class 1 Socket Weld
                                                    Examinations,
                                                    Section XI, Division
                                                    1.
N-730.........................  11...............  Roll Expansion of
                                                    Class 1 Control Rod
                                                    Drive Bottom Head
                                                    Penetrations in
                                                    Boiling Water
                                                    Reactors (BWR),
                                                    Section XI, Division
                                                    1.
N-731.........................  5................  Alternative Class 1
                                                    System Leakage Test
                                                    Pressure
                                                    Requirements,
                                                    Section XI, Division
                                                    1.
N-733.........................  6................  Mitigation of Flaws
                                                    in NPS 2 (DN 50) and
                                                    Smaller Nozzles and
                                                    Nozzle Partial
                                                    Penetration Welds in
                                                    Vessels and Piping
                                                    by Use of a
                                                    Mechanical
                                                    Connection
                                                    Modification,
                                                    Section XI, Division
                                                    1.
N-735.........................  11...............  Successive Inspection
                                                    of Class 1 and 2
                                                    Piping Welds,
                                                    Section XI, Division
                                                    1.
N-739.........................  11...............  Alternative
                                                    Qualification
                                                    Requirements for
                                                    Personnel Performing
                                                    Class CC Concrete
                                                    and Post-tensioning
                                                    System Visual
                                                    Examinations,
                                                    Section XI, Division
                                                    1.
N-753.........................  10...............  Vision Tests, Section
                                                    XI, Division 1.
------------------------------------------------------------------------

Code Cases Approved for Use With Conditions
---------------------------------------------------------------------------

    \2\ The NRC reviews every Code Case to ascertain if each of the 
Code Cases is technically adequate and consistent with current NRC 
regulations. As a result of such reviews, the NRC may conclude that 
certain Code Cases are technically adequate or require supplemental 
guidance. In such cases, the NRC imposes limitations, modifications, 
and provisions on those Code Cases but is now substituting the word 
``Conditions'' throughout 10 CFR 50.55a.
---------------------------------------------------------------------------

    As a result of the NRC staff's review, the NRC concludes that 
certain Code Cases are technically inadequate or require supplemental 
guidance. Accordingly, the NRC is imposing conditions \2\ upon the use 
of these Code Cases, and they are listed in Table 2.

[[Page 61332]]



                                   Table 2--Conditionally Approved Code Cases
----------------------------------------------------------------------------------------------------------------
        Code Case No.               Code supplement           Code case title                Condition
----------------------------------------------------------------------------------------------------------------
                                           ASME B&PV Code, Section III
----------------------------------------------------------------------------------------------------------------
N-71-18......................  Revision 18 of the Code   Additional Materials for  (1) The maximum measured
                                Case was not new to       Subsection NF, Class 1,   ultimate tensile strength
                                Draft Revision 35 of      2, 3, and MC Component    (UTS) of the component
                                Regulatory Guide 1.84.    Supports Fabricated by    support material must not
                                The Code Case is listed   Welding, Section III,     exceed 170 Ksi in view of
                                in this table because a   Division 1.               the susceptibility of high-
                                public comment was                                  strength materials to
                                received suggesting                                 brittleness and stress
                                editorial corrections.                              corrosion cracking.
                                                                                   (2) Certain applications may
                                                                                    exist where a UTS value of
                                                                                    up to 190 Ksi could be
                                                                                    considered acceptable for a
                                                                                    material and, under this
                                                                                    condition, the Design
                                                                                    Specification must specify
                                                                                    impact testing for the
                                                                                    material. For these cases,
                                                                                    it must be demonstrated by
                                                                                    the applicant that:
                                                                                      (a) The impact test
                                                                                       results for the material
                                                                                       meet Code requirements,
                                                                                      (b) The material is not
                                                                                       subject to stress
                                                                                       corrosion cracking by
                                                                                       virtue of the fact that:
                                                                                        (i) A corrosive
                                                                                         environment is not
                                                                                         present, and
                                                                                        (ii) The component that
                                                                                         contains the material
                                                                                         has essentially no
                                                                                         residual stresses or
                                                                                         assembly stresses, and
                                                                                        (iii) It does not
                                                                                         experience frequent
                                                                                         sustained loads in
                                                                                         service.
                                                                                   (3) In the last sentence of
                                                                                    paragraph 4.2, reference
                                                                                    must be made to paragraph
                                                                                    4.5.2.2, ``Alternative
                                                                                    Atmosphere Exposure Time
                                                                                    Periods Established by
                                                                                    Test,'' of the AWS D1.1 Code
                                                                                    for the evidence presented
                                                                                    to and accepted by the
                                                                                    Authorized Inspector
                                                                                    concerning exposure of
                                                                                    electrodes for longer
                                                                                    periods of time.
                                                                                   (4) Paragraph 15.2.2 is not
                                                                                    acceptable as written and
                                                                                    must be replaced with the
                                                                                    following: ``When not
                                                                                    exempted by 15.2.1 above,
                                                                                    the post-weld heat treatment
                                                                                    must be performed in
                                                                                    accordance with NF-4622
                                                                                    except that ASTM A-710 Grade
                                                                                    A Material must be at least
                                                                                    1,000 [deg]F (540 [deg]C)
                                                                                    and must not exceed 1,150
                                                                                    [deg]F (620 [deg]C) for
                                                                                    Class 1 and Class 2 material
                                                                                    and 1,175 [deg]F (640
                                                                                    [deg]C) for Class 3
                                                                                    material.
                                                                                   (5) The new holding time at
                                                                                    temperature for weld
                                                                                    thickness (nominal) must be
                                                                                    30 minutes for \1/2\ inch or
                                                                                    less, 1 hour per inch for
                                                                                    thickness over \1/2\ inch to
                                                                                    5 inches, and for
                                                                                    thicknesses over 5 inches, 5
                                                                                    hours plus 15 minutes for
                                                                                    each additional inch over 5
                                                                                    inches.
                                                                                   (6) The fracture toughness
                                                                                    requirements as listed in
                                                                                    this Code Case apply only to
                                                                                    piping supports and not to
                                                                                    Class 1, Class 2, and Class
                                                                                    3 component supports.
N-570-1......................  8.......................  Alternative Rules for     The provisions of ANSI/AISC
                                                          Linear Piping and         N690-1994 s2, ``Supplement
                                                          Linear Standard           No. 2 to the Specification
                                                          Supports for Classes 1,   for the Design, Fabrication,
                                                          2, 3, and MC, Section     and Erection of Steel of
                                                          III, Division 1.          Safety-Related Structures
                                                                                    for Nuclear Facilities,''
                                                                                    must be met.
----------------------------------------------------------------------------------------------------------------
                                           ASME B&PV Code, Section XI
----------------------------------------------------------------------------------------------------------------
N-416-4......................  4.......................  Alternative Pressure      Nondestructive examination
                                                          Test Requirement for      shall be performed on welded
                                                          Welded or Brazed          or brazed repairs and
                                                          Repairs, Fabrication      fabrication and installation
                                                          Welds or Brazed Joints    joints in accordance with
                                                          for Replacement Parts     the methods and acceptance
                                                          and Piping                criteria of the applicable
                                                          Subassemblies, or         subsection of the 1992
                                                          Installation of           Edition of Section III.
                                                          Replacement Items by
                                                          Welding or Brazing,
                                                          Classes 1, 2, and 3,
                                                          Section XI, Division 1.
N-504-4......................  10......................  Alternative Rules for     The provisions of Section XI,
                                                          Repair of Class 1, 2,     Nonmandatory Appendix Q,
                                                          and 3 Austenitic          ``Weld Overlay Repair of
                                                          Stainless Steel Piping,   Class 1, 2, and 3 Austenitic
                                                          Section XI, Division 1.   Stainless Steel Piping
                                                                                    Weldments,'' must also be
                                                                                    met. In addition, the
                                                                                    following conditions shall
                                                                                    be met: (a) The total
                                                                                    laminar flaw area shall not
                                                                                    exceed 10 percent of the
                                                                                    weld surface area, and no
                                                                                    linear dimension of the
                                                                                    laminar flaw area shall
                                                                                    exceed the greater of 3
                                                                                    inches or 10 percent of the
                                                                                    pipe circumference; and (b)
                                                                                    radiography shall not be
                                                                                    used to detect planar flaws
                                                                                    under or masked by laminar
                                                                                    flaws.

[[Page 61333]]

 
N-638-4......................  11......................  Similar and Dissimilar    Ultrasonic examination shall
                                                          Metal Welding Using       be demonstrated for the
                                                          Ambient Temperature       repaired volume using
                                                          Machine GTAW Temper       representative samples which
                                                          Bead Technique, Section   contain construction type
                                                          XI, Division 1.           flaws.
N-661-1......................  7.......................  Alternative Requirements  (1) If the cause of the
                                                          for Wall Thickness        degradation has not been
                                                          Restoration of Class 2    determined, the repair is
                                                          and 3 Carbon Steel        only acceptable until the
                                                          Piping for Raw Water      next refueling outage.
                                                          Service, Section XI,     (2) When through-wall repairs
                                                          Division 1.               are made by welding on
                                                                                    surfaces that are wet or
                                                                                    exposed to water, the weld
                                                                                    overlay repair is only
                                                                                    acceptable until the next
                                                                                    refueling outage.
N-751........................  11......................  Pressure Testing of       When a 10 CFR Part 50,
                                                          Containment Penetration   Appendix J, Type C test is
                                                          Piping, Section XI,       performed as an alternative
                                                          Division 1.               to the requirements of IWA-
                                                                                    4540 (IWA-4700 in the 1989
                                                                                    edition through the 1995
                                                                                    edition) during repair and
                                                                                    replacement activities,
                                                                                    nondestructive examination
                                                                                    must be performed in
                                                                                    accordance with IWA-
                                                                                    4540(a)(2) of the 2002
                                                                                    Addenda of Section XI.
----------------------------------------------------------------------------------------------------------------

ASME Code Cases Not Approved for Use

    ASME Code Cases which 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. The Code Cases which are not approved for 
use include Code Cases on high-temperature gas cooled reactors; certain 
requirements in Section III, Division 2, that are not endorsed by the 
NRC; liquid metal; and submerged spent fuel waste casks. RG 1.193 is 
not incorporated by reference into Sec.  50.55a. The RG is prepared by 
the NRC as a resource for stakeholders, allowing them to easily 
identify Code Cases which the NRC has not approved for use as a generic 
matter. Listing of a Code Case in RG 1.193 does not preclude an 
applicant or licensee from seeking individual, case-by-case NRC 
approval to use a listed Code Case.

IV. Paragraph-By Paragraph Discussion

Overall Considerations on the Use of ASME Code Cases

    This final rule amends 10 CFR 50.55a to incorporate by reference RG 
1.84, Revision 35, which supersedes Revision 34, and RG 1.147, Revision 
16, which supersedes Revision 15. The following general guidance 
applies to the use of the ASME Code Cases approved in the latest 
versions of the regulatory guides which are incorporated by reference 
into 10 CFR 50.55a as part of this rulemaking.
    The endorsement of a Code Case in NRC RGs constitutes acceptance of 
its technical position for applications which are not precluded by 
regulatory or other requirements or by the recommendations in these or 
other RGs. The applicant and licensee are responsible for ensuring that 
use of the Code Case does not conflict with regulatory requirements or 
licensee commitments. The Code Cases listed in the RGs are acceptable 
for use within the limits specified in the Code Case. If the RG states 
an NRC condition on the use of a Code Case, then the NRC condition 
supplements and does not supersede any condition(s) specified in the 
code case, unless otherwise stated in the NRC condition.
    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, 10 CFR 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 application unless otherwise 
indicated.
    Section III of the ASME BPV Code applies only to new designs and 
construction of new plants. The edition and addenda to be used in the 
design and/or construction of a plant are selected based on the date of 
the construction permit, combined license, design certification, or 
manufacturing license and are not changed thereafter, except 
voluntarily by the applicant or the licensee (unless prohibited by 
applicable NRC finality provisions in 10 CFR Part 52) or as otherwise 
permitted under 10 CFR Part 52). 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 10 CFR 50.55a and listed in 
the RGs, then 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).
    The ISI and OM IST programs for a 10 CFR Part 50 operating license 
or 10 CFR Part 52 combined license 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 to 10 CFR 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. Because Code Cases apply to specific editions and addenda and 
because Code Cases may be revised because they are no longer accurate 
or adequate, licensees choosing to continue using a Code Case during 
the subsequent ISI 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 or expired, the applicant or the 
licensee may continue to use the Code Case until the applicant or the

[[Page 61334]]

licensee updates its construction Code of Record (in the case of an 
applicant, updates its application) or until the licensee's 120-month 
ISI/IST update interval expires, after which the continued use of the 
code case is prohibited unless NRC approval is granted under Sec.  
50.55a(a)(3). 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 effective date of the final rulemaking. 
Concurrent with this action, the NRC is publishing in the Federal 
Register Notices of availability of these RGs listing acceptable ASME 
BPV Code Cases.

Section 50.55a(b)

    In paragraphs (b) and (b)(4) of Sec.  50.55a, the reference to the 
revision number for RG 1.84 is changed from ``Revision 34'' to 
``Revision 35.'' In paragraph (b)(5) of Sec.  50.55a, the reference to 
the revision number for RG 1.147 is changed from ``Revision 15'' to 
``Revision 16.''

Sections 50.55a(f)(2), (f)(3)(iii)(A), (f)(3)(iv)(A), (f)(4)(ii), 
(g)(2), (g)(3)(i), (g)(3)(ii), (g)(4)(i), and (g)(4)(ii)

    In paragraphs (f)(2), (f)(3)(iii)(A), (f)(3)(iv)(A), (f)(4)(ii), 
(g)(2), (g)(3)(i), (g)(3)(ii), (g)(4)(i), and (g)(4)(ii) of Sec.  
50.55a, the reference to the revision number for RG 1.147 is changed 
from ``Revision 15'' to ``Revision 16.''

V. Availability of Documents

    The NRC is making the documents identified below available to 
interested persons through one or more of the following:
    Public Document Room (PDR): The NRC PDR is located at 11555 
Rockville Pike, Public File Area O-1F21, Rockville, Maryland 20852.
    Federal Rulemaking Web Site: Public comments and supporting 
material related to this final rule can be found at http://regulations.gov by searching on the Docket ID NRC-2009-0014.
    The NRC's Public Electronic Reading Room:
    The NRC's public electronic reading room is located at http://www.nrc.gov/reading-rm.html.

                                                     Table 2
----------------------------------------------------------------------------------------------------------------
                   Document                         PDR           Web                  e-Reading Room
----------------------------------------------------------------------------------------------------------------
Final Rule Regulatory Analysis...............            X             X   ML100560131
RG 1.84, Revision 35.........................            X             X   ML101800532
RG 1.147, Revision 16........................            X             X   ML101800536
RG 1.193, Revision 3.........................            X             X   ML101800540
Public Comments..............................            X             X   ML100670356
Safety Evaluation Report EPRI Report (BWRVIP-            X             X   ML073600374
 108) (December 18, 2007) BWR Nozzle-to-
 Vessel Welds and Nozzle Inner Radius.
----------------------------------------------------------------------------------------------------------------

VI. Voluntary Consensus Standards

    The National Technology Transfer and Advancement Act of 1995, 
Public Law (Pub. L.) 104-113, requires Federal agencies to use 
technical standards developed or adopted by voluntary consensus 
standards bodies unless the use of such standards is inconsistent with 
applicable law or is otherwise impractical. In this action, the NRC is 
amending its regulations to incorporate by reference RGs that list ASME 
BPV Code Cases approved by the NRC. ASME Code Cases, which are ASME-
approved alternatives to the provisions of ASME Code editions and 
addenda, are developed by the ASME whose members (including the NRC and 
utilities) have broad and varied interests. Therefore, ASME Code Cases 
are national consensus standards as defined in Pub. L. 104-113 and OMB 
Circular A-119.
    The NRC reviews each Section III and Section XI Code Case published 
by the ASME to ascertain whether it is consistent with the safe 
operation of nuclear power plants. Those code cases found to be 
acceptable are listed in the RGs that are incorporated by reference in 
Sec.  50.55a(b). Those that are found to be unacceptable are listed in 
RG 1.193, but licensees may still seek NRC's approval to apply these 
Code Cases through the relief request process permitted in Sec.  
50.55a(a)(3). Other Code Cases, which the NRC finds to be conditionally 
acceptable, are also listed in the RGs that are incorporated by 
reference along with the conditions under which they may be applied. If 
the NRC did not conditionally accept ASME Code Cases, it would 
disapprove these Code Cases entirely. The effect would be that 
licensees would need to submit a larger number of relief requests, 
which would be an unnecessary additional burden for both the licensee 
and the NRC. For these reasons, the treatment of ASME BPV and OM Code 
Cases and any conditions placed on them in this final rule does not 
conflict with any policy on agency use of consensus standards specified 
in OMB Circular A-119.
    The NRC is aware of other voluntary consensus standards that exist 
in other countries that generally address the subjects covered by the 
ASME Codes and Code Cases. However, the ASME Code is itself recognized 
internationally. The adoption of those other voluntary consensus 
standards would not materially advance the underlying objectives of the 
NTTAA. Accordingly, the NRC is incorporating by reference and approving 
the use the ASME Code Cases, instead of incorporating by reference and 
approving the use of other countries voluntary consensus standards that 
address nuclear power plant piping design, construction, maintenance 
and in-service inspection.

VII. Finding of No Significant Environmental Impact: Environmental 
Assessment

    This final rule action stems from the Commission's practice of 
incorporating by reference the RGs listing the most recent set of NRC-
approved ASME Code Cases. The purpose of this action is to allow 
licensees to use the Code Cases listed in the RGs as alternatives to 
requirements in the ASME BPV Code for the construction and ISI of 
nuclear power plant components. This action is intended to advance the 
NRC's strategic goal of ensuring adequate protection of public health 
and safety and the environment. It also demonstrates the agency's 
commitment to participate in the national consensus standards process 
under the National Technology Transfer and Advancement Act of 1995, 
Pub. L. 104-113.

[[Page 61335]]

    The National Environmental Policy Act (NEPA) requires Federal 
government agencies to study the impacts of their ``major Federal 
actions significantly affecting the quality of the human environment'' 
and prepare detailed statements on the environmental impacts of the 
action and alternatives to the action (United States Code, Vol. 42, 
Section 4332(C) [42 U.S.C. Sec. 4332(C)]; NEPA Sec. 102(C).
    The Commission has determined under NEPA, as amended, and the 
Commission's regulations in Subpart A of 10 CFR Part 51 that this final 
rule would not be a major Federal action significantly affecting the 
quality of the human environment. Therefore, an environmental impact 
statement is not required.
    As alternatives to the ASME Code, NRC-approved Code Cases provide 
an adequate level of safety. Also, use of NRC-approved Code Cases does 
not change the probability or consequences of accidents compared to the 
usage of ASME Code Cases. 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.

VIII. Paperwork Reduction Act Statement

    This final rule increases the burden on licensees applying ASME 
Code Case N-730 to maintain repair records of the current control dive 
bottom head penetrations in BWRs for the life of the reactor vessel (10 
CFR 50.55a). The public burden for the information collection 
associated with Code Case N-730 is estimated to average 5 hours per 
request. In addition, the adoption of ASME Code Cases will result in 
fewer relief requests, a burden hour savings of 20 hours per request. 
Because the burden for the information collections in this rule is 
insignificant, Office of Management and Budget (OMB) clearance is not 
required. Existing requirements were approved by OMB, approval number 
3150-0011.
    Send comments on any aspect of these information collections to the 
Information Services Branch (T-5 F52), U.S. Nuclear Regulatory 
Commission, Washington, DC 20555-0001, or by Internet electronic mail 
to [email protected] and to the Desk Officer, Ms. Christine 
Kymn, Office of Information and Regulatory Affairs, NEOB-10202 (3150-
0011), Office of Management and Budget, Washington, DC 20503.

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 
unless the requesting document displays a currently valid OMB control 
number.

IX. Regulatory Analysis

    The ASME Code Cases listed in the RGs to be incorporated by 
reference provide voluntary alternatives to the provisions in the ASME 
BPV Code for design, construction, and ISI of specific structures, 
systems, and components used in nuclear power plants. Implementation of 
these Code Cases is not required. Licensees use NRC-approved ASME Code 
Cases to reduce unnecessary regulatory burden or gain additional 
operational flexibility. It would be difficult for the NRC to provide 
these advantages independently of the ASME Code Case publication 
process without expending considerable additional resources.
    The NRC has prepared a regulatory analysis addressing the 
qualitative benefits of the alternatives considered in this proposed 
rulemaking and comparing the costs associated with each alternative. 
The regulatory analysis is available to the public as indicated under 
the ``Availability of Documents'' Portion of this document.

X. Regulatory Flexibility Certification

    Under the Regulatory Flexibility Act of 1980 (5 U.S.C. 605(b)), the 
Commission certifies that this final rule would not impose a 
significant economical impact on a substantial number of small 
entities. This final rule would affect only the licensing and operation 
of nuclear power plants. The companies that own these plants are not 
``small entities'' as defined in the Regulatory Flexibility Act or the 
size standards established by the NRC (10 CFR 2.810).

XI. Backfit Analysis

    The provisions in this final rule allow applicants and licensees to 
voluntarily use NRC-approved ASME Code Cases, sometimes with 
conditions. Thus, the NRC finds that this final rule does not involve 
any provisions that constitute backfitting as defined in 10 CFR 
50.109(a)(1), or otherwise violate the issue finality provisions in 10 
CFR Part 52. Accordingly, a backfit analysis has not been prepared for 
this rule.

List of Subjects in 10 CFR Part 50

    Antitrust, Classified information, Criminal penalties, Fire 
protection, Incorporation by reference, Intergovernmental relations, 
Nuclear power plants and reactors, Radiation protection, Reactor siting 
criteria, Reporting and recordkeeping requirements.

0
For the reasons set forth 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 is revised to read as follows:

    Authority: Secs. 102, 103, 104, 105, 161, 182, 183, 186, 189, 68 
Stat. 936, 937, 938, 948, 953, 954, 955, 956, as amended, sec. 234, 
83 Stat. 444, as amended (42 U.S.C. 2132, 2133, 2134, 2135, 2201, 
2232, 2233, 2236, 2239, 2282); secs. 201, as amended, 202, 206, 88 
Stat. 1242, as amended, 1244, 1246 (42 U.S.C. 5841, 5842, 5846); 
sec. 1704, 112 Stat. 2750 (44 U.S.C. 3504 note); Energy Policy Act 
of 2005, Pub. L. 109-58, 119 Stat. 194 (2005). Section 50.7 also 
issued under Pub. L. 95-601, sec. 10, 92 Stat. 2951 as amended by 
Pub. L. 102-486, sec. 2902, 106 Stat. 3123 (42 U.S. C. 5841), 
Section 50.10 also issued under secs. 101, 185, 68 Stat. 955, as 
amended (42 U.S.C. 2131, 2235); sec. 102, Pub. L. 91-190, 83 Stat. 
853 (42 U.S.C. 4332). Sections 50.13, 50.54(d), and 50.103 also 
issued under sec. 108, 68 Stat. 939, as amended (42 U.S.C. 2138).
    Sections 50.23, 50.35, 50.55, and 50.56 also issued under sec. 
185, 68 Stat. 955 (42 U.S.C. 2235). Sections 50.33a, 50.55a and 
Appendix Q also issued under sec. 102, Pub. L. 91-190, 83 Stat. 853 
(42 U.S.C. 4332). Sections 50.34 and 50.54 also issued under sec. 
204, 88 Stat. 1245 (42 U.S.C. 5844). Sections 50.58, 50.91, and 
50.92 also issued under Pub. L. 97-415, 96 Stat. 2073 (42 U.S.C. 
2239). Section 50.78 also issued under sec. 122, 68 Stat. 939 (42 
U.S.C. 2152). Sections 50.80-50.81 also issued under sec. 184, 68 
Stat. 954, as amended (42 U.S.C. 2234). Appendix F also issued under 
sec. 187, 68 Stat. 955 (42 U.S.C. 2237).


0
2. Section 50.55a is amended by revising paragraphs (b) introductory 
text, (b)(4) introductory text, (b)(5) introductory text, (f)(2), 
(f)(3)(iii)(A), (f)(3)(iv)(A), (f)(4)(ii), (g)(2), (g)(3)(i), 
(g)(3)(ii), (g)(4)(i), and (g)(4)(ii) to read as follows:


Sec.  50.55a  Codes and standards.

* * * * *
    (b) Section III and XI of the ASME Boiler and Pressure Vessel Code 
and the ASME Code for Operation and

[[Page 61336]]

Maintenance of Nuclear Power Plants, which are referenced in paragraphs 
(b)(1), (b)(2), and (b)(3) of this section, were approved for 
incorporation by reference by the Director of the Office of the Federal 
Register pursuant to 5 U.S.C. 552(a) and 1 CFR part 51. NRC Regulatory 
Guide 1.84, Revision 35, ``Design, Fabrication, and Materials Code Case 
Acceptability, ASME Section III'' (July 2010); NRC RG 1.147, Revision 
16, ``Inservice Inspection Code Case Acceptability, ASME Section XI, 
Division 1'' (July 2010); and RG 1.192, ``Operation and Maintenance 
Code Case Acceptability, ASME OM Code'' (June 2003), have been approved 
for incorporation by reference by the Director of the Office of the 
Federal Register pursuant to 5 U.S.C. 552(a) and 1 CFR part 51. These 
RGs list ASME Code cases that the NRC has approved in accordance with 
the requirements in paragraphs (b)(4), (b)(5), and (b)(6) of this 
section. Copies of the ASME Boiler and Pressure Vessel Code and the 
ASME Code for Operation and Maintenance of Nuclear Power Plants may be 
purchased from the American Society of Mechanical Engineers, Three Park 
Avenue, New York, NY 10016. Single copies of NRC RG 1.84, Revision 35; 
1.147, Revision 16; and 1.192 may be obtained free of charge by writing 
the Mail and Messenger Services, U.S. Nuclear Regulatory Commission, 
Washington, DC 20555-0001; or by fax to 301-415-2289; or by e-mail to 
[email protected]. Copies of the ASME Codes and NRC RGs 
incorporated by reference in this section may be inspected at the NRC 
Technical Library, Two White Flint North, 11545 Rockville Pike, 
Rockville, MD 20852-2738, or at the National Archives and Records 
Administration (NARA). For information on the availability of this 
material at NARA, call 202-741-6030, or go to: http://www.archives.gov/federal-register/cfr/ibr-locations.html.
* * * * *
    (4) Design, Fabrication, and Materials Code cases. Applicants and 
licensees may apply the ASME Boiler and Pressure Vessel Code cases 
listed in NRC RG 1.84, Revision 35 without prior NRC approval subject 
to the following:
* * * * *
    (5) In-service Inspection Code cases. Licensees may apply the ASME 
Boiler and Pressure Vessel Code cases listed in RG 1.147, Revision 16, 
without prior NRC approval subject to the following:
* * * * *
    (f) * * *
    (2) For a boiling or pressurized water-cooled nuclear power 
facility whose construction permit was issued on or after January 1, 
1971, but before July 1, 1974, pumps and valves which are classified as 
ASME Code Class 1 and Class 2 must be designed and be provided with 
access to enable the performance of inservice tests for operational 
readiness set forth in editions and addenda of Section XI of the ASME 
Boiler and Pressure Vessel Code incorporated by reference in paragraph 
(b) of this section (or the optional ASME Code cases listed in NRC RG 
1.147, Revision 16 or RG 1.192 that are incorporated by reference in 
paragraph (b) of this section) in effect 6 months before the date of 
issuance of the construction permit. The pumps and valves may meet the 
inservice test requirements set forth in subsequent editions of this 
Code and addenda which are incorporated by reference in paragraph (b) 
of this section (or the optional ASME Code cases listed in NRC RG 
1.147, Revision 16 or RG 1.192 that are incorporated by reference in 
paragraph (b) of this section), subject to the applicable limitations 
and modifications listed therein.
    (3) * * *
    (iii) (A) Pumps and valves, in facilities whose construction permit 
was issued before November 22, 1999, which are classified as ASME Code 
Class 1 must be designed and be provided with access to enable the 
performance of inservice testing of the pumps and valves for assessing 
operational readiness set forth in the editions and addenda of Section 
XI of the ASME Boiler and Pressure Vessel Code incorporated by 
reference in paragraph (b) of this section (or the optional ASME Code 
cases listed in NRC RG 1.147, Revision 16 or RG 1.192 that are 
incorporated by reference in paragraph (b) of this section) applied to 
the construction of the particular pump or valve or the Summer 1973 
Addenda, whichever is later.
* * * * *
    (iv)(A) Pumps and valves, in facilities whose construction permit 
was issued before November 22, 1999, which are classified as ASME Code 
Class 2 and Class 3 must be designed and be provided with access to 
enable the performance of inservice testing of the pumps and valves for 
assessing operational readiness set forth in the editions and addenda 
of Section XI of the ASME Boiler and Pressure Vessel Code incorporated 
by reference in paragraph (b) of this section (or the optional ASME 
Code cases listed in NRC RG 1.147, Revision 16, that are incorporated 
by reference in paragraph (b) of this section) applied to the 
construction of the particular pump or valve or the Summer 1973 
Addenda, whichever is later.
* * * * *
    (4) * * *
    (ii) Inservice tests to verify operational readiness of pumps and 
valves, whose function is required for safety, conducted during 
successive 120-month intervals must comply with the requirements of the 
latest edition and addenda of the Code incorporated by reference in 
paragraph (b) of this section 12 months before the start of the 120-
month interval (or the optional ASME Code cases listed in NRC RG 1.147, 
Revision 16 or RG 1.192 that are incorporated by reference in paragraph 
(b) of this section), subject to the conditions listed in paragraph (b) 
of this section.
* * * * *
    (g) * *
    (2) For a boiling or pressurized water-cooled nuclear power 
facility whose construction permit was issued on or after January 1, 
1971, but before July 1, 1974, components (including supports) which 
are classified as ASME Code Class 1 and Class 2 must be designed and be 
provided with access to enable the performance of inservice examination 
of such components (including supports) and must meet the preservice 
examination requirements set forth in editions and addenda of Section 
XI of the ASME Boiler and Pressure Vessel Code incorporated by 
reference in paragraph (b) of this section (or the optional ASME Code 
cases listed in NRC RG 1.147, Revision 16, that are incorporated by 
reference in paragraph (b) of this section) in effect 6 months before 
the date of issuance of the construction permit. The components 
(including supports) may meet the requirements set forth in subsequent 
editions and addenda of this Code which are incorporated by reference 
in paragraph (b) of this section (or the optional ASME Code cases 
listed in NRC RG 1.147, Revision 16, that are incorporated by reference 
in paragraph (b) of this section), subject to the applicable 
limitations and modifications.
    (3) * * *
    (i) Components (including supports) which are classified as ASME 
Code Class 1 must be designed and be provided with access to enable the 
performance of inservice examination of these components and must meet 
the preservice examination requirements set forth in the editions and 
addenda of Section XI of the ASME Boiler and Pressure Vessel Code 
incorporated by reference in paragraph (b) of this section (or the 
optional ASME Code cases listed

[[Page 61337]]

in NRC RG 1.147, Revision 16, that are incorporated by reference in 
paragraph (b) of this section) applied to the construction of the 
particular component.
    (ii) Components which are classified as ASME Code Class 2 and Class 
3 and supports for components which are classified as ASME Code Class 
1, Class 2, and Class 3 must be designed and be provided with access to 
enable the performance of inservice examination of these components and 
must meet the preservice examination requirements set forth in the 
editions and addenda of Section XI of the ASME Boiler and Pressure 
Vessel Code incorporated by reference in paragraph (b) of this section) 
applied to the construction of the particular component.
* * * * *
    (4) * * *
    (i) Inservice examination of components and system pressure tests 
conducted during the initial 120-month inspection interval must comply 
with the requirements in the latest edition and addenda of the Code 
incorporated by reference in paragraph (b) of this section on the date 
12 months before the date of issuance of the operating license (or the 
optional ASME Code cases listed in NRC RG 1.147, Revision 16, that are 
incorporated by reference in paragraph (b) of this section), subject to 
the conditions listed in paragraph (b) of this section.
    (ii) Inservice examination of components and system pressure tests 
conducted during successive 120-month inspection intervals must comply 
with the requirements of the latest edition and addenda of the Code 
incorporated by reference in paragraph (b) of this section 12 months 
before the start of the 120-month inspection interval (or the optional 
ASME Code cases listed in NRC RG 1.147, Revision 16, that are 
incorporated by reference in paragraph (b) of this section), subject to 
the conditions listed in paragraph (b) of this section.
* * * * *

    Dated at Rockville, Maryland, this 14th day of September 2010.

    For the Nuclear Regulatory Commission.
Cynthia D. Pederson,
 Acting Director, Office of Nuclear Reactor Regulation.
[FR Doc. 2010-24814 Filed 10-4-10; 8:45 am]
BILLING CODE 7590-01-P