[Federal Register Volume 75, Number 85 (Tuesday, May 4, 2010)]
[Proposed Rules]
[Pages 24324-24361]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2010-9700]
[[Page 24323]]
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Part III
Nuclear Regulatory Commission
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10 CFR Part 50
American Society of Mechanical Engineers (ASME) Codes and New and
Revised ASME Code Cases; Proposed Rule
Federal Register / Vol. 75 , No. 85 / Tuesday, May 4, 2010 / Proposed
Rules
[[Page 24324]]
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NUCLEAR REGULATORY COMMISSION
10 CFR Part 50
RIN 3150-AI35
[NRC 2008-0554]
American Society of Mechanical Engineers (ASME) Codes and New and
Revised ASME Code Cases
AGENCY: Nuclear Regulatory Commission (NRC).
ACTION: Proposed rule.
-----------------------------------------------------------------------
SUMMARY: The NRC proposes to amend its regulations to incorporate by
reference the 2005 Addenda through 2008 Addenda of Section III,
Division 1, and the 2005 Addenda through 2008 Addenda of Section XI,
Division 1, of the ASME Boiler and Pressure Vessel Code (ASME B&PV
Code); and the 2005 Addenda and 2006 Addenda of the ASME Code for
Operation and Maintenance of Nuclear Power Plants (ASME OM Code). The
NRC also proposes to incorporate by reference ASME Code Case N-722-1,
``Additional Examinations for PWR Pressure Retaining Welds in Class 1
Components Fabricated With Alloy 600/82/182 Materials Section XI,
Division 1,'' and Code Case N-770, ``Alternative Examination
Requirements and Acceptance Standards for Class 1 PWR [Pressurized-
Water Reactor] Piping and Vessel Nozzle Butt Welds Fabricated with UNS
N06082 or UNS W86182 Weld Filler Material with or without Application
of Listed Mitigation Activities.''
DATES: Submit comments by July 19, 2010. Comments received after this
date will be considered if it is practical to do so, but the NRC is
able to ensure consideration only of comments received on or before
this date.
ADDRESSES: Please include Docket ID NRC-2008-0554 in the subject line
of your comments For instructions on submitting comments and accessing
documents related to this action, see Section I, ``Submitting Comments
and Accessing Information'' in the SUPPLEMENTARY INFORMATION section of
this document. You may submit comments by any one of the following
methods.
Federal Rulemaking Web Site: Go to http://www.regulations.gov and
search for documents filed under Docket ID NRC-2008-0554. Address
questions about NRC dockets to Carol Gallagher, telephone 301-492-3668,
e-mail [email protected].
Mail comments to: Secretary, U.S. Nuclear Regulatory Commission,
Washington, DC 20555-0001, ATTN: Rulemakings and Adjudications Staff.
E-mail comments to: [email protected]. If you do not
receive a reply e-mail confirming that we have received your comments,
contact us directly at 301-415-1677.
Hand-deliver comments to: 11555 Rockville Pike, Rockville, Maryland
20852, between 7:30 a.m. and 4:15 p.m. Federal workdays. (Telephone
301-415-1677)
Fax comments to: Secretary, U.S. Nuclear Regulatory Commission at
301-415-1101.
You may submit comments on the information collections by the
methods indicated in the Paperwork Reduction Act Statement.
FOR FURTHER INFORMATION CONTACT: L. Mark Padovan, Office of Nuclear
Reactor Regulation, U.S. Nuclear Regulatory Commission, Washington, DC
20555-0001, telephone 301-415-1423, e-mail [email protected].
SUPPLEMENTARY INFORMATION:
I. Submitting Comments and Accessing Information
II. Background
III. Discussion of NRC Approval of New Edition and Addenda to the
Code, ASME Code Cases N-722-1 and N-770, and Other Proposed Changes
to 10 CFR 50.55a
a. Quality Standards, ASME Codes and Institute of Electrical and
Electronics Engineers (IEEE) Standards, and Alternatives
b. Applicant/Licensee-Proposed Alternatives to the Requirements
of 10 CFR 50.55a
c. Standards Approved for Incorporation by Reference
d. ASME B&PV Code, Section III
e. ASME B&PV Code, Section XI
f. ASME OM Code
g. Reactor Coolant Pressure Boundary, Quality Group B
Components, and Quality Group C Components
h. Inservice Testing Requirements
i. Inservice Inspection Requirements
j. Substitution of the Term ``Condition'' in 10 CFR 50.55a
IV. Paragraph-by-Paragraph Discussion
V. Generic Aging Lessons Learned (GALL) Report
VI. Specific Request for Comments
VII. Voluntary Consensus Standards
VIII. Finding of No Significant Environmental Impact: Environmental
Assessment
IX. Paperwork Reduction Act Statement
X. Regulatory and Backfit Analysis
XI. Regulatory Flexibility Certification
I. Submitting Comments and Accessing Information
Comments submitted in writing or in electronic form will be posted
on the NRC Web site and on the Federal rulemaking Web site
Regulations.gov. Because your comments will not be edited to remove any
identifying or contact information, the NRC cautions you against
including any information in your submission that you do not want to be
publicly disclosed. The NRC requests that any party soliciting or
aggregating comments received from other persons for submission to the
NRC inform those persons that the NRC will not edit their comments to
remove any identifying or contact information, and therefore, they
should not include any information in their comments that they do not
want publicly disclosed.
You can access publicly available documents related to this
document, including the following documents, using the following
methods:
NRC's Public Document Room (PDR): The public may examine, and have
copied for a fee, publicly-available documents at the NRC's PDR, Room
O1-F21, One White Flint North, 11555 Rockville Pike, Rockville,
Maryland.
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 proposed rule can be found at http://www.regulations.gov by searching on Docket ID NRC-2008-0554.
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Rulemaking Web
Document PDR site Reading room
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ASME B&PV Code*............................................... X ............... ..............
ASME Code Case N-770*......................................... X ............... ..............
ASME Code Case N-772-1*....................................... X ............... ..............
[[Page 24325]]
ASME OM Code*................................................. X ............... ..............
EPRI Report NP-5151**, ``Evaluation of Reactor Vessel Beltline ............... ............... ..............
Integrity Following Unanticipated Operating Events,'' April
1987.........................................................
Final Safety Evaluation by the Office of Nuclear Reactor X ............... ML081140105
Regulation on Topical Report NEI 94-01, Revision 2,
``Industry Guideline for Implementing Performance-Based
Option of 10 CFR Part 50, Appendix J,'' June 25, 2008........
GALL Report, NUREG-1801, Rev.1, September 2005:
Volume 1,................................................. X ............... ML052770419
Volume 2.................................................. X ............... ML052780376
NQA-1*, ``Quality Assurance Requirements for Nuclear ............... ............... ..............
Facilities,'' 1994 Edition...................................
NUREG-1800, Rev. 1, ``Standard Review Plan for Review of X ............... ML052770566
License Renewal Applications for Nuclear Power Plants,
September 2005...............................................
Regulatory and Backfit Analysis for proposed rule............. X X ML092510270
Regulatory Guide 1.178, ``An Approach for Plant-Specific Risk- X ............... ..............
Informed Decisionmaking for Inservice Inspection of Piping''.
Regulatory Guide 1.193, Revision 2, ``ASME Code Cases not X ............... ML072470294
Approved for Use.''..........................................
Regulatory Guide 1.200, ``An Approach for Determining the X ............... ..............
Technical Adequacy of Probabilistic Risk Assessment Results
for Risk-Informed Activities''...............................
Standard Review Plan 3.9.8, ``Risk-Informed Inservice X ............... ..............
Inspection of Piping''.......................................
----------------------------------------------------------------------------------------------------------------
* Available on the ASME Web site.
** Available on the EPRI Web site.
II. Background
The ASME develops and publishes the ASME B&PV Code, which contains
requirements for the design, construction, and inservice inspection
(ISI) of nuclear power plant components; and the ASME OM Code, which
contains requirements for inservice testing (IST) of nuclear power
plant components. The ASME issues new editions of the ASME B&PV Code
every 3 years and issues addenda to the editions yearly except in years
when a new edition is issued. Periodically, the ASME publishes new
editions and addenda of the ASME OM Code. The new editions and addenda
typically revise provisions of the Codes to broaden their
applicability, add specific elements to current provisions, delete
specific provisions, and/or clarify them to narrow the applicability of
the provision. The revisions to the editions and addenda of the Codes
do not significantly change Code philosophy or approach.
The ASME B&PV and OM Codes are national voluntary consensus
standards, and are required by the National Technology Transfer and
Advancement Act of 1995, Public Law 104-113, to be used by government
agencies instead of government-unique standards, unless the use of such
a standard is inconsistent with applicable law or is otherwise
impractical. It has been the NRC's practice to review new editions and
addenda of the ASME B&PV and OM Codes and periodically update 10 CFR
50.55a to incorporate newer editions and addenda by reference. The NRC
approves and/or mandates the use of editions and addenda of the Codes
in 10 CFR 50.55a through the rulemaking process of ``incorporation by
reference.'' As such, each provision of the Codes incorporated by
reference into, and mandated by, 10 CFR 50.55a constitutes a legally-
binding NRC requirement imposed by rule. As the Codes are consensus
documents, there may be disagreement among the technical experts
regarding what constitutes an acceptable level of safety. The NRC
proposed conditions enhance the provisions in the Code in instances
where the NRC has determined that the provisions do not provide an
acceptable level of safety. In other instances, research data or
experience has shown that certain Code provisions are unnecessarily
conservative, and the NRC has determined that the Code revisions are
acceptable. This rulemaking is the latest in a series of rulemakings
which incorporate by reference new editions and/or addenda of the Codes
which are approved for use, either unconditionally or with conditions.
The editions and addenda of the ASME B&PV and OM Codes were last
incorporated by reference into the regulations in a final rule dated
September 10, 2008 (73 FR 52730), as corrected on October 2, 2008 (73
FR 57235), incorporating Section III of the 2004 Edition of the ASME
B&PV Code, Section XI of the 2004 Edition of the ASME B&PV Code, and
the 2004 Edition of the ASME OM Code, subject to NRC conditions.
III. Discussion of NRC Approval of New Edition and Addenda to the
Codes, ASME Code Cases N-722-1 and N-770, and Other Proposed Changes to
10 CFR 50.55a
The NRC proposes to amend its regulations to incorporate by
reference the 2005 Addenda through 2008 Addenda of Section III,
Division 1, and Section XI, Division 1 of the ASME B&PV Code; and the
2005 Addenda and 2006 Addenda of the ASME OM Code into 10 CFR 50.55a.
The NRC also proposes to incorporate by reference Code Case N-770, and
revision 1 to Code Case N-722, which was incorporated by reference into
the NRC's regulations on September 10, 2008 (73 FR 52729).
The NRC follows a three-step process to determine acceptability of
new provisions in new editions and addenda to the Codes, and the need
for conditions on the uses of these Codes. This process was employed in
the review of the Codes that are the subjects of this proposed rule.
First, NRC staff actively participates with other ASME committee
members with full involvement in discussions and technical debates in
the development of new and revised Codes. This includes a technical
justification in support of each new or revised Code. Second, the NRC
committee representatives discuss the Codes and technical
justifications with other cognizant NRC staff to ensure an adequate
technical review. Finally, the proposed NRC position on each Code is
reviewed and approved by NRC management as part of the rulemaking
amending 10 CFR 50.55a to incorporate by reference new editions and
addenda of the ASME Codes, and conditions on
[[Page 24326]]
their use. This regulatory process, when considered together with the
ASME's own process for developing and approving ASME Codes provides
reasonable assurances that the NRC approves for use only those new and
revised Code edition and addenda (with conditions as necessary) that
provide reasonable assurance of adequate protection to public health
and safety and that do not have significant adverse impacts on the
environment.
The NRC reviewed changes to the Codes in the editions and addenda
of the Codes identified in this rulemaking. The NRC concluded, in
accordance with the process for review of changes to the Codes, that
each of the editions and addenda of the Codes, and the 1994 Edition of
NQA-1, are technically adequate, consistent with current NRC
regulations, and approved for use with the specified conditions. Table
1 identifies where the NRC proposes to change (clarify the regulation;
or impose new, revise existing, or remove conditions in) 10 CFR 50.55a.
Due to the extent of the proposed revisions to 10 CFR 50.55a(b)(2), the
NRC is proposing to revise this portion of the regulations in its
entirety, including the redesignation of paragraphs within the section.
These proposed redesignations are also outlined in Table 1 of this
document.
Table 1--Redesignation of Paragraphs and Description of Proposed Changes
to 10 CFR 50.55a
------------------------------------------------------------------------
Current Description of
Proposed regulation regulation proposed changes
------------------------------------------------------------------------
Applicant/Licensee-Proposed Alternatives to the Requirements of 10 CFR
50.55a
------------------------------------------------------------------------
Paragraph (a)................. Paragraph (a).... Revise to title the
paragraph Quality
standards, ASME
Codes and IEEE
standards, and
alternatives.
Paragraph (a)(3).............. Paragraph (a)(3). Revise to clarify
that an alternative
is to be submitted
to, and approved by,
the NRC prior to
implementing the
alternative.
------------------------------------------------------------------------
Standards Approved for Incorporation by Reference
------------------------------------------------------------------------
Introductory text to paragraph Introductory text Revise to title the
(b). to paragraph (b). paragraph Standards
approved for
incorporation by
reference. Revise to
incorporate by
reference the ASME
B&PV Code, Section
III, Division 1
(excluding Non-
mandatory
Appendices), and
Section XI, Division
1, and ASME OM Code,
which are referenced
in paragraphs
(b)(1), (b)(2), and
(b)(3) of this
section. In
addition, ASME Code
Cases N-722-1 and
N[dash]770 would be
incorporated by
reference.
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ASME B&PV Code, Section III
------------------------------------------------------------------------
Introductory text to paragraph Introductory text Revise to clarify the
(b)(1). to paragraph wording and include
(b)(1). the 1974 Edition
(Division 1) through
the 2008 Addenda
(Division 1),
subject to
conditions. Change
``limitations and
modifications'' to
``conditions.''
Paragraph (b)(1)(ii).......... Paragraph Revise the current
(b)(1)(ii), conditions on the
``Weld leg use of stress
dimensions''. indices used for
welds in piping
design under
Subarticles NB-3600,
NC-3600, and ND-
3600. Make editorial
corrections and
additions.
Introductory text to paragraph Introductory text Revise to include the
(b)(1)(iii). to paragraph latest addenda to
(b)(1)(iii), Section III of the
``Seismic design ASME B&PV Code (2006
of piping''. Addenda through the
2008 Addenda) and
Subarticle NB-3200
of the 2004 Edition
through the 2008
Addenda of the ASME
B&PV Code subject to
the condition
outlined in
paragraph
(b)(1)(iii)(B).
Change
``limitation'' to
``condition.''
Paragraphs (b)(1)(iii)(A), ................. Add new conditions on
(b)(1)(iii)(B), and the use of
(b)(1)(iii)(C). Subarticles NB-3200,
NB-3600, NC-3600 and
ND-3600 identified
in the introductory
text to paragraph
(b)(1)(iii).
Paragraph (b)(1)(iv).......... Paragraph Revise to incorporate
(b)(1)(iv) by reference the
``Quality 1994 Edition of NQA-
assurance''. 1, ``Quality
Assurance
Requirements for
Nuclear
Facilities.''
Paragraph (b)(1)(vii)......... ................. Add a new condition
to prohibit the use
of paragraph NB-7742
of the 2006 Addenda
up to and including
the 2007 Edition and
2008 Addenda of the
ASME B&PV Code,
Section III.
------------------------------------------------------------------------
ASME B&PV Code, Section XI
------------------------------------------------------------------------
Introductory text to paragraph Introductory text Revise to clarify the
(b)(2). to paragraph wording and
(b)(2). incorporate by
reference the 2005
Addenda through 2008
Addenda of the ASME
B&PV Code into Sec.
50.55a; only
Subsections IWA,
IWB, IWC, IWD, IWE,
IWF, IWL; Mandatory
and Non-Mandatory
Appendices of
Division 1 are
incorporated by
reference into 10
CFR 50.55a, with
conditions. Change
``limitations and
modifications'' to
``conditions.''
NA............................ Paragraph Remove because
(b)(2)(i), licensees are no
``Limitations on longer using the
specific 1974 and 1977
editions and Editions and addenda
addenda''. of the ASME B&PV
Code.
Paragraph (b)(2)(i)........... Paragraph Redesignate paragraph
(b)(2)(ii), (b)(2)(ii) as
``Pressure- paragraph (b)(2)(i).
retaining welds
in ASME Code
Class 1 piping
(applies to
Table IWB-2500
and IWB-2500-1
and Category B-
J''.
NA............................ Paragraph Remove because the
(b)(2)(iii), condition in the
``Steam paragraph is
generator tubing redundant to the
(modifies 1989 Edition through
Article IWB- the 2008 Addenda of
2000)''. Section XI.
[[Page 24327]]
NA............................ Paragraph Remove because
(b)(2)(iv), licensees are no
``Pressure longer using these
retaining welds older editions and
in ASME Code addenda of the code.
Class 2 piping''.
NA............................ Paragraph Remove because
(b)(2)(v), re: licensees are no
Evaluation longer using the
procedures and Winter 1983 Addenda
acceptance and the Winter 1984
criteria for Addenda of Section
austenitic XI.
piping.
Paragraph (b)(2)(ii).......... Paragraph Redesignate paragraph
(b)(2)(vi), (b)(2)(vi) as
``Effective paragraph
edition and (b)(2)(ii). Change
addenda of ``modified and
Subsection IWE supplemented'' to
and Subsection ``conditioned.''
IWL, Section
XI''.
Paragraph (b)(2)(iii)......... Paragraph Redesignate paragraph
(b)(2)(vii), (b)(2)(vii) as
``Section XI paragraph
references to OM (b)(2)(iii).
Part 4, OM Part
6 and OM Part 10
(Table IWA-1600-
1)''.
Paragraph (b)(2)(iv).......... Paragraph Redesignate paragraph
(b)(2)(viii), (b)(2)(viii) as
``Examination of paragraph
concrete (b)(2)(iv), and
containments''. revise the
introductory text to
remove the
conditions in
redesignated
paragraphs
(b)(2)(iv)(F) and
(b)(2)(iv)(G) when
using the 2007
Edition with 2008
Addenda of the ASME
Code, Section XI.
Paragraph (b)(2)(v)........... Paragraph Redesignate paragraph
(b)(2)(ix), (b)(2)(ix) as
``Examination of paragraph (b)(2)(v),
metal and revise the
containments and introductory text to
the liners of remove the
concrete conditions in
containments''. redesignated
paragraphs
(b)(2)(v)(F),
(b)(2)(v)(G),
(b)(2)(v)(H) and
(b)(2)(v)(I) when
applying the 2004
Edition with 2006
Addenda through the
2007 Edition with
2008 Addenda of the
ASME Code, Section
XI and remove the
condition in
redesignated
paragraph
(b)(2)(v)(I) when
applying the 2004
Edition, up to and
including, the 2005
Addenda. Add a new
condition as
paragraph
(b)(2)(v)(J) on the
use of Article IWE-
5000 of Subsection
IWE when applying
the 2007 Edition up
to and including the
2008 Addenda of the
ASME Code, Section
XI.
Paragraph (b)(2)(vi).......... Paragraph Redesignate paragraph
(b)(2)(x), (b)(2)(x) as
``Quality paragraph
assurance''. (b)(2)(vi).
Paragraph (b)(2)(vii)......... Paragraph Redesignate paragraph
(b)(2)(xi) (b)(2)(xi) as
[Reserved]. paragraph
(b)(2)(vii).
Paragraph (b)(2)(viii)........ Paragraph Redesignate paragraph
(b)(2)(xii), (b)(2)(xii) as
``Underwater paragraph
welding''. (b)(2)(viii).
Paragraph (b)(2)(ix).......... Paragraph Redesignate paragraph
(b)(2)(xiii) (b)(2)(xiii) as
[Reserved]. paragraph
(b)(2)(ix).
Paragraph (b)(2)(x)........... Paragraph Redesignate paragraph
(b)(2)(xiv), (b)(2)(xiv) as
``Appendix VIII paragraph (b)(2)(x).
personnel
qualification''.
Paragraph (b)(2)(xi).......... Paragraph Redesignate paragraph
(b)(2)(xv), (b)(2)(xv) as
``Appendix VIII paragraph (b)(2)(xi)
specimen set and and revise it so
qualification that existing
requirements''. conditions would not
apply to the 2007
Edition through the
2008 Addenda of
Section XI. Change
``provisions'' to
``conditions'' in
the introductory
text to redesignated
paragraphs
(b)(2)(xi),
(b)(2)(xi)(B),
(b)(2)(xi)(C),
(b)(2)(xi)(D),
(b)(2)(xi)(E),
(b)(2)(xi)(F),
(b)(2)(xi)(G),
(b)(2)(xi)(K), and
(b)(2)(xi)(K)(1).
Change ``provisions
of'' to ``conditions
in'' in paragraph
(b)(2)(xi)(G)(3).
Change ``modified''
and ``modification''
to ``conditioned''
and ``condition'' in
(b)(2)(xi)(K)(2)(i),
(b)(2)(xi)(K)(2)(iii
),
(b)(2)(xi)(K)(3)(i),
(b)(2)(xi)(K)(3)(ii)
, (b)(2)(xi)(K)(4),
and (b)(2)(xi)(L),
where applicable.
Paragraph (b)(2)(xii)......... Paragraph Redesignate paragraph
(b)(2)(xvi), (b)(2)(xvi) as
``Appendix VIII paragraph
single side (b)(2)(xii). Change
ferritic vessel ``modified'' to
and piping and ``conditioned'' in
stainless steel redesignated
piping paragraphs
examination''. (b)(2)(xii)(A) and
(b)(2)(xii)(B).
Paragraph (b)(2)(xiii)........ Paragraph Redesignate paragraph
(b)(2)(xvii), (b)(2)(xvii) as
``Reconciliation paragraph
of Quality (b)(2)(xiii).
Requirements''.
Paragraph (b)(2)(xiv)(A)...... Paragraph Redesignate paragraph
(b)(2)(xviii)(A) (b)(2)(xviii)(A) as
, paragraph
``Certification (b)(2)(xiv)(A).
of NDE
personnel''.
Paragraph (b)(2)(xiv)(B)...... Paragraph Redesignate paragraph
(b)(2)(xviii)(B) (b)(2)(xviii)(B) as
, paragraph
``Certification (b)(2)(xiv)(B), and
of NDE revise it so that
personnel''. existing condition
would not apply to
the 2007 Edition
through the 2008
Addenda of Section
XI.
Paragraph (b)(2)(xiv)(C)...... Paragraph Redesignate paragraph
(b)(2)(xviii)(C) (b)(2)(xviii)(C) as
, paragraph
``Certification (b)(2)(xiv)(C), and
of NDE revise it such that
personnel''. the existing
conditions on the
qualification of VT-
3 examination
personnel would not
apply to the 2005
Addenda through the
2008 Addenda of
Section XI.
Paragraph (b)(2)(xv).......... Paragraph Redesignate paragraph
(b)(2)(xix), (b)(2)(xix) as
``Substitution paragraph
of alternative (b)(2)(xv), and
methods''. revise it so that
existing conditions
for the substitution
of alternative
examination methods
would not apply when
using the 2005
Addenda through the
2008 Addenda.
Paragraph (b)(2)(xvi)......... Paragraph Redesignate paragraph
(b)(2)(xx), (b)(2)(xx) as
``System leakage paragraph
tests''. (b)(2)(xvi).
Paragraph (b)(2)(xvii)........ Paragraph Redesignate paragraph
(b)(2)(xxi), (b)(2)(xxi) as
``Table IWB-2500- paragraph
1 examination (b)(2)(xvii).
requirements''.
[[Page 24328]]
Paragraph (b)(2)(xviii)....... Paragraph Redesignate paragraph
(b)(2)(xxii), (b)(2)(xxii) as
``Surface paragraph
examination''. (b)(2)(xviii).
Paragraph (b)(2)(xix)......... Paragraph Redesignate paragraph
(b)(2)(xxiii), (b)(2)(xxiii) as
``Evaluation of paragraph
thermally cut (b)(2)(xix).
surfaces''.
Paragraph (b)(2)(xx).......... Paragraph Redesignate paragraph
(b)(2)(xxiv), (b)(2)(xxiv) as
``Incorporation paragraph
of the (b)(2)(xx), and
performance revise it so that
demonstration existing condition
initiative and would not apply when
addition of using the 2007
ultrasonic Edition through the
examination 2008 Addenda.
criteria''.
Paragraph (b)(2)(xxi)......... Paragraph Redesignate paragraph
(b)(2)(xxv), (b)(2)(xxv) as
``Mitigation of paragraph
defects by (b)(2)(xxi).
modification''.
Paragraph (b)(2)(xxii)........ Paragraph Redesignate paragraph
(b)(2)(xxvi), (b)(2)(xxvi) as
``Pressure paragraph
testing class 1, (b)(2)(xxii).
2, and 3
mechanical
joints''.
Paragraph (b)(2)(xxiii)....... Paragraph Redesignate paragraph
(b)(2)(xxvii), (b)(2)(xxvii) as
``Removal of paragraph
insulation''. (b)(2)(xxiii), and
revise it to refer
to IWA-5242 of the
2003 Addenda through
the 2006 Addenda or
IWA-5241 of the 2007
Edition through the
2008 Addenda of
Section XI of the
ASME B&PV Code for
performing VT-2
visual examination
of insulated
components in
systems borated for
the purpose of
controlling
reactivity.
New paragraph (b)(2)(xxiv), NA............... Add to place
``Analysis of flaws''. conditions on the
use of Section XI,
Nonmandatory
Appendix A,
``Analysis of
Flaws.''
New paragraph (b)(2)(xxv), NA............... Add to place
``Evaluation of unanticipated condition specifying
operating events''. that Section E-1200
of the ASME B&PV
Code, Section XI,
Nonmandatory
Appendix E,
``Evaluation of
Unanticipated
Operating Events,''
is not acceptable
for use.
New paragraph (b)(2)(xxvi), NA............... Add condition that
``Nonmandatory Appendix R''. would require
licensees to submit
an alternative in
accordance with Sec.
50.55a(a)(3), and
obtain NRC
authorization of the
proposed alternative
prior to
implementing Section
XI,
Non[dash]Mandatory
Appendix R, RI-ISI
programs.
------------------------------------------------------------------------
ASME OM Code
------------------------------------------------------------------------
Introductory text to paragraph Introductory text Revise to incorporate
(b)(3). to paragraph by reference the
(b)(3). 2005 and 2006
Addenda of the ASME
OM Code; Subsections
ISTA, ISTB, ISTC,
ISTD; Mandatory
Appendices I and II;
and Nonmandatory
Appendices A through
H and J of the ASME
OM Code into Sec.
50.55a. Change
``limitations and
modifications'' to
``conditions.''
Paragraph (b)(3)(v)........... Paragraph Revise to recognize
(b)(3)(v), that snubbers are
``Subsection tested in accordance
ISTD''. with Section ISTD of
the ASME OM Code
when using the 2006
Addenda and later
editions and addenda
of Section XI of the
ASME B&PV Code.
Paragraph (b)(3)(vi).......... Paragraph Revise to state that
(b)(3)(vi), this paragraph
``Exercise applies only when
interval for using the 1999
manual valves''. through 2005 Addenda
of the ASME OM Code,
as the 2006 Addenda
of the ASME OM Code
was revised to be
consistent with the
conditions in
paragraph
(b)(3)(vi).
------------------------------------------------------------------------
Reactor Coolant Pressure Boundary, Quality Group B Components, and
Quality Group C Components
------------------------------------------------------------------------
Paragraphs (c)(3), (d)(2) and Paragraphs Revise to replace
(e)(2). (c)(3), (d)(2) ``but--'' with
and (e)(2). ``subject to the
following
conditions'' at the
end of the
introductory text to
the paragraphs for
clarity.
------------------------------------------------------------------------
Inservice Testing
------------------------------------------------------------------------
Paragraphs (f)(2), (f)(3)(v), Paragraphs Change ``limitations
and (f)(4). (f)(2), and modifications''
(f)(3)(v), and to ``conditions.''
(f)(4).
Paragraph (f)(5)(iv).......... Paragraph Revise to clarify
(f)(5)(iv). that licensees are
required to submit
requests for relief
based on
impracticality
within 12 months
after the expiration
of the IST interval
for which relief is
being sought.
------------------------------------------------------------------------
Inservice Inspection
------------------------------------------------------------------------
Paragraph (g)(2).............. Paragraph (g)(2). Revise to include
provisions for
examination and
testing snubbers in
Subsection ISTD of
the ASME OM Code,
and the optional
ASME code cases
listed in Regulatory
Guide 1.192. Change
``limitations and
modifications'' to
``conditions.''
Paragraph (g)(3)(i)........... Paragraph Revise to include
(g)(3)(i). provisions for
examination and
testing snubbers in
Subsection ISTD of
the ASME OM Code,
and the optional
ASME code cases
listed in Regulatory
Guide 1.192.
Paragraph (g)(3)(ii).......... Paragraph Revise to include the
(g)(3)(ii). provisions for
examination and
testing snubbers in
Subsection ISTD of
the ASME OM Code,
and the optional
ASME code cases
listed in Regulatory
Guide 1.192.
Paragraph (g)(3)(v)........... Paragraph Change ``limitations
(g)(3)(v). and modifications''
to ``conditions.''
[[Page 24329]]
Introductory text to paragraph Introductory text Revise to include the
(g)(4). to paragraph provisions for
(g)(4). examination and
testing snubbers in
Subsection ISTD of
the ASME OM Code.
Change
``limitation'' to
``condition'' and
``modifications'' to
``conditions.''
Paragraph (g)(4)(i)........... Paragraph Revise to include the
(g)(4)(i). provisions for
examination and
testing snubbers in
Subsection ISTD of
the ASME OM Code,
and the optional
ASME code cases
listed in Regulatory
Guide 1.192. Change
``limitations and
modifications'' to
``conditions.''
Paragraph (g)(4)(ii).......... Paragraph Revise to include the
(g)(4)(ii). provisions for
examination and
testing snubbers in
Subsection ISTD of
the ASME OM Code,
and the optional
ASME code cases
listed in Regulatory
Guide 1.192. Change
``limitations and
modifications'' to
``conditions.''
Paragraph (g)(4)(iii)......... Paragraph Revise to provide the
(g)(4)(iii). proper references to
Section XI, Table
IWB-2500-1,
``Examination
Category B-J,'' Item
Numbers B9.20, B9.21
and B9.22.
Paragraph (g)(4)(iv).......... Paragraph Change ``limitations
(g)(4)(iv). and modifications''
to ``conditions.''
Paragraph (g)(5)(iii)......... Paragraph Revise to clarify
(g)(5)(iii). that a request for
relief must be
submitted to the NRC
no later than 12
months after the
examination has been
attempted during a
given ISI interval
and the ASME B&PV
Code requirement
determined to be
impractical.
Paragraph (g)(5)(iv).......... Paragraph Revise to clarify
(g)(5)(iv). that licensees are
required to submit
requests for relief
based on
impracticality
within 12 months
after the expiration
of the ISI interval
for which relief is
being sought.
Paragraph (g)(6)(ii)(B)....... Paragraph Change
(g)(6)(ii)(B). ``modifications and
limitations'' to
``conditions.''
Paragraphs (g)(6)(ii)(E)(1), Paragraphs Revise to update the
(g)(6)(ii)(E)(2), and (g)(6)(ii)(E)(1) requirements to Code
(g)(6)(ii)(E)(3). , Case N-722-1.
(g)(6)(ii)(E)(2)
, and
(g)(6)(ii)(E)(3)
, ``Reactor
coolant pressure
boundary visual
inspections''.
New paragraph (g)(6)(ii)(F), NA............... Add to incorporate
``Inspection requirements for ASME Code Case N-
class 1 pressurized water 770, ``Alternative
reactor piping and vessel Examination
nozzle butt welds''. Requirements and
Acceptance Standards
for Class 1 PWR
Piping and Vessel
Nozzle Butt Welds
Fabricated with UNS
N06082 or UNS W86182
Weld Filler Material
With or Without
Application of
Listed Mitigation
Activities, Section
XI, Division 1,''
with conditions,
into 10 CFR 50.55a.
Footnote 1.................... Footnote 1....... Revise footnote 1 to
clarify what portion
of welds has to be
inspected during the
plant interval that
remains after
January 1, 2009.
------------------------------------------------------------------------
For redesignated paragraphs in 10 CFR 50.55a, Table 2 cross-
references the proposed regulations with the current regulations, and
Table 3 cross-references the current regulations with the proposed
regulations.
Table 2--Cross Reference of Proposed Regulations With Current
Regulations
------------------------------------------------------------------------
Description of
Proposed regulation Current proposed
regulation redesignations
------------------------------------------------------------------------
ASME B&PV Code, Section XI
------------------------------------------------------------------------
Paragraph (b)(2)(i)........... Paragraph Redesignate paragraph
(b)(2)(ii). (b)(2)(ii) as
paragraph (b)(2)(i).
Paragraph (b)(2)(ii).......... Paragraph Redesignate paragraph
(b)(2)(vi). (b)(2)(vi) as
paragraph
(b)(2)(ii).
Paragraph (b)(2)(iii)......... Paragraph Redesignate paragraph
(b)(2)(vii). (b)(2)(vii) as
paragraph
(b)(2)(iii).
Paragraph (b)(2)(iv).......... Paragraph Redesignate paragraph
(b)(2)(viii). (b)(2)(viii) as
paragraph
(b)(2)(iv).
Paragraph (b)(2)(v)........... Paragraph Redesignate paragraph
(b)(2)(ix). (b)(2)(ix) as
paragraph (b)(2)(v).
Paragraph (b)(2)(vi).......... Paragraph Redesignate paragraph
(b)(2)(x). (b)(2)(x) as
paragraph
(b)(2)(vi).
Paragraph (b)(2)(vii)......... Paragraph Redesignate paragraph
(b)(2)(xi). (b)(2)(xi) as
paragraph
(b)(2)(vii).
Paragraph (b)(2)(viii)........ Paragraph Redesignate paragraph
(b)(2)(xii). (b)(2)(xii) as
paragraph
(b)(2)(viii).
Paragraph (b)(2)(ix).......... Paragraph Redesignate paragraph
(b)(2)(xiii). (b)(2)(xiii) as
paragraph
(b)(2)(ix).
Paragraph (b)(2)(x)........... Paragraph Redesignate paragraph
(b)(2)(xiv). (b)(2)(xiv) as
paragraph (b)(2)(x).
Paragraph (b)(2)(xi).......... Paragraph Redesignate paragraph
(b)(2)(xv). (b)(2)(xv) as
paragraph
(b)(2)(xi).
Paragraph (b)(2)(xii)......... Paragraph Redesignate paragraph
(b)(2)(xvi). (b)(2)(xvi) as
paragraph
(b)(2)(xii).
Paragraph (b)(2)(xiii)........ Paragraph Redesignate paragraph
(b)(2)(xvii). (b)(2)(xvii) as
paragraph
(b)(2)(xiii).
Paragraph (b)(2)(xiv)(A)...... Paragraph Redesignate paragraph
(b)(2)(xviii)(A). (b)(2)(xviii)(A) as
paragraph
(b)(2)(xiv)(A).
Paragraph (b)(2)(xiv)(B)...... Paragraph Redesignate paragraph
(b)(2)(xviii)(B). (b)(2)(xviii)(B) as
paragraph
(b)(2)(xiv)(B).
Paragraph (b)(2)(xiv)(C)...... Paragraph Redesignate paragraph
(b)(2)(xviii)(C). (b)(2)(xviii)(C) as
paragraph
(b)(2)(xiv)(C).
Paragraph (b)(2)(xv).......... Paragraph Redesignate paragraph
(b)(2)(xix). (b)(2)(xix) as
paragraph
(b)(2)(xv).
Paragraph (b)(2)(xvi)......... Paragraph Redesignate paragraph
(b)(2)(xx). (b)(2)(xx) as
paragraph
(b)(2)(xvi).
Paragraph (b)(2)(xvii)........ Paragraph Redesignate paragraph
(b)(2)(xxi). (b)(2)(xxi) as
paragraph
(b)(2)(xvii).
Paragraph (b)(2)(xviii)....... Paragraph Redesignate paragraph
(b)(2)(xxii). (b)(2)(xxii) as
paragraph
(b)(2)(xviii).
Paragraph (b)(2)(xix)......... Paragraph Redesignate paragraph
(b)(2)(xxiii). (b)(2)(xxiii) as
paragraph
(b)(2)(xix).
Paragraph (b)(2)(xx).......... Paragraph Redesignate paragraph
(b)(2)(xxiv). (b)(2)(xxiv) as
paragraph
(b)(2)(xx).
Paragraph (b)(2)(xxi)......... Paragraph Redesignate paragraph
(b)(2)(xxv). (b)(2)(xxv) as
paragraph
(b)(2)(xxi).
Paragraph (b)(2)(xxii)........ Paragraph Redesignate paragraph
(b)(2)(xxvi). (b)(2)(xxvi) as
paragraph
(b)(2)(xxii).
[[Page 24330]]
Paragraph (b)(2)(xxiii)....... Paragraph Redesignate paragraph
(b)(2)(xxvii). (b)(2)(xxvii) as
paragraph
(b)(2)(xxiii).
------------------------------------------------------------------------
Table 3--Cross Reference of Current Regulations With Proposed
Regulations
------------------------------------------------------------------------
Description of
Current regulation Proposed proposed
regulation redesignations
------------------------------------------------------------------------
ASME B&PV Code, Section XI
------------------------------------------------------------------------
Paragraph (b)(2)(ii).......... Paragraph Redesignate paragraph
(b)(2)(i). (b)(2)(ii) as
paragraph (b)(2)(i).
Paragraph (b)(2)(vi).......... Paragraph Redesignate paragraph
(b)(2)(ii). (b)(2)(vi) as
paragraph
(b)(2)(ii).
Paragraph (b)(2)(vii)......... Paragraph Redesignate paragraph
(b)(2)(iii). (b)(2)(vii) as
paragraph
(b)(2)(iii).
Paragraph (b)(2)(viii)........ Paragraph Redesignate paragraph
(b)(2)(iv). (b)(2)(viii) as
paragraph
(b)(2)(iv).
Paragraph (b)(2)(ix).......... Paragraph Redesignate paragraph
(b)(2)(v). (b)(2)(ix) as
paragraph (b)(2)(v).
Paragraph (b)(2)(x)........... Paragraph Redesignate paragraph
(b)(2)(vi). (b)(2)(x) as
paragraph
(b)(2)(vi).
Paragraph (b)(2)(xi).......... Paragraph Redesignate paragraph
(b)(2)(vii). (b)(2)(xi) as
paragraph
(b)(2)(vii).
Paragraph (b)(2)(xii)......... Paragraph Redesignate paragraph
(b)(2)(viii). (b)(2)(xii) as
paragraph
(b)(2)(viii).
Paragraph (b)(2)(xiii)........ Paragraph Redesignate paragraph
(b)(2)(ix). (b)(2)(xiii) as
paragraph
(b)(2)(ix).
Paragraph (b)(2)(xiv)......... Paragraph Redesignate paragraph
(b)(2)(x). (b)(2)(xiv) as
paragraph (b)(2)(x).
Paragraph (b)(2)(xv).......... Paragraph Redesignate paragraph
(b)(2)(xi). (b)(2)(xv) as
paragraph
(b)(2)(xi).
Paragraph (b)(2)(xvi)......... Paragraph Redesignate paragraph
(b)(2)(xii). (b)(2)(xvi) as
paragraph
(b)(2)(xii).
Paragraph (b)(2)(xvii)........ Paragraph Redesignate paragraph
(b)(2)(xiii). (b)(2)(xvii) as
paragraph
(b)(2)(xiii).
Paragraph (b)(2)(xviii)(A).... Paragraph Redesignate paragraph
(b)(2)(xiv)(A). (b)(2)(xviii)(A) as
paragraph
(b)(2)(xiv)(A).
Paragraph (b)(2)(xviii)(B).... Paragraph Redesignate paragraph
(b)(2)(xiv)(B). (b)(2)(xviii)(B) as
paragraph
(b)(2)(xiv)(B).
Paragraph (b)(2)(xviii)(C).... Paragraph Redesignate paragraph
(b)(2)(xiv)(C). (b)(2)(xviii)(C) as
paragraph
(b)(2)(xiv)(C).
Paragraph (b)(2)(xix)......... Paragraph Redesignate paragraph
(b)(2)(xv). (b)(2)(xix) as
paragraph
(b)(2)(xv).
Paragraph (b)(2)(xx).......... Paragraph Redesignate paragraph
(b)(2)(xvi). (b)(2)(xx) as
paragraph
(b)(2)(xvi).
Paragraph (b)(2)(xxi)......... Paragraph Redesignate paragraph
(b)(2)(xvii). (b)(2)(xxi) as
paragraph
(b)(2)(xvii).
Paragraph (b)(2)(xxii)........ Paragraph Redesignate paragraph
(b)(2)(xviii). (b)(2)(xxii) as
paragraph
(b)(2)(xviii).
Paragraph (b)(2)(xxiii)....... Paragraph Redesignate paragraph
(b)(2)(xix). (b)(2)(xxiii) as
paragraph
(b)(2)(xix).
Paragraph (b)(2)(xxiv)........ Paragraph Redesignate paragraph
(b)(2)(xx). (b)(2)(xxiv) as
paragraph
(b)(2)(xx).
Paragraph (b)(2)(xxv)......... Paragraph Redesignate paragraph
(b)(2)(xxi). (b)(2)(xxv) as
paragraph
(b)(2)(xxi).
Paragraph (b)(2)(xxvi)........ Paragraph Redesignate paragraph
(b)(2)(xxii). (b)(2)(xxvi) as
paragraph
(b)(2)(xxii).
Paragraph (b)(2)(xxvii)....... Paragraph Redesignate paragraph
(b)(2)(xxiii). (b)(2)(xxvii) as
paragraph
(b)(2)(xxiii).
------------------------------------------------------------------------
The following paragraphs contain the NRC's evaluation of the
changes to the Code editions and addenda (including new Code
provisions) and Code Cases N-722-1 and N-770, where the NRC proposes to
add new, revise existing, or remove conditions in 10 CFR 50.55a.
Quality Standards, ASME Codes and Institute of Electrical and
Electronics Engineers (IEEE) Standards, and Alternatives
10 CFR 50.55a(a)
The NRC proposes to add the paragraph heading ``Quality standards,
ASME Codes and IEEE standards, and alternatives'' to Sec. 50.55a(a).
This will be consistent with paragraph headings throughout 10 CFR
50.55a.
Applicant/Licensee-Proposed Alternatives to the Requirements of 10 CFR
50.55a
10 CFR 50.55a(a)(3)
The current regulations at Sec. 50.55a(a)(3) do not clearly convey
that alternatives to the requirements of Sec. Sec. 50.55a(c), (d),
(e), (f), (g), and (h) must be submitted to, and authorized by, the NRC
prior to implementing the alternatives. Licensees have misinterpreted
Sec. 50.55a(a)(3) and erroneously concluded that it is permissible to
obtain NRC authorization of an alternative after its implementation.
The NRC proposes to add a sentence to Sec. 50.55a(a)(3) to clarify
that an alternative must be submitted to, and authorized by, the NRC
prior to implementing the alternative.
Standards Approved for Incorporation by Reference
10 CFR 50.55a(b)
The NRC proposes to add the paragraph heading ``Standards approved
for incorporation by reference'' to Sec. 50.55a(b). This will be
consistent with paragraph headings throughout 10 CFR 50.55a.
The question has arisen many times in the past of whether
Subsection NE, ``Class MC Components;'' Subsection NF, ``Supports;''
Subsection NG, ``Core Support Structures;'' and Appendices of the ASME
B&PV Code, Section III, are NRC requirements. The NRC is clarifying in
this section how the regulations in 10 CFR 50.55a apply to these
Section III subsections and appendices. This discussion sets forth the
NRC's views regarding the applicable NRC requirements, clarifies which
portions of Section III are approved for use by applicants and
licensees, identifies which portions of Section III are NRC
requirements, and which portions of Section III are not covered by the
regulations in 10 CFR 50.55a. The requirements of Subsection NH,
``Class 1 Components in Elevated Temperature Service,'' of Section III
are already addressed in Sec. 50.55a(b)(1)(vi), and the bases for
these requirements have been discussed in the final rule (69 FR 58804)
issued on October 1, 2004, that amended 10 CFR 50.55a to incorporate by
reference the 2001 Edition up to and including the 2003 Addenda of the
ASME Code, Section III.
First, it should be noted that in 10 CFR 50.55a, the NRC mandates
the use of Section III, Division 1, rules for ASME Code Class 1, 2, and
3 components in 10 CFR 50.55a(c), (d) and (e), respectively.
Specifically, 10 CFR 50.55a(c), (d) and (e) state that for applicants
constructing a nuclear power plant, those components which are part of
the reactor coolant pressure boundary must meet the requirements for
Class 1 components in Section III (e.g.,
[[Page 24331]]
Subsection NB, ``Class 1 Components''); components classified as
Quality Group B must meet the requirements for Class 2 components
(e.g., Subsection NC, ``Class 2 Components''); and components
classified as Quality Group C must meet the requirements for Class 3
components (e.g., Subsection ND, ``Class 3 Components''). The NRC
considers the rules of Subsection NCA and Section III mandatory
appendices to be mandated as well, but only as they apply to Class 1,
2, and 3 components because the language in 10 CFR 50.55a(c), (d) and
(e) also covers general requirements in Subsection NCA and mandatory
appendices in Section III that are applicable to Class 1, 2, and 3
components.
In addition, the introductory text of 10 CFR 50.55a(b) states, in
part, that the ASME Code, Section III, is approved for incorporation by
reference by the Director of the Federal Register pursuant to 5 U.S.C.
552(a) and 1 CFR part 51. However, the regulatory language does not
identify specific subsections in Section III that are incorporated by
reference, and one can only assume that all of Section III (including
all subsections, appendices and Division 2 and 3 rules) are
incorporated by reference. Although it is clear that Subsections NB, NC
and ND are regulatory requirements because they are mandated by 10 CFR
50.55a(c), (d) and (e) as discussed in this document, the lack of
specific rule language in 10 CFR 50.55a mandating the use of
Subsections NE, NF, and NG have created confusion about the regulatory
requirements applicable to Subsections NE, NF, and NG. Subsection NE
provides rules for constructing metal containment components (Class
MC). Subsection NF provides rules for constructing supports for Class
1, 2, 3, and MC components. Subsection NG provides rules for
constructing reactor core support structures. In this sense,
``constructing'' is an all-inclusive term that comprises the design,
fabrication, installation, examination, testing, inspection and
selection of materials for nuclear power plant components.
The NRC is, therefore, clarifying that when Subsections NE, NF and
NG are incorporated by reference, but not mandated, these subsections
are not NRC requirements. Rather, the NRC considers Subsections NE, NF
and NG to be approved by the NRC for use by applicants and licensees of
nuclear power plants by virtue of the NRC's overall approval of Section
III, Division 1 rules without condition. In this manner, approval of
the rules in Subsections NE, NF and NG is similar to regulatory
guidance provided in NRC regulatory guides in that it provides an
acceptable method for meeting NRC requirements and, in this particular
case, in 10 CFR Part 50, Appendix A, General Design Criterion (GDC) 1,
``Quality standards and records.'' Applicants and licensees may propose
means other than those specified by the provisions in Subsections NE,
NF and NG for meeting the applicable regulation. It should be noted
that the NRC reviews an applicant's proposed means of meeting the
requirements of GDC 1 as part of its review of an application for each
manufacturing license, standard design approval, standard design
certification and combined license under 10 CFR part 52 and for each
construction permit and operating license under 10 CFR part 50 using
the guidelines of NRC NUREG-0800, ``Standard Review Plan [SRP] for the
Review of Safety Analysis Reports for Nuclear Power Plants--LWR
Edition.'' During its review of new reactor designs under 10 CFR part
52, the NRC is reviewing the criteria and extent of compliance of
standard plant designs and combined licenses with the rules of the
specific edition and addenda to Subsections NE, NF and NG for
applicability to these new reactor designs. The process being used by
the NRC in the review of Subsections NE, NF, and NG for new reactors as
described in this document is essentially the same process used by the
NRC for the licensing of all nuclear power plants since the SRP was
first issued in 1975. Therefore, this clarification does not establish
new positions or requirements in the regulatory application of
Subsections NE, NF and NG to the construction of nuclear power plants.
Because the NRC staff participates on the ASME Code committees in
the development of and revisions to Subsections NE, NF and NG, the NRC
is cognizant of the acceptability of the Code rules applicable to
Subsections NE, NF and NG. NRC use of consensus technical standards
meets the requirements of Public Law 104-113, ``National Technology
Transfer and Advancement Act of 1995,'' which requires Federal agencies
to use technical standards that are developed by voluntary consensus
standards bodies, instead of government-unique standards, as a means to
carry out policy objectives or activities determined by Federal
agencies, unless contrary to law or the use of the standard is
impractical.
Consistent with this discussion, the NRC does not propose to
substantially change the language in the introductory text to 10 CFR
50.55a(b). The NRC proposes to modify the regulatory language in the
introductory text of 10 CFR 50.55a(b) to clarify that non-mandatory
appendices are excluded from Section III rules that are incorporated by
reference because the NRC does not review the acceptability of non-
mandatory Section III appendices. Similarly, the NRC proposes to
clarify in the introductory text of 10 CFR 50.55a(b) that only Division
1 rules of Section III and Section XI are incorporated by reference
(i.e., Divisions 2 and 3 rules are not incorporated by reference and
are not approved by the NRC regulations in 10 CFR 50.55a). The NRC is
also proposing to incorporate by reference ASME Code Case N-722-1,
``Additional Examinations for PWR Pressure Retaining Welds in Class 1
Components Fabricated With Alloy 600/82/182 Materials Section XI,
Division 1,'' and Code Case N-770, ``Alternative Examination
Requirements and Acceptance Standards for Class 1 PWR [Pressurized-
Water Reactor] Piping and Vessel Nozzle Butt Welds Fabricated with UNS
N06082 or UNS W86182 Weld Filler Material with or without Application
of Listed Mitigation Activities.''
ASME B&PV Code, Section III
The NRC proposes to:
Revise the current regulations in Sec. 50.55a(b)(1),
(b)(1)(ii), and (b)(1)(iii) to detail the specific ASME B&PV Code,
Section III Subsections which are referenced in the ensuing paragraphs.
Revise the current requirements in these paragraphs to
include the latest editions and addenda incorporated into Section III
of the ASME B&PV Code with respect to the regulations regarding seismic
design.
Clarify the current wording of the introductory text of
Sec. 50.55a(b)(1).
Modify the current conditions in Sec. 50.55a(b)(1)(ii) on
the use of stress indices used for welds in piping design under
Subarticles NB-3600, NC-3600, and ND-3600.
Add three new requirements at Sec. 50.55a(b)(1)(iii)(A),
(b)(1)(iii)(B), and (b)(1)(iii)(C) to impose conditions on the use of
Subarticles NB-3200, NB-3600, NC-3600 and ND-3600 identified in Sec.
50.55a(b)(1)(iii).
Introductory Text to 10 CFR 50.55a(b)(1)
The proposed amendment to the introductory text of Sec.
50.55a(b)(1) would revise the language to clarify that references to
Section III refer to Section III of the ASME Boiler and Pressure Vessel
Code.
[[Page 24332]]
10 CFR 50.55a(b)(1)(ii) and (b)(1)(iii) Weld-Leg Dimensions and Seismic
Design of Piping
The current requirements regarding piping seismic rules in Section
III the ASME B&PV Code were first introduced in the 1994 Addenda to the
ASME B&PV Code. These rules were subsequently modified in the 2001
Edition and 2002 Addenda to the ASME B&PV Code. The current regulations
in Sec. 50.55a(b)(1)(ii) outline the conditions on the use of stress
indices used for welds in piping design under Subarticles NB-3600, NC-
3600, and ND-3600. The current regulations in Sec. 50.55a(b)(1)(iii)
only allow the use of ASME B&PV Code, Section III, 1993 Addenda and
earlier editions with respect to Subarticles NB-3200, NB-3600, NC-3600,
and ND-3600.
The current version of the ASME B&PV Code does not adequately
address the seismic design requirements specified in Subparagraphs NB-
3683.2(c), NB-3683.4(c)(1) and (c)(2), and Paragraph NB-3656, Figures
NB-3222-1, NC-3673.2(b)-1, and ND-3673.2(b)-1 and Table 3681(a)-1 of
the ASME B&PV Code. The proposed amendment would modify Sec.
50.55a(b)(1)(ii) to address the NRC's concern about the undersized
weld-leg dimension of less than 1.09t that makes the weld weaker than
the pipe. Additional requirements regarding the stress indices
identified in the proposed addition to the regulations (i.e. Sec.
50.55a(b)(1)(iii)(A)) are warranted based on industry testing which
supports the NRC's position. Additionally, the proposed requirement in
Sec. 50.55a(b)(1)(iii)(B) would resolve an issue identified by the NRC
staff regarding the inclusion of reversing dynamic loads when
calculating the primary bending stresses for Level B service limits.
The proposed condition in Sec. 50.55a(b)(1)(iii)(C) is part of the
ASME B&PV Code requirements for applying the seismic design rules in
Subarticles NB-3600, NC-3600, and ND-3600 in the 2006 Addenda through
the 2008 Addenda.
The current regulations in Sec. 50.55a(b)(1) and (b)(1)(iii)
reference the current seismic design requirements of Section III of the
ASME B&PV Code. The proposed modification would allow the use of the
latest edition and addenda of Section III of the ASME B&PV Code with
the three proposed additional requirements at Sec.
50.55a(b)(1)(iii)(A), (b)(1)(iii)(B), and (b)(1)(iii)(C) which would
provide three conditions on the use of the latest ASME B&PV Code
edition and addenda. The current requirements in Sec. 50.55a(b)(1)(ii)
limit the use of certain stress indices used for welds in the piping
design portions of Section III of the ASME B&PV Code. The proposed
modification would also revise the current conditions on the use of the
stress indices outlined in Sec. 50.55a(b)(1)(ii).
The proposed condition identified in Sec. 50.55a(b)(1)(ii) would
address the NRC concerns with the undersized welds (Cx =
0.75 tn), which are not acceptable because the current ASME
Code design rules would result in a circumferential, fillet-welded or
socket-welded joint where the weld size is smaller than the adjoining
pipe wall thickness. An editorial addition would also be included in
the proposed condition and would reflect the addition of a condition on
the use of paragraph NB-3683.4(c)(2). The use of paragraph NB-
3683.4(c)(1) is currently not allowed and would continue to be
prohibited in the proposed rulemaking. The addition of the condition on
the use of paragraph NB-3683.4(c)(2) is purely editorial in nature
since, by imposing a condition on the use of NB-3683.4(c)(1), the
regulations would inherently impose a condition on the use of NB-
3683.4(c)(2) given their use within Section III of the ASME B&PV Code.
Therefore, this condition would not be new from a technical standpoint.
Also, an editorial correction would be made regarding Footnote 11,
which should be the Footnote 13 for the 2004 Edition through the 2008
Addenda in Figure NC-3673.2(b)-1 and Figure ND-3673.2(b)-1.
The proposed addition identified as Sec. 50.55a(b)(1)(iii)(A)
would address the NRC's position regarding the B2' indices
in paragraph NB-3656 of Section III of the ASME B&PV Code. The NRC
proposes this condition to capture the dynamic strain aging effects
that were reflected in the testing performed by Battelle Columbus
Laboratories which concluded that ferritic steels tend to have lower
margins and a decrease in toughness at higher temperatures due to
dynamic strain aging. (See NUREG/CR-6226, ``Effect of Dynamic Strain
Aging on the Strength and Toughness of Nuclear Ferritic Piping at LWR
Temperatures'' for the Battelle testing results). Therefore, this
additional requirement would provide the means necessary to prevent
significant reductions in the margins of ferritic steel components
(elbows and tees) at high temperatures, thus providing better assurance
of the materials' structural integrity.
The proposed addition identified as Sec. 50.55a(b)(1)(iii)(B)
would address the NRC's position regarding Note (1) of Figure NB-3222-1
of Section III of the ASME B&PV Code. The NRC proposes this condition
based on the premise that while the inclusion of reversing dynamic
loads in the calculation of primary bending stresses for Level B
service limits may not be warranted when the Operating Basis Earthquake
is not included in the design basis for the facility, at other times
these loads must be considered. Such is the case when a licensee's
Operating Basis Earthquake level is more than one-third the value of
the Safe Shutdown Earthquake. However, the current wording of Note (1)
in Figure NB-3222-1 of Section III of the ASME B&PV Code does not
account for this situation. Therefore, the NRC proposes to include this
condition on the use of the latest addenda of Section III of the ASME
B&PV Code.
The proposed addition identified as Sec. 50.55a(b)(1)(iii)(C)
would address the NRC's position regarding the limitation of
Do/t ratio of ASME Class 1, 2 and 3 piping when applying
Subarticles NB-3600, NC-3600 and ND-3600 in the 2006 Addenda through
the 2008 Addenda of Section III of the ASME B&PV Code. In the 1994
Addenda, the Do/t ratio was identified by ASME Code
Committee to be 50 or less for applying the seismic rules in
Subarticles NB-3600, NC-3600 and ND-3600. This upper limit for
Do/t was revised to be 40 in the 2002 Addenda through the
2008 Addenda based on EPRI testing associated with reversing dynamic
seismic loading. However, the 2007 Edition allows Do/t to be
greater than 50 in Note 1 to Table NB 3681(a)-1 and Note 3 to Figures
NC/ND-3673.2(b)-1. NUREG-1367 limits Do/t to no more than 50
for functional capability considerations. To ensure consistency with
ASME B&PV Code requirements found in paragraphs NB-3656, NC-3655, and
ND-3655, Do/t should be limited to no more than 40.
Furthermore, the use of Do/t larger than 40 would be beyond
the piping configuration included in the EPRI testing, and thus is not
justified for design considerations. Therefore, the NRC concludes that
the applicable Do/t for the seismic design of piping as
limited by the ASME B&PV Code in Subarticles NB-3600, NC-3600, and ND-
3600 in the 2006 Addenda through the 2008 Addenda must not be greater
than 40 as addressed in Sec. 50.55a(b)(1)(iii)(C).
10 CFR 50.55a(b)(1)(iv) Quality Assurance
The proposed amendment would revise Sec. 50.55a(b)(1)(iv) to be
consistent with a revised quality assurance provision in the 2006
Addenda of the ASME B&PV Code, Section III,
[[Page 24333]]
Subsection NCA. The proposed amendment would allow the use of 1994
Edition of NQA-1, ``Quality Assurance Requirements for Nuclear Facility
Applications,'' when using the 2006 Addenda of Section III of the ASME
B&PV Code and later editions and addenda. The reference to ASME NQA-1
in Article 4000 of the ASME B&PV Code, Section III was updated to a
later edition of NQA-1 in the 2006 Addenda. NCA-4110(b) was revised to
require that the N-Type Certificate Holders comply with the Basic
Requirements and Supplements of the ASME NQA-1-1994 Edition. Previous
editions/addenda of the ASME B&PV Code, Section III referenced earlier
editions and addenda of ASME NQA-1. There are no significant
differences between of NQA-1-1994 Edition and the editions and addenda
of NQA-1 currently referenced in the regulation. The NRC has reviewed
and found the changes to Subsection NCA that reference the 1994 Edition
of NQA-1 to be acceptable.
10 CFR 50.55a(b)(1)(vii) Capacity Certification and Demonstration of
Function of Incompressible-Fluid Pressure-Relief Valves (New)
The proposed addition identified as Sec. 50.55a(b)(1)(vii) would
modify requirements in Subsection NB of the ASME B&PV Code, Section
III, for certifying the capacity of incompressible-fluid, pressure-
relief valves when the testing facility has less than the full range of
pressure capability necessary for achieving valve set-pressure
conditions during the testing. In the 2006 Addenda, new requirements
were added to the ASME B&PV Code, Section III, that have a parallel
structure in paragraphs NB-7742, NC-7742, and ND-7742 for Class 1, 2,
and 3 incompressible-fluid, pressure-relief valves, respectively. These
new paragraphs address new valve designs having a range of possible
sizes and set-pressure conditions. The method described in these
paragraphs for performing the tests and evaluating data involves
performing tests at less than the highest value of the set-pressure
range, and establishing an incompressible fluid flow coefficient of
discharge that then allows extrapolation of capacities to higher
pressures.
These paragraphs are new, and did not exist in prior editions or
addenda of the ASME B&PV Code, Section III. These new paragraphs
address circumstances in which a certified test facility lacks the
fluid-pressure capability at the necessary flow rate for testing a new,
incompressible-fluid, pressure-relief valve design. The NRC has
identified no issues with performing the tests at less than the highest
value of the set-pressure range for incompressible-fluid, pressure-
relief valves, and finds these new requirements for Class 2 and 3
components acceptable as described in paragraphs NC-7742 and ND-7742.
However, the NRC has identified missing words from paragraph NB-7742
for Class 1 components. The parallel structure of the counterpart
paragraphs (NC-7742 and ND-7742) reveals that the words ``for the
design and the maximum set pressure'' are missing from subparagraph NB-
7742(a)(2). Without these words, the paragraph is confusing, illogical,
and could lead to a non-conservative interpretation of the required
test pressures for new Class 1 incompressible-fluid, pressure-relief
valve designs. Because the new paragraph NB-7742 does not contain the
above-described words, the NRC finds that the paragraph is not
acceptable for use. New Class 1 incompressible-fluid, pressure-relief
valve designs must be tested at the highest values of set-pressure
ranges as required by prior editions and addenda of the ASME B&PV Code,
Section III.
ASME B&PV Code, Section XI
The current regulations in Sec. 50.55a(b)(2) incorporate by
reference ASME B&PV Code, Section XI, 1970 Edition through the 1976
Winter Addenda; and the 1977 Edition (Division 1) through the 2004
Addenda (Division 1), subject to the conditions identified in current
Sec. 50.55a(b)(2)(i) through (b)(2)(xxvii). The proposed amendment
would revise the introductory text to Sec. 50.55a(b)(2) to incorporate
by reference the 2005 Addenda (Division 1) through the 2008 Addenda
(Division 1) of the ASME B&PV Code, Section XI, clarify the wording,
and remove or revise some of the conditions as explained in this
document.
Introductory Text of 10 CFR 50.55a(b)(2)
The proposed amendment to the introductory text of Sec.
50.55a(b)(2) would revise the language to clarify that references to
Section XI refer to Section XI of the ASME Boiler and Pressure Vessel
Code.
10 CFR 50.55a(b)(2)(i) Limitations on Specific Editions and Addenda
(Current)
The NRC proposes to remove Sec. 50.55a(b)(2)(i) from the current
regulations. This paragraph currently specifies which addenda may be
used when applying the 1974 and 1977 Editions of Section XI of the ASME
B&PV Code. Section 50.55a(g)(4)(ii) requires that licensees' successive
120-month inspection intervals comply with the requirements of the
latest edition and addenda of the code incorporated by reference in
Sec. 50.55a(b)(2). Subsequently, licensees are no longer using these
older editions (1974 and 1977 Editions) and addenda of the ASME B&PV
Code, and therefore the NRC proposes to remove this paragraph.
This paragraph will be replaced by the current Sec.
50.55a(b)(2)(ii) which describes a method for determining the extent of
examination of Code Class 1 piping welds for facilities where the
application for a construction permit was docketed prior to July 1,
1978.
10 CFR 50.55a(b)(2)(iii) Steam Generator Tubing (Current)
The NRC proposes to remove Sec. 50.55a(b)(2)(iii) from the current
regulations. The current regulations in Sec. 50.55a(b)(2)(iii) state
that if the technical specifications of a nuclear power plant include
surveillance requirements for steam generators different than those in
Section XI, Article IWB-2000, the ISI program of steam generator tubing
is governed by the requirements in the technical specifications. The
1989 Edition through the 2008 Addenda of Section XI IWB-2413,
``Inspection Program for Steam Generator Tubing,'' state that ``The
examinations shall be governed by the plant Technical Specification.''
Since the condition in Sec. 50.55a(b)(2)(iii) is redundant to the 1989
Edition through the 2008 Addenda of Section XI, the NRC proposes to
remove this condition.
This paragraph will be replaced by the current Sec.
50.55a(b)(2)(vii) which describes Section XI references to OM Part 4,
OM Part 6 and OM Part 10 of the ASME OM Code.
10 CFR 50.55a(b)(2)(iv) Pressure-Retaining Welds in ASME Code Class 2
Piping (Current)
The NRC proposes to remove Sec. 50.55a(b)(2)(iv) from the current
regulations. This paragraph states how to select appropriate Code Class
2 pipe welds in residual heat removal systems, emergency core cooling
systems, and containment heat removal systems when applying editions
and addenda up to the 1983 Edition through the Summer 1983 Addenda of
Section XI of the ASME B&PV Code. Section 50.55a(g)(4)(ii) requires
that licensee's successive 120-month inspection intervals comply with
the requirements of the latest edition and addenda of the code
incorporated by reference in Sec. 50.55a(b)(2). Subsequently,
licensees
[[Page 24334]]
are no longer using these older editions and addenda of the code
(editions and addenda up to the 1983 Edition through the Summer 1983
Addenda of Section XI), and therefore, the NRC proposes to remove the
requirements of current Sec. 50.55a(b)(2)(iv).
This paragraph will be replaced by the current Sec.
50.55a(b)(2)(viii) which describes examinations of concrete
containments.
10 CFR 50.55a(b)(2)(v) Evaluation Procedure and Acceptance Criteria for
Austenitic Piping (Current)
The NRC proposes to remove Sec. 50.55a(b)(2)(v) from the current
regulations. This paragraph deals with evaluation procedures and
acceptance criteria for austenitic piping when applying the Winter 1983
Addenda and the Winter 1984 Addenda of Section XI. Section
50.55a(g)(4)(ii) requires that licensees' successive 120-month
inspection intervals comply with the requirements of the latest edition
and addenda of the code incorporated by reference in Sec.
50.55a(b)(2). Subsequently, licensees are no longer using these older
editions and addenda of the code (editions and addenda up to the 1983
Edition through the Summer 1983 Addenda of Section XI), and therefore,
the NRC proposes to remove the requirements of current Sec.
50.55a(b)(2)(iv). This paragraph will be replaced by the current Sec.
50.55a(b)(2)(ix) which describes examination of metal containments and
the liners of concrete containments.
10 CFR 50.55a(b)(2)(vi) Effective Edition and Addenda of Subsection IWE
and Subsection IWL, Section XI (Current); 10 CFR 50.55a(b)(2)(ii)
(Redesignated)
The NRC proposes to redesignate Sec. 50.55a(b)(2)(vi) in the
current rule to Sec. 50.55a(b)(2)(ii) in the proposed rule. This
paragraph stipulates the editions and addenda of Subsection IWE and
Subsection IWL of Section XI of the ASME B&PV Code which are approved
for use when licensees are implementing the initial 120-month
inspection interval for containment inservice inspection requirements
found in Section XI of the Code. The current paragraph also indicates
that the use of these applicable editions and addenda is subject to the
conditions found in Sec. 50.55a(b)(2)(viii) and (b)(2)(ix) for
Subsection IWL and Subsection IWE, respectively. The proposed rule
would redesignate Sec. 50.55a(b)(2)(viii) and (b)(2)(ix) as Sec.
50.55a(b)(2)(iv) and (b)(2)(v), respectively, and conforming changes
would be made to the references contained in redesignated Sec.
50.55a(b)(2)(ii). Additionally, the proposed rule would change the
words ``modified and supplemented'' to ``conditioned'' for
clarification purposes.
10 CFR 50.55a(b)(2)(viii) Examination of Concrete Containments
(Current); 10 CFR 50.55a(b)(2)(iv) (Redesignated)
The NRC proposes to redesignate Sec. 50.55a(b)(2)(viii) in the
current rule to Sec. 50.55a(b)(2)(iv) in the proposed rule. This
paragraph stipulates the conditions that apply to the inservice
examination of concrete containments using Subsection IWL of various
editions and addenda of the ASME B&PV Code, Section XI, incorporated by
reference in Sec. 50.55a(b)(2). The current regulations, in part,
require that licensees applying Subsection IWL, 2001 Edition through
the 2004 Edition shall apply the conditions in Sec.
50.55a(b)(2)(viii)(E) through (b)(2)(viii)(G). The NRC proposes to
remove the conditions in redesignated Sec. 50.55a(b)(2)(iv)(F) and
(b)(2)(iv)(G) of the proposed rule when applying Subsection IWL of the
2007 Edition with 2008 addenda of the ASME B&PV Code, Section XI
because the intent of these conditions has been incorporated into the
2007 Edition with the 2008 addenda of the ASME B&PV Code, as explained
in this document. Accordingly, the proposed rule would require that
licensees applying Subsection IWL, 2007 Edition with the 2008 Addenda
shall apply only the condition in redesignated Sec.
50.55a(b)(2)(iv)(E). Further, in the proposed rule, the conditions in
redesignated Sec. 50.55a(b)(2)(iv)(E) through (b)(2)(iv)(G) remain
applicable to licensees applying Subsection IWL, 2004 Edition through
the 2006 Addenda.
The condition in the redesignated Sec. 50.55a(b)(2)(iv)(F) relates
to qualification of personnel that examine containment concrete
surfaces and tendon hardware, wires, or strands. This condition in the
current regulations states that personnel that examine containment
concrete surfaces and tendon hardware, wires, or strands must meet the
qualification provisions in IWA-2300, and that the ``owner-defined''
personnel qualification provisions in IWL-2310(d) are not approved for
use. IWA-2300 stipulates qualification provisions for personnel
performing nondestructive examination, including VT-1, VT-2, and VT-3
visual examinations. Paragraph IWA-2312(c) requires training,
qualification, and certification of visual examination personnel to
comply with the requirements of Appendix VI of the Code, which makes
reference to ANSI/ASNT CP-189, and allows for limited certification
(for personnel who are restricted to performing examinations of limited
or specific scope, i.e., limited operations or limited techniques) per
IWA-2350.
In Subsection IWL of the 2007 Edition, the ASME revised paragraph
IWL-2100 to state, in part, that except as noted in IWL-2320, the
requirements of IWA-2300 do not apply. Also, the 2007 Edition deleted
subparagraphs IWL-2310(d) and IWL-2310(e), which allowed certain
requirements (i.e., requirements for personnel qualification and
requirements for visual examination of concrete and tendon anchorage
hardware, wires, or strands) to be owner-defined. Further, the 2007
Edition with 2008 Addenda added a new paragraph IWL-2320 ``Personnel
Qualifications'' and re-designated the former IWL-2320 ``Responsible
Engineer'' as IWL-2330 ``Responsible Engineer.''
The new paragraph IWL-2320 stipulates specific plant experience,
training, written and practical examination and frequency of
administration to demonstrate training proficiency, and vision test
requirements for qualification of personnel approved by the Responsible
Engineer for performing general or detailed visual examinations of
structural concrete, reinforcing steel and post-tensioning system
components (i.e., wires, strands, anchorage hardware, corrosion
protection medium and free water) of Class CC containments. The
provision requires documentation of qualification requirements in the
Employer's written practice. The Responsible Engineer is responsible
for approval, instruction and training of personnel performing general
and detailed visual examinations. The new provision also provided the
requisite detailed requirements for the instruction material to be used
to qualify personnel performing IWL inspections. Specifically, the
addition included requirements for preservice and inservice inspections
for concrete (references American Concrete Institute 201.1R),
reinforcing steel, and post-tensioning items such as wires, strands,
anchorage hardware, corrosion protection medium, and free water. Thus,
the qualification requirements adequately include the areas and extent
of required plant experience, instructional topics for classroom
training in IWL requirements and plant-specific IWL visual examination
procedures, and require the vision test requirements of IWA-2321. The
new paragraph IWL-2320, ``Personnel Qualifications,'' details specific
[[Page 24335]]
guidance for personnel qualification for containment concrete and
reinforcing steel and post-tensioning system visual inspections that
provide an acceptable level of quality and safety similar to the
requirements in IWA-2300 and therefore, addressed the intent of the
conditions in Sec. 50.55a(b)(2)(viii)(F) of the current regulations.
Therefore, the condition in redesignated Sec. 50.55a(b)(2)(iv)(F) is
not required to be applied for licensees using Subsection IWL, 2007
Edition with the 2008 Addenda. It is noted that the NRC's acceptance of
the new code provision IWL-2320, ``Personnel Qualifications,'' is based
on paragraph IWL-2320 of the 2007 Edition as supplemented by the
addition by errata in the 2008 addenda.
The condition in redesignated Sec. 50.55a(b)(2)(iv)(G) of the
proposed rule requires that corrosion protection material be restored
following concrete containment post-tensioning system repair and
replacement activities in accordance with the quality assurance program
requirements specified in IWA-1400.'' In the 2007 Edition of Subsection
IWL, the following revisions were made related to corrosion protection
medium for post-tensioning systems:
1. The revised paragraph IWL 4110 added footnote 1 which states
that the corrosion protection medium is exempt from the requirements of
IWL-4000. However, corrosion protection medium must be restored in
accordance with IWL-2526 following concrete containment post-tensioning
system repair/replacement activities.
2. The revised Line Item L2.40 ``Corrosion Protection Medium'' of
Table IWL-2500-1 added reference to paragraph IWL-2526 in the columns
for Test or Examination Requirement, Test or Examination Method, and
Extent of Examination.
3. In the revised paragraph IWL-2526, subparagraph (b) requires
that following the completion of tests and examinations required by
Examination Category L-B, Items L2.10, L.2.20, and L2.30, the corrosion
protection medium must be replaced to ensure sufficient coverage of
anchorage hardware, wires, and strands. The total amount replaced in
each tendon sheath must be recorded and differences between amount
removed and amount replaced must be documented.
4. In the revised paragraph IWL-2526, subparagraph (d) requires
that the Responsible Engineer specify the method for corrosion
protection medium.
With the understanding that the Responsible Engineer (who per IWL-2320
is a Registered Professional Engineer) will ensure that the corrosion
protection medium is restored in accordance with the applicable Quality
Assurance Program, the revised paragraphs IWL-4110(b)(3) [with footnote
1] and IWL-2526, and revised line item L2.40 in Table IWL-2500-1 of
Subsection IWL, 2007 Edition through the 2008 Addenda adequately
incorporated the intent of the condition in Sec. 50.55a(b)(2)(viii)(G)
of the current regulations and is acceptable to the NRC. Therefore, the
condition in redesignated Sec. 50.55a(b)(2)(iv)(G) is not required to
be applied for licensees using Subsection IWL, 2007 Edition through the
2008 Addenda.
10 CFR 50.55a(b)(2)(ix) Examination of Metal Containments and the
Liners of Concrete Containments (Current); 10 CFR 50.55a(b)(2)(v)
(Redesignated)
The NRC proposes to redesignate Sec. 50.55a(b)(2)(ix) as Sec.
50.55a(b)(2)(v). This paragraph stipulates the conditions that apply to
the inservice examination of metal containments and liners of concrete
containments using Subsection IWE of various editions and addenda of
the ASME B&PV Code, Section XI, incorporated by reference in Sec.
50.55a(b)(2). The NRC proposes to remove the conditions in newly
redesignated Sec. 50.55a(b)(2)(v)(F), (b)(2)(v)(G), (b)(2)(v)(H) and
(b)(2)(v)(I) when applying the 2004 Edition with 2006 Addenda through
the 2007 Edition with 2008 Addenda of the ASME Code, Section XI because
these conditions have now been incorporated into the Code. The NRC
further proposes to remove the condition in redesignated Sec.
50.55a(b)(2)(v)(I) when applying the 2004 Edition, up to and including,
the 2005 Addenda. The NRC also proposes to add a new condition as Sec.
50.55a(b)(2)(v)(J) on the use of Article IWE-5000 of Subsection IWE
when applying the 2007 Edition, up to and including the 2008 Addenda of
the ASME Code, Section XI. These proposed changes are further explained
in this document.
The current regulations, in part, require that licensees applying
Subsection IWE, 1998 Edition through the 2004 Edition apply the
conditions in Sec. 50.55a(b)(2)(ix)(A), (b)(2)(ix)(B), and
(b)(2)(ix)(F) through (b)(2)(ix)(I). In the proposed rule, the
conditions in newly redesignated Sec. 50.55a(b)(2)(v)(F) through
(b)(2)(v)(I) would remain applicable to licensees applying Subsection
IWL, 1998 Edition through the 2001 Edition with the 2003 Addenda. As a
minor correction to the current regulations, the proposed rule would
require that licensees applying Subsection IWE of the 2004 Edition
through the 2005 Addenda of the ASME B&PV Code, satisfy the
requirements of newly redesignated Sec. 50.55a(b)(2)(v)(A),
(b)(2)(v)(B), and (b)(2)(v)(F) through (b)(2)(v)(H). This correction is
being made since paragraph IWE-3511.3 of the 2004 Edition of the ASME
B&PV Code incorporated the condition in newly redesignated Sec.
50.55a(b)(2)(v)(I), which requires that the ultrasonic examination
acceptance standard specified in IWE-3511.3 for Class MC pressure-
retaining components must also be applied to metallic liners of Class
CC pressure-retaining components. Further, the proposed rule would
require that licensees applying Subsection IWE, 2004 Edition with the
2006 Addenda through the latest edition and addenda incorporated by
reference in Sec. 50.55a(b)(2) satisfy the requirements of newly
redesignated Sec. 50.55a(b)(2)(v)(A) and (b)(2)(v)(B). This is because
the intent of the conditions in newly redesignated Sec.
50.55a(b)(2)(v)(F) through (b)(2)(v)(H) were incorporated into
Subsection IWE, 2004 Edition with the 2006 addenda, and the condition
in newly redesignated Sec. 50.55a(b)(2)(v)(I) was incorporated into
Subsection IWE, 2004 Edition, as explained in this document.
The condition in redesignated Sec. 50.55a(b)(2)(ix)(F) of the
proposed rule requires that VT-1 and VT-3 examinations be conducted in
accordance with IWA-2200. Personnel conducting examinations in
accordance with the VT-1 or VT-3 examination method must be qualified
in accordance with IWA-2300, and the ``owner-defined'' personnel
qualification provisions in IWE-2330(a) for personnel that conduct VT-1
and VT-3 examinations are not approved for use. This condition defines
the code provision (IWA-2200) and personnel qualification (IWA-2300)
requirements for personnel performing visual examinations by the VT-1
or VT-3 method, as specified in the conditions in redesignated Sec.
50.55a(b)(2)(v)(G) and (b)(2)(v)(H) of the proposed rule. The condition
does not allow use of the ``owner-defined'' personnel qualification
provisions in IWA-2330(a) for personnel that conduct VT-1 and VT-3
examinations. The revised code provision in IWE-2330(a) of the 2006
Addenda requires that personnel performing VT-1 and VT-3 visual
examinations shall meet the qualification requirements of IWA-2300. The
revised code provision in IWL-2100 of the 2006 Addenda states that IWA-
2000 applies with the exception that IWA-2210 and IWA-
[[Page 24336]]
2300 do not apply to general visual examination only (except as
required by 2330(b) for vision test requirements). Therefore, the code
provisions in IWA-2200 and IWA-2300 will apply to VT-1 and VT-3
examinations. Thus, the revised code provisions in IWE-2330(a) and IWE-
2100 of the 2006 through 2008 Addenda fully incorporates the condition
in newly redesignated Sec. 50.55a(b)(2)(v)(F). Therefore, the
condition in newly redesignated Sec. 50.55a(b)(2)(v)(F) is not
required to be applied for licensees using Subsection IWE, 2004 Edition
with the 2006 Addenda and the 2007 Edition through the 2008 Addenda.
The condition in redesignated Sec. 50.55a(b)(2)(v)(G) of the
proposed rule requires that the VT-3 examination method be used to
conduct the examinations in Items E1.12 and E1.20 of Table IWE 2500-1,
and the VT-1 examination method be used to conduct the examination in
Item E4.11 of Table IWE-2500-1. An examination of the pressure-
retaining bolted connections in Item E1.11 of Table IWE-2500-1 using
the VT-3 examination method must be conducted once each interval. The
``owner-defined'' visual examination provisions in IWE-2310(a) are not
approved for use for VT-1 and VT-3 examinations. This condition,
applicable in the current regulations to the 1998 Edition through the
2004 Edition, requires that the VT-3 and VT-1 examination methods be
used in lieu of the ``General Visual'' and ``Detailed Visual'' methods,
respectively, as specified in Table IWE-2500-1 for the Item Numbers
listed in the condition, and that the owner-defined visual examination
provisions in IWE-2310(a) cannot be used for VT-1 and VT-3
examinations. In the 2006 Addenda through the 2008 Addenda, Table IWE-
2500-1 was revised to change the examination method for Item Numbers
E1.12 and E1.20 to the VT-3 method and for Item E4.11 to the VT-1
method. Also, a new Examination Category E-G was added for pressure-
retaining bolting with Item No. E8.10 which requires 100 percent of
each bolted connection to be examined, using the VT-1 method and the
acceptance standard in the newly added paragraph IWE-3530, once during
each Inspection Interval with the connection assembled and bolting in-
place, provided the connection is not disassembled during the interval,
or in the disassembled configuration if the connection is disassembled
for any reason during the interval. This VT-1 examination, which is
more stringent than the VT-3 method specified in the condition, is in
addition to the general visual examination of 100 percent of the
pressure-retaining bolted connections during each inspection period
required to be performed under Item No. E1.11 of Table IWE-2500-1.
Further, the revised IWL-2310 does not have any owner-defined
provisions for performing visual examinations including VT-1 and VT-3
examinations. Thus, the provisions in the revised Table IWE-2500-1 and
the revised paragraph IWE-2310 addressed the intent of the condition in
newly redesignated Sec. 50.55a(b)(2)(v)(G). Therefore, the condition
in newly redesignated Sec. 50.55a(b)(2)(v)(G) is not required to be
applied for licensees using Subsection IWE, 2004 Edition with the 2006
Addenda and the 2007 Edition through the 2008 Addenda.
The condition in redesignated Sec. 50.55a(b)(2)(v)(H) of the
proposed rule requires that containment bolted connections that are
disassembled during the scheduled performance of the examinations in
Item E1.11 of Table IWE-2500-1 be examined using the VT-3 examination
method. Flaws or degradation identified during the performance of a VT-
3 examination must be examined in accordance with the VT-1 examination
method, and the criteria in the material specification or IWB 3517.1
must be used to evaluate containment bolting flaws or degradation. As
an alternative to performing VT-3 examinations of containment bolted
connections that are disassembled during the scheduled performance of
Item E1.11, VT-3 examinations of containment bolted connections may be
conducted whenever containment bolted connections are disassembled for
any reason. The condition in newly redesignated Sec.
50.55a(b)(2)(v)(H) is similar to the condition for bolted connections
in newly redesignated Sec. 50.55a(b)(2)(v)(G), but applies only to
examination of pressure-retaining bolted connections that are
disassembled. The condition requires flaws or degradation identified
during the VT-3 examination to be examined using the VT-1 method. The
NRC notes that the VT-1 (and not VT-3) examination method is the method
specified in the new Item E8.10 for pressure-retaining bolted
connections in the revised Table IWE-2500-1 in the 2006 Addenda through
2008 Addenda of the ASME B&PV Code. Further, the acceptance standard
for the VT-1 examination of pressure-retaining bolting in the new
paragraph IWE-3530 requires that the relevant conditions, as defined in
IWA-9000, and listed in IWB-3517.1, shall be corrected or evaluated to
meet the requirements of IWE-3122, prior to continued service.
Therefore, the new provision for pressure-retaining bolting in Table
IWE 2500-1, as discussed in this document, and the new acceptance
standard specified in IWE-3530, as discussed in this document, fully
addressed the intent of the condition in newly redesignated Sec.
50.55a(b)(2)(v)(H). Therefore, the condition in newly redesignated
Sec. 50.55a(b)(2)(v)(H) is not required to be applied for licensees
using Subsection IWE, 2004 Edition with the 2006 Addenda and the 2007
Edition through the 2008 Addenda.
The condition in redesignated Sec. 50.55a(b)(2)(ix)(I) of the
proposed rule requires that the ultrasonic examination acceptance
standard specified in IWE-3511.3 for Class MC pressure-retaining
components also be applied to metallic liners of Class CC pressure-
retaining components. This condition requires that the acceptance
standard in IWE-3511.3 also apply to the metallic shell and penetration
liners of Class CC pressure-retaining components in the re-designated
paragraph IWE-3522, ``Ultrasonic Examination,'' in the 2004 Edition
through the 2007 Edition and 2008 Addenda. Therefore, the condition in
newly redesignated Sec. 50.55a(b)(2)(v)(I) is not required to be
applied for licensees using Subsection IWE, 2004 Edition through the
2007 Edition and the 2008 Addenda.
Although the revised paragraph IWE-2310 (IWE-2313 to be specific)
and new subparagraphs IWE-2420(c) and IWE-2500(d), in the 2006 Addenda
through the 2008 Addenda, address the condition in newly redesignated
Sec. 50.55a(b)(2)(v)(A) of the proposed rule with regard to requiring
evaluation of acceptability of inaccessible areas when conditions
exists in accessible areas that could indicate the presence or result
in degradation to such inaccessible areas, the NRC has retained the
condition in the proposed rule, since the information specified in the
condition to be provided in the ISI Summary Report are not explicitly
addressed in the ASME B&PV Code.
10 CFR 50.55a(b)(2)(v)(J) (New)
The NRC proposes to add a new Sec. 50.55a(b)(2)(v)(J) to place a
condition on the use of Article IWE-5000, ``System Pressure Tests,'' of
Subsection IWE when applying the 2007 Edition up to and including the
2008 Addenda of the ASME Code, Section XI. The revised Article IWE-5000
does not make a distinction between ``major'' and ``minor''
modification (or repair/replacement) with regard to the type of
pneumatic leakage tests specified following repair/replacement
activities. It requires a pneumatic leakage test to be performed
[[Page 24337]]
following welding or brazing associated with repair or replacement
activities, prior to returning the component to service. However, it
allows a licensee the option of only performing a local bubble test
even for a ``major'' containment modification or repair/replacement.
Following ``major'' containment repair/replacement activities, it makes
the performance of the appropriate pneumatic leakage test (which is a
Type A test) in accordance with 10 CFR part 50, appendix J, optional,
and hence the NRC proposes to add a new condition in this rule. It is
the NRC's position that a 10 CFR part 50, appendix J, Type A test or
alternatively, a short duration structural test, must be performed
following a ``major'' containment modification or repair/replacement,
prior to returning the containment to operation. This is because a
``major'' containment modification such as the replacement of a large
penetration or the creation of large construction opening(s) for
equipment replacement results in the breach of the containment pressure
boundary that invalidates the periodic verification of structural and
leak tight integrity provided by the previous Type A test as required
by the Containment Leakage Rate Testing Program in 10 CFR part 50,
appendix J. Further, the breach of pressure boundary of the magnitude
resulting from a ``major'' containment modification has a global effect
on containment structural integrity and not a localized effect.
Therefore, performing a Type A test or an alternate short duration
structural test, prior to returning to operation, is necessary to
provide a reasonable assurance and verification of containment
structural and leakage integrity following restoration of a breach in
the containment pressure boundary due to a ``major'' repair/replacement
activity. Thus, the new condition in Sec. 50.55a(b)(2)(v)(J) of the
proposed rule will require the performance of Type A test, or short
duration structural test, following a ``major'' containment
modification.
The proposed new condition would provide a general, qualitative
definition of what constitutes a ``major'' modification or repair/
replacement activity for containments. The proposed condition would
also define the combination of actions that would constitute an
acceptable, alternate short-duration structural test that may be
performed in lieu of a Type A test following a major containment
modification. These proposed requirements to perform a Type A test, or
alternate short-duration structural test, following a ``major''
containment modification are consistent with the NRC's position and
condition in Section 4.1.4 and Section 3.1.4 of the Final Safety
Evaluation by the Office Of Nuclear Reactor Regulation dated June 25,
2008 (ADAMS No. ML081140105), on Topical Report NEI 94-01, Revision 2,
``Industry Guideline for Implementing Performance-Based Option of 10
CFR Part 50, Appendix J.'' The new condition would also require that,
when applying IWE-5000, if a Type A, B or C test is performed in
accordance with 10 CFR part 50, appendix J, the acceptance standard for
the test shall also be in accordance with 10 CFR part 50, appendix J.
This is because the acceptance standard for leakage in IWE-5223.5 is
based only on Section V, Article 10, for any pneumatic leakage test
performed when applying IWE-5000 of the 2007 Edition up to and
including the 2008 Addenda of Section XI of the ASME Code. The
requirement in the new condition for performing a Type A test or an
alternate short duration structural test, prior to returning to
operation following a major containment modification, is necessary to
provide a reasonable assurance and verification of containment
structural and leakage integrity following restoration of a breach in
the containment pressure boundary due to the ``major'' repair/
replacement activity.
10 CFR 50.55a(b)(2)(xv) Appendix VIII Specimen Set and Qualification
Requirements (Current); 10 CFR 50.55a(b)(2)(xi) (Redesignated)
The NRC proposes to redesignate Sec. 50.55a(b)(2)(xv) as Sec.
50.55a(b)(2)(xi) and revise the current regulations so the current
conditions in that paragraph would not apply to the 2007 Edition
through the 2008 Addenda of Section XI of the ASME B&PV Code. The
current regulation has conditions that may be used to modify Appendix
VIII of Section XI, 1995 Edition through the 2001 Edition. The ASME
Boiler and Pressure Vessel Code Committees took action to address these
conditions in the 2007 Edition of the Code and revised Appendix VIII to
address the NRC's concerns with specimen sets and qualification
requirements. Therefore, the conditions are not required when using the
2007 Edition through the 2008 Addenda of the ASME B&PV Code, and the
NRC is proposing that the current Sec. 50.55a(b)(2)(xv) should be
revised not to apply these conditions when using the 2007 Edition
through the 2008 Addenda of the ASME B&PV Code.
10 CFR 50.55a(b)(2)(xviii) Certification of NDE Personnel (Current); 10
CFR 50.55a(b)(2)(xiv) (Redesignated)
The NRC proposes to redesignate Sec. 50.55a(b)(2)(xviii)(B) as
Sec. 50.55a(b)(2)(xiv)(B) and revise the current regulations so the
current condition in that paragraph would not apply to the 2007 Edition
through the 2008 Addenda of Section XI of the ASME B&PV Code. Section
50.55a(b)(2)(xviii)(B) in the current regulations limits the activities
that can be performed by NDE personnel certified in accordance with
IWA-2316 of the 1998 Edition through the 2004 Addenda of the ASME B&PV
Code. These personnel are limited to observing for leakage during
system leakage and hydrostatic tests conducted in accordance with IWA-
5211(a) and (b). The ASME Boiler and Pressure Vessel Code Committees
took action to address this, and modified IWA 2316 in the 2005 Addenda
and the 2007 Edition to limit the activities performed by personnel
qualified in accordance with IWA-2316. Therefore, the condition is not
required when using the 2007 Edition through the 2008 Addenda.
Accordingly, the NRC is proposing that the current Sec.
50.55a(b)(2)(xviii)(B) be revised for this condition not to apply when
using the 2007 Edition through the 2008 Addenda of the ASME B&PV Code.
The NRC proposes to redesignate Sec. 50.55a(b)(2)(xviii)(C) as
Sec. 50.55a(b)(2)(xiv)(C) and revise the current requirement so the
current condition in that paragraph would not apply to the 2005 Addenda
through the 2008 Addenda of Section XI of the ASME B&PV Code. This
paragraph in the current regulations places conditions on the
qualification of VT-3 examination personnel certified under paragraph
IWA-2317 of the 1998 Edition through the 2004 Addenda. The regulation
requires the administering of an initial qualification examination to
demonstrate proficiency of this training, and administering subsequent
examinations on a 3-year interval. The ASME Boiler and Pressure Vessel
Code Committees took action to address this condition and modified IWA-
2317 in the 2005 Addenda of the ASME B&PV Code to require a written
examination for initial qualification and at least every 3 years
thereafter for VT-3 qualification. Therefore, the condition is not
required when using the 2005 Addenda through the 2008 Addenda.
[[Page 24338]]
10 CFR 50.55a(b)(2)(xix) Substitution of Alternative Methods (Current);
10 CFR 50.55a(b)(2)(xv) (Redesignated)
The NRC proposes to redesignate Sec. 50.55a(b)(2)(xix) as Sec.
50.55a(b)(2)(xv) and revise the current regulations so the current
conditions for the substitution of alternative examination methods in
that paragraph would not apply when using the 2005 Addenda through the
2008 Addenda. The conditions in current Sec. 50.55a(b)(2)(xix) do not
allow the use of Section XI, IWA 2240 of the 1998 Edition through the
2004 Edition of the ASME B&PV Code. These conditions also do not allow
the use of IWA-4520(c) of the 1997 Addenda through the 2004 Edition of
Section XI of the ASME B&PV Code. In 2005, the ASME Boiler and Pressure
Vessel Code Committees took action to address these conditions and
modified IWA-2240 and deleted IWA-4520(c) in the 2005 Addenda, such
that, alternative examination methods or newly developed techniques are
not allowed to be substituted for the methods specified in the
construction code. Therefore, these conditions are not required when
using the 2005 Addenda through the 2008 Addenda.
In newly redesignated Sec. 50.55a(b)(2)(xv), the NRC is also
proposing to impose the condition that paragraphs IWA-4520(b)(2) and
IWA-4521 of the 2007 Edition of Section XI, Division 1, of the ASME
B&PV Code, with the 2008 Addenda are not approved for use. In the 2008
Addenda of Section XI of the ASME B&PV Code, the ASME added new
provisions in IWA 4520(b)(2) and IWA-4521 that allow the substitution
of ultrasonic examination (UT) for radiographic examination (RT)
specified in the Construction Code. Substitution of UT for RT as
addressed in paragraph IWA-4520(b)(2) of the ASME B&PV Code, Section
XI, for the repair/replacement welds in 2008 Addenda is of a concern to
the NRC because, depending on flaw type (i.e., volumetric or planar)
and orientation, UT and RT are not equally effective for flaw detection
and characterization. The NRC had originally identified concerns
relative to the calibration blocks to be used, and developed two
conditions that appear in Regulatory Guide 1.84, ``Design, Fabrication,
and Materials Code Case Acceptability, ASME Section III, Proposed
Revision 34.''
RT is effective in detecting volumetric-type flaws (e.g., slag,
porosity, root concavity, and misalignment), planar type flaws with
large openings (e.g., lack of fusion and large cracks in high stressed
areas), and those flaws that are oriented in a plane parallel to the X-
ray beam. RT is effective in all materials common to the nuclear
industry for detecting the type of flaws generated during construction,
due to workmanship issues and, therefore, ensures an acceptable level
of weld quality and safety at the time of construction. In contrast, UT
is most effective in detecting and sizing planar-type flaws associated
with inservice degradation due to, for example, fatigue or stress
corrosion cracking. Significant advances have recently been made
regarding the use of UT to detect flaws in cast stainless steel.
However, the ASME Code provisions addressing the inspection of cast
stainless steels are still under development and are, therefore, not
yet published for use. Finally, UT requires more surface scanning area
than RT to perform examinations.
To ensure that a UT technique would be capable of detecting typical
construction flaws, the NRC would require a licensee to demonstrate,
through performance-based ASME B&PV Code, Section XI, Appendix VIII-
like requirements, its capability of identifying the construction flaws
which are easily detected by RT. Performance-based qualifications
require demonstrations on mockups having flaws with realistic UT
responses and with a statistically sufficient number of representative
flaws and non-flawed volumes to establish procedure effectiveness and
personnel skill. The statistical approach to qualification has been
shown to improve the reliability of inspections, to improve the
probability of flaw detection, and to reduce the number of false calls.
The addition of only two or three construction flaws to a demonstration
is not sufficient to capture the variety of flaws common to
construction or to statistically evaluate procedure effectiveness and
personnel skills.
The NRC is concerned that using the second leg of the ultrasound
metal path (V-path) to achieve two direction scanning from only one
side of the weld may not be adequate in detecting construction flaws.
Single side examinations have not been demonstrated for construction
flaws for any material. Single side examinations of welds have been
successfully qualified for planar flaws in ferritic carbon and low
alloy steels but have not been reliably demonstrated for austenitic
stainless steel and nickel alloys.
Based on this information, the NRC concludes that the substitution
of UT for RT may not be adequate for detecting some construction flaws,
specifically in single-V full penetration groove welds. Therefore,
substitution of UT for RT is not generically acceptable. This position
is consistent with the NRC's previous position with respect to the
review of ASME Code Case N-659-1, which is published in Regulatory
Guide 1.193, Revision 2, ``ASME Code Cases not Approved for Use.''
Accordingly, the NRC proposes to impose the condition that paragraphs
IWA-4520(b)(2), and IWA-4521 of the 2007 Edition of Section XI,
Division 1, with 2008 Addenda are not approved for use.
10 CFR 50.55a(b)(2)(xxiv) Incorporation of the Performance
Demonstration Initiative and Addition of Ultrasonic Examination
Criteria (Current); 10 CFR 50.55a(b)(2)(xx) (Redesignated)
The NRC proposes to redesignate Sec. 50.55a(b)(2)(xxiv) as Sec.
50.55a(b)(2)(xx) and revise the current regulations not to apply the
current condition when using the 2007 Edition through the 2008 Addenda.
Current Sec. 50.55a(b)(2)(xxiv) prohibits the use of Appendix VIII,
the supplements of Appendix VIII and Article I-3000 of ASME B&PV Code,
2002 Addenda through the 2004 Edition. In 2007, the ASME Boiler and
Pressure Vessel Code Committees took action to address this condition
and modified Appendix VIII and its Supplements in the 2007 Edition.
Therefore, the condition is not required when using the 2007 Edition
through the 2008 Addenda, and the NRC proposes to eliminate this
condition when using the 2007 Edition through the 2008 Addenda.
10 CFR 50.55a(b)(2)(xxvii) Removal of Insulation (Current); 10 CFR
50.55a(b)(2)(xxii) (Redesignated)
The NRC proposes to redesignate Sec. 50.55a(b)(2)(xxvii) as Sec.
50.55a(b)(2)(xxiii) and revise the paragraph to refer to IWA-5242 of
the 2003 Addenda through the 2006 Addenda or IWA-5241 of the 2007
Edition through the 2008 Addenda of Section XI of the ASME B&PV Code
for performing VT-2 visual examination of insulated components in
systems borated for the purpose of controlling reactivity. The current
regulations at Sec. 50.55a(b)(2)(xxvii) place specific requirements on
when insulation must be removed to visually examine insulated
components in accordance with IWA-5242. In the 2007 Edition of the ASME
B&PV Code, Section XI, paragraph IWA-5242 was deleted and these
requirements were included in paragraph IWA-5241.
[[Page 24339]]
10 CFR 50.55a(b)(2)(xxiv) Analysis of Flaws (New)
The NRC proposes to add a new Sec. 50.55a(b)(2)(xxiv) to place
conditions on the use of Section XI, Nonmandatory Appendix A,
``Analysis of Flaws.'' The proposed regulation would place a condition
on the use of Appendix A related to the fatigue crack growth rate
calculation for subsurface flaws defined in paragraph A-4300(b)(1) when
the ratio of the minimum cyclic stress to the maximum cyclic stress (R)
is less than zero. The fatigue crack growth rate, da/dN, is defined as
follows when using Equation (1) in paragraph A-4300(a) and Equation (2)
in paragraph A-4300(b)(1):
da/dN = 1.99 x 10-10 S
([Delta]KI)3.07, where S is a scaling
parameter and [Delta]KI is the range of applied stress
intensity factor
S and [Delta]KI are defined in A-4300(b)(1) of the ASME
B&PV Code, Section XI, Appendix A as follows:
For -2 <= R <= 0 and Kmax-Kmin <= 1.12
[sigma]f [radic]([pi]a), S = 1 and [Delta]KI =
Kmax
For R < -2 and Kmax-Kmin <= 1.12
[sigma]f [radic]([pi]a), S = 1 and [Delta]KI =
(1-R) Kmax/3
For R < 0 and Kmax-Kmin > 1.12
[sigma]f [radic]([pi]a), S = 1 and [Delta]KI =
Kmax--Kmin
The above guidelines permit reduction of [Delta]KI from
the value of (Kmax-Kmin) when Kmax-
Kmin <= 1.12 [sigma]f [radic]([pi]a). This is
adequate if the material property [sigma]f is from test-
based data of the component material and if the geometry of the cracked
component can be modeled as an edge crack in a half plane, so that the
formula K = 1.12 [sigma] [radic]([pi]a) applies. In most ASME B&PV
Code, Section XI, Appendix A applications, test-based
[sigma]f is not available, and the generic value from the
ASME B&PV Code tabulations is used. Further, the geometry of a
subsurface flaw in a plate differs significantly from the model of an
edge crack in a half plane. Consequently, for the case where full
[Delta]KI should be used, the calculation in accordance with
ASME B&PV Code, Section XI, Appendix A may show that Kmax-
Kmin <= 1.12 [sigma]f [radic]([pi]a) and prompt a
wrongful reduction of [Delta]KI.
To address the use of the generic [sigma]f value instead
of the test-based value for the cracked component and the significant
difference between the cracked component geometry and the cracked test-
specimen geometry on which the criterion of 1.12 [sigma]f
[radic]([pi]a) is derived, the NRC proposes to revise the criterion of
1.12 [sigma]f [radic]([pi]a) to 0.8 times 1.12
[sigma]f [radic]([pi]a). By doing so, reduction of
[Delta]KI will not take place during the range of
Kmax-Kmin from 0.8 x1.12 [sigma]f
[radic]([pi]a) to 1.12 [sigma]f [radic]([pi]a), erasing the
non-conservatism from the two sources mentioned above. Selection of a
multiplying factor of 0.8 is based on the following:
The 10 percent error that could be introduced for the
subsurface flaw configurations having membrane stress correction
factors less than 1.12 as indicated in Appendix A, Figure A-3310-1, and
Another 10-percent error that accounts for the uncertainty
in the [sigma]f value.
Applying the revised criterion of 0.8 x 1.12 [sigma]f
[radic]([pi]a), results in the proposed following condition on the use
of the fatigue crack growth rate calculation for subsurface flaws
defined in paragraph A-4300(b)(1) of Section XI, Nonmandatory Appendix
A when R is less than zero:
da/dN = 1.99 x 10-10 S ([Delta]KI)\3.07\
For R < 0, [Delta]KI depends on the crack depth, a, and
the flow stress, [sigma]f. The flow stress is defined by
[sigma]f = \1/2\([sigma]ys +
[sigma]ult), where [sigma]ys is the yield
strength and [sigma]ult is the ultimate tensile strength
in units ksi (MPa) and a is in units in. (mm).
For -2 <= R <= 0 and Kmax-Kmin <= 0.8 x 1.12
[sigma]f [radic]([pi]a), S = 1 and [Delta]KI =
Kmax.
For R < -2 and Kmax-Kmin <= 0.8 x 1.12
[sigma]f [radic]([pi]a), S = 1 and [Delta]KI =
(1-R) Kmax/3.
For R < 0 and Kmax-Kmin > 0.8 x 1.12
[sigma]f [radic]([pi]a), S = 1 and [Delta]KI =
Kmax-Kmin.
10 CFR 50.55a(b)(2)(xxv) Evaluation of Unanticipated Operating Events
(New)
The NRC proposes to add a new Sec. 50.55a(b)(2)(xxv) to condition
the use of ASME B&PV Code, Section XI, Nonmandatory Appendix E,
``Evaluation of Unanticipated Operating Events.'' Appendix E provides
acceptance criteria and guidance evaluating the effects of out-of-limit
conditions on structural integrity of the reactor vessel beltline
region. The NRC proposes to specify that Section E-1200 is not
acceptable, and to set forth two conditions on the use of Section E-
1300. One proposed condition would require that a 1/4T flaw be used in
the linear elastic fracture mechanics (LEFM) evaluation with a margin
of 1.4 applying to KIm in the two LEFM criteria. The other
proposed condition would also use KIc instead of
KIR in the Appendix E analysis.
Appendix E of the ASME B&PV Code, Section XI, addresses the
evaluation of the structural integrity of the reactor pressure vessel
(RPV) after an out-of-limit condition occurs using LEFM based on a
postulated surface flaw. The underlying Appendix E methodology is based
on the following two LEFM criteria:
1.6(KIm) + KIr = KIc for the low
temperature overpressure (LTOP) condition
1.6(KIm + KIt) + KIr =
KIc, for the pressurized thermal transient (PTT)
condition
Where KIm, KIr, and KIt are the
applied primary, residual, and thermal stresses, respectively, and
KIc is plane-strain fracture toughness. Both are based on
a postulated flaw of 1-inch in depth. The details regarding these
criteria are documented in the Electric Power Research Institute's
(EPRI) report NP-5151, ``Evaluation of Reactor Vessel Beltline
Integrity Following Unanticipated Operating Events,'' dated April
1987. The justification for selecting the 1-inch deep flaw is given
in the EPRI report as follows:
The crack size range has an upper limit of one inch. Experience
shows that the fabrication practice and inspection requirements for
nuclear pressure vessels generally preclude the undetected presence
of larger flaws.
The above qualitative justification for selecting the 1-inch depth
for the postulated flaw is not sufficient. The ASME B&PV Code, Section
XI, Appendix G, ``Fracture Toughness Criteria for Protection Against
Failure,'' analysis, which can be considered as the first ``screening''
criterion for safe operation of an RPV, is based on a postulated flaw
of one-quarter of the RPV wall thickness (1/4T). The Section XI,
Appendix E analysis is employed when the ASME B&PV Code, Appendix G
requirements are exceeded due to an out-of-limit condition. Hence, it
is considered as the second ``screening'' criterion, i.e., once
satisfied, a refined analysis or a special RPV inspection is not
needed. As the second screening tool, the Section XI, Appendix E
analysis has to be conservative. In addition, the following three
concerns prompt the NRC to propose the use of a 1/4T flaw in the
Appendix E, Section E-1300 analysis:
In the probabilistic fracture mechanics (PFM) analyses
supporting the proposed PTS rule, the truncated flaw depth for a repair
weld flaw is 2 inches. For a deterministic analysis, the possibility of
having a repair weld flaw line up with a clad flaw to become a surface
flaw cannot be ruled out.
The Pressure Vessel Research User's Facility (PVRUF) and
Shoreham RPV flaw data, used to develop generic flaw distributions for
the proposed PTS rule, identified flaws that were consistently smaller
than the proposed bounding flaw. However, the PVRUF and Shoreham data
represent only a limited sampling of all RPV welds and may not directly
provide an adequate bounding flaw size for a deterministic analysis
like that of ASME B&PV Code, Section XI, Appendix E.
The use of a 1/4T flaw assumption also provides additional
assurance that
[[Page 24340]]
any service-induced growth of current fabrication flaws will be bounded
for any RPVs having experienced severe transients over the course of
their operating lifetimes.
Requiring that a 1/4T flaw be used in the LEFM evaluation with a
margin of 1.4 applying to KIm in the two LEFM criteria
establishes a consistent approach regarding the postulated flaw size in
the two deterministic LEFM analyses in ASME B&PV Code, Section XI,
Appendices E and G. Applying the margin of 1.4 only to KIm
is consistent with the ASME B&PV Code, Section XI, Appendix G approach,
making the decreased margin between the two appendices traceable. The
proposed use of a smaller margin of 1.4 in the ASME B&PV Code, Section
XI, Appendix E analysis is justified because all significant stress
intensity factors resulting from an actual transient are considered.
Further, using a 1/4T flaw is also consistent with prior NRC approaches
for evaluation of RPV structural integrity after out-of-limit events.
The EPRI NP-5151 report mentioned that reference toughness
KIR has been used in the LEFM evaluation in the prior NRC
evaluation of RPV structural integrity after out-of-limit events.
Consistent with the evolution of the ASME B&PV Code, Section XI,
Appendix G analysis, the NRC now proposes to use KIc instead
of KIR in the ASME B&PV Code, Section XI, Appendix E
analysis.
10 CFR 50.55a(b)(2)(xxvi) Risk-Informed Inservice Inspection (New)
The NRC proposes to add a new condition in Sec. 50.55a(b)(2)(xxvi)
to condition the use of ASME B&PV Code, Section XI, Non-Mandatory
Appendix R, ``Risk-Informed Inspection Requirements of Piping.'' The
proposed condition would require licensees to submit an alternative in
accordance with Sec. 50.55a(a)(3) and obtain NRC authorization of the
proposed alternative prior to implementing Appendix R, RI-ISI programs.
The 2004 Edition of the ASME B&PV Code, Section XI currently
incorporated by reference in the regulations did not contain provisions
for Risk-Informed Inservice Inspection (RI-ISI). The 2005 Addenda
introduced Non-Mandatory Appendix R into Section XI to provide risk-
informed requirements for the ISI of ASME B&PV Code Class 1, 2 and 3
piping. The addition of Appendix R to Section XI was essentially the
incorporation of ASME Code Cases N-577 and N-578 into the ASME B&PV
Code. The NRC determined that ASME Code Cases N-577 and N-578 were
unacceptable for use and are currently listed in Regulatory Guide
1.193,''ASME Code Cases Not Approved for Use,'' Revision 2. Licensees
have been implementing RI-ISI requirements for piping as an alternative
to the ASME B&PV Code, Section XI requirements of Tables IWB-2500-1,
IWC-2500-1 and IWD-2500-1 submitted in accordance with Sec.
50.55a(a)(3). Adding a condition as Sec. 50.55a(b)(2)(xxvi) that would
require licensees to submit an alternative in accordance with Sec.
50.55a(a)(3) and obtain NRC authorization of the proposed alternative
prior to implementing Appendix R, RI-ISI programs would ensure that
future RI-ISI programs continue to comply with RG 1.178, ``An Approach
for Plant-Specific Risk-Informed Decisionmaking for Inservice
Inspection of Piping,'' RG1.200, ``An Approach for Determining the
Technical Adequacy of Probabilistic Risk Assessment Results for Risk-
Informed Activities,'' and NRC Standard Review Plan 3.9.8, ``Risk-
Informed Inservice Inspection of Piping.''
ASME OM Code
The proposed amendment would revise the introductory text in Sec.
50.55a(b)(3) to incorporate by reference the 2005 and 2006 Addenda of
the ASME OM Code into 10 CFR 50.55a. The proposed amendment to Sec.
50.55a(b)(3) would also clarify that Subsections ISTA, ISTB, ISTC, and
ISTD, Mandatory Appendices I and II, and Nonmandatory Appendices A
through H and J of the ASME OM Code would be incorporated by reference.
The conditions in Sec. 50.55a(b)(3)(i), (b)(3)(ii), and (b)(3)(iv)
would continue to apply to the 2005 and 2006 Addenda because the
earlier ASME B&PV Code provisions that these regulations are based on
were not revised in the 2005 and 2006 Addenda of the ASME B&PV Code to
address the underlying issues which led the NRC to impose the
conditions on the ASME B&PV Code.
The NRC proposes to revise the current requirements in Sec.
50.55a(b)(3)(v) to be consistent with the revised snubber ISI
provisions in the 2006 Addenda of the ASME B&PV Code, Section XI. To
accomplish this Sec. 50.55a(b)(3)(v) will be divided into Sec.
50.55a(b)(3)(v)(A) and Sec. 50.55a(b)(3)(v)(B). Where Sec.
50.55a(b)(3)(v)(A) allows licensees using editions and addenda up to
the 2005 Addenda of ASME Section XI to optionally use Subsection ISTD,
ASME OM Code in place of the requirements for snubbers in Section XI.
Section 50.55a(b)(3)(v)(B) would require licensees using the 2006
Addenda and later editions and addenda of Section XI to follow the
requirements of Subsection ISTD of the ASME OM Code for snubbers.
Provisions for the ISI of snubbers have been in Subsection ISTD since
the ASME OM Code was first issued in 1990.
10 CFR 50.55a(b)(3)(v) Subsection ISTD
The current requirement in Sec. 50.55a(b)(3)(v) allows licensees
using editions and addenda up to the 2004 Edition of the ASME B&PV
Code, Section XI to optionally use Subsection ISTD, ASME OM Code in
place of the requirements for snubbers in Section XI, and states that
snubber preservice and inservice examinations must be performed using
the VT-3 visual examination method when using Subsection ISTD of the
ASME OM Code. The NRC previously imposed this requirement to ensure
that an appropriate visual examination method was used for the
inspection of integral and non-integral snubber attachments, such as
lugs, bolting, and clamps when using Subsection ISTD of the ASME OM
Code. The proposed Sec. 50.55a(b)(3)(v)(A) allows licensees using
editions and addenda up to the 2005 Addenda of ASME B&PV Code, Section
XI to optionally use Subsection ISTD, ASME OM Code in place of the
requirements for snubbers in Section XI and continues to invoke the VT-
3 requirement. This option does not apply when using the 2006 Addenda
and later editions and addenda of Section XI of the ASME B&PV Code.
Figure IWF-1300-1 was revised in the 2006 Addenda of Section XI to
clarify that integral and non-integral snubber attachments are in the
scope of Section XI. Therefore, the visual examination method specified
in the 2006 Addenda and later editions and addenda of Section XI
applies to the examination of integral and non-integral snubber
attachments. The proposed Sec. 50.55a(b)(3)(v)(B) would require
licensees using the 2006 Addenda and later editions and addenda of
Section XI to follow the requirements of Subsection ISTD of the ASME OM
Code for snubbers.
10 CFR 50.55a(b)(3)(vi) Exercise Interval for Manual Valves
The NRC proposes to revise the current requirement for exercising
manual valves in Sec. 50.55a(b)(3)(vi) to limit its application to the
1999 through 2005 Addenda of the ASME OM Code. The current requirement
would not apply to the 2006 Addenda of the ASME OM Code because the
earlier ASME OM Code provision that this regulation was based on was
revised in the 2006
[[Page 24341]]
Addenda of the ASME OM Code to address the underlying issue which led
to the NRC to impose the condition. The exercise interval in Subarticle
ISTC-3540 for manually operated valves was revised in the 2006 Addenda
of the ASME OM Code to be the same as the current requirement in Sec.
50.55a(b)(3)(vi).
Reactor Coolant Pressure Boundary, Quality Group B Components, and
Quality Group C Components
The NRC proposes to revise Sec. 50.55a(c)(3), (d)(2), and (e)(2)
to replace ``but--'' with ``subject to the following conditions'' at
the end of the introductory text to each paragraph for clarity.
Inservice Testing Requirements
10 CFR 50.55a(f)(5)(iv) Requests for Relief
The NRC proposes to modify the wording of Sec. 50.55a(f)(5)(iv) to
clarify that licensees are required to submit requests for relief based
on impracticality within 12 months after the expiration of the IST
interval for which relief is being sought. Section 50.55a(f)(5)(iv) in
the current regulations describes the licensee's responsibility to
demonstrate to the satisfaction of the NRC those items determined to be
impractical and discusses the timeframe for this determination. The NRC
proposes to clarify Sec. 50.55a(f)(5)(iv) to more clearly articulate
the requirements for licensee action when compliance with certain code
requirements is determined to be impractical. Licensees have
interpreted the current language in Sec. 50.55a(f)(5)(iv) in a number
of ways, especially regarding NRC approval of their submittal within
the specified timeframe. Since the licensee has little or no control
over the timeliness of NRC action on their submittal, this
interpretation is problematic.
Inservice Inspection Requirements
Snubber Examination and Testing
The current requirements at Sec. 50.55a(g)(2), (g)(3)(i),
(g)(3)(ii), the introductory text of (g)(4), and (g)(4)(i) and
(g)(4)(ii) reference Section XI of the ASME B&PV Code for component
support ISI (including snubber examination and testing) provisions. The
current requirement at Sec. 50.55a(b)(3)(v) allows licensees the
option of using Subsection ISTD of the ASME OM Code in lieu of the ISI
provisions for snubbers in Article IWF-5000 of Section XI. When using
the 2005 Addenda to Section XI, Article IWF-5000 is required to be used
with the option to use OM Code Subsection ISTD noted. In the 2006
Addenda and later editions and addenda of Section XI, the snubber
requirements in Article IWF-5000 no longer exist because Article IWF-
5000 was deleted in the 2006 Addenda of Section XI. Therefore, the
proposed amendment would revise Sec. 50.55a(b)(3)(v) to require that
licensees use the provisions for examination and testing snubbers in
Subsection ISTD of the ASME OM Code when using the 2006 Addenda and
later editions and addenda of Section XI.
The NRC proposes to revise the current regulations in Sec.
50.55a(g)(2), (g)(3)(i), (g)(3)(ii), (g)(4)(i) and (g)(4)(ii) to
require that licensees use the provisions for preservice and inservice
examination and testing of snubbers in Subsection ISTD of the ASME OM
Code when using the 2006 Addenda and later edition of Section XI.
Licensees may also use optional code cases in RG 1.192 as approved by
the NRC. The NRC proposes to clarify that preservice examination may
meet preservice examination requirements in Section III as an
alternative to preservice examination of Section XI. The NRC also
proposes to revise the current regulation in the introductory text of
Sec. 50.55a(g)(4) to require that licensees using the ASME OM Code
follow the provision in Subsection ISTD for examination and testing of
snubbers. Provisions for examinations and tests of snubbers have been
in Article IWF-5000 since Subsection IWF was first issued in the Winter
1978 Addenda of Section XI. Article IWF-5000 was deleted in the 2006
Addenda of Section XI. Subarticle IWF-1220 in the 2006 Addenda of
Section XI states that the examination and testing requirements for
snubbers are now outside the scope of Section XI, and that the
examination and test requirements for snubbers can be found in
Subsection ISTD of the ASME OM Code. Provisions for the examination and
testing of snubbers have been in Subsection ISTD since the ASME OM Code
was first issued in 1990.
10 CFR 50.55a(g)(4)(iii) Surface Examinations of High-Pressure Safety
Injection Systems
The current regulations at Sec. 50.55a(g)(4)(iii) give licensees
the option of not performing surface examinations of high-pressure
safety injection systems as specified in Section XI, Table IWB-2500-1,
``Examination Category B-J,'' Item Numbers B9.20, B9.21 and B9.22.
Later editions and addenda of Section XI have been modified and the
surface examination requirement no longer exists in Table IWB-2500-1,
and some of the Item Numbers have either changed or been deleted. The
surface examination requirement was remove from Table IWB-2500-1 in the
2003 Addenda. Therefore, the paragraph needs to be revised for this
condition to apply to those licensees using Code editions and addenda
prior to the 2003 Addenda.
10 CFR 50.55a(g)(5)(iii) and (g)(5)(iv) Inservice Inspection Requests
for Relief
Section 50.55a(g)(5)(iii) currently requires the licensee to notify
the NRC if compliance with certain code requirements are found to be
impractical. The NRC proposes to add a sentence to Sec.
50.55a(g)(5)(iii) to clarify that a request for relief must be
submitted to the NRC no later than 12 months after the examination has
been attempted during a given ISI interval and the ASME B&PV Code
requirement determined to be impractical. In the past, licensees have
submitted requests under Sec. 50.55a(g)(5)(iii) prior to performing
the ASME B&PV Code examination in a given interval based on limited
examination coverage from previous ISI 10-year intervals. The NRC has
concluded that this is an inappropriate basis for a determination of
impracticality as new examination techniques are often developed from
one interval to the next, which could result in a reasonable
expectation of improved results. As a result, the NRC has concluded
that a licensee usually cannot make the determination that an
examination is indeed impractical without first attempting the
examination in the current ISI interval.
In addition, if the NRC were to grant relief prior to the component
having been examined and the results of the examination are less than
stated in the request for relief, the licensee would be required to
resubmit the request for relief to address the actual examination. This
places an unnecessary burden on the licensee and the NRC to review the
same issue twice. The proposed amendment to the regulations attempts to
clarify that the determination of impracticality should be based on
actual attempts to perform a requirement and only submitted after the
attempt to perform a requirement has been unsuccessful.
The NRC proposes to modify the wording of Sec. 50.55a(g)(5)(iv) to
clarify that licensees are required to submit requests for relief based
on impracticality within 12 months after the expiration of the ISI
interval for which relief is being sought. Section 50.55a(g)(5)(iv) in
the current regulations describe the licensee's responsibility to
demonstrate to the satisfaction of the NRC those items
[[Page 24342]]
determined to be impractical and discusses the timeframe for this
determination. The NRC proposes to clarify Sec. 50.55a(g)(5)(iv) to
more clearly articulate the requirements for licensee action when
compliance with certain code requirements is determined to be
impractical. It is the NRC's experience that licensees have interpreted
the current language in Sec. 50.55a(g)(5)(iv) in a number of ways,
especially regarding NRC approval of their submittal within the
specified timeframe. Since the licensee has little or no control over
the timeliness of NRC action on their submittal, this interpretation is
problematic.
10 CFR 50.55a(g)(6)(ii)(E) Reactor Coolant Pressure Boundary Visual
Inspections
The NRC proposes to update Sec. 50.55a(g)(6)(ii)(E)(1) through
(g)(6)(ii)(E)(3) to the requirements of Code Case N-722-1, and to
revise footnote 1 to clarify requirements in that paragraph that
pertain to reactor coolant pressure boundary visual inspections. In the
most recent update to 10 CFR 50.55a, the NRC added new requirements in
Sec. 50.55a(g)(6)(ii)(E). The new requirements were for all licensees
of PWRs to augment their ISI program by implementing ASME Code Case N-
722, subject to the conditions specified in Sec.
50.55a(g)(6)(ii)(E)(2) through (g)(6)(ii)(E)(4). ASME Code Case N-722-
1, ``Additional Examinations for PWR Pressure Retaining Welds in Class
1 Components Fabricated With Alloy 600/82/182 Materials Section XI,
Division 1,'' was published in Supplement 8 of the 2007 Edition of the
ASME Boiler and Pressure Vessel Code Nuclear Code Case book. This
revision of the code case contains one additional note which indicates
that visual examination of Alloy 600/82/182 materials in flange seal
leak-off lines is not required. This change will eliminate the need for
licensees to submit relief requests for flange seal leak-off lines
which are not normally exposed to a corrosive environment and are
inaccessible for visual examination.
The wording in the second sentence of footnote 1 to Sec.
50.55a(g)(6)(ii)(E) has generated some confusion, and has the
unintended consequence of some licensees believing that they need to
submit additional relief requests related to the percentage of
inspections to be completed during the current interval. The second
sentence in the footnote is intended to specify what portion of welds
has to be inspected during a plant interval that remains after January
1, 2009. The intent was to require licensees to distribute the
population such that the portion of welds to be inspected in the
remaining portion of the interval be based on the portion of the
interval remaining as of January 1, 2009. Instead, the wording is being
incorrectly interpreted by some licensees as requiring all the welds to
be distributed over, and inspected during, the remaining periods and
outages in the interval. The NRC proposes to revise footnote 1 to Sec.
50.55a(g)(6)(ii)(E) to clarify this issue.
10 CFR 50.55a(g)(6)(ii)(F) Examination Requirements for Class 1 Piping
and Nozzle Dissimilar-Metal Butt Welds (New)
The NRC proposes to add a new Sec. 50.55a(g)(6)(ii)(F) to require
licensees to implement ASME Code Case N-770, ``Alternative Examination
Requirements and Acceptance Standards for Class 1 PWR Piping and Vessel
Nozzle Butt Welds Fabricated with UNS N06082 or UNS W86182 Weld Filler
Material With or Without the Application of Listed Mitigation
Activities, Section XI, Division 1,'' with 15 conditions. Code Case N-
770 contains baseline and ISI requirements for unmitigated butt welds
fabricated with Alloy 82/182 material and preservice and ISI
requirements for mitigated butt welds.
The application of ASME Code Case N-770 is necessary because the
inspections currently required by the ASME Code, Section XI, were not
written to address degradation of Alloy 82/182 butt welds by primary
water stress corrosion cracking (PWSCC), and the safety consequences of
inadequate inspections can be significant. NRC's determination that
current inspections of certain Class 1 butt welds are inadequate is
based upon operating experience and analysis. The absence of an
effective inspection regime could, over time, result in unacceptable
circumferential cracking or the degradation of reactor coolant system
components by corrosion from leaks in these welds. These degradation
mechanisms increase the probability of a loss of coolant accident. The
current ASME Code requirements for inspection of Alloy 82/182 butt
welds are not frequent enough to ensure that ASME Code-allowable limits
will continue to be met in the event that PWSCC initiates. The growth
rate of PWSCC in these welds is rapid enough that PWSCC could lead to
leakage or rupture before the degradation would be detected by the
inspections in the ASME Code, Section XI, currently required by 10 CFR
50.55a or by the 2005 Addenda through the 2008 Addenda of Section XI.
In late 2005, the NRC sent a letter to ASME requesting it to
address the inspection requirements for Class 1 PWR piping butt welds
fabricated with Alloy 82/182 weld materials. ASME approved the
development of an ASME code case on appropriate inspection frequency
requirements for Class 1 butt welds containing Alloy 82/182 to address
primary water stress-corrosion cracking (PWSCC). The code case format
was chosen by ASME to address this safety-significant issue because a
code case is a stand-alone set of provisions that can be approved more
quickly than revisions to the ASME B&PV Code. Code cases are voluntary,
however, so these provisions were developed with the expectation that
the NRC would incorporate the code case by reference into the
regulations. ASME Code Case N-770, was approved by ASME on January 30,
2009, and was published in Supplement 8 of the 2007 Edition of the ASME
Boiler and Pressure Vessel Code Nuclear Code Cases book. ASME Code Case
N-770 provides inspection frequencies and methods for Alloy 82/182 butt
welds that are unmitigated as well as butt welds that have been
mitigated for PWSCC by any of several mitigation methods. ASME Code
Case N-770, with proposed conditions, resolves the deficiencies in the
ASME B&PV Code, Section XI, inspection requirements for Alloy 82/182
butt welds by providing inspection requirements that ensure that ASME
Code-allowable limits will not be exceeded and PWSCC will not lead to
leaks or ruptures of piping welds. Therefore, the NRC proposes to
require the implementation of Code Case N-770, with conditions.
The NRC proposes to add a condition (Sec. 50.55a(g)(6)(ii)(F)(2))
to require that welds mitigated by inlays, cladding, or stress
improvement by welding, be categorized as unmitigated welds pending
plant-specific NRC review of the mitigation techniques and NRC
authorization of an alternative ASME Code Case N-770 Inspection Item
for the mitigated weld. ASME Code Case N-770 provides inspection
methods and frequencies for welds mitigated by certain specified
techniques. Inspections of mitigated welds are performed much less
frequently than unmitigated welds. Requirements for most of the
mitigation methods are contained in other ASME code cases under
development. The NRC has typically approved the application of pressure
boundary weld mitigation techniques on a case-by-case basis. This
condition is necessary to ensure that appropriate mitigation techniques
are
[[Page 24343]]
applied to welds before they are categorized as mitigated under Code
Case N-770.
The NRC proposes to add a condition (Sec. 50.55a(g)(6)(ii)(F)(3))
to require that the baseline examination of welds in Inspection Items
A-1, A-2, and B (unmitigated welds) be completed at the next refueling
outage after the effective date of the final rule. Paragraph -2200 of
Code Case N-770 permits welds in Inspection Items A-1, A-2, and B
(unmitigated welds) that have not received a baseline examination to be
examined within the next two refueling outages from adoption of the
Code Case. Welds in Inspection Items A-1, A-2, and B are the welds most
likely to experience PWSCC and some of these welds may not have
received a baseline examination, even under the industry initiative,
MRP-139. This condition is necessary to ensure the integrity of these
welds by requiring that all welds in Inspection Items A-1, A-2 and B be
inspected at the first opportunity to perform the inspections.
The NRC proposes to add a condition (Sec. 50.55a(g)(6)(ii)(F)(4))
to require essentially 100 percent coverage for axial flaws. Paragraph
-2500(c) of Code Case N-770 permits examination of axial flaws with
inspection coverage limitations provided essentially 100 percent
coverage for circumferential flaws is achieved and the maximum coverage
practical is achieved for axial flaws. This requirement on inspection
limitations is inconsistent with comparable inspection requirements of
the ASME B&PV Code, Section XI. Axial flaws can lead to through wall
cracks and leakage of reactor coolant, which is a safety concern. This
condition is necessary for the NRC to ensure that, through NRC review
of an authorization of alternative inspection coverage, appropriate
actions are being taken to address potential inspection limitations for
axial flaws.
The NRC proposes to add a condition (Sec. 50.55a(g)(6)(ii)(F)(5))
to reword Paragraph -3132.3(b) on determining flaw growth using wording
consistent with that used in the ASME B&PV Code, Section XI. Paragraph
-3132.3(b) contains the statement that a ``flaw is not considered to
have grown if the size difference (from a previous examination) is
within the measurement accuracy of the nondestructive examination (NDE)
technique employed.'' The ``measurement accuracy of the NDE technique
employed'' is not defined in the code case or in the ASME B&PV Code.
Use of this terminology may result in a departure from the past
practice when applying ASME B&PV Code, Section XI. Under the
requirements of Section XI, one concludes that flaw growth has not
occurred when a ``previously evaluated flaw has remained essentially
unchanged.'' The proposed condition uses this wording. This condition
is necessary to clarify the requirements for determining whether flaw
growth has occurred and make the requirements consistent with ASME B&PV
Code requirements endorsed by the NRC in 10 CFR 50.55a.
The NRC proposes to add a condition (Sec. 50.55a(g)(6)(ii)(F)(6))
on welds that are determined through a volumetric examination to have
cracking that penetrates beyond the thickness of the inlay or cladding.
The condition would require such welds to be reclassified as Inspection
Item A-1, A-2, or B, as appropriate, until corrected by repair/
replacement activity in accordance with IWA-4000 or by corrective
measures beyond the scope of Code Case N-770. Code Case N-770 would
permit welds mitigated by inlay or cladding (i.e., onlay) in Inspection
Items G, H, J, and K, to remain in those Inspection Items if cracking
that penetrates through the thickness of the inlay or cladding occurs.
The purpose of an inlay or cladding is to provide a corrosion resistant
barrier between reactor coolant and the underlying Alloy 82/182 weld
material that is susceptible to PWSCC. If cracking penetrates through
the thickness of an inlay or cladding, the inspection frequencies of
Inspection Items G, H, J, and K would no longer be appropriate even
after satisfying the successive examination requirements of paragraph -
2420. This condition is necessary because welds with cracking that
penetrates beyond the thickness of the protective barrier of the inlay
or cladding would no longer be mitigated and would need to be inspected
under one of the Inspection Items for unmitigated welds.
The NRC proposes to add a condition (Sec. 50.55a(g)(6)(ii)(F)(7))
on welds in Inspection Items G, H, J, and K, (welds mitigated by inlay
or cladding) that the ISI surface examination requirements of Table 1
should apply whether the inservice volumetric examinations are
performed from the weld outside diameter or the weld inside diameter.
Code Case N-770 only requires a surface examination for welds in
Inspection Items G, H, J, and K if a volumetric examination is
performed from the weld inside diameter surface. A volumetric
examination performed from the weld outside diameter surface would not
be capable of detecting flaws in an inlay or cladding. This condition
is necessary to ensure that weld inlays or cladding are still
performing their intended function of providing a protective barrier
between the reactor coolant and the underlying Alloy 82/182 weld that
is susceptible to PWSCC.
The NRC also proposes, as part of a new condition as Sec.
50.55a(g)(6)(ii)(F)(7), to require that all hot-leg operating
temperature welds in Inspection Items G, H, J, and K (welds mitigated
by inlay or cladding) be inspected each interval and that a 25 percent
sample of cold leg operating temperature welds in Inspection Items G,
H, J, and K be inspected whenever the core barrel is removed (unless it
has already been inspected within the past 10 years) or 20 years,
whichever is less. Code Case N-770 permits welds in Inspection Items G,
H, J, and K to be placed in a 25 percent sample inspection program
under certain conditions after the required initial inspection. The NRC
has performed analyses of crack growth in welds mitigated by Alloy 52/
152 inlay or cladding using experimentally derived crack growth data
for this weld material. The results of those analyses show that welds
in Inspection Items G, H, J, and K at hot leg temperature have to be
examined once per interval and welds at cold leg temperature have to be
inspected under a sample inspection program to detect potentially
significant crack growth. This condition is being proposed to ensure
that ASME Code-allowable limits would not be exceeded and PWSCC would
not lead to leaks or ruptures.
The NRC proposes to add a condition (Sec. 50.55a(g)(6)(ii)(F)(8))
to prohibit the first examination following weld inlay, cladding, or
stress improvement for Inspection Items D, G, and H from being deferred
to the end of the interval. Code Case N-770 provides requirements on
the timing of the first examination following weld inlay, cladding, or
stress improvement. Inspection Items D, G, and H pertain to mitigation
of cracked welds and the timing of the initial examinations in the code
case has been specified in the code case so that the welds are not in
service for an extended time period prior to the initial examination.
However, the code case does not explicitly preclude deferral of these
examinations to the end of the interval. Therefore, this NRC condition
is needed to ensure that the initial examinations of welds in
Inspection Items D, G, and H take place on an appropriate schedule to
verify the effectiveness of the mitigation process.
The NRC proposes to add a condition (Sec. 50.55a(g)(6)(ii)(F)(9))
on Measurement or Quantification Criterion I-1.1 of Appendix I to
require the assumption in the weld residual stress (WRS) analysis of a
construction weld repair from the
[[Page 24344]]
inside diameter to a depth of 50 percent of the weld thickness
extending 360[deg] around the weld. Measurement or Quantification
Criterion I-1.1 does not specify the circumferential extent of the
repair that must be assumed. This condition is necessary to clarify the
size of the repair to be assumed in the weld residual stress analysis
which would ensure that appropriate criteria for the WRS analysis are
used for mitigation by stress improvement.
The NRC proposes to add a condition (Sec. 50.55a(g)(6)(ii)(F)(10))
on Measurement or Quantification Criterion I-2.1 of Appendix I to
require that the last sentence be replaced. This criterion was
inappropriately worded since this criterion pertains to the permanence
of a mitigation process by stress improvement and plastic ``shakedown''
rather than ``ratcheting'' is the phenomenon that could lead to stress
relaxation. This condition is necessary to clarify the type of analysis
necessary to ensure that the mitigation process is permanent and that
the inspection frequencies associated with the process continue to be
correct.
The NRC proposes to add a condition (Sec. 50.55a(g)(6)(ii)(F)(11))
to require that in applying Measurement or Quantification Criterion I-
7.1 of Appendix I, an analysis be performed using IWB-3600 evaluation
methods and acceptance criteria to verify that the mitigation process
will not cause any existing flaws to grow. Measurement or
Quantification Criterion I-7.1 permits the growth of existing flaws in
welds mitigated by stress improvement. This is an inappropriate
provision since the process of mitigating by stress improvement is
intended to prevent growth of existing flaws which could lead to
leakage or rupture of the weld. This condition is necessary to ensure
that stress improvement of welds with existing flaws is an effective
mitigation technique consistent with the inspection frequency in the
code case.
The NRC proposes to add a condition (Sec. 50.55a(g)(6)(ii)(F)(12))
to require that the NRC be provided with a report if the volumetric
examination of any mitigated weld detects new flaws or growth of
existing flaws that exceed the acceptance standards of IWB-3514 and are
found to be acceptable for continued service through an analytical
evaluation or a repair or the alternative requirements of an ASME code
case. The report would summarize the evaluation, along with inputs,
methodologies, assumptions, and cause of the new flaw or flaw growth
and would be provided to the NRC prior to the weld being placed in
service. Welds that are mitigated have been modified by a technique,
such as weld inlays, cladding, or stress improvement. Mitigation
techniques are designed to prevent new flaws from occurring and prevent
the growth of any existing flaws. If volumetric examination detects new
flaws or growth of existing flaws in the required examination volume,
the mitigation will not be performing as designed and the NRC will need
to evaluate the licensee's actions to address the problem. Therefore,
this condition is needed to verify the acceptability of the weld prior
to being placed back in service.
The NRC proposes to add a condition (Sec. 50.55a(g)(6)(ii)(F)(13))
to require that the last sentence of the Extent and Frequency of
Examination for Inspection Items C and F be revised. Inspection Items C
and F apply to butt welds mitigated by full structural weld overlays of
Alloy 52/152 material. Note 10 of the Code Case requires that welds in
Inspection Items C and F that are not included in the 25 percent sample
be examined prior to the end of the mitigation evaluation period if the
plant is to be operated beyond that time. This condition would ensure
that welds in the 25 percent sample are also examined prior to the end
of the mitigation evaluation period; that is, prior to the end of life
of the overlay predicted by the mitigation evaluation. Inspection prior
to the end of the mitigation evaluation period is necessary to ensure
that appropriate information has been obtained to verify the condition
of the weld overlay and update the analysis for the predicted life of
the weld overlay.
The NRC proposes to add a condition (Sec. 50.55a(g)(6)(ii)(F)(14))
on the \1/2\-inch (13 mm) dimension shown in Figures 2(b) and 5(b) of
Code Case N-770. The condition would require that a dimension ``b'' be
used instead of [frac12] inch, where ``b'' is equivalent to the nominal
thickness of the nozzle or pipe being overlaid, as appropriate. The
code case contains information on component thicknesses to be used in
application of the acceptance standards of ASME B&PV Code, Section XI,
IWB-3514, to evaluate flaws detected during preservice inspection of
weld overlays. The \1/2\-inch (13 mm) dimension shown in Figures 2(b)
and 5(b) is non-conservative. The appropriate dimension is a function
of the nominal thickness of the nozzle or pipe being overlaid and not a
single specified value for all pipes and nozzles. This condition is
necessary to ensure that acceptance standards used for evaluation of
any flaws detected during preservice inspection of weld overlays assure
an appropriate level of safety.
The NRC proposes to add a condition (Sec. 50.55a(g)(6)(ii)(F)(15))
on the use of the acceptance standards of ASME B&PV Code, Section XI,
IWB-3514, for evaluating indications in inlays or onlays. The proposed
condition specifies that the thickness ``t'' in IWB-3514 is the
thickness of the inlay or onlay. The code case requires that the
preservice examination for inlays or onlays consist of a surface
examination, which does not allow planar flaws, and a volumetric
examination. The volumetric examination allows the use of the
acceptance standards of IWB-3514 provided the surface examination
acceptance standards are satisfied. That is, it would allow the
acceptance of some subsurface indications, but IWB-3514 acceptance
standards would only allow very small flaws. However, the code case
does not specify the value ``t'' to be used in the application of IWB-
3514. The appropriate value ``t'' when applying IWB-3514 to inlays or
onlays is the thickness of the inlay or onlay, since the acceptance
standards in this case only apply to accepting flaws within the inlay
or onlay. This condition is necessary to preclude the misapplication of
the acceptance standards of IWB-3514 and potential acceptance of flaws
that could compromise the integrity and function of the inlay or onlay
as a protective barrier.
The NRC proposes to add a condition (Sec. 50.55a(g)(6)(ii)(F)(16))
on welds mitigated by stress improvement by welding in Inspection Items
D and E to not permit them to be placed into a population to be
examined on a sample basis after the initial examination. Stress
improvement by welding is also called an optimized weld overlay. Code
Case N-770 permits welds mitigated by this technique to be placed in a
25 percent inspection sample after the initial examination. Sample
inspections could result in three-quarters of the welds never being
examined after the initial examination. Although full structural weld
overlays have been used extensively in the nuclear industry for many
years, the industry does not have experience with optimized weld
overlays. Optimized weld overlays are designed to rely on the outer 25
percent of the original Alloy 82/182 material to satisfy the design
margins and would not satisfy design margins if significant cracking
were to occur. If significant cracking were to occur in the Alloy 82/
182 material, the optimized weld overlay material would prevent the
weld from leaking and could potentially rupture without prior evidence
of leakage under design basis conditions.
[[Page 24345]]
The proposed condition is necessary to ensure that all optimized weld
overlays are periodically inspected for potential degradation.
After ASME Code Case N-770 was approved by ASME in early 2009, the
NRC brought concerns on the code case to the attention of members of
the ASME B&PV Code, Section XI, task group that developed it. These
concerns are the subject of these proposed conditions. The ASME B&PV
Code, Section XI, has been working on a revision to Code Case N-770 to
address many of these concerns. The NRC will consider endorsing an
ASME-approved revision to Code Case N-770 in the final rule to update
10 CFR 50.55a, depending upon when such a revision is issued and the
contents of the revision, and may remove some or all conditions
depending upon whether the revised Code Case addresses the concerns
previously discussed.
Substitution of the Term ``Condition'' in 10 CFR 50.55a
The NRC proposes to substitute the word ``condition(s)'' for the
words ``limitation(s)'' ``modification(s)'' and ``provision(s),''
throughout 10 CFR 50.55a as shown in Table 1 of this document for
consistency. The NRC does not believe it necessary to distinguish among
different types of ``caveats'' that it imposes on the use of the ASME
Codes, and therefore proposes to use a single term for clarity and
consistency.
IV. Paragraph-by-Paragraph Discussion
Quality Standards, ASME Codes and IEEE Standards, and Alternatives
10 CFR 50.55a(a)
The NRC proposes to add the title ``Quality standards, ASME Codes
and IEEE standards, and alternatives'' to paragraph (a).
Applicant/Licensee Proposed Alternatives to the Requirements of 10 CFR
50.55a
10 CFR 50.55a(a)(3)
The NRC proposes to add a sentence to paragraph (a)(3) to clarify
that an alternative is to be submitted to, and approved by, the NRC
prior to an applicant or licensee implementing the alternative. For
applicants, approval of an alternative must be obtained before
construction begins (rather than during the design process).
Standards Approved for Incorporation by Reference
10 CFR 50.55a(b)
The NRC proposes to add the title ``Standards approved for
incorporation by reference'' to paragraph (b).
The NRC proposes to modify the language in paragraph (b) to clarify
that non-mandatory appendices are excluded from the ASME B&PV Code,
Section III requirements that are incorporated by reference into 10 CFR
50.55a, and to clarify that only Division 1 requirements of Section III
and Section XI are incorporated by reference (not Division 2 and
Division 3 requirements).
ASME B&PV Code, Section III
10 CFR 50.55a(b)(1)
The NRC proposes to amend paragraph (b)(1) to incorporate by
reference the 2005 Addenda (Division 1) through 2008 Addenda (Division
1) of Section III of the ASME B&PV Code into 10 CFR 50.55a, subject to
the conditions outlined in modified paragraphs (b)(1)(i) through
50.55a(b)(1)(vi) and proposed paragraph (b)(vii). The paragraph
modification would also include an editorial change to the references
to Section III ASME B&PV Code for clarification purposes. As a result,
applicants and licensees may use the 1974 Edition (Division 1) through
the 2008 Addenda (Division 1) of Section III of the ASME B&PV Code
subject to the conditions contained within modified paragraphs
(b)(1)(i) through (b)(1)(vi) and new paragraph (b)(1)(vii).
10 CFR 50.55a(b)(1)(ii)
The NRC proposes to apply the existing condition in paragraph
(b)(1)(ii) regarding stress indices used for weld stresses in piping
design to the comparable provisions in the ASME Code editions and
addenda incorporated by reference in this proposed rule. The paragraph
modification also includes the addition of a condition on the use of
paragraph NB-3683.4(c)(2) for applicants and licensees applying the
1989 Addenda through the latest edition and addenda of Section III of
the ASME B&PV Code. As a result, this modification prohibits the use of
Footnote 13 from the 2004 Edition through the 2008 Addenda of Section
III of the ASME B&PV Code to Figures NC-3673.2(b)-1 and ND-3673.2(b)-1
for welds with leg size less than 1.09 times the nominal pipe wall
thickness (tn) for applicants and licensees applying the
1989 Addenda through the latest edition and addenda of Section III of
the ASME B&PV Code. Also as a result, the use of paragraph NB-
3683.4(c)(2), is not allowed for applicants and licensees applying the
1989 Addenda through the latest edition and addenda of Section III of
the ASME B&PV Code.
10 CFR 50.55a(b)(1)(iii)
The NRC proposes to modify paragraph (b)(1)(iii) to impose
conditions on the seismic design of piping when licensees use the
latest editions and addenda of the ASME B&PV Code, Section III,
incorporated by reference in modified paragraph (b). The paragraph
would also be modified with an editorial change to replace
``limitations and modifications'' with ``conditions'' and
``limitation'' with ``condition.'' The modified paragraph would allow
the use of Subarticles NB-3200, NB-3600, NC-3600, and ND-3600 for the
seismic design of piping when applying editions and addenda, up to and
including the 1993 Addenda of the ASME B&PV Code, Section III, subject
to the condition in modified paragraph (b)(1)(ii). The modified
paragraph would not allow the use of Subarticles NB-3200, NB-3600, NC-
3600, and ND-3600 for the seismic design of piping when applying the
1994 Addenda through the 2006 Addenda of Section III of the ASME B&PV
Code except that Subarticle NB-3200 in the 2004 Edition through the
2008 Addenda of Section III of the ASME B&PV Code may be used by
applicants and licensees subject to the condition in new paragraph
(b)(1)(iii)(B). The modified paragraph would allow the use of
Subarticles NB-3200, NB-3600, NC-3600, and ND-3600 for the seismic
design of piping when applying the 2006 Addenda through the 2008
Addenda of Section III of the ASME B&PV Code, subject to the three new
conditions in new paragraphs (b)(1)(iii)(A), (b)(1)(iii)(B), and
(b)(1)(iii)(C).
10 CFR 50.55a(b)(1)(iii)(A)
NRC proposes to add a new paragraph (b)(1)(iii)(A) to impose a
condition on the minimum value of the B2 indices when
applicants and licensees use Subarticle NB-3600 of the 2006 Addenda up
to and including the 2008 Addenda of the ASME Code, Section III, for
the seismic design of piping. As a result, licensees and applicants
using Subarticle NB-3600 of the 2006 Addenda up to and including the
2008 Addenda of the ASME B&PV Code, Section III, for the seismic design
of piping must use a value for the B2 index, defined in
Subparagraph NB-3656(b)(3), equal to or greater than 0.75B2,
from Table NB-3681(A)-1, for Class 1 elbows and tees of ferritic steel
[[Page 24346]]
materials operating at temperatures above 300[deg]F.
10 CFR 50.55a(b)(1)(iii)(B)
The NRC proposes to add a new paragraph (b)(1)(iii)(B) requiring
licensees and applicants using Note (1) of Figure NB-3222-1 in Section
III of the 2004 Edition up to and including the 2008 Addenda of the
ASME B&PV Code to include reversing dynamic loads in calculating
primary bending stresses, if consideration of these loads is warranted.
10 CFR 50.55a(b)(1)(iii)(C)
The NRC proposes to add a new paragraph(b)(1)(iii)(C) to impose a
condition on the use of Subarticles NB-3600, NC-3600, and ND-3600 of
the ASME B&PV Code, Section III when applying the 2006 Addenda through
the 2008 Addenda of Section III of the ASME B&PV Code by requiring the
outer diameter-over-thickness ratio (Do/t) to be less than
or equal to 40. As a result, licensees and applicants may not apply
Subparagraph NB-3683.2(C), Note (1) to Table NB-3681(a)-1, and Note (3)
to Figures NC-3673.2(b)-1 and ND-3673.2(b)-1.
10 CFR 50.55a(b)(1)(iv)
The NRC proposes to modify paragraph (b)(1)(iv) to allow the use
the 1994 Edition of NQA-1 when applying the 2006 Addenda and later
Editions and Addenda of the ASME B&PV Code, Section III.
10 CFR 50.55a(b)(1)(vii)
The NRC proposes to add a new paragraph (b)(1)(vii) to prohibit the
use of paragraph NB-7742 when applying the 2006 Addenda up to and
including the 2007 Edition and 2008 Addenda of the ASME B&PV Code,
Section III. As a result, new Class 1 incompressible-fluid, pressure-
relief valve designs must be tested at the highest values of set-
pressure ranges as required by prior editions and addenda of the ASME
B&PV Code, Section III.
ASME B&PV Code, Section XI
10 CFR 50.55a(b)(2)
The NRC proposes to revise the introductory text to paragraph
(b)(2) to incorporate by reference only Subsections IWA, IWB, IWC, IWD,
IWE, IWF, IWL, Mandatory and Non-Mandatory Appendices, of the 2005
Addenda through 2008 Addenda of Section XI of the ASME B&PV Code, with
conditions, into 10 CFR 50.55a. It would also be revised to make an
editorial change to the reference to Section XI of the ASME B&PV Code.
10 CFR 50.55a(b)(2)(i)
The NRC proposes to delete the requirements of current paragraph
(b)(2)(i) which address limitations on specific editions and addenda.
Licensees are no longer using these older editions (1974 and 1977
Editions) and addenda of the ASME B&PV Code. The requirements of
current paragraph (b)(2)(ii) which address pressure-retaining welds in
ASME Code Class 1 piping would be redesignated as paragraph (b)(2)(i),
with no change to redesignated language.
10 CFR 50.55a(b)(2)(ii)
The NRC proposes to redesignate the requirements of current
paragraph (b)(2)(vi), which address containment inservice inspection
requirements, as paragraph (b)(2)(ii). This paragraph is also modified
to clarify the conditions applicable to this paragraph.
10 CFR 50.55a(b)(2)(iii)
The NRC proposes to delete the requirements of current paragraph
(b)(2)(iii) which address steam generator tubing. The NRC proposes
removal of this condition because the condition is redundant to the
1989 Edition through the 2008 Addenda of Section XI. The requirements
of current paragraph (b)(2)(vii) which address Section XI references to
OM Part 4, OM Part 6, and OM Part 10 would be redesignated as paragraph
(b)(2)(iii), with no change to redesignated language.
10 CFR 50.55a(b)(2)(iv)
The NRC proposes to redesignate the requirements of current
paragraph (b)(2)(viii), which address the inservice examination of
concrete containments in accordance with Subsection IWL of the ASME
B&PV Code, Section XI, as paragraph (b)(2)(iv). This paragraph is also
modified so that the conditions in redesignated paragraphs
(b)(2)(iv)(F) and (b)(2)(iv)(G) do not apply when using the 2007
Edition with 2008 Addenda of the ASME B&PV Code, Section XI.
10 CFR 50.55a(b)(2)(v)
The NRC proposes to redesignate the requirements of current
paragraph (b)(2)(ix), which address the examination of metal
containments and the liners of concrete containments in accordance with
Subsection IWE of the ASME B&PV Code, Section XI, as paragraph
(b)(2)(v). This paragraph is also modified so that the conditions in
redesignated paragraphs (b)(2)(v)(F), (b)(2)(v)(G), (b)(2)(v)(H) and
(b)(2)(v)(I) do not apply when using the 2004 Edition with 2006 Addenda
through the 2007 Edition with 2008 Addenda of Subsection IWE of the
ASME B&PV Code, Section XI. Also, this paragraph is modified so that
the condition in redesignated paragraph (b)(2)(v)(I) would not apply
when using the 2004 Edition, up to and including, the 2005 Addenda of
Subsection IWE of the ASME B&PV Code, Section XI.
10 CFR 50.55a(b)(2)(v)(J)
The NRC proposes to add a new paragraph (b)(2)(v)(J) to address
major containment modifications as they apply to Class MC and Class CC
containment structures and the use of Article IWE-5000, of Subsection
IWE when applying the 2007 Edition up to and including the 2008 Addenda
of the ASME B&PV Code, Section XI.
10 CFR 50.55a(b)(2)(vi)
The NRC proposes to redesignate the requirements in current
paragraph (b)(2)(x), which address Quality Assurance, as paragraph
(b)(2)(vi), with no change to the redesignated language.
10 CFR 50.55a(b)(2)(vii)
The NRC proposes to redesignate the current paragraph (b)(2)(xi),
which is ``Reserved,'' as paragraph (b)(2)(vii), and that it remain
reserved for possible future use.
10 CFR 50.55a(b)(2)(viii)
The NRC proposes to redesignate the requirements in current
paragraph (b)(2)(xii), which address underwater welding, as paragraph
(b)(2)(viii), with no change to the redesignated language.
10 CFR 50.55a(b)(2)(ix)
The NRC proposes to redesignate the current paragraph (b)(2)(xiii),
which is ``Reserved,'' as paragraph (b)(2)(ix), and that it remain
reserved for possible future use.
10 CFR 50.55a(b)(2)(x)
The NRC proposes to redesignate the requirements in current
paragraph (b)(2)(xiv), which address Appendix VIII personnel
qualifications, as paragraph (b)(2)(x), with no change to the
redesignated language.
10 CFR 50.55a(b)(2)(xi)
The NRC proposes to redesignate the requirements in current
paragraph (b)(2)(xv), which address Appendix VIII specimen set and
qualification requirements, as paragraph (b)(2)(xi). The paragraph
would be modified by limiting the use of the provisions described in
redesignated paragraphs (b)(2)(xi)(A) through (b)(2)(xi)(M) to
licensees using editions and addenda of the B&PV Code after the 2001
Edition through the 2006 Addenda.
[[Page 24347]]
10 CFR 50.55a(b)(2)(xii)
The NRC proposes to redesignate the requirements in current
paragraph (b)(2)(xvi), which address Appendix VIII single-sided
ferritic-vessel and piping and stainless steel piping examination, as
paragraph (b)(2)(xii), with no change to the redesignated language.
10 CFR 50.55a(b)(2)(xiii)
The NRC proposes to redesignate the requirements in current
paragraph (b)(2)(xvii), which address reconciliation of quality
requirements, as paragraph (b)(2)(xiii), with no change to the
redesignated language.
10 CFR 50.55a(b)(2)(xiv)(A)
The NRC proposes to redesignate the requirements in current
paragraph (b)(2)(xviii)(A), which address certification of NDE
personnel, as paragraph (b)(2)(xiv)(A), with no change to the
redesignated language.
10 CFR 50.55a(b)(2)(xiv)(B)
The NRC proposes to redesignate the requirements in current
paragraph (b)(2)(xviii)(B), which address Certification of NDE
personnel, as paragraph (b)(2)(xiv)(B). In addition, the requirements
would be revised such that the condition would not apply to the 2007
Edition through the 2008 Addenda of Section XI.
10 CFR 50.55a(b)(2)(xiv)(C)
The NRC proposes to redesignate the requirements in current
paragraph (b)(2)(xviii)(C), which address certification of NDE
personnel, as paragraph (b)(2)(xiv)(C). In addition, the requirements
would be revised such that the current conditions on the qualification
of VT-3 examination personnel would not apply to the 2005 Addenda
through the 2008 Addenda of Section XI.
10 CFR 50.55a(b)(2)(xv)
The NRC proposes to redesignate the requirements in current
paragraph (b)(2)(xix), which address substitution of alternative
methods, as paragraph (b)(2)(xv). In addition, the requirements would
be revised so the current conditions for the substitution of
alternative examination methods in that paragraph would not apply when
using the 2005 Addenda through the 2008 Addenda. The paragraph would
also be revised to impose the condition that paragraphs IWA-4520(b)(2)
and IWA-4521 of the 2007 Edition of Section XI, Division 1, with 2008
Addenda, are not approved for use.
10 CFR 50.55a(b)(2)(xvi)
The NRC proposes to redesignate the requirements in current
paragraph (b)(2)(xx), which address system leakage tests, as paragraph
(b)(2)(xvi), with no change to the redesignated language.
10 CFR 50.55a(b)(2)(xvii)
The NRC proposes to redesignate the requirements in current
paragraph (b)(2)(xxi), which address Table IWB-2500-1 examination
requirements, as paragraph (b)(2)(xvii), with no change to the
redesignated language.
10 CFR 50.55a(b)(2)(xviii)
The NRC proposes to redesignate the requirements in current
paragraph (b)(2)(xxii), which address surface examination, as paragraph
(b)(2)(xviii), with no change to the redesignated language.
10 CFR 50.55a(b)(2)(xix)
The NRC proposes to redesignate the requirements in current
paragraph (b)(2)(xxiii), which address evaluation of thermally cut
surfaces, as paragraph (b)(2)(xix), with no change to the redesignated
language.
10 CFR 50.55a(b)(2)(xx)
The NRC proposes to redesignate the requirements in current
paragraph (b)(2)(xxiv), which address incorporation of the performance
demonstration initiative and addition of ultrasonic examination
criteria, as paragraph (b)(2)(xx). In addition, the requirements would
be revised so that the current condition would not apply when using the
2007 Edition through the 2008 Addenda of Section XI of the ASME B&PV
Code.
10 CFR 50.55a(b)(2)(xxi)
The NRC proposes to redesignate the requirements in current
paragraph (b)(2)(xxv), which address mitigation of defects by
modification, as paragraph (b)(2)(xxi), with no change to the
redesignated language.
10 CFR 50.55a(b)(2)(xxii)
The NRC proposes to redesignate the requirements in current
paragraph (b)(2)(xxvi), which address pressure testing of Class 1, 2,
and 3 mechanical joints, as paragraph (b)(2)(xxii), with no change to
the redesignated language.
10 CFR 50.55a(b)(2)(xxiii)
The NRC proposes to redesignate the requirements in current
paragraph (b)(2)(xxvii), which address removal of insulation, as
paragraph (b)(2)(xxiii). In addition, the requirements would be revised
to add a condition to refer to paragraph IWA-5241 instead of IWA-5242
for the 2007 Edition and later addenda of Section XI of the ASME B&PV
Code.
10 CFR 50.55a(b)(2)(xxiv)
The NRC proposes to add a new paragraph (b)(2)(xxiv) which would
condition the use of the fatigue crack growth rate calculation for
subsurface flaws defined in paragraph A-4300(b)(1) of Section XI,
Nonmandatory Appendix A when the ratio of the minimum cyclic stress to
the maximum cyclic stress (R) is less than zero.
10 CFR 50.55a(b)(2)(xxv)
The NRC proposes to add a new paragraph (b)(2)(xxv) which would
condition the use of ASME B&PV Code, Section XI, Non-Mandatory Appendix
E, by establishing that Section E-1200 is not acceptable for use.
10 CFR 50.55a(b)(2)(xxvi)
The NRC proposes to add a new paragraph (b)(2)(xxvi) which would
condition the use of ASME B&PV Code, Section XI, Non-Mandatory Appendix
R to require licensees to submit an alternative in accordance with
paragraph (a)(3) and obtain NRC authorization of the proposed
alternative prior to implementing Appendix R, RI-ISI programs.
ASME OM Code
10 CFR 50.55a(b)(3)
The NRC proposes to revise the introductory text of paragraph
(b)(3) to require that the 2004 Edition with the 2005 and 2006 Addenda
of the ASME OM Code be used during the initial 120-month IST interval
under paragraph (f)(4)(i) and during mandatory 120-month IST program
updates under paragraph (f)(4)(ii). The proposed revision would also
allow users to voluntarily update their IST programs to the 2004
Edition with the 2005 and 2006 Addenda of the ASME OM Code under
paragraph (f)(4)(iv).
10 CFR 50.55a(b)(3)(v)
The NRC proposes to revise paragraph (b)(3)(v) to require that the
provisions in Subsection ISTD of the ASME OM Code be used for the
inservice examination and testing of snubbers when using the 2006
Addenda and later editions and addenda of Section XI.
10 CFR 50.55a(b)(3)(vi)
The NRC proposes to revise paragraph (b)(3)(vi) to require that the
current condition for exercising manual valves continue to apply when
using the 1999 through 2005 Addenda of the ASME OM Code. This condition
would not apply to the 2006 Addenda and later
[[Page 24348]]
editions and addenda of the ASME OM Code.
Reactor Coolant Pressure Boundary, Quality Group B Components and
Quality Group C Components
The NRC proposes to revise paragraphs (c)(3), (d)(2), and (e)(2) to
replace ``but--'' with ``subject to the following conditions'' at the
end of the introductory text to the paragraphs for clarity.
Inservice Testing Requirements
10 CFR 50.55a(f)(5)(iv)
The NRC proposes to revise paragraph (f)(5)(iv) to clarify that
licensees are required to submit requests for relief based on
impracticality within 12 months after the expiration of the IST
interval for which relief is being sought.
Inservice Inspection Requirements
10 CFR 50.55a(g)(2), (g)(3)(i), (g)(3)(ii), the Introductory Text of
(g)(4), (g)(4)(i), and (g)(4)(ii)
The NRC proposes to revise paragraphs (g)(2), (g)(3)(i),
(g)(3)(ii), (g)(4)(i) and (g)(4)(ii) to require that the provisions in
Subsection ISTD of the ASME OM Code, and the optional ASME code cases
listed in Regulatory Guide 1.192, be used for the ISI of snubbers. The
introductory text of paragraph (g)(4) would be revised to require that
licensees use the provisions for examination and testing snubbers in
Subsection ISTD of the ASME OM Code.
10 CFR 50.55a(g)(4)(iii)
The NRC proposes to revise paragraph (g)(4)(iii) to provide the
proper references to Section XI, Table IWB-2500-1, ``Examination
Category B-J,'' Item Numbers B9.20, B9.21 and B9.22.
10 CFR 50.55a(g)(5)(iii)
The NRC proposes to revise paragraph (g)(5)(iii) by adding a
sentence to clarify that a request for relief must be submitted to the
NRC no later than 12 months after the examination has been attempted
during a given ISI interval and the ASME Code requirement determined to
be impractical.
10 CFR 55a(g)(5)(iv)
The NRC proposes to revise paragraph (g)(5)(iv) to clarify that
licensees are required to submit requests for relief based on
impracticality within 12 months after the end of the ISI interval for
which relief is being sought.
10 CFR 50.55a(g)(6)(ii)(E)(1) through (g)(6)(ii)(E)(3)
The NRC proposes to revise paragraphs (g)(6)(ii)(E)(1) through
(g)(6)(ii)(E)(3) to update the requirement to implement Code Case N-
722-1.
10 CFR 50.55a(g)(6)(ii)(F)
The NRC proposes to add a new paragraph (g)(6)(ii)(F), ``Inspection
Requirements for Class 1 Pressurized Water Reactor Piping and Vessel
Nozzle Butt Welds,'' to require licensees to implement ASME Code Case
N-770, with conditions.
Footnote 1 to 10 CFR 50.55a(g)(6)(ii)(E)
The NRC proposes to revise footnote 1 to paragraph (g)(6)(ii)(E) to
clarify that for inspections conducted once per interval, the portion
of welds to be inspected in the remaining portion of the interval be
based on rules already established by the ASME B&PV Code.
Substitution of the Term ``Condition'' in 10 CFR 50.55a
The NRC proposes to substitute the words ``limitation(s),''
``modification(s),'' and ``provision(s)'' with the word
``condition(s)'' throughout 10 CFR 50.55a, as shown in Table 1 of this
document, for consistency.
V. Generic Aging Lessons Learned Report
In September 2005, the NRC issued ``Generic Aging Lessons Learned
(GALL) Report,'' NUREG-1801, Volumes 1 and 2, Revision 1, for
applicants to use in preparing their license renewal applications. The
GALL Report evaluates existing programs and documents the bases for
determining when existing programs, without change or augmentation, are
adequate for aging management compliance in the license renewal rule,
as given in 10 CFR 54.21(a)(3). In Revision 1 of the GALL Report,
editions of the ASME B&PV Code, Section XI, Subsections IWB, IWC, IWD,
IWE, IWF, and IWL from the 1995 Edition through the 2001 Edition,
inclusive of the 2003 Addenda, were evaluated and were found to be
acceptable editions and addenda for complying with the requirements of
10 CFR 54.21(a)(3), unless specifically noted in specific sections of
the GALL Report.
In the GALL Report, Section XI.M1, ``ASME Section XI Inservice
Inspection, Subsections IWB, IWC, and IWD;'' Section XI.S1, ``ASME
Section XI, Subsection IWE;'' Section XI.S2,''ASME Section XI,
Subsection IWL;'' and Section XI.S3, ``ASME Section XI, Subsection
IWF'' describe the evaluation and technical bases for determining the
adequacy of these ASME Code subsections. In addition, many other aging
management programs (AMPs) in the GALL report rely in part, but to a
lesser degree, on the requirements in the ASME B&PV Code, Section XI.
The NRC has evaluated Subsections IWB, IWC, IWD, IWE, IWF, and IWL
of Section XI of the ASME B&PV Code, 2004 Edition with the 2005 Addenda
through the 2007 Edition with the 2008 Addenda as part of the Sec.
50.55a amendment process to determine if the conclusions of the GALL
Report also apply to AMPs that rely upon the ASME B&PV Code editions
and addenda that are proposed to be incorporated by reference into
Sec. 50.55a by this rule. The NRC finds that the 2004 Edition,
inclusive of the 2005 and 2006 Addenda, and the 2007 Edition, inclusive
of the 2008 Addenda of Sections XI of the ASME B&PV Code, Subsections
IWB, IWC, IWD, IWE, IWF, and IWL, as subject to the conditions of this
rule, are acceptable to be adopted as AMPs for license renewal and the
conclusions of the GALL Report remain valid, except where specifically
noted and augmented in the GALL Report. Accordingly, an applicant for
license renewal may use Subsections IWB, IWC, IWD, IWE, IWF, and IWL of
Section XI of the 2004 Edition with the 2005 and 2006 Addenda through
the 2007 Edition with the 2008 Addenda of the ASME B&PV Code, subject
to conditions proposed in this rule, as acceptable alternatives to the
requirements of the 1995 Edition through the 2001 Edition up to and
including the 2003 Addenda of the ASME B&PV Code, Section XI,
referenced in Revision 1 of the GALL Report in its plant-specific
license renewal application. Similarly, a licensee approved for license
renewal that relied on the GALL AMPs may use Subsections IWB, IWC, IWD,
IWE, IWF, and IWL of Section XI of the 2004 Edition with the 2005
Addenda and the 2006 Addenda through the 2007 Edition with the 2008
Addenda of the ASME B&PV Code as acceptable alternatives to the AMPs
described in the Revision 1 of the GALL report. However, a licensee
must assess and follow applicable NRC requirements with regard to
changes to its licensing basis.
The NRC, however, notes that the GALL Report includes Subsection
IWE and IWL AMPs that are evaluated based on the requirements in the
1992 Edition and 2001 Edition through the 2003 Addenda of Section XI of
the ASME B&PV Code. Also, some of the terminology used and some details
in these AMPs are based on the 1992 Edition. Since these AMPs in
Revision 1 of the GALL report have a specific ASME B&PV Code year in
the description of the AMP or in one or more of the ten elements, the
details in the AMP based on a specific ASME
[[Page 24349]]
B&PV Code edition may not be accurate for other editions.
Revision 1 of the GALL report includes AMPs that are based on the
requirements in the 1995 Edition through the 2003 Addenda of Section XI
of the ASME B&PV Code but in which the AMPs may recommend additional
augmentation of the Code requirements in order to achieve aging
management for license renewal. The technical or regulatory aspects of
the AMPs, for which augmentation is recommended, also apply if using
the 2004 Edition inclusive of the 2005 Addenda, or the 2007 Edition,
inclusive of the 2008 Addenda, of Section XI of the ASME B&PV Code to
meet the requirements of 10 CFR 54.21(a)(3). A license renewal
applicant may either augment its AMPs in these areas, as described in
the GALL report, or propose alternatives (exceptions) for the NRC to
review as part of a plant-specific program element justification for
its AMP.
For PWRs, the NRC currently provides license renewal guidance for
augmented inspections of PWR upper reactor vessel heads and their
penetration nozzles in GALL AMP XI.M11, ``Nickel-Alloy Nozzles and
Penetrations'' and Alloy 600 Line items. As part of this AMP, PWR upper
reactor vessel heads and their penetrations are discussed in GALL AMP
XI.M11A, ``Nickel-Alloy Penetration Nozzles Welded to the Upper Reactor
Vessel Closure Heads of Pressurized Water Reactors (PWR Only).'' The
current program elements and aging management recommendations in GALL
AMP XI.M11A are based on the augmented inspection requirements in the
First Revised Order EA-03-009, ``Issuance of First Revised Order (EA-
03-009) Establishing Interim Inspection Requirements for Reactor
Pressure Vessel Heads at Pressurized Water Reactors.'' For licensees
that have been granted a renewed operating license and have committed
to an AMP that is based on both conformance with GALL AMP XI.M11A and
compliance with First Revised Order EA-03-009, the licensees may update
the program elements of their AMP to reflect compliance with the
proposed requirements in 10 CFR 50.55a(g)(6)(ii)(D) and (g)(6)(ii)(E)
without having to identify an exception to GALL AMP XI.M11A. For new or
current license renewal applicants, they may reference conformance with
GALL AMP XI.M11 and compliance with the proposed augmented inspection
requirements in paragraphs 10 CFR 50.55a(g)(6)(ii)(D), (g)(6)(ii)(E)
and (g)(6)(ii)(F) without the need for taking an exception to the
program elements in GALL AMP XI.M11 or GALL AMP XI.M11A.
VI. Specific Request for Comments
The NRC requests public comment on the changes to Code editions and
addenda, and Code Cases N-722-1 and N-770, as part of this proposed
rulemaking. The NRC also requests comments on specific NRC questions
associated with its implementing 10 CFR 50.55a rulemaking process
improvements to make incorporating by reference ASME B&PV Code editions
and addenda into 10 CFR 50.55a more predictable and consistent. The
primary process improvement is to have a 2-year rulemaking cycle
consisting of 1-year to develop an adequate Regulatory Basis and send a
proposed rule to NRC management for approval, and an additional 1-year
from publishing the proposed rulemaking in the Federal Register to
publishing the final rule (this includes the public comment period).
This 2-year rulemaking cycle is to remain consistent, regardless of the
number of code editions or addenda incorporated into 10 CFR 50.55a in
the rulemaking. This should make publishing these rulemakings more
consistent. However, this does not help users of the ASME B&PV Code
predict when the NRC will incorporate new editions and addenda of the
ASME Code into 10 CFR 50.55a as that would depend on when the NRC
begins each 2-year rulemaking cycle.
As previously mentioned, the ASME issues new editions of the ASME
B&PV Code every 3 years, issues addenda to the editions yearly except
in years when a new edition is issued, and periodically publishes new
editions and addenda of the ASME OM Code. However, the NRC understands
that ASME is re-evaluating this process. The NRC could begin its
rulemaking cycle any time (subject to availability of resources and
other constraints) after the ASME publishes its code editions and
addenda. However, the NRC is trying to determine how often it should
publish its ASME B&PV Code rulemakings to suit the largest number of
users. Some users have told the NRC that they prefer to have code
rulemakings published every 2 years, while others have indicated that
they prefer a 3-year interval. Accordingly, the NRC is requesting
comments on the following questions:
1. What should the scope of the ASME B&PV Code edition and addenda
rulemaking be (i.e., how many editions and addenda should be compiled
into a single rulemaking)?
2. What should the frequency of ASME B&PV Code edition and addenda
rulemaking be (i.e., how often should the NRC incorporate by reference
Code editions and addenda into 10 CFR 50.55a)?
3. In what ways should the NRC communicate the scope, schedule for
publishing the rulemakings in the Federal Register, and status of 10
CFR 50.55a rulemakings to external users?
The NRC will review the responses to these questions to help determine
agency positions on the scope, frequency, and methods to communicate 10
CFR 50.55a rulemakings.
VII. Voluntary Consensus Standards
The National Technology Transfer and Advancement Act of 1995,
Public Law 104-113, requires agencies to use technical standards that
are developed or adopted by voluntary consensus standards bodies
instead of government-unique standards, unless the use of such a
standard is inconsistent with applicable law or is otherwise
impractical. Public Law.104-113 requires Federal agencies to use
industry consensus standards to the extent practical; it does not
require Federal agencies to endorse a standard in its entirety. The law
does not prohibit an agency from generally adopting a voluntary
consensus standard while taking exception to specific portions of the
standard if those provisions are deemed to be ``inconsistent with
applicable law or otherwise impractical.'' Furthermore, taking specific
exceptions furthers the Congressional intent of Federal reliance on
voluntary consensus standards because it allows the adoption of
substantial portions of consensus standards without the need to reject
the standards in their entirety because of limited provisions which are
not acceptable to the agency.
The NRC is proposing to amend its regulations to incorporate by
reference more recent editions and addenda of Sections III and XI of
the ASME B&PV Code and ASME OM Code, for construction, in-service
inspection, and in-service testing of nuclear power plant components.
ASME B&PV and OM Codes are national consensus standards developed by
participants with broad and varied interests, in which all interested
parties (including the NRC and licensees of nuclear power plants)
participate. In an SRM dated September 10, 1999, the Commission
indicated its intent that a rulemaking identify all parts of an adopted
voluntary consensus standard that are not adopted and to justify not
adopting such parts. The parts of the ASME B&PV Code and OM Code that
the NRC proposes not to adopt, or to partially adopt, are
[[Page 24350]]
previously identified in Section II and in the draft regulatory and
backfit analysis. The parts of the ASME B&PV Code, OM Code, and Code
Cases N-722-1 and N-770 that the NRC proposes to be conditionally
acceptable, along with the conditions under which they may be applied,
are also identified in Section II and in the draft regulatory and
backfit analysis. If the NRC did not conditionally accept ASME
editions, addenda, and code cases, it would disapprove these 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
Code editions and addenda, and code cases and any conditions proposed
to be placed on them in this proposed rule does not conflict with any
policy on agency use of consensus standards specified in OMB Circular
A-119.
The justification for not adopting parts of, or conditioning, the
ASME B&PV Code, OM Code, and Code Cases N-722-1 and N-770 as set forth
in these statements of consideration and the draft regulatory and
backfit analysis for this proposed rule, satisfy the requirements of
Section 12(d)(3) of Public Law 104-113, Office of Management and Budget
(OMB) Circular A-119, and the Commission's direction in the SRM dated
September 10, 1999. In accordance with the National Technology Transfer
and Advancement Act of 1995 and OMB Circular A-119, the NRC is
requesting public comment regarding whether other national or
international consensus standards could be endorsed as an alternative
to the ASME B&PV Code and the ASME OM Code.
VIII. Finding of No Significant Environmental Impact: Environmental
Assessment
This proposed action is in accordance with the NRC's policy to
incorporate by reference in 10 CFR 50.55a new editions and addenda of
the ASME B&PV and OM Codes to provide updated rules for constructing
and inspecting components and testing pumps, valves, and dynamic
restraints (snubbers) in light-water nuclear power plants. ASME Codes
are national voluntary consensus standards and are required by the
National Technology Transfer and Advancement Act of 1995, Public Law
104-113, to be used by government agencies unless the use of such a
standard is inconsistent with applicable law or otherwise impractical.
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
proposed action and alternatives to the proposed action (42 U.S.C.
4332(C)); NEPA Sec. 102(C)).
The NRC has determined under NEPA, as amended, and the NRC's
regulations in Subpart A of 10 CFR Part 51, that this proposed rule, if
adopted, would not be a major Federal action significantly affecting
the quality of the human environment and, therefore, an environmental
impact statement is not required. The proposed rulemaking will not
significantly increase the probability or consequences of accidents; no
changes are being made in the types of effluents that may be released
off-site; and there is no significant increase in public radiation
exposure. The NRC estimates the radiological dose to plant personnel
performing the inspections required by Code Case N-770 would be about 3
rems per plant over a 10-year interval, and a one-time exposure for
mitigating welds of about 30 rems per plant. As required by 10 CFR part
20, and in accordance with current plant procedures and radiation
protection programs, plant radiation protection staff will continue
monitoring dose rates and would make adjustments in shielding, access
requirements, decontamination methods, and procedures as necessary to
minimize the dose to workers. The increased occupational dose to
individual workers stemming from the Code Case N-770 inspections must
be maintained within the limits of 10 CFR part 20 and as low as
reasonably achievable. Therefore, the NRC concludes that the increase
in occupational exposure would not be significant. The proposed
rulemaking does not involve non-radiological plant effluents and has no
other environmental impact. Therefore, no significant non-radiological
impacts are associated with the proposed action. The determination of
this draft environmental assessment is that there will be no
significant off-site impact to the public from this action. However,
the NRC is seeking public comment of the draft environmental
assessment. Comments on any aspect of the environmental assessment may
be submitted to the NRC as indicated under the ADDRESSES heading of
this document.
IX. Paperwork Reduction Act Statement
The public burden for this information collection is estimated to
be a reduction of 120 hours, which is insignificant. Because the burden
for this information collection is insignificant, Office of Management
and Budget (OMB) clearance is not required. Existing requirements were
approved by the Office of Management and Budget, control number 3150-
0011.
This proposed rule would impose ASME Code Cases N-722-1 and N-770
which results in licensees having to revise their ISI programs and
procedures. The NRC estimates that the burden of preparing new ISI
program content and procedures is 40 person-hours per plant over the
next 3 years. This one-time burden affects 69 PWR plants, so the total
burden on an annual basis would be 920 hours. However, there are a
number of changes in the ASME Code edition and addenda associated with
this proposed rulemaking related to qualification of inspections in
Section XI, Appendix VIII. These changes would result in a one-time
reduction of about 5 relief requests per plant (104 PWR and BWR plants)
per 10-year ISI interval that would have otherwise been necessary.
Assuming 20 hours of licensee time to prepare each relief request
results in a one-time paperwork reduction of about 1,040 hours on an
annual basis. Overall, the burden on licensees for information
collection for this proposed rulemaking is reduced by 120 hours.
The NRC is seeking public comment on the potential impact of the
information collections contained in this proposed rule and on the
following issues:
1. Is the proposed information collection necessary for the proper
performance of the functions of the NRC, including whether the
information will have practical utility?
2. Is the estimate of burden accurate?
3. Is there a way to enhance the quality, utility, and clarity of
the information to be collected?
4. How can the burden of the information collection be minimized,
including the use of automated collection techniques?
A copy of the NRC Form 670, ``Information Required for Making an
Insignificant Burden Determination To Support a Decision That OMB
Clearance Is Not Required,'' may be viewed free of charge at the NRC
Public Document Room, One White Flint North, 11555 Rockville Pike, Room
O-1 F21, Rockville, MD 20852. The NRC Form 670 and rule are available
at the NRC worldwide Web site: http://www.nrc.gov/public-involve/doccomment/omb/index.html for 60 days after the signature date of this
notice.
[[Page 24351]]
Send comments on any aspect of these proposed information
collections, including suggestions for reducing the burden and on the
above issues, by June 3, 2010 to the Records and FOIA/Privacy Services
Branch (T-5 F52), U.S. Nuclear Regulatory Commission, Washington, DC
20555-0001, or by Internet electronic mail to
[email protected] and to Christine J. Kymn, the Desk
Officer, Office of Information and Regulatory Affairs, NEOB-10202
(3150-0011), Office of Management and Budget, Washington, DC 20503.
Comments received after this date will be considered if it is practical
to do so, but assurance of consideration cannot be given to comments
received after this date. You may also e-mail comments to
[email protected] or comment by telephone at 202-395-4638.
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.
X. Regulatory and Backfit Analysis
The NRC has prepared a Regulatory and Backfit Analysis on this
proposed rule. The analysis is available for review as indicated in
Section I, ``Submitting Comments and Accessing Information,'' of this
document.
XI. Regulatory Flexibility Certification
Under the Regulatory Flexibility Act of 1980 (5 U.S.C. 605(b)), the
NRC certifies that this proposed rule would not impose a significant
economical impact on a substantial number of small entities. This
proposed rule would affect only the licensing and operation of
commercial nuclear power plants. A licensee who is a subsidiary of a
large entity does not qualify as a small entity. 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), as the companies:
Provide services that are not engaged in manufacturing,
and have average gross receipts of more than $6.5 million over their
last 3 completed fiscal years, and have more than 500 employees;
Are not governments of a city, county, town, township or
village;
Are not school districts or special districts with
populations of less than 50; and
Are not small educational institutions.
List of Subjects in 10 CFR Part 50
Antitrust, Classified information, Criminal penalties, Fire
protection, Intergovernmental relations, Nuclear power plants and
reactors, Radiation protection, Reactor siting criteria, Reporting and
recordkeeping requirements.
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. 553, the NRC proposes to adopt
the following amendments to 10 CFR part 50.
PART 50--DOMESTIC LICENSING OF PRODUCTION AND UTILIZATION
FACILITIES
1. The authority citation for part 50 continues 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(dd), 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).
2. In Sec. 50.55a:
a. Revise paragraph (a), the introductory text of paragraphs (b)
and (b)(1), paragraphs (b)(1)(ii), (b)(1)(iii), and (b)(1)(iv); and add
paragraph (b)(1)(vii);
b. Revise paragraph (b)(2);
c. Revise the introductory text of paragraph (b)(3), paragraphs
(b)(3)(v), (b)(3)(vi), (c)(3), (d)(2), (e)(2), (f)(2), (f)(3)(v),
(f)(4), (f)(5)(iv), (g)(2), (g)(3), (g)(4), (g)(5)(iii), (g)(5)(iv),
(g)(6)(ii)(B), (g)(6)(ii)(E)(1), (g)(6)(ii)(E)(2), and
(g)(6)(ii)(E)(3);
d. Add paragraph (g)(6)(ii)(F); and
e. Revise footnote 1 to this section that appears after paragraph
(h)(3) to read as follows:
Sec. 50.55a Codes and standards.
* * * * *
(a) Quality standards, ASME Codes and IEEE standards, and
alternatives.
(1) Structures, systems, and components must be designed,
fabricated, erected, constructed, tested, and inspected to quality
standards commensurate with the importance of the safety function to be
performed.
(2) Systems and components of boiling and pressurized water-cooled
nuclear power reactors must meet the requirements of the ASME Boiler
and Pressure Vessel Code specified in paragraphs (b), (c), (d), (e),
(f), and (g) of this section. Protection systems of nuclear power
reactors of all types must meet the requirements specified in paragraph
(h) of this section.
(3) Proposed alternatives to the requirements of paragraphs (c),
(d), (e), (f), (g), and (h) of this section, or portions thereof, may
be used when authorized by the Director, Office of Nuclear Reactor
Regulation, or Director, Office of New Reactors, as appropriate. Any
proposed alternatives must be submitted and authorized prior to
implementation. The applicant or licensee shall demonstrate that:
(i) The proposed alternatives would provide an acceptable level of
quality and safety; or
(ii) Compliance with the specified requirements of this section
would result in hardship or unusual difficulty without a compensating
increase in the level of quality and safety.
(b) Standards approved for incorporation by reference. The
following standards have been approved for incorporation by reference
by the Director of the Federal Register pursuant to 5 U.S.C. 552(a) and
1 CFR Part 51: Section III, Division 1 (excluding Non-mandatory
Appendices) and Section XI, Division 1, of the ASME Boiler and Pressure
Vessel Code, and the ASME Code for Operation and Maintenance of Nuclear
Power Plants, which are referenced in paragraphs (b)(1), (b)(2), and
(b)(3) of this section; NRC Regulatory Guide 1.84, Revision 34,
``Design, Fabrication, and Materials Code Case Acceptability, ASME
Section III'' (October 2007), NRC Regulatory Guide 1.147, Revision 15,
``Inservice Inspection Code Case Acceptability, ASME Section XI,
Division 1'' (October 2007), and Regulatory Guide 1.192, ``Operation
and Maintenance Code Case Acceptability, ASME OM Code'' (June 2003),
which list ASME Code cases that
[[Page 24352]]
the NRC has approved in accordance with the requirements in paragraphs
(b)(4), (b)(5), and (b)(6) of this section; ASME Code Case N-722-1,
``Additional Examinations for PWR Pressure Retaining Welds in Class 1
Components Fabricated with Alloy 600/82/182 Materials, Section XI,
Division 1'' (ASME Approval Date: January 26, 2009), which has been
approved by the NRC with conditions in accordance with the requirements
in paragraph (g)(6)(ii)(E) of this section; ASME Code Case N-729-1,
``Alternative Examination Requirements for PWR Reactor Vessel Upper
Heads With Nozzles Having Pressure-Retaining Partial-Penetration Welds,
Section XI, Division 1'' (ASME Approval Date: March 28, 2006), which
has been approved by the NRC with conditions in accordance with the
requirements in paragraph (g)(6)(ii)(D) of this section; and ASME Code
Case N-770, ``Alternative Examination Requirements and Acceptance
Standards for Class 1 PWR Piping and Vessel Nozzle Butt Welds
Fabricated with UNS N06082 or UNS W86182 Weld Filler Material With or
Without Application of Listed Mitigation Activities, Section XI,
Division 1,'' (ASME Approval Date: January 26, 2009), which has been
approved by the NRC with conditions in accordance with the requirements
in paragraph (g)(6)(ii)(F) of this section. Copies of the ASME Boiler
and Pressure Vessel Code, the ASME Code for Operation and Maintenance
of Nuclear Power Plants, ASME Code Case N-722-1, ASME Code Case N-729-
1, and ASME Code Case N-770 may be purchased from the American Society
of Mechanical Engineers, Three Park Avenue, New York, NY 10016 or
through the Web http://www.asme.org/Codes/. Single copies of NRC
Regulatory Guides 1.84, Revision 34; 1.147, Revision 15; and 1.192 may
be obtained free of charge by writing the Reproduction and Distribution
Services Section, 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
Regulatory Guides 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 call 301-415-5610, 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.
(1) As used in this section, references to Section III refer to
Section III of the ASME Boiler and Pressure Vessel Code, and include
the 1963 Edition through 1973 Winter Addenda, and the 1974 Edition
(Division 1) through the 2008 Addenda (Division 1), subject to the
following conditions:
* * * * *
(ii) Weld leg dimensions. When applying the 1989 Addenda through
the latest edition and addenda incorporated by reference in paragraph
(b)(1) of this section, applicants or licensees may not apply
subparagraphs NB-3683.4(c)(1) and NB-3683.4(c)(2) or Footnote 11 from
the 1989 Addenda through the 2003 Addenda, or Footnote 13 from the 2004
Edition through the 2008 Addenda to Figures NC-3673.2(b)-1 and ND-
3673.2(b)-1 for welds with leg size less than 1.09 tn.
(iii) Seismic design of piping. Applicants or licensees may use
Subarticles NB-3200, NB-3600, NC-3600, and ND-3600 for seismic design
of piping, up to and including the 1993 Addenda, subject to the
condition specified in paragraph (b)(1)(ii) of this section. Applicants
or licensees may not use these subarticles for seismic design of piping
in the 1994 Addenda through the 2006 Addenda incorporated by reference
in paragraph (b)(1) of this section except that Subarticle NB-3200 in
the 2004 Edition through the 2008 Addenda may be used by applicants and
licensees subject to the condition in paragraph (b)(1)(iii)(B) of this
section. Applicants or licensees may use Subarticles NB-3600, NC-3600
and ND-3600 for the seismic design of piping in the 2006 Addenda
through the 2008 Addenda subject to the conditions of this paragraph
corresponding to these subarticles.
(A) For Class 1 elbows and tees of ferritic steel materials
operating at temperatures above 300 [deg]F, the allowable
B2' index defined in Subparagraph NB-3656(b)(3) shall be no
less than 0.75B2 from Table NB-3681(A)-1.
(B) When applying Note (1) of Figure NB-3222-1 for Level B service
limits, the calculation of Pb stresses must include
reversing dynamic loads (including inertia earthquake effects) if
evaluation of these loads is required.
(C) Do/t must not be greater than 40, where
Do is the outer diameter of pipe, and t is the nominal pipe
thickness. Subparagraph NB-3683.2(C), Note (1) to Table NB-3681(a)-1,
Note (3) to Figures NC-3673.2(b)-1 and ND-3673.2(b)-1 may not be
applied.
(iv) Quality assurance. When applying editions and addenda later
than the 1989 Edition of Section III, the requirements of NQA-1,
``Quality Assurance Requirements for Nuclear Facilities,'' 1986 Edition
through the 1994 Edition, are acceptable for use, provided that the
edition and addenda of NQA-1 specified in NCA-4000 is used in
conjunction with the administrative, quality, and technical provisions
contained in the edition and addenda of Section III being used.
* * * * *
(vii) Capacity certification and demonstration of function of
incompressible-fluid pressure-relief valves. When applying the 2006
Addenda through the 2008 Addenda, applicants or licensees may not apply
paragraph NB-7742 of the ASME B&PV Code, Section III. New Class 1
incompressible-fluid, pressure-relief valve designs must be tested at
the highest values of set-pressure ranges as required by prior editions
and addenda of the ASME B&PV Code, Section III.
(2) As used in this section, references to Section XI refer to
Section XI, Division 1, of the ASME Boiler and Pressure Vessel Code,
and include the 1970 Edition though the 1976 Winter Addenda, and the
1977 Edition through the 2007 Edition with the 2008 Addenda, subject to
the following conditions:
(i) Pressure-retaining welds in ASME Code Class 1 piping (applies
to Table IWB-2500 and IWB-2500-1 and Category B-J). If the facility's
application for a construction permit was docketed prior to July 1,
1978, the extent of examination for Code Class 1 pipe welds may be
determined by the requirements of Table IWB-2500 and Table IWB-2600
Category B-J of Section XI of the ASME B&PV Code in the 1974 Edition
and addenda through the Summer 1975 Addenda or other requirements the
NRC may adopt.
(ii) Effective edition and addenda of Subsection IWE and Subsection
IWL, Section XI. Applicants or licensees may use either the 1992
Edition with the 1992 Addenda or the 1995 Edition with the 1996 Addenda
of Subsection IWE and Subsection IWL as conditioned by the requirements
in paragraphs (b)(2)(iv) and (b)(2)(v) of this section when
implementing the initial 120-month inspection interval for the
containment inservice inspection requirements of this section.
Successive 120-month interval updates must be implemented in accordance
with paragraph (g)(4)(ii) of this section.
(iii) Section XI References to OM Part 4, OM Part 6 and OM Part 10
(Table
[[Page 24353]]
IWA-1600-1). When using Table IWA-1600-1, ``Referenced Standards and
Specifications,'' in the Section XI, Division 1, 1987 Addenda, 1988
Addenda, or 1989 Edition, the specified ``Revision Date or Indicator''
for ASME/ANSI OM Part 4, ASME/ANSI Part 6, and ASME/ANSI Part 10 must
be the OMa-1988 Addenda to the OM-1987 Edition. These requirements have
been incorporated into the OM Code which is incorporated by reference
in paragraph (b)(3) of this section.
(iv) Examination of concrete containments. Applicants or licensees
applying Subsection IWL, 1992 Edition with the 1992 Addenda, shall
apply paragraphs (b)(2)(iv)(A) of this section. Applicants or licensees
applying Subsection IWL, 1995 Edition with the 1996 Addenda, shall
apply paragraphs (b)(2)(iv)(A), (b)(2)(iv)(D)(3), and (b)(2)(iv)(E) of
this section. Applicants or licensees applying Subsection IWL, 1998
Edition through the 2000 Addenda shall apply paragraphs (b)(2)(iv)(E)
and (b)(2)(iv)(F) of this section. Applicants or licensees applying
Subsection IWL, 2001 Edition through the 2004 Edition, up to and
including the 2006 Addenda, shall apply paragraphs (b)(2)(iv)(E)
through (b)(2)(iv)(G) of this section. Applicants or licensees applying
Subsection IWL, 2007 Edition through the latest edition and addenda
incorporated by reference in paragraph (b)(2) of this section, shall
apply paragraph (b)(2)(iv)(E) of this section.
(A) Grease caps that are accessible must be visually examined to
detect grease leakage or grease cap deformations. Grease caps must be
removed for this examination when there is evidence of grease cap
deformation that indicates deterioration of anchorage hardware.
(B) When evaluation of consecutive surveillances of prestressing
forces for the same tendon or tendons in a group indicates a trend of
prestress loss such that the tendon force(s) would be less than the
minimum design prestress requirements before the next inspection
interval, an evaluation must be performed and reported in the
Engineering Evaluation Report as prescribed in IWL-3300.
(C) When the elongation corresponding to a specific load (adjusted
for effective wires or strands) during retensioning of tendons differs
by more than 10 percent from that recorded during the last measurement,
an evaluation must be performed to determine whether the difference is
related to wire failures or slip of wires in anchorage. A difference of
more than 10 percent must be identified in the ISI Summary Report
required by IWA-6000.
(D) The applicant or licensee shall report the following
conditions, if they occur, in the ISI Summary Report required by IWA-
6000:
(1) The sampled sheathing filler grease contains chemically
combined water exceeding 10 percent by weight or the presence of free
water;
(2) The absolute difference between the amount removed and the
amount replaced exceeds 10 percent of the tendon net duct volume;
(3) Grease leakage is detected during general visual examination of
the containment surface.
(E) For Class CC applications, the applicant or licensee shall
evaluate the acceptability of inaccessible areas when conditions exist
in accessible areas that could indicate the presence of or result in
degradation to such inaccessible areas. For each inaccessible area
identified, the applicant or licensee shall provide the following in
the ISI Summary Report required by IWA-6000:
(1) A description of the type and estimated extent of degradation,
and the conditions that led to the degradation;
(2) An evaluation of each area, and the result of the evaluation,
and;
(3) A description of necessary corrective actions.
(F) Personnel that examine containment concrete surfaces and tendon
hardware, wires, or strands must meet the qualification provisions in
IWA-2300. The ``owner-defined'' personnel qualification provisions in
IWL-2310(d) are not approved for use.
(G) Corrosion protection material must be restored following
concrete containment post-tensioning system repair and replacement
activities in accordance with the quality assurance program
requirements specified in IWA-1400.
(v) Examination of metal containments and the liners of concrete
containments. Applicants or licensees applying Subsection IWE, 1992
Edition with the 1992 Addenda, or the 1995 Edition with the 1996
Addenda, shall satisfy the requirements of paragraphs (b)(2)(v)(A)
through (b)(2)(v)(E) of this section. Applicants or licensees applying
Subsection IWE, 1998 Edition through the 2001 Edition with the 2003
Addenda, shall satisfy the requirements of paragraphs (b)(2)(v)(A),
(b)(2)(v)(B), and (b)(2)(v)(F) through (b)(2)(v)(I) of this section.
Applicants or licensees applying Subsection IWE, 2004 Edition, up to
and including, the 2005 Addenda, shall satisfy the requirements of
paragraphs (b)(2)(v)(A), (b)(2)(v)(B), and (b)(2)(v)(F) through
(b)(2)(v)(H) of this section. Applicants or licensees Licensees
applying Subsection IWE, 2004 Edition with the 2006 Addenda, shall
satisfy the requirements of paragraphs (b)(2)(v)(A) and (b)(2)(v)(B) of
this section. Applicants or licensees applying Subsection IWE, 2007
Edition through the latest addenda incorporated by reference in
paragraph (b)(2) of this section, shall satisfy the requirements of
paragraphs (b)(2)(v)(A), (b)(2)(v)(B) and (b)(2)(v)(J) of this section.
(A) For Class MC applications, the applicant or licensee shall
evaluate the acceptability of inaccessible areas when conditions exist
in accessible areas that could indicate the presence of or result in
degradation to such inaccessible areas. For each inaccessible area
identified, the applicant or licensee shall provide the following in
the ISI Summary Report as required by IWA-6000:
(1) A description of the type and estimated extent of degradation,
and the conditions that led to the degradation;
(2) An evaluation of each area, and the result of the evaluation,
and;
(3) A description of necessary corrective actions.
(B) When performing remotely the visual examinations required by
Subsection IWE, the maximum direct examination distance specified in
Table IWA-2210-1 may be extended and the minimum illumination
requirements specified in Table IWA-2210-1 may be decreased provided
that the conditions or indications for which the visual examination is
performed can be detected at the chosen distance and illumination.
(C) The examinations specified in Examination Category E-B,
Pressure Retaining Welds, and Examination Category E-F, Pressure
Retaining Dissimilar Metal Welds, are optional.
(D) Paragraph (b)(2)(v)(D) of this section may be used as an
alternative to the requirements of IWE-2430.
(1) If the examinations reveal flaws or areas of degradation
exceeding the acceptance standards of Table IWE-3410-1, an evaluation
must be performed to determine whether additional component
examinations are required. For each flaw or area of degradation
identified which exceeds acceptance standards, the applicant or
licensee shall provide the following in the ISI Summary Report required
by IWA-6000:
(i) A description of each flaw or area, including the extent of
degradation, and the conditions that led to the degradation;
(ii) The acceptability of each flaw or area, and the need for
additional examinations to verify that similar
[[Page 24354]]
degradation does not exist in similar components, and;
(iii) A description of necessary corrective actions.
(2) The number and type of additional examinations to ensure
detection of similar degradation in similar components.
(E) A general visual examination as required by Subsection IWE must
be performed once each period.
(F) VT-1 and VT-3 examinations must be conducted in accordance with
IWA-2200. Personnel conducting examinations in accordance with the VT-1
or VT-3 examination method shall be qualified in accordance with IWA-
2300. The ``owner-defined'' personnel qualification provisions in IWE-
2330(a) for personnel that conduct VT-1 and VT-3 examinations are not
approved for use.
(G) The VT-3 examination method must be used to conduct the
examinations in Items E1.12 and E1.20 of Table IWE-2500-1, and the VT-1
examination method must be used to conduct the examination in Item
E4.11 of Table IWE-2500-1. An examination of the pressure-retaining
bolted connections in Item E1.11 of Table IWE-2500-1 using the VT-3
examination method must be conducted once each interval. The ``owner-
defined'' visual examination provisions in IWE-2310(a) are not approved
for use for VT-1 and VT-3 examinations.
(H) Containment bolted connections that are disassembled during the
scheduled performance of the examinations in Item E1.11 of Table IWE-
2500-1 must be examined using the VT-3 examination method. Flaws or
degradation identified during the performance of a VT-3 examination
must be examined in accordance with the VT-1 examination method. The
criteria in the material specification or IWB-3517.1 must be used to
evaluate containment bolting flaws or degradation. As an alternative to
performing VT-3 examinations of containment bolted connections that are
disassembled during the scheduled performance of Item E1.11, VT-3
examinations of containment bolted connections may be conducted
whenever containment bolted connections are disassembled for any
reason.
(I) The ultrasonic examination acceptance standard specified in
IWE-3511.3 for Class MC pressure-retaining components must also be
applied to metallic liners of Class CC pressure-retaining components.
(J) In general, the cutting of a large hole in the containment
pressure boundary for replacement of steam generators, reactor vessel
heads, pressurizers, or other similar modification is considered a
``major'' modification or repair/replacement for Class MC and Class CC
containment structures. When applying IWE-5000, any repair/replacement
that is a ``major'' containment modification, as defined in this
section, must be followed by a Type A test to provide assurance of
containment structural and leaktight integrity prior to returning to
service, in accordance with 10 CFR part 50, appendix J, Option A or
Option B on which the applicant's or licensee's Containment Leak-Rate
Testing Program is based. When applying IWE-5000, if a Type A, B, or C
Test is performed, the acceptance standard for the test must be in
accordance with 10 CFR part 50, appendix J. In lieu of performing the
Type A test, the applicant or licensee may conduct a short-duration
structural test of the containment, which is a combination of actions
to ensure that:
(1) The modified containment meets the pre-service non-destructive
examination (NDE) test requirements as required by the construction
code;
(2) The locally welded areas are examined for essentially zero
leakage using a soap bubble test, or an equivalent test;
(3) The entire containment is subjected to the peak calculated
containment design basis accident pressure, Pa, for a
minimum of 10 minutes (Class MC steel containment) and 1 hour (Class CC
concrete containment); and
(4) The outside surfaces of concrete containments are visually
examined as required by Subsection IWL, during the peak pressure, and
that the outside and inside surfaces of the steel containment surfaces
are examined as required by Subsection IWE, during or immediately after
the test.
(vi) Quality assurance. When applying Section XI editions and
addenda later than the 1989 Edition, the requirements of NQA-1,
``Quality Assurance Requirements for Nuclear Facilities,'' 1979 Addenda
through the 1989 Edition, are acceptable as permitted by IWA-1400 of
Section XI, if the licensee uses its 10 CFR part 50, appendix B,
quality assurance program, in conjunction with Section XI requirements.
Commitments contained in the licensee's quality assurance program
description that are more stringent than those contained in NQA-1 must
govern Section XI activities. Further, where NQA-1 and Section XI do
not address the commitments contained in the licensee's Appendix B
quality assurance program description, the commitments must be applied
to Section XI activities.
(vii) [Reserved]
(viii) Underwater welding. The provisions in IWA-4660, ``Underwater
Welding,'' of Section XI, 1997 Addenda through the latest edition and
addenda incorporated by reference in paragraph (b)(2) of this section,
are not approved for use on irradiated material.
(ix) [Reserved]
(x) Appendix VIII personnel qualification. All personnel qualified
for performing ultrasonic examinations in accordance with Appendix VIII
shall receive 8 hours of annual hands-on training on specimens that
contain cracks. Licensees applying the 1999 Addenda through the latest
edition and addenda incorporated by reference in paragraph (b)(2) of
this section may use the annual practice requirements in VII-4240 of
Appendix VII of Section XI in place of the 8 hours of annual hands-on
training provided that the supplemental practice is performed on
material or welds that contain cracks, or by analyzing prerecorded data
from material or welds that contain cracks. In either case, training
must be completed no earlier than 6 months prior to performing
ultrasonic examinations at a licensee's facility.
(xi) Appendix VIII specimen set and qualification requirements.
Licensees using Appendix VIII in the 1995 Edition through the 2001
Edition of the ASME Boiler and Pressure Vessel Code may elect to comply
with all of the provisions in paragraphs (b)(2)(xi)(A) through
(b)(2)(xi)(M) of this section, except for paragraph (b)(2)(xi)(F) of
this section, which may be used at the licensee's option. Licensees
using editions and addenda after 2001 Edition through the 2006 Addenda
shall use the 2001 Edition of Appendix VIII, and may elect to comply
with all of the provisions in paragraphs (b)(2)(xi)(A) through
(b)(2)(xi)(M) of this section, except for paragraph (b)(2)(xi)(F) of
this section, which may be used at the licensee's option.
(A) When applying Supplements 2, 3, and 10 to Appendix VIII, the
following examination coverage criteria requirements must be used:
(1) Piping must be examined in two axial directions, and when
examination in the circumferential direction is required, the
circumferential examination must be performed in two directions,
provided access is available. Dissimilar metal welds must be examined
axially and circumferentially.
(2) Where examination from both sides is not possible, full
coverage credit may be claimed from a single side for ferritic welds.
Where examination from
[[Page 24355]]
both sides is not possible on austenitic welds or dissimilar metal
welds, full coverage credit from a single side may be claimed only
after completing a successful single-sided Appendix VIII demonstration
using flaws on the opposite side of the weld. Dissimilar metal weld
qualifications must be demonstrated from the austenitic side of the
weld and may be used to perform examinations from either side of the
weld.
(B) The following conditions must be used in addition to the
requirements of Supplement 4 to Appendix VIII:
(1) Paragraph 3.1, Detection acceptance criteria--Personnel are
qualified for detection if the results of the performance demonstration
satisfy the detection requirements of ASME Section XI, Appendix VIII,
Table VIII-S4-1 and no flaw greater than 0.25 inch through wall
dimension is missed.
(2) Paragraph 1.1(c), Detection test matrix--Flaws smaller than the
50 percent of allowable flaw size, as defined in IWB-3500, need not be
included as detection flaws. For procedures applied from the inside
surface, use the minimum thickness specified in the scope of the
procedure to calculate a/t. For procedures applied from the outside
surface, the actual thickness of the test specimen is to be used to
calculate a/t.
(C) When applying Supplement 4 to Appendix VIII, the following
conditions must be used:
(1) A depth sizing requirement of 0.15 inch RMS must be used in
lieu of the requirements in Subparagraphs 3.2(a) and 3.2(c), and a
length sizing requirement of 0.75 inch RMS must be used in lieu of the
requirement in Subparagraph 3.2(b).
(2) In lieu of the location acceptance criteria requirements of
Subparagraph 2.1(b), a flaw will be considered detected when reported
within 1.0 inch or 10 percent of the metal path to the flaw, whichever
is greater, of its true location in the X and Y directions.
(3) In lieu of the flaw type requirements of Subparagraph
1.1(e)(1), a minimum of 70 percent of the flaws in the detection and
sizing tests shall be cracks. Notches, if used, must be limited by the
following:
(i) Notches must be limited to the case where examinations are
performed from the clad surface.
(ii) Notches must be semielliptical with a tip width of less than
or equal to 0.010 inches.
(iii) Notches must be perpendicular to the surface within 2 degrees.
(4) In lieu of the detection test matrix requirements in paragraphs
1.1(e)(2) and 1.1(e)(3), personnel demonstration test sets must contain
a representative distribution of flaw orientations, sizes, and
locations.
(D) The following conditions must be used in addition to the
requirements of Supplement 6 to Appendix VIII:
(1) Paragraph 3.1, Detection Acceptance Criteria--Personnel are
qualified for detection if:
(i) No surface connected flaw greater than 0.25 inch through wall
has been missed.
(ii) No embedded flaw greater than 0.50 inch through wall has been
missed.
(2) Paragraph 3.1, Detection Acceptance Criteria--For procedure
qualification, all flaws within the scope of the procedure are
detected.
(3) Paragraph 1.1(b) for detection and sizing test flaws and
locations--Flaws smaller than the 50 percent of allowable flaw size, as
defined in IWB-3500, need not be included as detection flaws. Flaws
which are less than the allowable flaw size, as defined in IWB-3500,
may be used as detection and sizing flaws.
(4) Notches are not permitted.
(E) When applying Supplement 6 to Appendix VIII, the following
conditions must be used:
(1) A depth sizing requirement of 0.25 inch RMS must be used in
lieu of the requirements of subparagraphs 3.2(a), 3.2(c)(2), and
3.2(c)(3).
(2) In lieu of the location acceptance criteria requirements in
Subparagraph 2.1(b), a flaw will be considered detected when reported
within 1.0 inch or 10 percent of the metal path to the flaw, whichever
is greater, of its true location in the X and Y directions.
(3) In lieu of the length sizing criteria requirements of
Subparagraph 3.2(b), a length sizing acceptance criteria of 0.75 inch
RMS must be used.
(4) In lieu of the detection specimen requirements in Subparagraph
1.1(e)(1), a minimum of 55 percent of the flaws must be cracks. The
remaining flaws may be cracks or fabrication type flaws, such as slag
and lack of fusion. The use of notches is not allowed.
(5) In lieu of paragraphs 1.1(e)(2) and 1.1(e)(3) detection test
matrix, personnel demonstration test sets must contain a representative
distribution of flaw orientations, sizes, and locations.
(F) The following conditions may be used for personnel
qualification for combined Supplement 4 to Appendix VIII and Supplement
6 to Appendix VIII qualification. Licensees choosing to apply this
combined qualification shall apply all of the provisions of Supplements
4 and 6 including the following conditions:
(1) For detection and sizing, the total number of flaws must be at
least 10. A minimum of 5 flaws shall be from Supplement 4, and a
minimum of 50 percent of the flaws must be from Supplement 6. At least
50 percent of the flaws in any sizing must be cracks. Notches are not
acceptable for Supplement 6.
(2) Examination personnel are qualified for detection and length
sizing when the results of any combined performance demonstration
satisfy the acceptance criteria of Supplement 4 to Appendix VIII.
(3) Examination personnel are qualified for depth sizing when
Supplement 4 to Appendix VIII and Supplement 6 to Appendix VIII flaws
are sized within the respective acceptance criteria of those
supplements.
(G) When applying Supplement 4 to Appendix VIII, Supplement 6 to
Appendix VIII, or combined Supplement 4 and Supplement 6 qualification,
the following additional conditions must be used, and examination
coverage must include:
(1) The clad to base metal interface, including a minimum of 15
percent T (measured from the clad to base metal interface), must be
examined from four orthogonal directions using procedures and personnel
qualified in accordance with Supplement 4 to Appendix VIII.
(2) If the clad-to-base-metal-interface procedure demonstrates
delectability of flaws with a tilt angle relative to the weld
centerline of at least 45 degrees, the remainder of the examination
volume is considered fully examined if coverage is obtained in one
parallel and one perpendicular direction. This must be accomplished
using a procedure and personnel qualified for single-side examination
in accordance with Supplement 6. Subsequent examinations of this volume
may be performed using examination techniques qualified for a tilt
angle of at least 10 degrees.
(3) The examination volume not addressed by paragraph
(b)(2)(xi)(G)(1) of this section is considered fully examined if
coverage is obtained in one parallel and one perpendicular direction,
using a procedure and personnel qualified for single sided examination
when the conditions in paragraph (b)(2)(xi)(G)(2) are met.
(H) When applying Supplement 5 to Appendix VIII, at least 50
percent of the flaws in the demonstration test set must be cracks and
the maximum mis-orientation must be demonstrated with cracks. Flaws in
nozzles with bore diameters equal to or less than 4 inches may be
notches.
(I) When applying Supplement 5, Paragraph (a), to Appendix VIII,
the number of false calls allowed must be
[[Page 24356]]
D/10, with a maximum of 3, where D is the diameter of the nozzle.
(J) [Reserved]
(K) When performing nozzle-to-vessel weld examinations, the
following conditions must be used when the requirements contained in
Supplement 7 to Appendix VIII are applied for nozzle-to-vessel welds in
conjunction with Supplement 4 to Appendix VIII, Supplement 6 to
Appendix VIII, or combined Supplement 4 and Supplement 6 qualification.
(1) For examination of nozzle-to-vessel welds conducted from the
bore, the following conditions are required to qualify the procedures,
equipment, and personnel:
(i) For detection, a minimum of four flaws in one or more full-
scale nozzle mock-ups must be added to the test set. The specimens must
comply with Supplement 6, paragraph 1.1, to Appendix VIII, except for
flaw locations specified in Table VIII S6-1. Flaws may be notches,
fabrication flaws or cracks. Seventy-five (75) percent of the flaws
must be cracks or fabrication flaws. Flaw locations and orientations
must be selected from the choices shown in paragraph (b)(2)(xi)(K)(4)
of this section, Table VIII-S7-1--Modified, with the exception that
flaws in the outer eighty-five (85) percent of the weld need not be
perpendicular to the weld. There may be no more than two flaws from
each category, and at least one subsurface flaw must be included.
(ii) For length sizing, a minimum of four flaws as in paragraph
(b)(2)(xi)(K)(1)(i) of this section must be included in the test set.
The length sizing results must be added to the results of combined
Supplement 4 to Appendix VIII and Supplement 6 to Appendix VIII. The
combined results must meet the acceptance standards contained in
paragraph (b)(2)(xi)(E)(3) of this section.
(iii) For depth sizing, a minimum of four flaws as in paragraph
(b)(2)(xi)(K)(1)(i) of this section must be included in the test set.
Their depths must be distributed over the ranges of Supplement 4,
Paragraph 1.1, to Appendix VIII, for the inner 15 percent of the wall
thickness and Supplement 6, Paragraph 1.1, to Appendix VIII, for the
remainder of the wall thickness. The depth sizing results must be
combined with the sizing results from Supplement 4 to Appendix VIII for
the inner 15 percent and to Supplement 6 to Appendix VIII for the
remainder of the wall thickness. The combined results must meet the
depth sizing acceptance criteria contained in paragraphs
(b)(2)(xi)(C)(1), (b)(2)(xi)(E)(1), and (b)(2)(xi)(F)(3) of this
section.
(2) For examination of reactor pressure vessel nozzle-to-vessel
welds conducted from the inside of the vessel,
(i) The clad to base metal interface and the adjacent examination
volume to a minimum depth of 15 percent T (measured from the clad to
base metal interface) must be examined from four orthogonal directions
using a procedure and personnel qualified in accordance with Supplement
4 to Appendix VIII as conditioned by paragraphs (b)(2)(xi)(B) and
(b)(2)(xi)(C) of this section.
(ii) When the examination volume defined in paragraph
(b)(2)(xi)(K)(2)(i) of this section cannot be effectively examined in
all four directions, the examination must be augmented by examination
from the nozzle bore using a procedure and personnel qualified in
accordance with paragraph (b)(2)(xi)(K)(1) of this section.
(iii) The remainder of the examination volume not covered by
paragraph (b)(2)(xi)(K)(2)(ii) of this section or a combination of
paragraphs (b)(2)(xi)(K)(2)(i) and (b)(2)(xi)(K)(2)(ii) of this
section, must be examined from the nozzle bore using a procedure and
personnel qualified in accordance with paragraph (b)(2)(xi)(K)(1) of
this section, or from the vessel shell using a procedure and personnel
qualified for single sided examination in accordance with Supplement 6
to Appendix VIII, as conditioned by paragraphs (b)(2)(xi)(D) through
(b)(2)(xi)(G) of this section.
(3) For examination of reactor pressure vessel nozzle-to-shell
welds conducted from the outside of the vessel,
(i) The clad to base metal interface and the adjacent metal to a
depth of 15 percent T, (measured from the clad to base metal interface)
must be examined from one radial and two opposing circumferential
directions using a procedure and personnel qualified in accordance with
Supplement 4 to Appendix VIII, as conditioned by paragraphs
(b)(2)(xi)(B) and (b)(2)(xi)(C) of this section, for examinations
performed in the radial direction, and Supplement 5 to Appendix VIII,
as conditioned by paragraph (b)(2)(xi)(J) of this section, for
examinations performed in the circumferential direction.
(ii) The examination volume not addressed by paragraph
(b)(2)(xi)(K)(3)(i) of this section must be examined in a minimum of
one radial direction using a procedure and personnel qualified for
single sided examination in accordance with Supplement 6 to Appendix
VIII, as conditioned by paragraphs (b)(2)(xi)(D) through (b)(2)(xi)(G)
of this section.
(4) Table VIII-S7-1, ``Flaw Locations and Orientations,''
Supplement 7 to Appendix VIII, is conditioned as follows:
Table VIII-S7-1--Modified
----------------------------------------------------------------------------------------------------------------
Flaw Locations and Orientations
-----------------------------------------------------------------------------------------------------------------
Parallel to weld Perpendicular to weld
----------------------------------------------------------------------------------------------------------------
Inner 15 percent............................................ X X
OD Surface.................................................. X ........................
Subsurface.................................................. X ........................
----------------------------------------------------------------------------------------------------------------
(L) As a condition to the requirements of Supplement 8,
Subparagraph 1.1(c), to Appendix VIII, notches may be located within
one diameter of each end of the bolt or stud.
(M) When implementing Supplement 12 to Appendix VIII, only the
provisions related to the coordinated implementation of Supplement 3 to
Supplement 2 performance demonstrations are to be applied.
(xii) Appendix VIII single side ferritic vessel and piping and
stainless steel piping examination.
(A) Examinations performed from one side of a ferritic vessel weld
must be conducted with equipment, procedures, and personnel that have
demonstrated proficiency with single side examinations. To demonstrate
equivalency to two sided examinations, the demonstration must be
performed to the requirements of Appendix VIII as conditioned by this
paragraph and paragraphs (b)(2)(xi)(B) through (b)(2)(xi)(G) of this
section, on specimens containing flaws with non-optimum sound energy
reflecting
[[Page 24357]]
characteristics or flaws similar to those in the vessel being examined.
(B) Examinations performed from one side of a ferritic or stainless
steel pipe weld must be conducted with equipment, procedures, and
personnel that have demonstrated proficiency with single side
examinations. To demonstrate equivalency to two sided examinations, the
demonstration must be performed to the requirements of Appendix VIII as
conditioned by this paragraph and paragraph (b)(2)(xi)(A) of this
section.
(xiii) Reconciliation of quality requirements. When purchasing
replacement items, in addition to the reconciliation provisions of IWA-
4200, 1995 Addenda through 1998 Edition, the replacement items must be
purchased, to the extent necessary, in accordance with the licensee's
quality assurance program description required by 10 CFR
50.34(b)(6)(ii).
(xiv) Certification of NDE personnel. (A) Level I and II
nondestructive examination personnel shall be recertified on a 3-year
interval in lieu of the 5-year interval specified in the 1997 Addenda
and 1998 Edition of IWA-2314, and IWA-2314(a) and IWA-2314(b) of the
1999 Addenda through the latest edition and addenda incorporated by
reference in paragraph (b)(2) of this section.
(B) When applying editions and addenda prior to the 2007 Edition of
Section XI, paragraph IWA-2316 may only be used to qualify personnel
that observe leakage during system leakage and hydrostatic tests
conducted in accordance with IWA 5211(a) and (b).
(C) When applying editions and addenda prior to the 2004 Edition
through the 2005 Addenda of Section XI, licensee's qualifying visual
examination personnel for VT-3 visual examination under paragraph IWA-
2317 of Section XI, must demonstrate the proficiency of the training by
administering an initial qualification examination and administering
subsequent examinations on a 3-year interval.
(xv) Substitution of alternative methods. The provisions for
substituting alternative examination methods, a combination of methods,
or newly developed techniques in the 1997 Addenda of IWA-2240 must be
applied when using the 1998 Edition through the 2004 Edition of Section
XI of the ASME B&PV Code. The provisions in IWA-4520(c), 1997 Addenda
through the 2004 Edition, allowing the substitution of alternative
methods, a combination of methods, or newly developed techniques for
the methods specified in the Construction Code are not approved for
use. The provisions in IWA-4520(b)(2) and IWA-4521 of the 2008 Addenda
through the latest edition and addenda approved in paragraph (b)(2) of
this section, allowing the substitution of ultrasonic examination for
radiographic examination specified in the Construction Code are not
approved for use.
(xvi) System leakage tests.
(A) When performing system leakage tests in accordance with IWA-
5213(a), 1997 through 2002 Addenda, the licensee shall maintain a 10-
minute hold time after test pressure has been reached for Class 2 and
Class 3 components that are not in use during normal operating
conditions. No hold time is required for the remaining Class 2 and
Class 3 components provided that the system has been in operation for
at least 4 hours for insulated components or 10 minutes for uninsulated
components.
(B) The NDE provision in IWA-4540(a)(2) of the 2002 Addenda of
Section XI must be applied when performing system leakage tests after
repair and replacement activities performed by welding or brazing on a
pressure retaining boundary using the 2003 Addenda through the latest
edition and addenda incorporated by reference in paragraph (b)(2) of
this section.
(xvii) Table IWB-2500-1 examination requirements.
(A) The provisions of Table IWB-2500-1, Examination Category B-D,
Full Penetration Welded Nozzles in Vessels, Items B3.40 and B3.60
(Inspection Program A) and Items B3.120-and B3.140 (Inspection Program
B) of the 1998 Edition must be applied when using the 1999 Addenda
through the latest edition and addenda incorporated by reference in
paragraph (b)(2) of this section. A visual examination with
magnification that has a resolution sensitivity to detect a 1-mil width
wire or crack, utilizing the allowable flaw length criteria in Table
IWB-3512-1, 1997 Addenda through the latest edition and addenda
incorporated by reference in paragraph (b)(2) of this section, with a
limiting assumption on the flaw aspect ratio (i.e., a/l=0.5), may be
performed instead of an ultrasonic examination.
(B) The provisions of Table IWB-2500-1, Examination Category B-G-2,
Item B7.80, that are in the 1995 Edition are applicable only to reused
bolting when using the 1997 Addenda through the latest edition and
addenda incorporated by reference in paragraph (b)(2) of this section.
(xviii) Surface examination. The use of the provision in IWA-2220,
``Surface Examination,'' of Section XI, 2001 Edition through the latest
edition and addenda incorporated by reference in paragraph (b)(2) of
this section, that allow use of an ultrasonic examination method is
prohibited.
(xix) Evaluation of thermally cut surfaces. The use of the
provisions for eliminating mechanical processing of thermally cut
surfaces in IWA-4461.4.2 of Section XI, 2001 Edition through the latest
edition and addenda incorporated by reference in paragraph (b)(2) of
this section are prohibited.
(xx) Incorporation of the performance demonstration initiative and
addition of ultrasonic examination criteria. The use of Appendix VIII
and the supplements to Appendix VIII and Article I-3000 of Section XI
of the ASME B&PV Code, 2002 Addenda through the 2006 Addenda is
prohibited.
(xxi) Mitigation of defects by modification. The use of the
provisions in IWA-4340, ``Mitigation of Defects by Modification,''
Section XI, 2001 Edition through the latest edition and addenda
incorporated by reference in paragraph (b)(2) of this section are
prohibited.
(xxii) Pressure testing Class 1, 2, and 3 mechanical joints. The
repair and replacement activity provisions in IWA-4540(c) of the 1998
Edition of Section XI for pressure testing Class 1, 2, and 3 mechanical
joints must be applied when using the 2001 Edition through the latest
edition and addenda incorporated by reference in paragraph (b)(2) of
this section.
(xxiii) Removal of insulation. When performing visual examination
in accordance with IWA-5242 of Section XI of the ASME B&PV Code, 2003
Addenda through the 2006 Addenda, or IWA-5241 of the 2007 Edition
through the latest edition and addenda incorporated in paragraph (b)(2)
of the section, insulation must be removed from 17-4 PH or 410
stainless steel studs or bolts aged at a temperature below 1100[deg]F
or having a Rockwell Method C hardness value above 30, and from A-286
stainless steel studs or bolts preloaded to 100,000 pounds per square
inch or higher.
(xxiv) Analysis of flaws. Licensees using ASME B&PV Code, Section
XI, Appendix A shall use the following conditions when implementing
Equation (2) in A-4300(b)(1):
For R < 0, [Delta]KI depends on the crack depth (a),
and the flow stress ([sigma]f). The flow stress is
defined by [sigma]f = \1/2\([sigma]ys +
[sigma]ult), where [sigma]ys is the yield
strength and [sigma]ult is the ultimate tensile strength
in units ksi (MPa) and a is in units in. (mm). For -2 <= R <= 0 and
Kmax - Kmin <= 0.8 x 1.12 [sigma]f
[radic]([pi]a), S = 1 and [Delta]KI = Kmax.
For R < -2 and Kmax - Kmin <= 0.8 x 1.12
[sigma]f [radic]([pi]a), S = 1 and [Delta]KI =
(1-R) Kmax/3. For R < 0 and Kmax -
Kmin > 0.8 x 1.12 [sigma]f [radic]([pi]a), S =
1 and [Delta]KI = Kmax - Kmin.
[[Page 24358]]
(xxv) Evaluation of unanticipated operating events. The provisions
of ASME B&PV Code, Section XI, Appendix E, Section E-1200 are not
approved for use. In addition, when using the provisions of Section E-
1300, the analytical procedure must be based on a postulated semi-
elliptical surface flaw of a one-quarter vessel thickness (i.e., the
``minimum initiation crack size'' in Table E-2 shall be a 1/4T flaw)
and the linear elastic fracture mechanics criteria be as follows:
1.4KIm + KIr = KIc for the LTOP
condition, and 1.4KIm + KIt + KIr =
KIc, for the PTT condition
(xxvi) Nonmandatory Appendix R. Nonmandatory Appendix R, ``Risk-
Informed Inspection Requirements for Piping,'' of Section XI, 2005
Addenda through the latest edition and addenda incorporated by
reference in paragraph (b)(2) of this section, may not be implemented
without prior NRC authorization of the proposed alternative in
accordance with paragraph (a)(3)(i) of this section.
(3) As used in this section, references to the OM Code refer to the
ASME Code for Operation and Maintenance of Nuclear Power Plants,
Subsections ISTA, ISTB, ISTC, and ISTD, Mandatory Appendices I and II,
and Nonmandatory Appendices A through H and J, and include the 1995
Edition through the 2006 Addenda subject to the following conditions:
* * * * *
(v) Subsection ISTD. Article IWF-5000, ``Inservice Inspection
Requirements for Snubbers,'' of the ASME B&PV Code, Section XI, must be
used when performing inservice inspection examinations and tests of
snubbers at nuclear power plants.
(A) Licensees may use Subsection ISTD, ``Preservice and Inservice
Examination and Testing of Dynamic Restraints (Snubbers) in Light-Water
Reactor Power Plants,'' ASME OM Code, 1995 Edition through the latest
edition and addenda incorporated by reference in paragraph (b)(3) of
this section, in place of the requirements for snubbers in the editions
and addenda up to the 2005 Addenda of the ASME B&PV Code, Section XI,
IWF-5200(a) and (b) and IWF-5300(a) and (b), by making appropriate
changes to their technical specifications or licensee-controlled
documents. Preservice and inservice examinations must be performed
using the VT-3 visual examination method described in IWA-2213.
(B) Licensees shall comply with the provisions for examining and
testing snubbers in Subsection ISTD of the ASME OM Code and make
appropriate changes to their technical specifications or licensee-
controlled documents when using the 2006 Addenda and later editions and
addenda of Section XI of the ASME B&PV Code.
(vi) Exercise interval for manual valves. Manual valves must be
exercised on a 2-year interval rather that the 5-year interval
specified in paragraph ISTC-3540 of the 1999 through the 2005 Addenda
of the ASME OM Code, provided that adverse conditions do not require
more frequent testing.
* * * * *
(c) * * *
(3) The Code edition, addenda, and optional ASME Code cases to be
applied to components of the reactor coolant pressure boundary must be
determined by the provisions of paragraph NCA-1140, Subsection NCA of
Section III of the ASME Boiler and Pressure Vessel Code, subject to the
following conditions:
(i) The edition and addenda applied to a component must be those
which are incorporated by reference in paragraph (b)(1) of this
section;
(ii) The ASME Code provisions applied to the pressure vessel may be
dated no earlier than the Summer 1972 Addenda of the 1971 edition;
(iii) The ASME Code provisions applied to piping, pumps, and valves
may be dated no earlier than the Winter 1972 Addenda of the 1971
edition; and
(iv) The optional Code cases applied to a component must be those
listed in NRC Regulatory Guide 1.84 that is incorporated by reference
in paragraph (b) of this section.
* * * * *
(d) * * *
(2) The Code edition, addenda, and optional ASME Code cases to be
applied to the systems and components identified in paragraph (d)(1) of
this section must be determined by the rules of paragraph NCA-1140,
Subsection NCA of Section III of the ASME Boiler and Pressure Vessel
Code, subject to the following conditions:
(i) The edition and addenda must be those which are incorporated by
reference in paragraph (b)(1) of this section;
(ii) The ASME Code provisions applied to the systems and components
may be dated no earlier than the 1980 Edition; and
(iii) The optional Code cases must be those listed in the NRC
Regulatory Guide 1.84 that is incorporated by reference in paragraph
(b) of this section.
(e) * * *
(2) The Code edition, addenda, and optional ASME Code cases to be
applied to the systems and components identified in paragraph (e)(1) of
this section must be determined by the rules of paragraph NCA-1140,
subsection NCA of Section III of the ASME Boiler and Pressure Vessel
Code, subject to the following conditions:
(i) The edition and addenda must be those which are incorporated by
reference in paragraph (b)(1) of this section;
(ii) The ASME Code provisions applied to the systems and components
may be dated no earlier than the 1980 Edition; and
(iii) The optional Code cases must be those listed in NRC
Regulatory Guide 1.84 that is incorporated by reference in paragraph
(b) of this section.
(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 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 Regulatory Guide
1.147, Revision 15, or 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
Regulatory Guide 1.147, Revision 15, or 1.192 that are incorporated by
reference in paragraph (b) of this section), subject to the applicable
conditions listed therein.
(3) * * *
(v) All pumps and valves may meet the test requirements set forth
in subsequent editions of codes and addenda or portions thereof which
are incorporated by reference in paragraph (b) of this section, subject
to the conditions listed in paragraph (b) of this section.
(4) Throughout the service life of a boiling or pressurized water-
cooled nuclear power facility, pumps and valves which are classified as
ASME Code Class 1, Class 2, and Class 3 must meet the inservice test
requirements, except design and access provisions, set forth in the
ASME OM Code and addenda that become effective
[[Page 24359]]
subsequent to editions and addenda specified in paragraphs (f)(2) and
(f)(3) of this section and that are incorporated by reference in
paragraph (b) of this section, to the extent practical within the
limitations of design, geometry and materials of construction of the
components.
(i) Inservice tests to verify operational readiness of pumps and
valves, whose function is required for safety, conducted during the
initial 120-month 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 under this part, or 12 months before
the date scheduled for initial loading fuel under a combined license
under part 52 of this chapter (or the optional ASME Code cases listed
in NRC Regulatory Guide 1.192, that is incorporated by reference in
paragraph (b) of this section), subject to the conditions listed in
paragraph (b) of this section.
(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
Regulatory Guide 1.147, Revision 15, or Regulatory Guide 1.192 that are
incorporated by reference in paragraph (b) of this section), subject to
the conditions listed in paragraph (b) of this section.
(iii) [Reserved]
(iv) Inservice tests of pumps and valves may meet the requirements
set forth in subsequent editions and addenda that are incorporated by
reference in paragraph (b) of this section, subject to the conditions
listed in paragraph (b) of this section, and subject to NRC approval.
Portions of editions or addenda may be used provided that all related
requirements of the respective editions or addenda are met.
(5) * * *
(iv) Where a pump or valve test requirement by the code or addenda
is determined to be impractical by the licensee and is not included in
the revised inservice test program as permitted by paragraph (f)(4) of
this section, the basis for this determination must be submitted for
NRC review and approval not later than 12 months after the expiration
of the initial 120-month interval of operation from start of facility
commercial operation and each subsequent 120-month interval of
operation during which the test is determined to be impractical.
* * * * *
(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
III or Section XI of the ASME B&PV Code (or ASME OM Code for snubber
examination and testing) incorporated by reference in paragraph (b) of
this section (or the optional ASME code cases listed in NRC Regulatory
Guide 1.147, Revision 15, that are incorporated by reference in
paragraph (b) of this section) in effect six 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 Regulatory Guide 1.147, Revision 15, when using Section XI, or
Regulatory Guide 1.192 when using the OM Code, that are incorporated by
reference in paragraph (b) of this section), subject to the applicable
conditions.
(3) For a boiling or pressurized water-cooled nuclear power
facility whose construction permit under this part, or design
certification, design approval, combined license, or manufacturing
license under part 52 of this chapter, was issued on or after July 1,
1974:
(i) Components (including supports) which are classified as ASME
Code Class 1 must be designed and 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 III or Section XI of the ASME B&PV Code (or ASME OM
Code for snubber examination and testing) incorporated by reference in
paragraph (b) of this section (or the optional ASME code cases listed
in NRC Regulatory Guide 1.147, Revision 15, when using Section XI; or
Regulatory Guide 1.192 when using the OM Code, 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 III or Section XI of the ASME B&PV Code
(or ASME OM Code for snubber examination and testing) incorporated by
reference in paragraph (b) of this section (or the optional ASME code
cases listed in NRC Regulatory Guide 1.147, Revision 15, when using
Section XI; or Regulatory Guide 1.192 when using the OM Code, that are
incorporated by reference in paragraph (b) of this section) applied to
the construction of the particular component.
(iii)-(iv) [Reserved]
(v) All components (including supports) may meet the requirements
set forth in subsequent editions of codes and addenda or portions
thereof which are incorporated by reference in paragraph (b) of this
section, subject to the conditions listed therein.
(4) Throughout the service life of a boiling or pressurized water-
cooled nuclear power facility, components (including supports) which
are classified as ASME Code Class 1, Class 2, and Class 3 must meet the
requirements, except design and access provisions and preservice
examination requirements, set forth in Section XI of editions and
addenda of the ASME B&PV Code (or ASME OM Code for snubber examination
and testing) that become effective subsequent to editions specified in
paragraphs (g)(2) and (g)(3) of this section and that are incorporated
by reference in paragraph (b) of this section, to the extent practical
within the limitations of design, geometry and materials of
construction of the components. Components which are classified as
Class MC pressure retaining components and their integral attachments,
and components which are classified as Class CC pressure retaining
components and their integral attachments must meet the requirements,
except design and access provisions and preservice examination
requirements, set forth in Section XI of the ASME B&PV Code and addenda
that are incorporated by reference in paragraph (b) of this section,
subject to the condition listed in paragraph (b)(2)(ii) of this section
and the conditions listed in paragraphs (b)(2)(iv) and (b)(2)(v) of
this section, to the extent
[[Page 24360]]
practical within the limitation of design, geometry and materials of
construction of the components.
(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 Regulatory Guide 1.147, Revision
15, when using Section XI; or Regulatory Guide 1.192 when using the OM
Code, 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 Regulatory Guide 1.147, Revision 15, when
using Section XI; or Regulatory Guide 1.192 when using the OM Code,
that are incorporated by reference in paragraph (b) of this section),
subject to the conditions listed in paragraph (b) of this section.
(iii) When applying editions and addenda prior to the 2003 Addenda
of Section XI of the ASME B&PV Code licensees may, but are not required
to, perform the surface examinations of high-pressure safety injection
systems specified in Table IWB-2500-1, Examination Category B-J, Item
Numbers B9.20, B9.21 and B9.22.
(iv) Inservice examination of components and system pressure tests
may meet the requirements set forth in subsequent editions and addenda
that are incorporated by reference in paragraph (b) of this section,
subject to the conditions listed in paragraph (b) of this section, and
subject to Commission approval. Portions of editions or addenda may be
used provided that all related requirements of the respective editions
or addenda are met.
(v) For a boiling or pressurized water-cooled nuclear power
facility whose construction permit under this part or combined license
under part 52 of this chapter was issued after January 1, 1956:
(A) Metal containment pressure retaining components and their
integral attachments must meet the inservice inspection, repair, and
replacement requirements applicable to components which are classified
as ASME Code Class MC;
(B) Metallic shell and penetration liners which are pressure
retaining components and their integral attachments in concrete
containments must meet the inservice inspection, repair, and
replacement requirements applicable to components which are classified
as ASME Code Class MC;
(C) Concrete containment pressure retaining components and their
integral attachments, and the post-tensioning systems of concrete
containments must meet the inservice inspections, repair, and
replacement requirements applicable to components which are classified
as ASME Code Class CC.
(5) * * *
(iii) If the licensee has determined that conformance with a code
requirement is impractical for its facility, the licensee shall notify
the Commission and submit, as specified in Sec. 50.4, information to
support the determinations. Determinations of impracticality in
accordance with this section must be based on the demonstrated
limitations experienced when attempting to comply with the code
requirements during the inservice inspection interval for which the
request is being submitted. Requests for relief made in accordance with
this section must be submitted to the NRC no later than 12 months after
the examination has been attempted.
(iv) Where the licensee determines that an examination required by
Code edition or addenda is impractical, and is not included in the
revised inservice inspection program as permitted by paragraph (g)(4)
of this section, the basis for this determination must be submitted for
NRC review and approval not later than 12 months after the expiration
of the initial or subsequent 120-month inspection interval for which
relief is sought.
(6) * * *
(ii) * * *
(B) Licensees do not have to submit to the NRC for approval of
their containment inservice inspection programs which were developed to
satisfy the requirements of Subsection
IWE and Subsection IWL with specified conditions. The program
elements and the required documentation must be maintained on site for
audit.
* * * * *
(E) * * *
(1) All licensees of pressurized water reactors shall augment their
inservice inspection program by implementing ASME Code Case N-722-1
subject to the conditions specified in paragraphs (g)(6)(ii)(E)(2)
through (g)(6)(ii)(E)(4) of this section. The inspection requirements
of ASME Code Case N-722-1 do not apply to components with pressure
retaining welds fabricated with Alloy 600/82/182 materials that have
been mitigated by weld overlay or stress improvement.
(2) If a visual examination determines that leakage is occurring
from a specific item listed in Table 1 of ASME Code Case N-722-1 that
is not exempted by the ASME Code, Section XI, IWB-1220(b)(1),
additional actions must be performed to characterize the location,
orientation, and length of crack(s) in Alloy 600 nozzle wrought
material and location, orientation, and length of crack(s) in Alloy 82/
182 butt welds. Alternatively, licensees may replace the Alloy 600/82/
182 materials in all the components under the item number of the
leaking component.
(3) If the actions in paragraph (g)(6)(ii)(E)(2) of this section
determine that a flaw is circumferentially oriented and potentially a
result of primary water stress corrosion cracking, licensees shall
perform non-visual NDE inspections of components that fall under that
ASME Code Case N-722-1 item number. The number of components inspected
must equal or exceed the number of components found to be leaking under
that item number. If circumferential cracking is identified in the
sample, non-visual NDE must be performed in the remaining components
under that item number.
* * * * *
(F) Inspection requirements for class 1 pressurized-water reactor
piping and vessel nozzle butt welds.
(1) Licensees of existing operating pressurized-water reactors as
of [publication date of the final rule] shall implement the
requirements of ASME Code Case N-770, subject to the conditions
specified in paragraphs (g)(6)(ii)(F)(2) through (g)(6)(ii)(F)(16) of
this section, by the first refueling outage after [date that is 60 days
after the date of publication of the final rule].
(2) Full structural weld overlays authorized by the NRC staff may
be categorized as Inspection Items C or F, as appropriate; welds that
have been mitigated by stress improvement without welding may be
categorized as Inspection Items D or E, as appropriate, provided the
criteria in Appendix I of the code case have been met; for ISI
frequencies, all other butt welds that rely on Alloy 82/182 for
structural integrity shall be categorized as Inspection Items A-1, A-2
or B until the NRC staff has reviewed the mitigation and authorized an
alternative code case
[[Page 24361]]
Inspection Item for the mitigated weld, or until an alternative code
case Inspection Item is used based on conformance with an ASME
mitigation code case endorsed in Regulatory Guide 1.147 with
conditions, if applicable, and incorporated in this section.
(3) Welds in Table 1, Inspection Items A-1, A-2, and B, that have
not received a baseline examination using Section XI, Appendix VIII
requirements, shall be examined at the next refueling outage after [the
effective date of the final rule].
(4) The axial examination coverage requirements of -2500(c) may not
be considered to be satisfied unless essentially 100 percent coverage
is achieved.
(5) Replace paragraph--3132.3(b) with ``Previously-evaluated flaws
that were mitigated by the techniques identified in Table 1 need not be
reevaluated nor have additional successive or additional examinations
performed if new planar flaws have not been identified or previously
evaluated flaws have remained essentially unchanged.''
(6) If a weld mitigated by inlay or cladding is determined through
a volumetric examination to have cracking that penetrates beyond the
thickness of the inlay or cladding, the weld must be reclassified as
and inspected using the frequencies of Inspection Item A-1, A-2, or B,
as appropriate, until corrected by repair/replacement activity in
accordance with IWA-4000 or by corrective measures beyond the scope of
Code Case N-770.
(7) For Inspection Items G, H, J, and K, the surface examination
requirements of Table 1 must apply whether the inservice volumetric
examinations are performed from the weld outside diameter or the weld
inside diameter. All hot leg operating temperature welds in inspection
items G, H, J, and K must be inspected each interval. A 25 percent
sample of cold leg operating temperature welds must be inspected
whenever the core barrel is removed (unless it has already been
inspected within the past 10 years) or 20 years, whichever is less.
(8) The first examination following weld inlay, cladding, weld
overlay or stress improvement for Inspection Items D, G, and H may not
be deferred to the end of the interval.
(9) In applying Measurement or Quantification Criterion I-1.1 of
Appendix I, a construction weld repair from the inside diameter to a
depth of 50 percent of the weld thickness extending 360[deg] around the
weld shall be assumed.
(10) The last sentence of Measurement or Quantification Criterion
I-2.1 of Appendix I shall be replaced by, ``The analysis or
demonstration test shall account for (a) load combinations that could
relieve plastic stress due to shakedown and (b) any material properties
related to stress relaxation over time.''
(11) Replace Measurement or Quantification Criterion I-7.1 of
Appendix I, with ``An analysis shall be performed using IWB-3600
evaluation methods and acceptance criteria to verify that the
mitigation process will not cause any existing flaws to grow.
(12) For any mitigated weld whose volumetric examination detects
new flaws or growth of existing flaws in the required examination
volume that exceed the acceptance standards of IWB-3514 and are found
to be acceptable for continued service through an analytical evaluation
meeting the requirements of IWB-3600 or a repair meeting the
requirements of IWA-4000 or the alternative requirements of an ASME
code case, a report summarizing the evaluation, along with inputs,
methodologies, assumptions, and cause of the new flaw or flaw growth is
to be provided to the NRC prior to the weld being placed in service
other than modes 5 or 6.
(13) Replace the last sentence of the Extent and Frequency of
Examination for Inspection Items C and F with, ``Twenty-five percent of
this population shall be added to the ISI Program in accordance with -
2410 and shall be examined the shorter of once each inspection interval
or the life of the overlay.''
(14) In Figures 2(b) and 5(b), the dimension ``b'' must be used in
place of \1/2\ inch (13 mm), where ``b'' is equivalent to the nominal
thickness of the nozzle or pipe being overlaid, as appropriate.
(15) For Inspection Items G, H, J, and K, when applying the
acceptance standards of ASME B&PV Code, Section XI, IWB-3514, the
thickness ``t'' in IWB-3514 is the thickness of the inlay or onlay.
(16) Welds mitigated by optimized weld overlays in Inspection Items
D and E are not permitted to be placed into a population to be examined
on a sample basis and must be examined once each inspection interval.
* * * * *
\1\ For inspections to be conducted once per interval, the
inspections shall be performed in accordance with the schedule in
Section XI, paragraph IWB-2400, except for plants with inservice
inspection programs based on a Section XI edition or addenda prior
to the 1994 Addenda. For plants with inservice inspection programs
based on a Section XI edition or addenda prior to the 1994 Addenda,
the inspection shall be performed in accordance with the schedule in
Section XI, paragraph IWB-2400, of the 1994 Addenda.
* * * * *
Dated at Rockville, Maryland, this 19th day of April 2010.
For the Nuclear Regulatory Commission.
Eric J. Leeds,
Director, Office of Nuclear Reactor Regulation.
[FR Doc. 2010-9700 Filed 5-3-10; 8:45 am]
BILLING CODE 7590-01-P