ML23151A466

PR-050 - 52FR24015 - Codes and Standards for Nuclear Power Plants

ML23151A466
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Issue date:	06/26/1987
From:	Stello V NRC/EDO
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PR-050, 52FR24015
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ADAMS Template: SECY-067 DOCUMENT DATE: 06/26/1987 TITLE: PR-050 - 52FR24015 - CODES AND STANDARDS FOR NUCLEAR POWER PLANTS CASE

REFERENCE:

PR-050 52FR24015 KEYWORD: RULEMAKING COMMENTS Document Sensitivity: Non-sensitive - SUNSI Review Complete

PAGE 1 OF 2 STATUS OP RULEKAKING RECORD 1 OF 1 OPOSED ROLE: PR-050 OLE NAME: CODES AND STANDARDS FOR HUCLBAR POWER PLANTS PROPOSED ROLE FED REG CITE: 52FR24015 PROPOSED ROLE PUBLICATION DATE: 06/26/87 NUMBER OF COMMENTS: 0 ORIGINAL DATE FOR COMMENTS: 08/25/87 EXTENSION DATE: I I FINAL ROLE FED. REG. CITE: 53FR16051 FINAL ROLE PUBLICATION DATE: 05/05/88 NOTES ON: EDO SIGNED FINAL ROLE ON 4/13/88. PINAL ROLE PUBLISHED AT 53 FR 16 STATUS : 051. FILE LOCATED ON Pl.

OF ROLE:

PRESS PAGE DOD OR ENTER TO SEE ROLE HISTORY OR STAFF CONTACT PRESS ESC TO SEE ADDITIONAL ROLES, (E) TO EDIT OR (S) TO STOP DISPLAY PAGE 2 OF 2 HISTORY OF THE ROLE T AFFECTED: PR-050 ROLE TITLE: CODES AND STANDARDS FOR NUCLEAR POWER PLANTS PROPOSED ROLE PROPOSED RULE DATE PROPOSED RULE SECY PAPER: SRM DATE: I I SIGNED BY SECRETARY: 06/05/87 FINAL ROLE FINAL ROLE DATE FINAL ROLE SECY PAPER: SRM DATE: I I SIGNED BY SECRETARY: 04/13/88 STAFF CONTACTS ON THE RULE CONTACTl: G.C. MILLMAN MAIL STOP: NL-237 PHONE: 443-7713 CONTACT2: MAIL STOP: PHONE:

PRESS PAGEUP TO SEE STATUS OF RULEKAKING PRESS BSC TO SEE ADDITIONAL RULES, (E) TO EDIT OR (S) TO STOP DISPLAY

DOCKET NO. PR-050 (52FR24015)

In the Matter of CODES AND STANDARDS FOR NUCLEAR POWER PLANTS DATE DATE OF TITLE OR DOCKETED DOCUMENT DESCRIPTION OF DOCUMENT 04/13/88 04/13/88 FEDERAL REGISTER NOTICE - FINAL RULE

STATUS OF RULEMAKING PROPOSED RULE: PR-050 RULE NAME: CODES AND STANDARDS FOR NUCLEAR POWER PLANTS PROPOSED RULE FED REG CITE: 52FR24015 PROPOSED RULE PUBLICATION DATE: 06/26/87 NUMBER OF COMMENTS: 0 ORIGINAL DATE FOR COMMENTS: 08/25/87 EXTENSION DATE: I I FINAL RULE FED. REG. CITE: 53FR16051 FINAL RULE PUBLICATION DATE: 05/05/88 NOTES ON EDO SIGNED FINAL RULE ON 4/13/88. FINAL RULE PUBLISHED AT 53 FR 16 TATUS 051. FILE LOCATED ON Pl.

F RULE TO FIND THE STAFF CONTACT OR VIEW THE RULEMAKING HISTORY PRESS PAGE DOWN KEY HISTORY OF THE RULE PART AFFECTED: PR-050 RULE TITLE: CODES AND STANDARDS FOR NUCLEAR POWER PLANTS

. OPOSED RULE PROPOSED RULE DATE PROPOSED RULE SECY PAPER: SRM DATE: I I SIGNED BY SECRETARY: 06/05/87 FINAL RULE FINAL RULE DATE FINAL RULE SECY PAPER: SRM DATE: I I SIGNED BY SECRETARY: 04/13/88 STAFF CONTACTS ON THE RULE CONTACTl: G.C. MILLMAN MAIL STOP: NL-237 PHONE: 443-7713 CONTACT2: MAIL STOP: PHONE:

p(l-50 NUCLEAR REGL1LATORY COMMISSION 10 CFR Part 50 Codes and Standards for Nuclear Power Plants AGENCY: Nuclear Regulatory Commission.

ACTION: Final rule.

SUMMARY

The Corm,ission is amending its regulations to incorporate by reference the Winter 1984 Addenda, Summer 1985 Addenda, Winter 1985 Addenda, atlji~o Edition of Section III, Division 1, of the ~.merican Society of Mechanical Engineers Boiler and Pressure Vessel Code (ASME Code), and the WintP,t' 1983 Addenda, Su1T1T1er 1984 Addenda, Winter 1984 Addenda, Summer 1985 Addenda, Winter 1985 Addenda, and 1986 Edition of Section XI i Division 1, of the ASME Code. A limitation is placed on the use of paragraph IWB-3640 as contained in the Winter 1983 Addenda and Winter 1984 Addenda of Section XI, Division 1. This limitation requires that for certain tyres of welds, IWB-3640 when implemented shall be used as modified by the ~!inter 1985 Addenda. In addition, the existing modification pertainin9 to the inser-vice inspection of pressure retaining welds in ASME Code Class 2 piping has been revised to limit its applicability up to the 1983 Edition with addenda up through the Su1t111er 1983 Addenda. The sections of the ASME Code being incorporated by reference provide rules for the construction of light-water-cooled nuclear power plant components and specff1 requirements

for inservice inspection of those components. Adoption of these amendments would permit the use of improved methods for construction and inservice inspection of nuclear power plants.

EFFECTIVE DATE:

• The incorporation by reference of certain publications listed in the regulations fs approved by the Office of the Director of the Office of the Federal Register as of FOR FURTHER INFORMATION CONTACT: Mr. 6. C. Millman, Division of Engineer-ing, Office of Nuclear Regulatory Research, U.S. Nuclear Regulatory Commission, Washington, DC 20555, Telephone: (301) 492-3872.

SUPPLEMENTARY INFORMATION: On June 26, 1987, the Nuclear Regulatory Com-mission published in the Federal Register (52 FR 24015) a proposed amendment to its regulation, 10 CFR Part 50, *Domestic Licensing of Production and Utilization Facilities,a to update the reference to editions and addenda of the American Society of Mechanical Engineers Boiler and Pressure Vessel Code (ASME Code). This amendment :revises§ 50.55a to incorporate by reference all editions through the 1986 Edition and all addenda through the Winter 1985 Addenda that modify Division 1 rules of Section III, *Rules for the Construction of Nuclear Plant C011ponents," and, subject to certain

/

/

limitations and modifications, addenda through the Winter 1985 Addenda that modify Division 1 rules of Sections XI, "Rules for the lnservice Inspection of Nuclear Power Plant Components," of the ASHE Code. Specifically, this amendment to§ 50.55a incorporates by referenc~ the Winter 1984 Addenda, SUlllller 1985 Addenda, Winter 1985 Addenda, and 1986 Edition for Division 1 2

rules of Section III, and the ~inter 1983 Addenda, SlJlffller 1984 Addenda, Winter 1984 Addenda, Summer 1985 Addenda, Winter 1985 Addenda, and 1986 Edition for Division 1 rules of Section XI of the ASME Code. The 1986 Edition is equivalent to the 1983 Edition, as modified by the Summer 1983 Addenda, Winter 1983 Addenda, Su11111er 1984 Addenda, ~inter 1984 Addenda, Summer 1985 Addenda, and Winter 1985 Addenda. The SUtrlller 1984 Addenda and Sumner 1985 Addenda for Section XI do not include technical requirements, but are included in the reference to prevent the confusion that might occur with a lack of continuity in the addenda references.

Interested persons were invited to submit written conrnents for con-sideration in connection with the proposed amendment by August 25, 1987.

CoT!illents were received from three individuals in response to the notice of proposed rulemaking. Two of the comnenters were in favor of the pro-posed rule, and submitted suggestions for editorial clarifications. One of these COITlllenters was concerned that the manner proposed for specifying the endorsed editions and addenda in§§ 50.55a(b)(l) and {b)(2) was poten-tially confusing for this specific amendment because the latest addenda that is specified does not modify the latest edition that fs specified (i.e., the ~inter 1985 Addenda modifies the 1983 Edition). The staff agrees with the cOfflllenter and has modified paragraphs (b){l) and (b)(2) to make ft clear that the Winter 1985 Addenda applies to the 1983 Edition, and that the 1986 Edition is the latest ASHE Code update being incorporated by reference into the regulation.

The other carmenter in favor of the proposed rule believes that the pro-posed additional sentence in§ 50.55a(b)(2)(i) which specifies a limitation on the use of IWB-3640 for certain addenda should be provided for clarity 3

in a separate paragraph. The staff has considered and adopted this suggestion. In this final rule, the specified limitation is contained in a new paragraph (b)(2)(v). This corranenter also recommended a revision to Footnote 6 to clarify details regarding implementation of the code cases specified in the identified regulatory guides. It is the opinion of the staff that the rule should not be cluttered with such infonnation. There-fore, that proposed revision has not been incorporated into the final rule.

However, the staff is considering incorporating additional information directly into the regulatory guides to clarify their use.

Additionally, this COJTITlenter noted that the Winter 1983 Addenda to Section XI included significant improvements to the inservice inspection of Class 2 piping. This co1T111ent is correct. In particular, the rules specified in that addenda satisfy NRC staff concerns associated with the

- rules specified in earlier addenda for the examination of pressure retain-ing welds in ASME Code Class 2 piping, including residual heat removal systems, emergency core cooling systems, and containment heat removal systems. The staff previously addressed these concerns by specifying a modification in§ 50.55a(b){2){iv), which required that the extent of examinations for pressure retaining welds in ASME Code Class 2 piping be determined based upon specific rules in the 1974 Edition and Addenda through the Summer 1975 Addenda. Although the commenter did not make the point specifically, the proposed rule should have recognized the improve-ments in the Winter 1983 Addenda by incorporating a revision to limit the applicability of the required existing A'!Odification specified in paragraph (b)(2)(iv) to ASME Code editions and addenda up to the 1983 Edition with addenda up through the Sunvner 1983 Addenda. This final rule 4

incorporates this limitation to the use of the modification specified in paragraph (b){2)(iv).

The third corrmenter opposed the proposed amendment. That CDlmlenter believes that the NRC should not rely on industry standards, but rather should develop its own standards based upon NRC experience and data. NRC practice is to utilize national standards, such as the ASME Code, whenever possible to define acceptable ways of implementing the NRC's basic safety regulations. This is consistent with 0MB Circular No. A-119 (Revised) 1, which provides policy and administrative guidance to federal agencies regardinp participation in the development and use of voluntary standards.

Consistent with this policy, the NRC staff participates actively in the development of many national standards, including the ASME Code, to ensure that NPC experience and data is part of the infonnation base used to sup-port development of the standard. Although the NRC staff is heavily involved in the development of the ~SME Code, endorsement of the ASME Code by the NPC without exception is not an automatic action as evidenced by the existing limitations and modifications specified in§ 50.55a(b)(2) and the new limitation specified in paragraph (b)(2)(v) by this final rule.

Paragraph IWB-3640 was incorporated into the Winter 1983 Addenda of Section XI, Division l, to provide procedures and acceptance criteria for detennining the acceptability for continued service of austenitic stain-less steel piping with flaws in excess of the allowable indications spec-ified in IWB-3514.3. Concern was expressed by the NRC staff and others t~at IWB-3640, as presented initially in the Winter 1983 Addenda, did not provide an acceptable level of margin against failure for materials with 1single copies of 0MB Circular No. A-119 may be obtained from the 0MB Publications Office, 7?6 Jackson place, NW, Washington, DC, 20503, Telephone (202) 395-7332.

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low toughness, such as might occur in fluxed welds (i.e., submerged arc welds (SAW) or shielded metal arc welds (SMAW)). One concern with low toughness materials was that such materials might fail at load levels below limit load. Additionally, there was concern that secondary stresses, which were not included in the stress analysis procedures required by IWB-3640, might contribute to the failure of low toughness materials.

The ASME established a special task group to address the concerns associated with paragraph IWB-3640 as contained in the Winter 1983 Addenda. In the interim, the NRC staff required that licensees utilizing the procedures and acceptance criteria of IWB-3640, as contained in the Winter 1983 Addenda, apply additional safety factors in their analyses to be submitted to the staff to account for the above concerns. NRC staff acceptance criteria were provided in Generic Letter 84-11, "Inspections of BWR Stainless Steel Piping." 2 In the opinion of the NRC staff, the concerns associated with material toughness have been adequately addressed by the ASME Code with the modi-fication to paragraph IWB-3640 in the Winter 1985 Addenda. This adde~da provides specific acceptance criteria for SAW and SMAW type welds, and these criteria address the concerns associated with limit load and the need to incorporate secondary stresses in the evaluation.

This amendment to§ 50.55a incorporates a limitation in paragraph

{b)(2)(v) that allows for the use of paragraph IWB-3640, as contained in the Winter 1983 Addenda and Winter 1984 Addenda, for all applications 2A copy of Generic Letter 84-11 is available for inspection or copying for a fee at the NRC Public Document Ro0111 1717 H Street NW., Washington, DC.

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permitted in that paragraph except those associated with SAW and SMA~ type welds. For these welds, this amendment specifies that paragraph IWB-3640, as modified by the Winter 1985 Addenda, must be used.

Footnote 6 of§ 50.55a provides reference to the NRC Regulatory Guides that denote which ASME Code Cases have been determined to be acceptable to the NRC staff for implementation. Previously, this footnote provided reference to only Regulatory Guides 1.84 and 1.85, which denote acceptability of Section III, Division 1, Code Cases on design and fabrication, and on materials, respectively. This amendment revises Footnote 6 to incorporate a reference to Regulatory Guide 1.147, Minservice Inspection Code Case Acceptability -- ASME Section XI Division 1," which identifies the Code Cases acceptable to the NRC staff for implementation in the inservice inspection (ISi) program of light-water-cooled nuclear power plants. At present, the Implementation section of Regulatory Guide 1.147 specifies that applicants should make a specific request to the NRC to use Code Cases endorsed in the regulatory guide. The next revision of Regulatory Guide 1.147 (i.e., Revision 6) will reflect the proposed change in Footnote 6 of the regulation. It will pennit the use of Code Cases endorsed in the regulatory guide without a specific request to the NRC for approval.

In the interim, it is the intent of the NRC that Code Cases listed in Regulatory Guide 1.147 be used without specific application to the NRC.

This amendment further revises Footnote 6 to correct the referenced titles for Regulatory Guides 1.84 and 1.85.

Paragraph 50.55a(g) provides requirements for selecting the edition and addenda of Section Y.I to be complied with during the preservice inspection(§ 50.55a(g)(3), for plants whose construction pennit was issued 7

on or after July 1, 1974); the initial 10-year inspection interval

(§ 50.55a(g)(4)(i)); and successive 10-year inspection intervals

(§ 50.55a(g)(4)(i1)). Paragraph IWA-2400 of Section XI, as revised by the Winter 1983 Addenda, incorporates rules for selecting the applicable edition and addenda of Section XI during the preservice inspection (IWA-2411); the initial 10-year inspection interval (IWA-2412); and suc-cessive 10-year inspection intervals (IWA-2413).

The criteria provided in the regulations and Section XI are effec-tively the same for the preservice inspection, and the successive 10-year inspection intervals, but differ for the initial 10-year inspection interval. For the initial 10-year inspection interval, the regulations specify that 1nservice examinations of components and inservice tests shall comply with the requirements in the latest edition and addenda of the Code incorporated by reference on the date 12 months prior to the date of issuance of the operating license while Section XI provides that the inspection plan shall comply with the Edition and Addenda of Sec-tion XI that has been adopted by the regulatory authority 36 months after the date of issuance of the construction permit, or subsequent Editions and Addenda that have been adopted by the regulatory authority. In general, use of the Comnission requirements will result in the selection of a more recent edition and addenda than will use of the Section XI rules.

Satisfying the requirements of§ 50.55a(g)(4)(i) for the initial 10-year inspection interval will, in general, also satisfy the rules of Section XI.

It is the C0111TI1ss1on's intent that in all cases the existing require-ments in§ 50.55a(g) be the basis for selecting the edition and addenda of Section XI to be complied with durin~ the preservice inspection, the 10-year inspection interval, and successive 10-year inspection intervals.

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Subsection IWE, "Requirements for Class MC Components of Light-Water Cooled Power Plants," was added to Section XI, Division 1, in the Winter 1981 Addenda. However, 10 CFR § 50.55a presently incorporates only those portions of Section XI that address the ISI requirements for Class 1, 2, and 3 components and their supports. The regulation does not currently address the ISI of containments. Since this amendment is only intended to update current regulatory requirements to include the latest ASME Code edition and addenda, the requirements of Subsection IWE would not be imposed upon C011111ission licensees by this amendment. The applicability of Subsection IWE is being considered separately.

ENVIRONMENTAL IMPACT: CATEGORICAL EXCLUSION The NRC has detennined that this final rule is the type of action described in categorical exclusion 10 CFR 51.22(c)(3). Therefore, neither an environmental impact statement nor an environmental assessment has been prepared for this final rule.

REGULATORY ANALYSIS The C0111T1ission has prepared a regulatory analysis for this amendment to the regulations. The analysis examines the costs and benefits of the alternatives considered by the COfflTlission. Interested persons may examine a copy of the regulatory analysis at the NRC Public Document Room, 1717 H St.

NW., Washington, DC. Single copies of the analysis may be obtained from Mr. 6. C. Millman, Divis1on of Engineering, Office of Nuclear Regulatory Research, U.S. Nuclear Regulatory Corrmission, ~ashington, DC, 20555, Telephone (301)492-3872.

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PAPERWORK REDUCTION ACT STATEMENT This final rule amends 1nformat1on*collect1on requirements that are subject to the Paperwork Reduction Act of 1980 (44 U.S.C. 3501 et seq.).

These requirements were approved by the Office of Management and Budget,

- approval number 3150-0011.

REGULATORY FLEXIBILITY CERTIFICATION As required by the Regulatory Flexibility Act of 1980, 5 U.S.C. 605(b),

the COOJnission hereby certifies that this rule does not have a significant economic impact on a substantial number of small entities. This rule affects only the licensing and operation of nuclear power plants. The companies that own these plants do not fall within the scope of the definition of "small entities" set forth in the Regulatory Flexibility Act or the Small Business Size Standards set out in regulations issued by the Small Business

'Administration at 13 CFR Part 121.

LIST OF SUBJECTS IN 10 CFR PART 50 Antitrust, Classified infonnation, Fire protection, Incorporation by reference, Intergovernmental relations, Nuclear power plants and reactors, Penalty, Radiation protection, Reactor siting criteria, Reporting and r~cordkeeping requirements.

Pursuant to the AtOD1ic Energy Act of 1954, as amended, the Energy Reorganization Act of 1974, as amended, and 5 U.S.C. 553, the NRC is adopting the following amendments to 10 CFR Part 50.

10

PART 50 - DOMESTIC LICENSING OF PRODUCTION AND UTILIZATION FACILITIES

l. The authority c1tat1on for Part 50 reads as follows:

~UTHORITY: 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.

1244, 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).

Section 50.7 also issued under Pub. L.95-601, sec. 10, 92 Stat. 2951 (42 U.S.C. 5851). Section 50.10 also issued under secs. 101, 185, 68 Stat. 936, 955, as amended (42 U.S.C. 2131, 2235); sec. 102, Pub. L.91-190, 83 Stat. 853 (42 U.S.C. 4332). Sections 50.23, 50.35, 50.55, and 50.56 also issued under sec. 185, 68 Stat. 955 (42 U.S.C. 2235). Sec-tions 50.33a, 50.55a and Appendi~ 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). Section 50.103 also issued under sec. 108, 68 Stat. 939, as amended {42 U.S.C. 2138). Appendix Falso issued under sec. 187, 68 Stat. 955 {42 U.S.C. 2237}.

For the purposes of sec. 223, 68 Stat. 958, as amended (42 U.S.C.

2273), §§ 50.lO(a), (b), and (c), 50.44, 50.46, 50.48, 50.54, and 50.80(a}

are issued under sec. 161b, 68 Stat. 948, as amended (42 U.S.C. 2201(b));

§§ 50.lO(b) and (c), and 50.54 are issued under sec. 1611, 68 Stat. 949, 11

as ainended (42 U.S.C. 2201{1)); and§§ 50.9, 50.55(e), 50.59(b), 50.70, 50.71, 50.72, 50.73 and 50.78 are issued under sec. 1610, 68 Stat. 950, as amended (42 U.S.C. 2201(0)).

2. For§ 50.55a, paragraph (b)(l), the introductory text of para-graph (b){2), paragraph (b)(2)(1v), and Footnote 6 are revised and para-graph (b)(2){v) is added to read as follows:

§50.55a Codes and standards

{b) ***

(1) As used in this section, references to Section III of the ASME 4t Boiler and Pressure Vessel Code refer to Section III, Division 1, and include editions through the 1983 Edit;on and Addenda through the Winter 1985 Addenda, and the 1986 Edition.

{2) As used in this section, references to Section XI of the ASME Boiler and Pressure Vessel Code refer to Section XI, Division 1, and include editions through the 1983 Edit;on and Addenda through the Winter 1985 Addenda, and the 1986 Edition, subject to the following limitations and 1110d1ficat1ons:

{iv) Pressure-retaining welds ;n ASME Code Class 2 piping {applies tQ Tables IWC-2520 or IWC-2520-1, Category C-F). {A) Appropriate Code Class 2 pipe welds in Residual Heat Removal Systems, Emergency Core Cool-ing Systems and Contairvnent Heat Removal Systems, shall be examined. When 12

applying editions and addenda up to the 1983 Edition through the Sununer 1983 Addenda of Section XI of the ASME Code, the extent of examination for these systems shall be detennined by the requirements of paragraph IWC-1220, Table IWC-25?0 Category C-F and C-G, and paragraph IWC-2411 in the 1974 Edition and Addenda through the Sunmer 1975 Addenda.

(B) For a nuclear power plant whose application for a construction penr.it was docketed prior to July 1, 1978, when applying editions and addenda up to the 1983 Edition through the Sunmer 1983 Addenda of Sec-tion XI of the ASME Code, the extent of examination for Code Class 2 pipe welds may be detennined by the requirements of paragraph IWC-1220, Table IWC-2520 Category C-F and C-6 and paragraph IWC-2411 in the 1974 Edition and Addenda through the Summer 1975 Addenda of Section XI of the ASME Code or other requirements the Cooanission may adopt.

(v) Evaluation procedures and acceptance criteria for austenitic piping (applies to IWB-3640). When applying the Winter 1983 Addenda and Winter 1984 Addenda, the rules of paragraph IWB-3640 may be used for all applica-tions permitted in that paragraph, except those associated with submerged arc welds (SAW) or shielded metal arc welds (SMAW). For SAW or SMAW, use paragraph IWB-3640, as 1110dified by the Winter 1985 Addenda.

Footnotes to§ 50.55a:

6ASM~ Code cases that have been determined suitable for use by the COfTITiission staff are listed in NRC Regulatory Guide 1.84, "Design and Code Case Acceptability -- ASME Section III Division 1,* NRC Regulatory Guide 1.85, "Materials Code Case Acceptability -- ASHE Section III Division 1,N 13

and NRC Regulatory Guide 1.147, "Inservice Inspection Code Case Acceptability -- ASME Section XI Division 1." The use of other Code cases may be authorized by the Director of the Office of Nuclear Reactor Regulation upon request pursuant to§ 50.55a{a)(3).

• i.

• Dated at ........,~~,,,_;~this JJ}t!:day o f ~ / 1988.

For the Nuclear Regulatory C01T1T1iss1on.

Execu 14

p(l-50

[7~~L...I

(_Q,f/1-,)._</0/~;y 0 NUCLEAR RESL~ATORY COMMISSION 10 CFR Part 50 Codes and Standards for Nuclear,,Power Plants AGENCY: Nuclear Regulatory C011111ission.

ACTION: Final rule.

SUMMARY

The Connission is amending its regulations to incorporate by reference the Winter 1984 Addenda, Sonner 19e5 Addenda, Winter 1985 Addenda, and 1986 Edition of Section III, Division 1, of the American Society of Mechanical Engineers Boiler and Pressure Vessel Code (ASME Code), and the Winter 1983 Addenda, Sunmer 1984 Addenda, Winter 1984 Addenda, Sunrner 1985 Addenda, Winter 1985 Addenda, and 1986 Edition of Section XI, Division 1, of the ASME Code. A limitation is placed on the use of paragraph IWB-3640 as contained in the Winter 1983 Addenda and Winter 1984 Addenda of Section XI, Division 1. This limitation requires that for certain tyres of welds, IWB-3640 when implemented shall be used as modified by the ~inter 1985 Addenda. In addition, the existing IJ!Odiffcation pertainin9 to the inser-vice inspection of pressure retaining welds in ASME Code Class 2 piping has been revised to limit its applicability up to the 1983 Edition with addenda up through the Sulllller 1983 Addenda. The sections of the ASME Code being incorporated by reference provide rules for the construction of light-water-cooled nuclear power plant components~~~:;*ts S' J ,-,~

for inservice inspection of those components. Adoption of these amendmencs would pennft the use of improved methods for construction and inservice inspection of nuclear power plants.

EFFECTIVE DATE:

• The incorporation by reference of certain publications listed in the regulations is approved by the Office of the Director of the Office of the Federal Register as of FOR FURTHER INFORMATION CONTACT: Mr. G. C. Millman, Division of Engineer-ing, Office of Nuclear Regulatory Research, U.S. Nuclear Regulatory C01111liss1on, Washington, DC 20555, Telephone: (301) 492-3872.

SUPPLEMENTARY INFORMATION: On June 26, 1987, the Nuclear Regulatory Com-mission published fn the Federal Register (52 FR 24015) a proposed amendment to its regulation, 10 CFR Part 50, "Domestic Licensing of Production and Utilization Facilities,* to update the reference to editions and addenda of the American Society of Mechanical Engineers Boiler and Pressure Vessel Code (ASME Code). Thfs amendment revises§ 50.55a to incorporate by reference all editions through the 1986 Edition and all addenda through the Winter 1985 Addenda that modify Dfvfsfon 1 rules of Section III, "Rules for the Construction of Nuclear Plant COD1ponents,* and, subject to certain limitations and 110difications, addenda through the Winter 1985 Addenda that modify Division 1 rules of Sections XI, 9 Ru1es for the Inservice Inspection of Nuclear Power Plant Components," of the ASME Code. Specifically, this amendment to§ 50.55a incorporates by reference the Winter 1984 Addenda, Swrmer 1985 Addenda, Winter 1985 Addenda, and 1986 Edition for Division 1 2

rules of Section III, and the Winter 1983 Addenda, Sunner 19f4 Addenda, Winter 1984 Addenda, Sulllmer 1985 Addenda, Winter 1985 Addenda, and 1986 Edition for Division 1 rules of Section XI of the ASME Code. The 1986 Edition is equivalent to the 1983 Edition, as modified by the SU11111er 1983 Addenda, Winter 1983 Addenda, SURlller 1984 Addenda, ~inter 1984 Addenda, Summer 1985 Addenda, and Winter 1985 Addenda. The SUlllller 1984 Addenda and Suamer 1985 Addenda for Section XI do not include technical requirements, but are included in the reference to prevent the confusion that might occur with a lack of continuity in the addenda references.

Interested persons were invited to submit written conments for con-sideration in connection with the proposed amendment by August 25, 1987.

Conr,,ents were received frmn three individuals in response to the notice of proposed rulemakfng. Two of the conmenters were tn favor of the pro-posed rule, and submitted suggestions for editorial clarifications. One of these connenters was concerned that the manner proposed for specifying the endorsed editions and addenda fn §§ 50.55a{b)(l} and (b)(2) was poten-tially confusing for this specific amendment because the latest addenda that 1s specified does not modffy the latest edition that is specified

{i.e., the ~inter 1985 Addenda modiffes the 1983 Edition). The staff agrees with the conRenter and has modified paragraphs (b){l) and (b)(2) to 11ake it clear that the Winter 1985 Addenda applies to the 1983 Edition, and that the 1986 Edition is the latest ASME Code update being incorporated by reference into the regulation.

The other canmenter in favor of the proposed rule believes that the pro-posed addftfonal sentence in§ 50.55a(b)(2)(1) which specfffes a 11mftatfon on the use of IWB-3640 for certain addenda should be provided fQr clarity 3

1n a separate paragraph. The staff has considered Jnd adopted this suggestion. In this final rule, the specified limitation is contained in a new paragraph (b)(2)(v). This corrmenter also rec01T111ended a revision to Footnote 6 to clarify details regarding implementation of the code cases specified in the identified regulatory guides. It is the opinion of the staff that the rule should not be cluttered with such infonnation. There-fore, that proposed revision has not been incorporated into the final rule.

However, the staff is considering incorporating additional information directly into the regulatory guides to clarify their use.

Additionally, this co11111enter noted that the Winter 1983 Addenda to Section XI included significant improvements to the inservice inspection of Class 2 piping. This coument is correct. In particular, the rules specified in that addenda satisfy NRC staff concerns associated with the rules specified in earlier addenda for the examination of pressure retain-ing welds in ASME Code Class 2 piping, including residual heat removal systems, emergency core cooling systems, and containment heat removal systems. The staff previously addressed these concerns by specifying a 110dification in§ 50.55a(b)(2)(iv), which required that the extent of examinations for pressure retaining welds in ASME Code Class 2 piping be determined based upon specific rules in the 1974 Edition and Addenda through the Sumner 1975 Addenda. Although the comnenter did not make the point specifically, the proposed rule should have recognized the ianprove-ments in the Winter 1983 Addenda by incorporating a revision to limit the applicability of the required existing modification specified in paragraph (b)(2)(iv) to ASME Code editions and addenda up to the 1983 Edition with addenda up through the Sunwner 1983 Addenda. This final rule 4

incorporates this limitation to the u~e of the modification specified in paragraph {b)(2)(iv).

The third corrmenter opposed the proposed amendment. That comnenter believes that the NRC should not rely on industry standards, but rather should develop its own standards based upon NRC experience and data. NRC practice is to utilize national standards, such as the ASME Code, whenever possible to define acceptable ways of implementing the NRC's basic safety regulations. This is consistent with 0MB Circular No. A-119 (Revised) 1, which provides policy and administrative guidance to federal agencies regarclinp participation in the development and use of voluntary standards.

Consistent with this policy, the NRC staff participates actively in the development of many national standards, including the ASME Code, to ensure that NPC experience and data is part of the information base used to sup-port development of the standard. Although the NRC staff is heavily J

involved in the development of the ~SME Code, endorsement of the ASME Code by the NP.C without exception is not an aut0111atic action as evidenced by the existing limitations and modifications specified in§ 50.55a(b){2) and the new limitation specified in paragraph (b)(2)(v) by this final rule.

Paragraph IWB-3640 was incorporated into the Winter 1983 Addenda of Section XI, Division l, to provide procedures and acceptance criteria for detenaining the acceptability for continued service of austenitic stain-less steel piping with flaws in excess of the allowable indications spec-ified in IWB-3514.3. Concern was expressed by the NRC staff and others t~at IWB-3640, as presented initially in the Minter 1983 Addenda, did not provide an acceptable level of 11argin against failure for materials with 1single copies of 0MB Circular No. A-119 may be obtained from the 0MB Publications Office, 7?6 Jackson place, NW, Washington, DC, 20503, Telephone (202) 395-7332.

5

low toughness, such as mi~ht occur in fluxed welds (i.e., submerged arc welds (SAW) or shielded metal arc welds (SMAW)). One concern with low toughness materials was that such materials might fail at load levels below limit load. Additionally, there was concern that secondary stresses, which were not included in the stress analysis procedures required by IWB-3640, might contribute to the failur@ of low toughness materials.

The ASME established a special task group to address the concerns associated with paragraph IWB-3640 as contained in the Winter 1983 Addenda. In the interim, the NRC staff required that licensees utilizing the procedures and acceptance criteria of IWB-3640, as contained in the Winter 1983 Addenda, apply additional safety factors in their analyses to be submitted to the staff to account for the above concerns. NRC staff acceptance criteria \olere provided in Generic Letter 84-11, *inspections of BWR Stainless Steel Piping.* 2 In the opinion of the NRC staff, the concerns associated with material toughness have been adequately addressed by the ASME Code with the 1110di-ficat1on to paragraph IWB-3640 in the Winter 1985 Addenda. This addenda provides specific acceptance criteria for SAW and SHAW type welds, and these criteria address the concerns associated with limit load and the need to incorporate secondary stresses in the evaluation.

This amendment to§ 50.55a incorporates a limitation in paragraph (b)(2)(v) that allows for the use of paragraph JWB-3640, as contained in the Winter 1983 Addenda and Winter 1984 Addenda, for all applications 2A copy of Generic letter 84-11 is available for inspection or copying for a fee at the NRC Public Document Room 1717 H Street NW., Washington, DC.

6

permitted in that paragraph except those associated with SAW and SMA~ type welds. For these welds, this amendment specifies that paragraph IWB-3640, as modified by the Winter 1985 Addenda, must be used.

Footnote 6 of§ 50.55a provides reference to the NRC Regulatory Guides that denote which ASME Code Cases have been determined to be acceptable to the NRC staff for implementation. Previously, this footnote provided reference to only Regulatory Gui<!es 1.84 and 1.85, which denote acceptability of Section III, Division 1, Code Cases on design and fabrication, and on materials, respectively. This amendment revises Footnote 6 to incorporate a reference to Regulatory Guide 1.147, uinservice Inspection Code Case Acceptability -- ASME Section XI Division 1,* which identifies the Code Cases acceptable to the NRC staff for illl)lenentation in the inservice inspection (ISI) program of light-water-cooled nuclear power plants. At e present, the Implementation section of Regulatory Guide 1.147 specifies that applicants should make a specific request to the NRC to use Code Cases endorsed in the regulatory guide. The next revision of Regulatory Guide 1.147 (i.e., Revision 6) will reflect the proposed change in Footnote 6 of the regulation. It wfll permit the use of Code Cases endorsed in the regulatory guide without a specific request to the NRC for approval.

In the interim, ft is the intent of the NRC that Code Cases listed in Regulatory Guide 1.147 be used without specific application to the NRC.

Thfs amendment further revises Footnote 6 to correct the referenced titles for Regulatory Guides 1.84 and 1.85.

Paragraph 50.55a(g) provides requirements for selecting the edition and addenda of Section Y.I to be COG'lplfed with during the preservice inspection(§ 50.55a(g)(3), for plants whose construction permit was issued 7

on or after July 1, 1974); the initial 10-year inspection interval

(§ 50.55a(g)(4)(i)); and successive 10-year inspection intervals

(§ 50.55a(g)(4}(ii)). Paragraph IWA-2400 of Section XI, as revised by the Winter 1983 Addenda, incorporates rules for selecting the applicable edition and addenda of Section XI during the preservice inspection (IWA-2411); the initial IO-year inspection interval (IWA-2412); and suc-cessive 10-year inspection intervals (IWA-2413).

The criteria provided in the regulations and Section XI are effec-tively the same for the preservice inspection, and the successive 10-year inspection intervals, but differ for the initial 10-year inspection interval. For the initial 10-year inspection interval, the regulations specify that inservice examinations of components and inservice tests shall comply with the requirements in the latest edition and addenda of the Code incorporated by reference on the date 12 months prior to the date of issuance of the operating license while Section XI provides that the inspection plan shall comply with the Edition and Addenda of Sec-tion XI that has been adopted by the regulatory authority 36 110nths after the date of issuance of the construction permit, or subsequent Editions and Addenda that have been adopted by the regulatory authority. In general, use of the COR111ission requirements will result in the selection of a more recent edition and addenda than will use of the Section XI rules.

Satisfying the requirements of§ 50.55a(g)(4)(i) for the initial 10-year inspection interval will, in general, also satisfy the rules of Section XI.

It is the C011111ission's intent that in all cases the existing require-ments in§ 50.55a(g) be the basis for selecting the edition and addenda of Section XI to be complied with durin9 the preservice inspection, the 10-year inspection interval, and successive 10-year inspection intervals.

8

(

Subsection IWE, aRequirements for Class MC Components of Light-Water Cooled Power Plants,* was added to Section XI, Division 1, in the Winter 1981 Addenda. However, 10 CFR § 50.55a presently incorporates only those portions of Section XI that address the ISi requirements for Class 1, 2, and 3 components and their supports. The regulation does not currently address the ISI of containments. Since this amendment is only intended to update current regulatory requirements to include the latest ASME Code edition and addenda, the requirements of Subsection IWE would not be imposed upon C011111ission licensees by this amendment. The applicability of Subsection IWE is being considered separately.

ENVIRONMENTAL IMPACT: CATEGORICAL EXCLUSION The NRC has determined that this final rule is the type of action described in categorical exclusion 10 CFR 51.22(c)(3). Therefore, neither an environmental 111J)act statenent nor an environmental assessment has been prepared for this final rule.

REGULATORY ANALYSIS The Connission has prepared a regulatory analysis for this amendment to the regulations. The analysis examines the costs and benefits of the alternatives considered by the C01111ission. Interested persons may examine a copy of the regulatory analysis at the NRC Public Document Ro0111, 1717 H St.

NW., Washington, DC. Single copies of the analysis may be obtained from Mr. 6. C. Millman, Division of Engineering, Office of Nuclear Regulatory Research, U.S. Nuclear Regulatory C01'1111iss1on, Washington, DC, 20555, Telephone (301)492-3872.

9

PAPERWORK REDUCTION ACT STATEMENT This final rule U1ends information*collection requirements that are subject to the Paperwork Reduction Act of 1980 (44 U.S.C. 3501 et seq.).

These requirements were approved by the Office of Management and Budget.

4t approval nwnber 3150-0011.

REGULATORY FLEXIBILITY CFRTIFJCATION As required by the Regulatory Flexibility Act of 1980, 5 U.S.C. 605(b),

the C011111ission hereby certifies that this rule does not have a significant economic impact on a substantial number of small entities. This rule affects only the licensing and operation of nuclear power plants. The companies that own these plants do not fall within t~e scope of the definition of "small entities" set forth in the Regulatory Flex1bi11ty Act or the Small Business Size Standards set out in regulations issued by the Small Business Administration at 13 CFR Part 121.

LIST OF SUBJECTS IN 10 CFR PART SO Antitrust, Classified infonnation, Fire protection, Incorporation by reference, Intergovernmental relations, Nuclear power plants and reactors, Penalty, Radiation protection, Reactor siting criteria, Reporting and

~cordkeeping requirements.

Pursuant to the Atomic Energy Act of 1954, as amended, the Energy Reorganization Act of 1974, as amended, and 5 u.s.c. 553, the NRC is adopting the following amendments to 10 CFR Part 50.

10

PART 50 - DOMESTIC LICENSING OF PRODUCTION AND UTILIZATION FACILITIES

l. The authority citation for Part 50 reads as follows:

~UTHORITY: Secs. 102, 103, 104, 105, 161, 182, 183, 186, 189, 68 Stat.

e 936, 937, 938, 948, 953, 954, 955, 956, as amended, sec. 234, 83 Stat.

1244, 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).

Section 50.7 also issued under Pub. L.95-601, sec. 10, 92 Stat. 2951 (42 U.S.C. 5851). Section 50.10 also issued under secs. 101, 185, 68 Stat. 936, 955, as amended (42 U.S.C. 2131, 2235}; sec. 102, Pub. L.91-190, 83 Stat. 853 (42 U.S.C. 4332). Sections 50.23, 50.35, 50.55, and 50.56 also issued under sec. 185, 68 Stat. 955 (42 U.S.C. 2235). Sec-tions 50.33a, 50.55a and Appendi~ 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). Section 50.103 also issued under sec. 108, 68 Stat. 939, as amended (42 U.S.C. 2138). Appendix Falso issued under sec. 187, 68 Stat. 955 (42 U.S.C. 2237).

For the purposes of sec. 223, 68 Stat. 958, as mnended (42 U.S.C.

2273), §§ 50.lO(a), (b), and (c), 50.44, 50.46, 50.48, 50.54, and 50.SO(a) are issued under sec. 161b, 68 Stat. 948, as amended (42 U.S.C. 2201(b));

§§ 50.lO(b) and (c), and 50.54 are issued under sec. 1611, 68 Stat. 949, 11 °

as amended (42 u.s.c. 2201(1)); and§§ 50.9, 50.55(e), 50.59(b), 50.70, 50.71, 50.72, 50.73 and 50.78 are issued under sec. 1610, 68 Stat. 950, as amended (42 U.S.C. 2201(0)).

2. For§ 50.55a, paragraph (b)(l), the introductory text of para-graph (b)(2), paragraph (b)(2)(1v), and Footnote 6 are revised and para-graph (b)(2)(v) is added to read as follows:

§50.55a Codes and standards (b) ***

(1) As used in this section, references to Section III of the ASME Boiler and Pressure Vessel Code refer to Section Ill, Division 1, and include editions throu~h the 1983 Edition and Addenda through the Winter 1985 Addenda, and the 1986 Edition.

(2) As used 1n this section, references to Section XI of the ASME Boiler and Pressure Vessel Code refer to Section XI, Division 1, and include editions through the 1983 Edition and Addenda through the Winter 1985 Addenda, and the 1986 Edition, subject to the following limitations and 110d1fications:

(1v) Pressure-reta1n1ng welds in ASME Code Class 2 p1p1ng (applies tQ Tables IWC-2520 or IWC-2520-1, Category C-F). (A) Appropriate Code Class 2 pipe welds in Residual Heat Removal Systems, Emergency Core Cool-ing Systems and Containment Heat Removal Systems, shall be examined. When 12

applying editions and addenda up to the 1983 Edition through the Sunner 1983 Addenda of Section XI of the ASME Code, the extent of examination for these systems shall be detennined by the requirements of paragraph IWC-1220, Table IWC-25?0 Category C-F and C-6, and paragraph IWC-2411 in the 1974 Edition and Addenda through the Sumner 1975 Addenda.

(B) For a nuclear power plant whose application for a construction permit was docketed prior to July 1, 1978, when applying editions and addenda up to the 1983 Edition through the Surrmer 1983 Addenda of Sec-tion XI of the ASHE Code, the extent of examination for Code Class 2 pipe welds may be deter11ined by the requirements of paragraph IWC-1220, Table IWC-2520 Category C-F and C-6 and paragraph IWC-2111 in the 1974 Edition and Addenda through the Sumner 1975 Addenda of Section XI of the ASME Code or other requirements the Conmission 11ay adopt.

(v) Evaluation procedures and acceptance criteria for austenitic piping (applies to IWB-3640). When applying the Winter 1983 Addenda and Winter 1984 Addenda, the rules of paragraph IWB-3640 may be used for all applica-tions pennitted in that paragraph, except those associated with submerged arc welds (SAW) or shielded metal arc welds (SMAW). For SAW or SMAW, use paragraph IWB-3640, as 1110dified by the Winter 1985 Addenda.

Footnotes to§ 50.55a:

6ASME Code cases that have been deternifned suitable for use by the Comnfsston staff are ltsted in NRC Regulatory Gutde 1.84, "Design and Code Case Acceptability -- ASME Section III Division 1,n NRC Regulatory Guide 1.85, *Materials Code Case Acceptability -- ASME Section III Division 1,*

13

and NRC Regulatory Guide 1.147, "Inservfce Inspection Code Case Acceptability -- ASME*Section XI Division 1. 11 The use of other Code cases may be authorized by the Director of the Office of Nuclear Reactor Regulation upon request pursuant to§ 50.55a{a)(3}.

• ./ *

• Dated at c::::!;;~~~:_this ,E!/!:_,J,.y o f ~ / 1988.

For the Nuclear Regulatory COR111ission.

Execu 14