PLA-5724, Proposed Relief Request No. RR-27 to the Second 10-Year Inservice Inspection Program
| ML040760785 | |
| Person / Time | |
|---|---|
| Site: | Susquehanna  |
| Issue date: | 03/05/2004 |
| From: | Shriver B Susquehanna |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| PLA-5724 | |
| Download: ML040760785 (8) | |
Text
Bryce L Shriver PPL Susquehanna, LLC % ;
Senior Vice President and 769 Salem Boulevard A on
- Chief Nuclear Officer Berwick, PA 18603 4*
Tel. 570.542.3120 Fax 570.542.1504 blshriver~pplweb.corn p i l M -_
MAR 0 5 2004 U. S. Nuclear Regulatory Commission Attn: Document Control Desk Mail Station OP1-17 Washington DC 20555 SUSQUEHANNA STEAM ELECTRIC STATION PROPOSED RELIEF REQUEST NO. RR-27 TO THE SECOND 10-YEAR INSERVICE INSPECTION PROGRAM FOR SUSQUEHANNA SES UNIT 2 PLA-5724 Docket No. 50-388 In accordance with 10 CFR 50.55a(a)(3)(i), PPL Susquehanna, LLC (PPL) requests the NRC approve the use of an alternative to the American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel Code,Section XI requirements regarding examination of Class 1, Examination Categories B-F and B-J piping welds (N8A and N8B nozzles) at Susquehanna Steam Electric Station (SSES) Unit 2. provides a copy of Relief Request No. RR-27. Attachment 2 provides a copy of ASME Code Case N-663.
The proposed alternative will allow SSES Unit 2 to avoid unnecessary examinations and radiological dose, while maintaining an acceptable level of quality and safety for the examination of the affected welds. The relief request is applicable to the second 10-year inservice inspection interval for SSES Unit 2. The applicable code of record for this inspection interval is the 1989 Edition with no Addenda of the ASME Code,Section XI.
PPL requests approval of the enclosed relief request by October 1, 2004 in order to finalize the ISI examinations to be performed during the SSES Unit 2 12 'h Refueling and Inspection Outage in spring 2005. Approval of the alternative is requested for use during the second 10-year inservice inspection program, or until Code Case N-663 is published in a future version of NRC Regulatory Guide 1.147, "Inservice Inspection Code Case Acceptability - ASME Section XI, Division 1," in which case the provisions of the Code Case N-663 conditions and limitations specified in Regulatory Guide 1.147 will be followed.
Document Control Desk PLA-5724 Similar relief requests have been granted to Arkansas Nuclear 1, Grand Gulf, River Bend, and Waterford 3 plants (refer to ADAMS Accession Numbers ML030150438 and ML032390190), and requested by the Indian Point, Pilgrim and Brunswick plants (Refer to ADAMS Accession Numbers ML033490593 and ML040280347).
There are no new commitments made in this letter. If you have any questions, please contact Mr. C. T. Coddington at (610) 774-4019.
Sincerely, B.Shriver Attachments: Attachment I - Relief Request No. RR-27 for Unit 2 Attachment 2 - ASME Code Case N-663 (For Information Only)
Copy: NRC Region 1 Mr. R. Guzman, NRC Project Manager Mr. S. Hansell, Sr. Resident Inspector Mr. R. Janati DEP/BRP
ATTACHMENT 1 RELIEF REQUEST NO. RR-27 FOR UNIT 2
Attachment 1 to PLA-5724 Page 1 of 3 PPL SUSQUEHANNA, LLC SUSQUEHANNA SES UNIT 2 SECOND 10-YEAR INTERVAL RELIEF REQUEST NO. RR-27 COMPONENTS AFFECTED Component Numbers: Class 1 piping welds (NPS 4 and larger)
Examination Category: B-F and B-J [N8A and N8B nozzles]
Item Numbers: B5.10 and B9.11 APPLICABLE CODE EDITION AND ADDENDA The Code of record for the second 10-year inservice inspection interval is the American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel Code,Section XI, 1989 Edition with no Addenda.
CODE REQUIREMENTS ASME Section XI IWB-2500 requires components be examined and pressure tested as specified in Table IWB-2500-1. This table requires a sampling of piping welds (as well as other components) be subjected to various types of non-destructive examinations (NDE) (i.e., volumetric and/or surface examinations) and pressure testing (i.e., visual, VT-2).
REASON FOR REQUEST ASME Code Case N-663 provides an alternative, which provides an acceptable level of quality and safety. This alternative also reduces dose (1 rem) because required examinations would be reduced.
PROPOSED ALTERNATIVE Pursuant to 10 CFR 50.55a(a)(3)(i), PPL proposes to use ASME Code Case N-663 in its entirety as an alternative to the surface examination requirements of Table IWB-2500-1 for examination categories B-F (NPS 4 and larger) and B-I (NPS 4 and larger).
Attachment 1 to PLA-5724 Page 2 of 3 BASIS FOR PROPOSED ALTERNATIVE The subject item numbers in ASME Section XI require a volumetric and surface examination on selected piping welds to ensure that generic degradation mechanisms are not active on either the inside diameter (I.D.) or the outside diameter (O.D.). However, these welds were selected using a deterministic set of requirements that are not based upon degradation mechanisms. ASME Code Case N-663 provides an alternative to the current ASME Section XI requirements for defining the number and location of surface examinations for piping components.
The ASME Section XI Task Group on ISI Optimization, Report No. 92-01-01, Evaluation of Inservice Inspection Requirementsfor Class 1, CategoryB-J Pressure Retaining Welds in Piping, dated July 1995, concluded, with 50 units responding with a total of 9333 welds inspected, only two (2) welds (0.02%) were found to have flaws detected by Section XI surface examinations. These flaws were determined to be fabrication-induced.
In parallel with the above, several risk-informed code cases have been developed for use on piping welds (e.g., ASME Code Cases N-560, N-577, and N-578). One of the methods for risk-informed piping examination is through use of Electric Power Research Institute (EPRI) topical report TR-1 12657, Revision B-A, Revised Risk-Informned Inservice Inspection EvaluationProcedure,approved by NRC safety evaluation dated October 28, 1999. Table 4-1, Sumnnzary of Degradation-SpecificInspection Requirements and Examination Methods, of the EPRI report lists the required degradation mechanisms to be evaluated in Class 1, 2, and 3 piping. It identifies the risk-informed examination method required for each of these degradation mechanisms. The only degradation mechanism that requires a surface examination is O.D. chloride cracking. These two initiatives led ASME to investigate the value of surface examinations.
Code Case N-663 incorporated lessons learned from the risk-informed initiatives and industry examination experience into Section XI by requiring that an evaluation be conducted to identify locations, if any, where a surface examination would be of benefit from a generic piping degradation perspective. The results of this evaluation identify where O.D. degradation is most likely to occur by reviewing plant-specific programs and practices and operating experience. If the potential for degradation is identified, Code Case N-663 defines examination techniques, volumes, and frequencies. As such, implementing Code Case N-663 will identify appropriate locations for surface examination, if any, and eliminate the unnecessary examinations. Other ASME Code,Section XI examination requirements (subject to any approved relief requests) for the subject welds, including volumetric examinations and pressure testing, will continue to be performed.
Attachment 1 to PLA-5724 Page 3 of 3 Code Case N-663 was appioved by the ASME Boiler and Pressure Vessel Code Committee on September 17, 2002, but has not yet been included in the most recent listing of NRC approved code cases provided in Revision 13 of Regulatory Guide 1.147, Inservice Inspection Code Case Acceptability-ASME Section XI Division 1.
DURATION OF PROPOSED ALTERNATIVE Approval of the alternative is requested for use during the second 10-year inservice inspection program, or until Code Case N-663 is published in a future version of NRC Regulatory Guide 1.147, "Inservice Inspection Code Case Acceptability - ASME Section XI, Division 1," in which case the provisions of the Code Case N-663 conditions and limitations specified in Regulatory Guide 1.147 will be followed.
ATTACHMENT 2 ASME Code Case N-663 (For Information Only)
CASE, N-663 CASES OF ASME BOILER AND PRESSURE VESSEL CODE Approval Daite September 17, 2002 Expiration Dae:. September 17, 2005 Case N-663 Susceptibility to outside surface attack shall be deter-Alternative Requirements.for Classes I and 2 mined in accordance with Table 1.
Surface Exaininations Examination Category B-F less than NPS 4 and Section XI, Division .1 Examinption Category B-J less than NPS 4 shall'be examined in accordance with IWB-2500.-;
Inquiry:'What alternative to the surface examination n ' All areas identified as susceptible to outside surface requirements for piping welds of Examination CategoA attack shall be examined during eachinterval. The ries'B-F, B-i, C-F-I, and C-F-2 may be used?
- requirements of IWB-2411, IWB-2412,'IWC-2411, and IWC-2412, as applicable, shall be met. Acceptance Reply. It is the opinlhn of the Committee that iin.. standards shall be in accordance.with JWB-3514 or
.. lieu of the surface examination requirements for pipini IWC-3514, as applicable. The areas shall be reexamined welds of Exanmination Category' B-F (NPS 4 and larger) , in the' same' sequence, during subsequent. inspection
-B- (NPS 4 and larger), C-F-I,,-and C-F-2, surfaco intervals over. the service lifetime of the piping item,'
examinations may.be limited to areas identified by'thi to'the extent practical.
Owner as susceptible to outside surface attack.
TABLE I SUSCEPTIBILITY CRITERIA.
Mechanism . Criteria
.External chloride
- stress corrosion and
- cracking .
- operating temperature > 1500F, and 0 a piping outside surface is within five pipe diameters of a probable leak path (e.g., valve stem) and Is covered with nonmetallic Insulation that Is not In compliance with U.S..NRC Regulatory Guide 1.36 (e.g., chloride content) or equivalent requirements or
- austenitic stainless steel base metal, welds, or HAZ, and
- a piping outside surface Is exposed to wetting from a concentrated chloride-bearing environment (e.g., seawater, brackish water, brine)
Other outside surface items Identified as susceptible to outside surface attack by a plant-specific
" '.,' Initiated mechanisms
- service history review' This review should Include plant-specific processes and programs that minimize chlorides and other contaminants.
1183 PDF RELEASE SUPP. 6- NC
( Copyright 0 2003 by the American Society of Mechanical Engineers.
t No reproduction may be made of this material without written consent of ASME., J