ML14030A592
| ML14030A592 | |
| Person / Time | |
|---|---|
| Site: | Davis Besse  |
| Issue date: | 02/10/2014 |
| From: | Travis Tate Plant Licensing Branch III |
| To: | Lieb R FirstEnergy Nuclear Operating Co |
| Eva Brown, NRR/DORL 415-2315 | |
| References | |
| L-13-076, TAC MF0751, TAC MF0753 | |
| Download: ML14030A592 (8) | |
Text
Mr. Raymond A. Lieb Site Vice President UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555-0001 February 10, 2014 FirstEnergy Nuclear Operating Company Mail Stop A-DB-3080 5501 North State, Route 2 Oak Harbor, OH 43449-9760
SUBJECT:
DAVIS-BESSE NUCLEAR POWER STATION, UNIT NO. 1 -SAFETY EVALUATION FOR RELIEF REQUESTS RR-A1 AND RR-B1 (TAC NOS. MF0751 AND MF0753) (L-13-076)
Dear Mr. Lieb:
By letter dated February 27, 2013 (Agencywide Documents Access and Management System (ADAMS) Accession No. ML13059A321 ), FirstEnergy Nuclear Operating Company, (the licensee), submitted Relief Requests RR-A 1 and RR-B1 pursuant to Section 50.55a(a)(3)(i) of Title 10 to the Code of Federal Regulations (10 CFR) for the Davis-Besse Nuclear Power Station (DBNPS), Unit No. 1. The licensee supplemented Relief Request RR-B1 in a letter dated September 25, 2013 (ADAMS Accession No. ML13269A095). Specifically, the licensee requested in RR-A 1 to use Code Case N-532-5 to Section XI of the American Society of Mechanical Engineers Boiler and Pressure Vessel Code (ASME Code), which contains revised requirements for preparation and submittal of the inservice inspection (lSI) summary report, including Forms NIS-1 and NIS-2. Relief Request RR-B1, requested the use of alternative examination requirements for Class 2 welds in Examination Categories C-F-1 and C-F-2.
The U.S. Nuclear Regulatory Commission (NRC) staff determined that the proposed alternatives described in Relief Requests RR-A 1 and RR-B1 provide an acceptable level of quality and safety for pumps listed in the above requests. Accordingly, the NRC staff concludes that the licensee has adequately addressed all of the regulatory requirements set forth in 10 CFR 50.55a(a)(3)(i) for Relief Requests RR-A 1 and RR-B1 and is in compliance with the ASME Code requirements.
Therefore, the NRC staff authorizes the proposed alternative in requests RR-A 1 and RR-B1 for the DBNPS, Unit No. 1, fourth 1 0-year lSI program interval, which began on September 21, 2013, and is currently scheduled to end on September 20, 2023.
Should you have any questions, please feel free to contact Ms. Eva Brown at (301) 415-2315.
Docket No. 50-346
Enclosure:
Safety Evaluation cc w/encl: Distribution via Listserv Sincerely, Travis L. Tate, Chief Plant Licensing 111-2 and Planning and Analysis Branch Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation
UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555-0001 SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION RELIEF REQUESTS NOS. RR-A1 AND RR-B1 FIRSTENERGY NUCLEAR OPERATING COMPANY DAVIS-BESSE NUCLEAR POWER STATION, UNIT NO.1 DOCKET NO 50-346
1.0 INTRODUCTION
By letter dated February 27, 2013 (Agencywide Documents Access and Management System (ADAMS) Accession No. ML13059A321), FirstEnergy Nuclear Operating Company, the licensee, submitted Relief Requests RR-A 1 and RR-81 pursuant to Section 50.55a(a)(3)(i) to Title 10 of the Code of Federal Regulations (1 0 CFR) for the Davis-Besse Nuclear Power Station (DBNPS), Unit No. 1. The licensee supplemented Relief Request RR-B1 in a letter dated September 25, 2013 (ADAMS Accession No. ML13269A095). Specifically, the licensee requested in RR-A1 to use Code Case N-532-5 to Section XI of the American Society of Mechanical Engineers Boiler and Pressure Vessel Code (ASME Code), which contains revised requirements for preparation and submittal of the inservice inspection (lSI) summary report, including Forms NIS-1 and NIS-2.
Relief Request RR-81, requested the use of alternative examination requirements for Class 2 welds in Examination Categories C-F-1 and C-F-2.
These reliefs were requested for the fourth 1 0-year lSI interval at DBNPS, which began on September 21, 2012, and ends on September 20, 2022.
2.0 REGULATORY EVALUATION
Pursuant to 10 CFR 50.55a(g)(4), ASME Code Class 1, 2 and 3, components, (including supports), shall meet the requirements, except the design and access provisions and the preservice examination requirements, set forth in the ASME Code,Section XI, "Rules for In service Inspection of Nuclear Power Plant Components," to the extent practical within the limitations of design, geometry, and materials of construction of components. Paragraph 50.55a(g)(4)(i) requires that inservice examination of components and system pressure tests conducted during the first 1 0-year inspection interval comply with the requirements of the latest edition and addenda of Section XI of the ASME Code incorporated by reference in 10 CFR 50.55a(b)(2) 12 months prior to the issuance of the operating license, subject to the conditions listed therein. Paragraph 50.55a(g)(4)(ii) requires that inservice examination of components and system pressure tests conducted during subsequent 1 0-year inspection intervals comply with the Enclosure requirements of the latest edition and addenda of Section XI of the ASME Code incorporated by reference in 10 CFR 50.55a(b )(2) 12 months prior to the start of the 120-month inspection interval, subject to the conditions listed therein Section 50.55a{a)(3) to1 0 CFR states that alternatives to the requirements of paragraph(g) may be used, when authorized by the U.S. Regulatory Commission (NRC or Commission), if (i) the proposed alternatives would provide an acceptable level of quality and safety or {ii) compliance with the specified requirements would result in hardship or unusual difficulty without a compensating increase in the level of quality and safety. Section 50.55a(g)(5)(iii) to 10 CFR states that if the licensee has determined that conformance with certain code requirements is impractical for its facility, the licensee shall notify the Commission and submit, as specified in 10 CFR 50.4, to support the determinations.
By letter dated September 30, 2002, (ADAMS Accession No. ML022700279), a similar request to RR-B1 was approved by NRC for the DBNPS. The precedent cited by the licensee was considered as part of this review.
3.0 TECHNICAL EVALUATION
3.1 Licensee's Alternative Request RR-A 1 3.1.1
Applicable Code Edition and Addenda
The applicable ASME Code,Section XI, edition and addenda for DBNPS is the 2007 Edition through the 2008 Addenda.
3.1.2 Components for Which Relief is Being Requested The licensee proposed alternative to the requirements for preparation and submittal of the lSI summary report, including Forms NIS-1 and NIS-2 for Code Class 1, 2, 3, and MC components.
3.1.3 Licensee's Basis and Proposed Alternative The DBNPS lSI program is based on the ASME Code,Section XI, 2007 Edition with the 2008 Addenda. This code contains the following requirements concerning the repair/replacement activity documentation requirements, lSI summary report preparation/submission requirements and use of Forms NIS-1 and NIS-2:
Paragraph IWA-4331 (d) requires Form NIS-2 to be completed for rerating, except for component supports.
Paragraph IWA-621 0 requires a summary report to be prepared for preservice and inservice examination of Class 1 and 2 components and their supports along with the appropriate Forms NIS-1 for examination and NIS-2 for repair/replacement activities.
Paragraph IWA-6230 requires an lSI summary report to be prepared following each refueling outage and provides details for preparation and content of the report.
Paragraph IWA-6240 requires the lSI summary report to be submitted within 90 calendar days of the completion of each refueling outage.
Paragraph IWA-6350 requires Form NIS-2 preparation and retention as part of the repair/replacement activities.
Mandatory Appendix XI, Article IX-1 OOO(e), requires welding performed as part of the fabrication and installation of mechanical clamping devices to be documented on Form NIS-2.
Code Case N-532-4 provides an ASME approved alternative to the ASME Section XI requirements for preparation and submittal of the lSI summary report, including Forms NIS-1 and NIS-2. ASME Code Case N-532-4 is included in Table 1 of Regulatory Guide (RG) 1.147, Revision 16. Table 1 provides a list of code cases that are acceptable to the NRC staff for implementation in the lSI of light-water cooled nuclear power plants. However, the code case is not applicable to the 2007 Edition with the 2008 Addenda of ASME Section XI. Therefore, N-532-4 does not meet the requirement contained in IWA-2441(b) which requires code cases to be applicable to the Edition and Addenda specified in the Inspection Plan.
The licensee requests the use of ASME Code Case N-532-5 as an alternative to the ASME Section XI requirements as an acceptable alternative through 10 CFR 50.55a(a)(3)(i). The licensee requested the use of N-532-5 as a proposed alternative to all cases where completion of Form NIS-1, Form NIS-2 or a preservice and/or lSI summary report is required. ASME Code Case N-532-5 was approved by ASME and published in Supplement 5 to the 2010 Edition of the Nuclear Code Case Book and its' applicability is through the 2010 Edition of the ASME Code.
Therefore, N-532-5 would meet the requirement contained in IWA-2441 (b). However, the NRC staff has not approved the use of ASME Code Case N-532-5 in RG 1.147 at this time. The licensee states that the requirements of ASME Code Case N-532-4 were not reduced; rather they were clarified and/or enhanced in ASME Code Case N-532-5.
3.1.4
NRC Staff Evaluation
Code Case N-532 was developed to provide an alternative to the repair/replacement activity documentation requirements, lSI summary report preparation and submission requirements, use of Forms NIS-1, and NIS-2. Revision 5, to the code case addresses several items:
A requirement in IWA-4331 to use Form NIS-2 when repair/replacement activities involve rerating, which is not addressed in Revision 4.
Use of the code case when utilizing other code cases which require the use of Form NIS-2, not addressed in Revision 4.
The wording in the Certificate of Inspection block on NIS-2A and OAR-1 forms is being modified to make these forms consistent with all other ASME Code Data reports.
Clarifies the timing of the completion of Form NIS-2A.
Most specific ASME Code paragraph references were deleted, which allowed Table 3 that provided cross reference to different Editions and Addenda to be deleted.
The licensee's proposed alternative would allow DBNPS to utilize ASME Code Case N-532-5 with the 2007 Edition with the 2008 Addenda of ASME,Section XI. The NRC staff reviewed changes made to ASME Code Case N-532 in developing Revision 5. This review found that there were no changes that would negatively impact the repair/replacement activity documentation requirements and lSI summary report preparation and submission requirements that are currently allowed by ASME Code Case N-532-4. Therefore, the repair/replacement activity documentation requirements and lSI summary report preparation and submission requirements of ASME Code Case N-532-5, as proposed by the licensee, are acceptable.
Based on the above, the NRC staff finds that the licensee's proposed alternative will provide an acceptable level of quality and safety.
3.1.5 RR-A 1 Conclusion As set forth above, the NRC staff concludes that the licensee's proposed alternative Relief Request RR-A 1 provides an acceptable level of quality and safety. Accordingly, the NRC staff concludes that the licensee has adequately addressed all of the regulatory requirements set forth in 10 CFR 50.55a(a)(3)(i), and is in compliance with the ASME Code's requirements. Therefore, the NRC staff authorizes use of Relief Request RR-A 1 for the fourth 1 0-year lSI interval at DBNPS which began on September 21, 2013 and is currently scheduled to end on September 20, 2023. All other ASME Code,Section XI, requirements for which relief was not specifically requested and approved in the subject request for relief remain applicable, including third-party review by the authorized Nuclear lnservice Inspector.
3.2 Licensee Alternative Relief Request RR-B1 3.2.1
Applicable Code Edition and Addenda
The applicable ASME Code,Section XI, edition and addenda for DBNPS is the 2007 Edition through the 2008 Addenda.
3.2.2 Components for Which Relief is Being Requested The licensee proposed an alternative for various Class 2, Examination Categories C-F-1 and C-F-2, piping welds on pages 5 and 6 of the proposed alternative RR-B1 in the submittal.
3.2.3 Licensee's Basis and Proposed Alternative Table IWC-2500-1, "Examination Category C-F-1 and Category C-F-2," of ASME Section XI, 2007 Edition through the 2008 Addenda require surface and volumetric examination for piping circumferential welds greater than or equal to 3/8 inch nominal thickness for piping greater than a 4-inch nominal pipe size. For high-pressure safety injection and auxiliary feedwater systems, a surface and volumetric examination is required for piping welds greater than 1/5 inch nominal wall thickness for piping greater than or equal to a 2-inch nominal pipe size and less than or equal to a 4-inch nominal pipe size.
Per Note 2 of Table IWC-2500-1, the welds selected for examination shall include 7.5 percent, but not less than 28 welds of those not exempted by paragraph IWC-1220, "Components Exempt From Examination." The note also states some welds not exempted by Paragraph IWC-1220, which do not meet the above criteria, do not require nondestructive examination (NDE), but are required to be included in the total weld count to which the 7.5 percent sampling rate is applied.
Note 2(a) requires the welds to be distributed among the Class 2 systems based on the number of welds in each system.
The licensee proposes, that in lieu of the ASME Code requirements, all welds in the containment spray (CS), decay heat (DH), high-pressure injection (HPI), or main steam systems (MSSs),
except those exempted by Paragraph IWC-1220, will be subjected to the 7.5 percent sampling rate. The welds selected for examination with wall thickness greater than 1/5 inch will receive a surface and volumetric examination. The welds selected for examination with wall thickness less than or equal to 1/5 inch will receive an augmented surface examination.
The DBNPS CS, DH, HPI, and MSSs are designed such that many portions of these systems do not require any NDE under the Table IWC-2500-1 requirements based on the nominal wall thickness of the piping. This requires the welds selected for examination in accordance with the Category C-F-1 and Category C-F-2 requirements in these systems to be concentrated in small portions of the systems and the distribution requirements of Note 2 cannot be met. Using the proposed alternative NOEs will be performed throughout the entirety of these Class 2 systems, rather than only a portion of those systems.
3.2.4
NRC Staff Evaluation
Section XI to the ASME Code does not require examination of a 4-inch nominal pipe size or greater pipe with a wall thickness less than 3/8 inch or piping between a 2-and 4-inch nominal pipe size with a wall thickness less than 1/5 inch. The licensee has proposed to apply the 7.5 percent sampling rate to all welds not exempted by Paragraph IWC-1220. The licensee's proposed alternative as described will require surface and volumetric examination of 28 welds in piping with a pipe size greater than four inches and wall thickness between 1/5 inch and 3/8 inch.
Additionally, the alternative will require surface examination of 26 welds in piping with wall thickness less than 1/5 inch. These 54 total welds in Class 2 systems important to safety would have been unavailable for selection based on the Table IWC-2500-1 requirements. The licensee's proposed alternative does not reduce the number of examinations required. It does provide a broader distribution of the examinations within these Class 2 piping systems.
Based on the above, the NRC staff has determined that the licensee's proposed alternative will allow the examinations to be performed throughout these important Class 2 systems and not limited to certain portions based on pipe wall thickness. Therefore, the NRC staff finds that the licensee's proposed alternative will provide an acceptable level of quality and safety.
3.2.5 Relief Request RR-81 Conclusion As set forth above, the NRC staff concludes that the licensee's proposed alternative Relief Request RR-81 provides an acceptable level of quality and safety. Accordingly, the NRC staff concludes that the licensee has adequately addressed all of the regulatory requirements set forth in 10 CFR 50.55a(a)(3)(i), and is in compliance with the ASME Code's requirements. Therefore, the NRC staff authorizes use of Relief Request RR-8 1 for the fourth 1 0-year lSI interval at DBNPS, which began on September 21, 2013, and is currently scheduled to end on September 20, 2023. All other ASME Code,Section XI, requirements for which relief was not specifically requested and approved in the subject request remain applicable, including third-party review by the authorized Nuclear lnservice Inspector.
Principle Contributor: K. Hoffman Date of issuance: February 10, 2014
ML47030A592 NRR-028 OFFICE LPL3-2/PM LPL3-2/LA EPNB/BC LPL3-2/BC NAME EBrown SRohrer TLupold TTate DATE 2/5/14 2/4/14 1/24/13 2/10/14