ML081690887
| ML081690887 | |
| Person / Time | |
|---|---|
| Site: | Point Beach  |
| Issue date: | 08/25/2008 |
| From: | Lois James Plant Licensing Branch III |
| To: | Meyer L Florida Power & Light Energy Point Beach |
| Cushing J 415-1424 | |
| References | |
| RR-18, RR-1950, RR-20, TAC MD6346, TAC MD6347 | |
| Download: ML081690887 (7) | |
Text
August 25, 2008 Mr. Larry Meyer Site Vice President FPL Energy Point Beach, LLC 6610 Nuclear Road Two Rivers, WI 54241
SUBJECT:
POINT BEACH NUCLEAR PLANT, UNITS 1 AND 2 - THE FOURTH 10-YEAR INTERVAL INSERVICE INSPECTION PROGRAM PLAN REQUESTS FOR RELIEF NO. RR-21 (TAC NOS. MD8319 AND MD8320)
Dear Mr. Meyer:
By letter dated March 14, 2008, the FPL Energy, LLC, (the licensee) submitted a relief request (RR-21) from certain requirements of the American Society of Mechanical Engineers (ASME)
Boiler and Pressure Vessel Code at the Point Beach Nuclear Plant, Units 1 and 2. Specifically, the licensee proposed using a root mean square error (RMS) criterion for sizing flaws that is greater than the ASME Code,Section XI, Appendix VIII, Supplement 2 and Supplement 10 acceptance criterion for examinations performed from the inside surface of pressure boundary piping. The request is for the fourth 10-year inservice inspection (ISI) interval which is scheduled to end June 30, 2012, for both units.
The U.S. Nuclear Regulatory Commission staff concluded in the enclosed safety evaluation, that compliance with the ASME Code Case N-695 required 0.125-inch RMS depth sizing error is impractical, and that the proposed alternative to use 0.212-inch RMS error for N-695 provides reasonable assurance of structural integrity of the dissimilar metal welds. Therefore, pursuant to 10 CFR 50.55a(g)(6)(i), relief is granted to Point Beach Nuclear Plant, Units 1 and 2 to implement Request RR-21 for the fourth 10-year ISI interval or until such time as ultrasonic testing techniques are capable of satisfying the 0.125-inch RMS requirement of N-695. The granting of relief is authorized by law and will not endanger life or property, or the common defense and security and is otherwise in the public interest, given the consideration of the burden upon the licensee.
All other requirements of the ASME Code,Section XI for which relief has not been specifically requested remain applicable, including third party review by the Authorized Nuclear Inservice Inspector.
Sincerely,
/RA/
Lois James, Chief Plant Licensing Branch III-1 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket Nos. 50-266 and 50-301
Enclosure:
As stated cc w/encl: See next page
L. Meyer All other requirements of the ASME Code,Section XI for which relief has not been specifically requested remain applicable, including third party review by the Authorized Nuclear Inservice Inspector.
Sincerely,
/RA/
Lois James, Chief Plant Licensing Branch III-1 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket Nos. 50-266 and 50-301
Enclosure:
As stated cc w/encl: See next page DISTRIBUTION:
PUBLIC LPL3-1 R/F RidsNrrDorlLpl3-1 RidsNRRPMJCushing RidsNrrLATHarris RidsAcrsAcnw&mMailCenter RidsOgcRp RidsRgn3MailCenter RidsNrrOd TChan, NRR DNaujock, NRR DPelton, EDO RIII RidsNrrAdes ADAMS Accession Number: ML081690887 OFFICE LPL3-1/PM LPL3-1/LA DCI/CPNB/BC OGC LPL3-1/BC NAME JCushing THarris TChan RHolmes - NLO LJames DATE 08/13 /08 08/13 /08 04/25/08 07/09/08 08/25 /08 OFFICIAL RECORD COPY
Point Beach Nuclear Plant, Units 1 and 2 cc:
Licensing Manager FPL Energy Point Beach, LLC 6610 Nuclear Road Two Rivers, WI 54241 Mr. Ken Duveneck Town Chairman Town of Two Creeks 13017 State Highway 42 Mishicot, WI 54228 Resident Inspector's Office U.S. Nuclear Regulatory Commission 6612 Nuclear Road Two Rivers, WI 54241 Chairman Public Service Commission of Wisconsin P.O. Box 7854 Madison, WI 53707-7854 Mr. J. A. Stall Executive Vice President, Nuclear and Chief Nuclear Officer FPL Group P. O. Box 14000 Juno Beach, FL 33408-0420 T. O. Jones Vice President, Nuclear Operations Mid-West Region Florida Power & Light Company P. O. Box 14000 Juno Beach, FL 33408-0420 Peter Wells Acting Vice President, Nuclear Training and Performance Improvement Florida Power & Light Company P. O. Box 14000 Juno Beach, FL 33408-0420 Mr. M. S. Ross Managing Attorney FPL Energy, LLC P. O. Box 14000 Juno Beach, FL 33408-0420 Larry Meyer Site Vice President Point Beach Nuclear Plant 6610 Nuclear Road Two Rivers, WI 54241 John Bjorseth Plant General Manager Point Beach Nuclear Plant 6610 Nuclear Road Two Rivers, WI 54241 Mark E. Warner Vice President, Nuclear Plant Support Florida Power & Light Company P. O. Box 14000 Juno Beach, FL 33408-0420 Mr. Antonio Fernandez Senior Attorney FPL Energy, LLC P. O. Box 14000 Juno Beach, FL 33408-0420 Mr. Mano Nazar Senior Vice President and Nuclear Chief Operating Officer FPL Energy, LLC P. O. Box 14000 Juno Beach, FL 33408-0420 Abdy Khanpour Vice President Engineering Support FPL Energy, LLC P. O. Box 14000 Juno Beach, FL 33408-0420 J. Kitsembel Electric Division Public Service Commission of Wisconsin P. O. Box 7854 Madison, WI 53707-7854 July 2008
SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION FOURTH 10-YEAR INTERVAL INSERVICE INSPECTION REQUEST FOR RELIEF NO. RR-21 POINT BEACH NUCLEAR PLANT, UNITS 1 AND 2 FPL ENERGY POINT BEACH, LLC DOCKET NOS. 50-266 AND 50-301
1.0 INTRODUCTION
By letter dated March 14, 2008, Agencywide Documents Access and Management System (ADAMS) Accession No. ML080770188, the FPL Energy, LLC, (the licensee) submitted relief request (RR-21) from certain requirements of the American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel Code at the Point Beach Nuclear Plant, Units 1 & 2.
Specifically, the licensee proposed using a root mean square (RMS) error criterion for sizing flaws that are greater than Code Case N-695, AQualification Requirements for Dissimilar Metal Piping Welds (N-695),@ Paragraph 3.3(c) acceptance criterion for examinations performed from the inside surface of pressure boundary piping. N-695 is referenced in Regulatory Guide (RG) 1.147, Revision 15, Inservice Inspection Code Case Acceptability, ASME Section XI, Division.
The request is for the fourth 10-year inservice inspection (ISI) interval which is scheduled to end June 30, 2012, for both units.
2.0 REGULATORY EVALUATION
In accordance with Title 10 of the Code of Federal Regulations (10 CFR) 50.55a(g)(4), ASME Code Class 1, 2, and 3 components must meet the requirements set forth in ASME Code,Section XI, ARules for Inservice Inspection of Nuclear Power Plants Components,@ to the extent practical within the limitations of design, geometry, and materials of construction of the components. The regulations require that all inservice examinations and system pressure tests conducted during the first 10-year interval, and subsequent intervals, comply with the requirements in the latest edition and addenda of ASME Code,Section XI, incorporated by reference in 10 CFR 50.55a(b) on the date 12 months prior to the start of the 10-year interval.
For Point Beach, Units 1 and 2, the code of record for the fourth 10-year ISI interval is the 1998 Edition with 2000 Addenda of Section XI of the ASME Code.
Alternatives to requirements may be authorized or relief granted by the U.S. Nuclear Regulatory Commission (NRC, Commission) pursuant to 10 CFR 50.55a(a)(3)(i), 10 CFR 50.55a(a)(3)(ii), or 10 CFR 50.55a(g)(6)(i). In proposing alternatives to ASME requirements, 10 CFR 5055a(a)(3) requires the licensee to demonstrate that: (1) the proposed alternatives provide an acceptable level of quality and safety; (2) compliance with the specified ASME requirements would result in hardship or unusual difficulty without a compensating increase in the level of quality and safety; or (3) conformance is impractical for the facility.
Pursuant to 10 CFR 50.55a(g)(4)(iv), ISI items may meet the requirements set forth in subsequent editions and addenda of the ASME Code that are incorporated by reference in 10 CFR 50.55a(b), subject to the limitations and modifications listed therein, and subject to Commission approval. Portions of editions and addenda may be used provided that related requirements of the respective editions and addenda are met.
3.0 TECHNICAL EVALUATION
FOR REQUEST RR-21 3.1 Affected Components The 12 affected dissimilar metal welds are listed in the licensees submittal.
3.2 Applicable Code For both Units 1 and 2, the fourth 10-year ISI interval code of record for ultrasonic testing (UT) examinations is the 1998 Edition with 2000 Addenda of the ASME Code,Section XI, Appendix VIII, Supplement 10, Paragraph 3.2(b) which states that the RMS error for flaw depths estimated by UT shall not exceed 0.125-inch. Code Case N-695 is a Supplement 10 alternative that is endorsed by the NRC in RG 1.147, Revision 15.
N-695, Paragraph 3.3(c), states that Examination procedures, equipment, and personnel are qualified for depth-sizing when the RMS error of the flaw depth measurements as compared to the true flaw depths, do not exceed 0.125 in.
3.3 Proposed Alternative The licensee proposed using N-695, Paragraph 3.3(c), with a 0.212-inch RMS criterion in lieu of the required 0.125-inch RMS error.
The difference between 0.212-inch RMS error and the required 0.125-inch RMS error will be added to the UT measured flaw depth for the purpose of flaw evaluation.
3.4 Licensee Basis for the Alternative The licensee is performing volumetric examinations of all reactor pressure vessel nozzle-to-piping dissimilar metal welds from the inside diameter (ID) surface during the upcoming 10-year ISI inspections. The licensee will implement the NRC-approved alternative requirements of N-695 for qualifications.
The licensee proposes using an alternative RMS error depth-sizing requirement in lieu of the 0.125-inch RMS error value stated in N-695. A licensee representative was at the Electric Power Research Institute (EPRI) [nondestructive examination] NDE Center on August 22 and 23, 2007, and confirmed with the Performance Demonstration Initiative (PDI) administrator that no vendor has successfully demonstrated compliance with the 0.125-inch RMS value for qualification tests for examinations conducted from the ID surface of a pipe.
The licensee verified through the PDI administrator that the examination vendor selected to perform the scheduled examinations at Point Beach has achieved a 0.212-inch RMS error for the Supplement 10 qualification.
3.5 Evaluation The licensee=s ISI code of record for Units 1 and 2 fourth 10-year ISI interval is the 1998 Edition with 2000 addenda. The licensee=s vendor performed the Supplement 10 alternative, N-695, performance demonstration as implemented by the EPRI-PDI program. The licensee is requesting to use N-695 demonstrated 0.212-inch RMS error in lieu of the 0.125-inch RMS error in Paragraph 3.3(c). N-695 has been endorsed in RG 1.147.
Supplement 10 and N-695 require that the maximum error for flaw depth measurements, when compared to the true flaw depth, must not exceed 0.125-inch RMS error. The nuclear power industry has been trying to qualify personnel and procedures for examinations performed from the inside pipe diameter of dissimilar metal welds since November 2002. However, to date, no personnel or procedure has achieved the required maximum 0.125-inch RMS error. The difficulties are associated with the surface roughness and pipe alignment of the field welds. As licensees perform ID UT examinations, they are taking profilometry measurements which can be used to assess the representativeness of the test specimens used to establish the vendors RMS error. At this time, achieving a 0.125-inch maximum RMS error is impractical. The licensee has stated that the vendor has achieved a 0.212-inch RMS in their N-695 performance demonstration performed from the ID surface of the pipe.
The licensee proposed adding the depth sizing difference between their demonstrated 0.212-inch RMS error and the ASME Code-required 0.125-inch RMS error to the measured flaw value of any flaws in dissimilar metal welds.
The NRC staff finds that compliance with the N-695 required 0.125-inch RMS error is impractical at this time and that adding the difference between the performance demonstrated depth sizing RMS error and the ASME Code-required depth sizing RMS error to the measured flaw value for determining acceptability according to the standards specified in ASME Section XI, IWB-3500, provides reasonable assurance of structural integrity of the dissimilar metal welds.
4.0 Conclusion Based on the above review, the NRC staff concluded that compliance with the N-695 required 0.125-inch RMS depth sizing error is impractical, and that the proposed alternative to use 0.212-inch RMS error for N-695 provides reasonable assurance of structural integrity of the dissimilar metal welds. Therefore, pursuant to 10 CFR 50.55a(g)(6)(i), relief is granted to Point Beach Nuclear Plant, Units 1 and 2 to implement Request RR-21 for the fourth 10-year ISI interval or until such time as UT techniques are capable of satisfying the 0.125-inch RMS requirement of N-695. The granting of relief is authorized by law and will not endanger life or property, or the common defense and security and is otherwise in the public interest, given the consideration of the burden upon the licensee.
All other requirements of the ASME Code,Section XI for which relief has not been specifically requested remain applicable, including third party review by the Authorized Nuclear Inservice Inspector.
Principal Contributor: Donald Naujock, NRR Date: August 25, 2008