ML11136A138

Fourth 10-Year Interval Inservice Inspection Program Plan Relief Request No. 4 and Third 10-Year Interval Inservice Inspection Program Plan Relief Request No. 11

ML11136A138
Person / Time
Site:	Saint Lucie
Issue date:	06/23/2011
From:	Doug Broaddus Plant Licensing Branch II
To:	Nazar M Florida Power & Light Co
orf t j
References
TAC ME5433, TAC ME5434
Download: ML11136A138 (7)

Text

UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON. D.C. 20555*0001 June 23, 2011 Mr. Mano Nazar Executive Vice President, Nuclear and Chief Nuclear Officer Florida Power and Light Company P.O. Box 14000 Juno Beach, Florida 33408-0420

SUBJECT:

ST. LUCIE UNITS 1 AND 2 - FOURTH 10-YEAR INTERVAL INSERVICE INSPECTION PROGRAM PLAN RELIEF REQUEST NO.4 AND THIRD 10-YEAR INTERVAL INSERVICE INSPECTION PROGRAM PLAN RELIEF REQUEST NO. 11 (TAC NOS. ME5433 AND ME5434)

Dear Mr. Nazar:

By letter dated December 3,2008, Florida Power and Light Company (the licensee) submitted Relief Request (RR) No.4 for St. Lucie Unit 1 and RR-11 for St. Lucie Unit 2, requesting relief from the requirements of the American Society of Mechanical Engineers Boiler and Pressure Vessel Code,Section XI related to the schedule of examinations of the reactor vessel closure head studs, nuts, and washers as specified in Table IWB-2500-1 (successive inspection intervals), Examination Category B-G-1 and IWB-2420 of ASME Section XI, 2001 Edition through 2003 Addenda (Unit 1) and 1998 Edition through 2000 Addenda (Unit 2). Pursuant to Title 10 of the Code Federal Regulations (10 CFR) Section 50.55a(a)(3)0), the licensee proposed to use the alternative to the requirement to perform the inspections mentioned above.

The U.S. Nuclear Regulatory Commission (NRC) staff has reviewed the licensee's proposed alternative and has concluded that the proposed alternative provides an acceptable level of safety and quality. Therefore, pursuant to 10 CFR 50.55a(a)(3)(i), the proposed alternative is authorized for the remainder of the fourth 1O-year inservice inspection interval at St. Lucie Unit 1, which began on February 11, 2008, and ends on February 10, 2018, and the third 1O-year inservice inspection interval at S1. Lucie Unit 2, which began on August 8, 2003, and ends on August 7,2013.

M. Nazar -2 Further details on the bases for the NRC staffs conclusions are contained in the enclosed safety evaluation. If you have any questions regarding this matter, please contact Tracy Ort at (301) 415-2788 or bye-mail at tracy.ort@nrc.gov.

Sincerely, Douglas A Broaddus, Chief Plant Licensing Branch 11-2 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket Nos. 50-335 and 50-389

Enclosure:

Safety Evaluation cc w/enclosure: Distribution via Listserv

UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555-0001 SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION ON REQUEST FOR RELIEF THE FOURTH 10-YEAR INSERVICE INSPECTION INTERVAL ST. LUCIE NUCLEAR POWER PLANT, UNIT 1AND THE THIRD 10-YEAR INSERVICE INSPECTION INTERVAL ST. LUCIE NUCLEAR POWER PLANT, UNIT 2 FLORIDA POWER AND LIGHT COMPANY, ET AL.

DOCKET NOS. 50-335 AND 50-389

1.0 INTRODUCTION

By letter dated December 3,2008, Florida Power and Light (FPL, the licensee) submitted relief requests RR-4 and RR-11 from the requirements of the American Society of Mechanical Engineers (ASME) Code,Section XI, for st. Lucie Units 1 and 2. These relief requests are related to the inspections of reactor vessel bolting for the Unit 1 fourth and Unit 2 third 10-year inservice inspection (lSI) intervals.

2.0 REGULATORY REQUIREMENTS The lSI of ASME Code Class 1, 2, and 3 components is to be performed in accordance with Section XI, of the ASME Code and applicable edition and addenda as required by Title 10 of the Code of Federal Regulations (10 CFR) Part 50.55a(g), except where specific relief has been granted by the Commission pursuant to 10 CFR 50.55a(g)(6)(i). Section 50.55a(a)(3) of 10 CFR states that alternatives to the requirements of paragraph (g) may be used, when authorized by the Nuclear Regulatory Commission (NRC), if the applicant demonstrates that (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.

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, to the extent practical within the limitations of design, geometry, and materials of construction of the components. The code of record for the Unit 1 fourth lSI interval is ASME Boiler and Pressure Vessel Code Section XI, 2001 Edition with 2003 Addenda and for the Unit 2 third lSI interval is 1998 Edition through 2000 Addenda (Unit 2).

ENCLOSURE

- 2

3.0 TECHNICAL EVALUATION

3.1 The Licensee's Relief Request Components for Which Relief is Requested Class 1 Reactor Pressure Vessel Bolting Unit 1 Exam. Item Examination Requirements Cat. No.

8-G-1 86.10 Reactor Vessel Closure Head Nuts - Visual Examination, VT-1 86.20 Reactor Vessel Closure Studs - Volumetric Examination 86.50 Reactor Vessel Closure Washers, 8ushings - Visual Examination, VT-1 Unit 2 Exam. Item I Examination Requirements Cat. No.

8-G-1 86.10 Reactor Vessel Closure Head Nuts - Visual Examination, VT-1 86.20 Reactor Vessel Closure Studs, in place - Volumetric Examination 86.30 Reactor Vessel Closure Studs, when removed - Surface or Volumetric Examination 86.50 Reactor Vessel Closure Washers, 8ushings - Visual Examination, VT-1 ASME Code Requirements ASME Section XI, Table IW8-2500-1, Category 8-G-1, "Extent and Frequency of Examination" requires successive examinations of B-G-1 bolting will be the same as for the first interval with nuts, studs, washers, and bushings allowed to be deferred to the end of the interval so that examinations of an entire set of bolting can be performed at the same time.

ASME Section XI, Table IWB-2420(a) states, "The sequence of component examinations which was established during the first inspection interval shall be repeated during each successive inspection interval, to the extent practical."

Licensee's Basis for Requesting Relief (as stated)

In 1993, during the St. Lucie Plant, Unit 1 second lSI interval and st. Lucie Plant, Unit 2 first lSI interval, FPL purchased an additional set of reactor vessel closure studs, nuts, and washers.

With the addition, FPL currently has three complete sets of reactor pressure vessel (RPV) bolting that are shared between the two units. The three sets have been identified with three

- 3 designations "A," "B," and "C" to preclude intermixing. While in storage between outages, a set is cleaned and prepared for service. During a refueling outage in a specific unit, a complete set of RPV bolting (studs, nuts, and washers) are removed and placed into storage. The set that had been in storage is then placed into service. In between outages, the set that had been in service is cleaned, visually examined and prepared for service in accordance with FPL maintenance procedures. During the next refueling outage, on the opposite unit, this same work is performed with the set of bolting that had been previously in one unit being placed into service in the other unit. This swapping of the bolting has resulted in examinations being performed in one unit now being credited for the other.

Because FPL maintains three sets of RPV bolting components that are rotated and used in two units, it is not feasible to maintain an inspection cycle that corresponds with the periodic requirements of ASME Section XI, Table IWB-2412 for each unit. Simplifying the examination schedule for the three sets of RPV studs will ensure that FPL meets the intent of ASME Section XI, which is to examine all bolting for flaws. No RPV bolting will be installed for use that has not been examined at least once during the interval.

The requirement for bolting in the first interval at Unit 1 was to examine one-third of the bolting each period. The 1983 Edition with summer 1983 Addenda, which was used for the Unit 1 second interval, and the 1980 Edition with winter 1980 Addenda, which was used for the Unit 2 first interval, of Section XI allow deferral of examinations of B-G-1 bolting. This wording shows that the examination of RPV bolting was considered to be important, but that they can all be performed at the same time. Additionally, later editions of ASME Section XI dropped the examination schedule requirement of one-third of the bolting each period.

The two st. Lucie units have lSI intervals approximately 5-years apart with the RPV bolting sets moving from one unit to the other. FPL performs the required nondestructive examination (NDE) of three complete sets of bolting instead of two.

FPL performed the required NDE of all three sets of RPV bolting during the St. Lucie Unit 1 third interval and the st. Lucie Unit 2 second interval utilizing this alternative.

Licensee's Proposed Alternative FPL will continue to perform the ASME required NDE examinations of RPV bolting between scheduled refueling outages while the bolting is being cleaned and prepared for service in the opposite unit. Examinations will continue to be performed of all three sets of bolting during the St. Lucie Plant, Unit 1 fourth interval and the St. Lucie Plant, Unit 2 third interval and will be in accordance with Code Examination Category B-G-1 requirements and applicable relief requests. The bolting will continue on a 1O-year schedule for examination.

Additionally, as part of the preparation for service process, FPL will continue to perform visual examinations of each bolting set in accordance with maintenance procedures.

3.2 NRC Staff Evaluation In 1993, the licensee purchased an additional set of RPV bolting, including closure head nuts, studs, bushings, and washers. With the purchase of this spare set, the licensee rotates the

-4 three sets of bolting components between the two units during each refueling outage allowing the licensee to perform service, including cleaning and visual examinations, on a set of these bolting components between outages.

For Examination Category, B-G-1, ASME Code,Section XI, Table IWB-2500-1, requires that Item Nos. B6.10, B6.20, B6.30, and B6.50 (Le., RPV bolting) be examined each 10-year lSI interval and that the extent and frequency of successive inspections shall be the same as the first lSI interval. ASME Code,Section XI, IWB-2420(a) requires that the sequence of component examinations which was established during the first inspection interval shall be repeated during each successive inspection interval to the extent practical. ASME Code,Section XI, Table IWB-2412-1 requires certain percentage of the components (e.g., bolting) be examined during each period of the 10-year lSI interval such that by the end of the lSI interval, all of the components would be examined. Because three sets of bolting components are rotated and used in two units, it is not feasible to maintain an inspection cycle that corresponds with the periodic requirement of Table IWB-2412-1 for each unit. The licensee performed the required NDE of all three sets of RPV bolting during the St. Lucie Unit 1 third lSI interval and Unit 2 second lSI interval. The licensee has proposed that all three sets of bolting components be examined during the Unit 1 fourth interval and Unit 2 third interval. Having a set of bolting in storage off-line allows the licensee to perform the required examinations in nonoutage condition, thereby providing more time for examination and likely reducing radiation exposure. While the proposed alternate inspection schedule for the RPV bolting does not comply with the requirements of ASME Section XI, IWB-2420(a), it does provide an acceptable level of quality and safety.

4.0 CONCLUSION

As set forth above, the NRC staff determines that the alternative to ASME Code,Section XI, IWB-2420(a) will provide 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). Therefore, the NRC staff authorizes the licensee's proposed alternative in relief request RR-4 at St. Lucie Plant, Unit 1, for the fourth 10-year lSI interval beginning on February 11, 2008, and ending on February 10, 2018; and the NRC staff authorizes the licensee's proposed alternative in relief request RR-11 at S1. Lucie Plant, Unit 2, for the third 10-year lSI interval beginning on August 8, 2003, and ending on August 7, 2013.

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 inservice inspector.

Principal contributor: Margaret T. Audrain Date: June 23, 2011

'.. ML11136A138 OFFICE LPL2-2/PM LPL2-2/LA CPNB/BC* LPL2-2/BC NAME TOrt BClayton TLupold (JTsao for) DBroaddus DATE 05/20/11 05/20/11 05/05/11 06/23/11

• by email