ML021440050
| ML021440050 | |
| Person / Time | |
|---|---|
| Site: | Oyster Creek |
| Issue date: | 05/23/2002 |
| From: | Richard Laufer NRC/NRR/DLPM |
| To: | Kingsley O Exelon Generation Co, Exelon Nuclear |
| Tam P, NRR/DLPM, 415-1451 | |
| References | |
| TAC MB2942 | |
| Download: ML021440050 (9) | |
Text
May 23, 2002 Mr. Oliver D. Kingsley, President and Chief Nuclear Officer Exelon Nuclear Exelon Generation Company, LLC 4300 Winfield Road Warrenville, IL 60555
SUBJECT:
OYSTER CREEK NUCLEAR GENERATING STATION DAY EXTENSION OF THE THIRD INSERVICE INSPECTION INTERVAL (TAC NO. MB2942)
Dear Mr. Kingsley:
By letter dated September 13, 2001, AmerGen Energy Company, LLC, submitted Inservice Inspection Code Request No. 27 to extend the duration of the third interval for 80 components by 90 days beyond the 1-year extension already allowed by Subarticle IWA-2430(d) of the American Society of Mechanical Engineers Boiler and Pressure Vessel Code (ASME Code).
The Nuclear Regulatory Commission (NRC) staff reviewed that submittal and has delineated details of its findings in the enclosed safety evaluation. Based on its review, the NRC staff concludes that a 90-day one-time extension to the third inservice inspection (ISI) interval beyond the 12-month extension already allowed by the ASME Code provides an acceptable level of quality and safety. Therefore, pursuant to 10 CFR 50.55a(a)(3)(i), the NRC staff authorizes the proposed alternative for the third 10-year ISI interval at Oyster Creek Nuclear Generating Station.
If you have any questions, please call Mr. Peter Tam, NRC Project Manager at (301) 415-1451.
Sincerely,
/RA/
Richard J. Laufer, Chief, Section 1 Project Directorate I Division of Licensing Project Management Office of Nuclear Reactor Regulation Docket No. 50-219
Enclosure:
Safety Evaluation cc w/encl: See next page
ML021440050 OFFICE PM/PD1-1 LA/PD1-1 BC/EMCB OGC SC/PD1-1 NAME PTam SLittle TChan*
SUttal RLaufer DATE 5/13/02 5/13/02 4/17/02 5/22/02 5/23/02
SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION THIRD 10-YEAR INTERVAL INSERVICE INSPECTION PROGRAM PLAN REQUEST NO. 27, EXTENSION OF CURRENT INTERVAL AMERGEN ENERGY COMPANY, LLC OYSTER CREEK NUCLEAR GENERATING STATION DOCKET NO. 50-219
1.0 INTRODUCTION
Inservice inspection (ISI) of the American Society of Mechanical Engineers Boiler and Pressure Vessel Code (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 10 CFR 50.55a(g), except where specific relief has been granted by the Commission pursuant to 10 CFR 50.55a(g)(6)(i). 10 CFR 50.55a(a)(3) states in part that alternatives to the requirements of paragraph (g) may be used, when authorized by the 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) will meet the requirements, except the design and access provisions and the preservice examination requirements, set forth in the ASME Code,Section XI, Rules for Inservice Inspection of Nuclear Power Plant Components, to the extent practical within the limitations of design, geometry, and materials of construction of the components. The regulations require that inservice examination of components 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 Section XI of the ASME Code incorporated by reference in 10 CFR 50.55a(b) twelve months prior to the start of the 120-month interval, subject to the limitations and modifications listed therein. The ISI code of record for Oyster Creek Nuclear Generating Station (OCNGS) third 10-year ISI interval is the 1986 Edition of the ASME Code.
By letter dated September 13, 2001, AmerGen Energy Company, LLC, (the licensee),
submitted ISI Code Request No. 27 to extend the duration of the third interval by 90 days.
Enclosure 2.0 REQUEST NO. 27, 90-DAY EXTENSION OF THE THIRD INTERVAL 2.1 Code Requirements for which Relief is Requested The licensee stated that ASME Section XI, 1986 Edition, Subarticle IWA-2430(d), allows each of the inspection intervals for Program B components to be increased or decreased by as much as 1 year.
2.2 Licensees Proposed Alternative to Code The licensee proposed a one-time, 90-day extension beyond the 1-year increase of the third interval already allowed by Subarticle IWA-2430(d) of the ASME Code to accomplish examination of the 80 components listed below (table reproduced from the September 13, 2001, submittal):
ISI SCOPE FOR REFUELING OUTAGE 1R19 Classification Category Item No.
Quantity Description Class 1 B-D B3.90 B3.100 1
CRDR Nozzle to Vessel Weld ISI and NUREG-0619 B-F B5.10 4
Nozzle to Safe-ends: 1-Control Rod Drive Return; 2-Isolation Condenser: 1-Liquid Poison B-J B9.11 B9.21 B9.32 B9.40 31 Piping Welds B-G-1 B6.10 B6.21 B6.40 B6.50 20 Reactor Vessel Head Bolts B-N-1 B-N-2 B13.11 B13.20 B13.30 B13.40 Note Reactor Vessel Internal B-O B14.10 2
Weld to Control Rod Drive Housing Class 2 C-A C1.30 1
Containment Spray Heat Exchanger Flange to Shell Weld C-C C3.20 2
Integral Attachments C-F-1 C5.11 3
Welds Follow-up from 1R18 Refueling Outage Class 3 D-C D3.20 2
Integral Attachments IWF F-A F1.10 F1.20 F1.30 F1.40 14 Component Supports Note: General vessel visual inspection and core support inspection as accessible concurrent with other inspections 2.3 Licensees Basis for Relief The licensee stated that pursuant to 10 CFR 50.55a(a)(3)(i), a one-time 90-day extension to the 1-year adjustment in Subarticle IWA-2430(d) for the examination of 80 components will provide an acceptable level of quality and safety. In accordance with Subarticle IWA-2430(d), the third inspection interval has been extended 1 year to conclude October 14, 2002. Oyster Creek refueling outage 1R19 has been rescheduled to begin mid-October 2002, after being originally scheduled to begin in September 2002. This outage schedule was changed to maximize Exelon/AmerGen resources dedicated to the Peach Bottom Unit 2 and Oyster Creek refueling outages, which are also scheduled for the fall of 2002. The third inspection interval will thus expire before the completion of the refueling outage unless an extension is granted. The original refueling schedule (September 2002) would have allowed all examinations to be completed by the end of the inspection interval.
The licensee reviewed the examination history for the third interval for the components in the same examination categories and item numbers for which the extension is being sought. The licensee stated the results of the components previously tested were that all components had passed the inspections and concluded that the one-time 90-day extension of the already extended interval was of short duration for components that did not display any structural integrity concerns. The components would be in service a short period of time in the fourth interval, but the 90-day extension would not be added to the length of the fourth interval. The licensee stated that the delayed inspections would benefit from lower heat sink temperature, resulting in improved working conditions and worker effectiveness, and reduced radiation exposure.
2.4 Evaluation The licensee is seeking relief from interval extension limitation from 1 year to 15 months (90 days beyond 1 year). Subarticle IWA-2432, Inspection Program B, states the inspection intervals shall comply with the following, except as modified by Subarticle IWA-2430(d):
.... fourth inspection interval - 10 years following the third inspection interval. Subarticle IWA-2430(d) states for components inspected under Program B, each of the inspection intervals may be extended or decreased by as much as 1 year. Adjustments shall not cause successive intervals to be altered by more than 1 year from the original pattern of intervals.
The ASME Code states that the 1-year extension will not alter the successive intervals by more than 1 year from their original pattern. This aspect of the ASME Code is important for components later in service life to assure any adverse trends are discovered. In this case, the licensee has committed to maintain the duration of the fourth interval to 10 years after the 1-year extension, regardless of the 90-day 1-time extension. This commitment is in compliance with ASME Code requirements under Subarticle IWA-2430(d) and provides reasonable assurance that any adverse trends will be discovered late in the interval, without the fourth interval being inordinately extended.
In assessing the impact to plant safety, the licensee performed a review of similarly designed components that were inspected during the third interval and found that all components had passed inspections. This provides reasonable assurance that the equipment that will be expected to operate during the last 15 months of the third interval has no adverse performance trends. Finally, the staff concludes that this 90-day one-time extension is short enough to pose minimal risk that operating equipment may develop an adverse operating trend. The list of the affected components includes static items such as welds, component supports and integral attachments. Long-term failure mechanisms such as intergranular stress corrosion cracking would have been identified prior to this extension since it typically takes 8 years at full-power operation for this anomaly to expose itself while Oyster Creek is nearing its 30th year of operation. Therefore, the NRC staff concludes that the 90-day one-time extension to the third inspection interval provides an acceptable level of quality and safety.
3.0 CONCLUSION
Based on the discussion above, the NRC staff concludes that a 90-day one-time extension to the third inspection interval beyond the 12-month extension already allowed by the ASME Code provides an acceptable level of quality and safety. Therefore, pursuant to 10 CFR 50.55a(a)(3)(i), the NRC staff authorizes the proposed alternative for the third 10-year ISI interval at OCNGS.
Principal Contributor: T. K. Steingass Date: May 23, 2002
Oyster Creek Nuclear Generating Station cc:
Chief Operating Officer Exelon Generation Company, LLC 4300 Winfield Road Warrenville, IL 60555 Senior Vice President - Nuclear Services Exelon Generation Company, LLC 4300 Winfield Road Warrenville, IL 60555 Vice President - Mid-Atlantic Operations Support Exelon Generation Company, LLC 200 Exelon Way, KSA 3-N Kennett Square, PA 19348 Senior Vice President -
Mid Atlantic Regional Operating Group Exelon Generation Company, LLC 200 Exelon Way, KSA 3-N Kennett Square, PA 19348 Kevin P. Gallen, Esquire Morgan, Lewis, & Bockius LLP 1800 M Street, NW Washington, DC 20036-5869 Kent Tosch, Chief New Jersey Department of Environmental Protection Bureau of Nuclear Engineering CN 415 Trenton, NJ 08625 Vice President -
Licensing and Regulatory Affairs Exelon Generation Company, LLC 4300 Winfield Road Warrenville, IL 60555 Site Vice President Oyster Creek Nuclear Generating Station AmerGen Energy Company, LLC PO Box 388 Forked River, NJ 08731 H. J. Miller Regional Administrator, Region I U.S. Nuclear Regulatory Commission 475 Allendale Road King of Prussia, PA 19406-1415 Mayor of Lacey Township 818 West Lacey Road Forked River, NJ 08731 Senior Resident Inspector U.S. Nuclear Regulatory Commission P.O. Box 445 Forked River, NJ 08731 Director - Licensing Exelon Generation Company, LLC Correspondence Control Desk P.O. Box 160 Kennett Square, PA 19348 Oyster Creek Generating Station Plant Manager AmerGen Energy Company, LLC P.O. Box 388 Forked River, NJ 08731 Regulatory Assurance Manager Oyster Creek Nuclear Generating Station AmerGen Energy Company, LLC P.O. Box 388 Forked River, NJ 08731 Vice President, General Counsel and Secretary Exelon Generation Company, LLC 300 Exelon Way Kennett Square, PA 19348 J. Rogge, Region I U.S. Nuclear Regulatory Commission 475 Allendale Road King of Prussia, PA 19406-1415 Manager Licensing - Oyster Creek and Three Mile Island Exelon Generation Company, LLC Nuclear Group Headquarters Correspondence Control P.O. Box 160 Kennett Square, PA 19348 Correspondence Control Desk Exelon Generation Company, LLC 200 Exelon Way, KSA 1-N-1 Kennett Square, PA 19348