1CAN020905, Request for Alternative from ASME Section XI, Table IWB-2500-1, Examination Category B-N-1 Requirements
| ML090480123 | |
| Person / Time | |
|---|---|
| Site: | Arkansas Nuclear  |
| Issue date: | 02/16/2009 |
| From: | David Bice Entergy Operations |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| 1CAN020905 | |
| Download: ML090480123 (6) | |
Text
1CAN020905 February 16, 2009 U.S. Nuclear Regulatory Commission Attn: Document Control Desk Washington, DC 20555
SUBJECT:
Request for Alternative from ASME Section XI Table IWB-2500-1, Examination Category B-N-1 Requirements Arkansas Nuclear One, Unit 1 Docket No. 50-313 License No. DPR-51
Dear Sir or Madam:
Pursuant to 10 CFR 50.55a(a)(3)(ii), Entergy Operations, Inc. (Entergy) hereby requests approval of a proposed alternative to the requirements of the 2001 Edition with the 2003 Addenda of ASME Section XI for Arkansas Nuclear One, Unit 1 (ANO-1). Specifically, the requirement of Examination Category B-N-1, Item B13.10 of Table IWB-2500-1 to perform a visual inspection of the accessible areas of the reactor vessel interior. Details of the request are provided in the individual attachments to this letter.
In accordance with 10 CFR 50.55a(a)(3)(ii), the proposed alternative to the referenced requirements may be approved by the NRC provided compliance with the specified requirements results in a hardship or unusual difficulty without a compensating increase in the level of quality and safety. Entergy believes the proposed alternative meets this requirement.
The relief request does not include any new commitments.
Entergy requests approval of the proposed alternative by February 1, 2010, in order to support the Spring 2010 refueling outage. Although this request is neither exigent nor emergency, your prompt review is requested.
If you have any questions or require additional information, please contact me.
Sincerely, DBB/rwc
Attachment:
Request for Alternative ANO1-ISI-013 Entergy Operations, Inc.
1448 S.R. 333 Russellville, AR 72802 Tel 479-858-4710 David B. Bice Acting Manager, Licensing Arkansas Nuclear One
1CAN020905 Page 2 of 2 cc:
Mr. Elmo E. Collins Regional Administrator U. S. Nuclear Regulatory Commission Region IV 612 E. Lamar Blvd., Suite 400 Arlington, TX 76011-4125 NRC Senior Resident Inspector Arkansas Nuclear One P. O. Box 310 London, AR 72847 U. S. Nuclear Regulatory Commission Attn: Mr. Alan B. Wang MS O-7 D1 Washington, DC 20555-0001 Mr. Bernard R. Bevill Arkansas Department of Health Radiation Control Section 4815 West Markham Street Slot #30 Little Rock, AR 72205
Attachment to 1CAN020905 Request for Alternative ANO1-ISI-013
Attachment to 1CAN020905 Page 1 of 3 REQUEST FOR RELIEF ANO1-ISI-013 I.
Code Requirement(s)
The current code of record governing inservice inspection (ISI) for Arkansas Nuclear One, Unit 1 (ANO-1), is the 2001 Edition with the 2003 Addenda. ASME Section XI, 2001 Edition with the 2003 Addenda, Article IWB-2500 requires components to be examined and tested as specified in Table IWB-2500-1. Table IWB-2500-1, Examination Category B-N-1, Interior of Reactor Vessel, (Reference 1) Item B13.10 requires a visual examination of those areas above and below the reactor core that are made accessible for examination by removal of components during normal refueling outages. This examination is required once each inspection period.
Components/Numbers:
Reactor Vessel / R-1 Code Classes:
ASME Code Class 1
References:
- 1) ASME Section XI, Division 1, 2001 Edition with 2003 Addenda, Table IWB-2500-1
- 2) Entergy Operations Inc. Letter to the NRC, CNRO-2006-00042, Request for Alternative ANO1-ISI-007 Proposed Alternative to Extend the Third 10-Year Inservice Inspection Interval for Reactor Vessel Visual Examinations, dated September 8, 2006
- 3) NRC Letter to Entergy Operations, Inc, Arkansas Nuclear One, Unit 1 - Request for Alternative No. ANO1-ISI-007 to Extend the Third 10-Year Inservice Inspection Interval for Reactor Vessel Interior Attachments and Core Support Structure Visual Examinations, (TAC No. MD1395)
Examination Category:
B-N-1 Item Number(s):
B13.10
==
Description:==
Visual Inspection of the Accessible Areas of Reactor Vessel Interior Unit / Inspection Interval Applicability:
Arkansas Nuclear One, Unit 1 / Fourth (4th) 10-year interval, 1R22 Refueling Outage
Attachment to 1CAN020905 Page 2 of 3 II. Proposed Alternative Examinations In lieu of performing the B-N-1, Item B13.10 visual examination in the twenty-second refueling outage for ANO-1 (1R22), credit will be taken for the examinations performed during the twenty-first refueling outage (1R21). This examination provides reasonable assurance of structural integrity. The Item B13.10 visual examination will not be performed during 1R22, but will be performed during the second period of the fourth interval in accordance with Examination Category B-N-1, Item B13.10. The 100% examination of the interior of the ANO-1 reactor vessel that was performed during 1R21 is more comprehensive in nature than the Item B13.10 examination.
This request for alternative is not for the requirements of Examination Category B-N-2, Items B13.50 or B13.60 or Examination Category B-N-3, Item B13.70. These examinations will be performed on the schedule provided in the ANO-1 ISI Plan.
III. Basis for Alternative ANO-1 is currently in the fourth (4th) 10-year ISI interval. This interval began on May 31, 2008. According to the current 4th 10-year ANO-1 ISI Plan, refueling outages 1R21 and 1R22 are the only two outages in the first period of this interval.
In Reference 2, Entergy Operations, Inc, (Entergy) requested an alternative to ASME Section XI, IWB-2412, the requirement to visually examine the reactor vessel interior attachments and the core support structure required by Examination Categories B-N-2 and B-N-3 once each 10-year ISI interval. These examinations are typically performed at the end of the interval during the same refueling outage as the reactor vessel examinations.
Additionally, Entergy requested a similar deferral of the period-based visual examination of the accessible locations of the reactor vessel interior per Examination Category B-N-1. These examinations are to be performed every inspection period.
Specifically, Entergy proposed to extend the ISI interval for the identified items to the end of 1R21. 1R21 was approximately 180 days beyond the current (third 10-year interval) scheduled interval plus the Code-allowed one-year extension. Reference 2 provides the NRC approval of this request.
During 1R21, not only was the Examination Category B-N-1, Item B13.10 examination performed, but the more detailed Examination Category B-N-2, Items B13.50 and B13.60 examinations and Examination Category B-N-3, Item B13.70 examinations were performed.
These examinations are of the interior attachments within and without the beltline region and the core support structure, respectively when the core barrel was removed. The results of these examinations were acceptable.
The examinations performed during 1R21 were largely in support of the last interval of the 3rd 10-year ISI interval, but were actually performed in one of the two outages in the first period of the 4th 10-year ISI. Entergy believes that repeating the visual examination of the accessible areas of the reactor vessel interior in 1R22, having just performed an inspection 18 months prior with acceptable results, provides a hardship without a compensatory increase in the level of quality and safety.
Attachment to 1CAN020905 Page 3 of 3 IV. Conclusion 10 CFR 50.55a(a)(3) states:
Proposed alternatives to the requirements of paragraphs (c), (d), (e), (f), (g) and (h) of this section or portions thereof may be used when authorized by the Director of the Office of Nuclear Reactor Regulation. The applicant shall demonstrate that:
(i) The proposed alternatives would provide an acceptable level of quality and safety, or (ii) Compliance with the specified requirements of this section would result in hardship or unusual difficulty without a compensating increase in the level of quality and safety.
As discussed in Section IV above, Entergy believes that compliance with the requirements of ASME Section XI, Examination Category B-N-1, Item B13.10 in 1R22 would result in hardship or unusual difficulty without a compensating increase in the level of quality. Entergy believes the reactor vessel interior examinations that were performed in 1R21 satisfactorily addresses the requirements of the visual examination of the accessible areas of the interior of the vessel once per period. 1R21 and 1R22 are the only two refueling outages in the first period of this interval. Therefore, Entergy requests authorization to perform the proposed alternative to the Code requirement pursuant to 10 CFR 50.55a(a)(3)(ii) for implementation during the ANO-1, 1R22 refueling outage scheduled for the Spring 2010.