ML070740518
| ML070740518 | |
| Person / Time | |
|---|---|
| Site: | Waterford  |
| Issue date: | 03/08/2007 |
| From: | Burford F G Entergy Operations |
| To: | Document Control Desk, NRC/NRR/ADRO |
| References | |
| CNRO-2007-00011 | |
| Download: ML070740518 (7) | |
Text
tergy Entergy Operations, Inc.1340 Echelon Parkway Jadcson, Mississippi 39213-8298 Tel 601-368-5755 F. G. Burford Acting Director Nuclear Safety & Ucensing CNRO-2007-00011 March 8, 2007 U. S. Nuclear Regulatory Commission Attn.: Document Control Desk Washington, DC 20555-0001
SUBJECT:
Request for Alternative W3-4SI-002 Request to Extend the Current ASME Inservice Inspection Interval in accordance with NRC Informaton Notice 98-44 Waterford Steam Electric Station, Unit 3 Docket No. 50-382 License No. NPF-38
REFERENCE:
NRC letter, Grand Gulf Nuclear Station, Unit 1 -Request for Alternative GG-ISI-003 RE: Extending the Current Inservice Inspection interval In accordance with U. S. Nuclear Regulatory Commission Information Notice 98-44 (TAC No. MD3167), dated February 13, 2007
Dear Sir or Madam:
Pursuant to 10 CFR 50.55a(a)(3)(i), Entergy Operations, Inc. (Entergy) requests approval to extend the second Inservice Inspection (ISI) interval for piping at Waterford Steam Electric Station, Unit 3 (Waterford
- 3) to the end of its sixteenth refueling outage (RFo16), currently scheduled for the fall 2009. This request is enclosed as Request for Alternative W3-lSI-002.
The requested extension is approximately seventeen months beyond the one-year extension allowed by ASME Section XAIWB-2412(b).
NRC approved a similar request for Grand Gulf Nuclear Station (GGNS) via the referenced letter. Request for Alternative W3-4S-002 contains Information pertaining to Waterford 3 that addresses the request for additional Information for the GGNS submittal.
A4c/
CNRO-2007-00011 Page 2 of 2 Entergy requests that the NRC approve W3-ISI-002 by April 1, 2008. Should you have any questions regarding this submittal, please contact Guy Davant at (601) 368-5756.This letter contains no commitme'nts.
Very truly yours, FGB/GHD/ghd
Enclosure:
Request for Alternative W3-ISI-002 cc: Mr. W. A. Eaton (ECH)Mr. J. S. Forbes (ECH)Mr. K. T. Walsh (W3)Dr. Bruce S. Mallett U. S. Nuclear Regulatory Commission Region IV 611 Ryan Plaza Drive, Suite 400 Arlington, TX 76011 U. S. Nuclear Regulatory Commission Attn: Mr. M. B. Fields MS O-7D1 Washington, DC 20555-0001 NRC Senior Resident Inspector Waterford Steam Electric Station, Unit 3 P. 0. Box 822 Killona, LA 70066 ENCLOSURE CNRO-2007-00011 REQUEST FOR ALTERNATIVE W3-ISI-002 ENTERGY OPERATIONS, INC.WATERFORD STEAM ELECTRIC STATION, UNIT 3 REQUEST FOR ALTERNATIVE W3-ISI-002 Components/N umbers: Piping Welds Code Class:
References:
1 and 2 1. ASME Section XI, 1992 Edition 2. NRC Information Notice 98-44, Ten-Year Inservice Inspection Program Update for Licensees that Intend to Implement RI-ISI of Piping 3. EPRI Technical Report MRP-1 39, Materials Reliability Program: Primary System Piping Butt Weld Inspection and Evaluation Guidelines (MRP- 139)Examination Category: Item Numbers:
Description:
Unit / Inspection Interval Applicability:
B-J, B-F, C-F-i, and C-F-2 All Piping Welds Waterford Steam Electric Station, Unit 3 (Waterford 3)!Second (2 nd) 10-year interval 1. CODE REQUIREMENT(S)
The ISI code of record for Waterford 3 is ASME Section XI 1992 Edition with portions of the 1993 Addenda applicable to pressure testing [see the NRC's safety evaluation report dated December 12, 1996 (TAC No. M94488)].ASME Section Xl Table IWB-2412-1 defines an inservice inspection (ISI) interval to be 10 years in duration.
IWB-2412(b) allows extending the interval for one year to coincide with a plant outage.I1. REQUESTED ALTERNATIVE Pursuant to 10 CFR 50.55a(a)(3)(i), Entergy Operations, Inc. (Entergy) requests authorization to extend the current ISI interval to include an additional refueling outage, which will be the sixteenth refueling outage (RF-16) currently scheduled for the fall 2009 for items in Examination Categories B-F, B-J, C-F-i, and C-F-2. This alternative will not affect the third interval start date.Page 1 of 4 III. BASIS FOR RELIEF NRC Information Notice (IN) 98-44, Ten-Year Inservice Inspection Program Update for Licensees that Intend to Implement RI-ISI of Piping (Reference 2), states that the probabilistic risk assessment technology in NRC regulatory activities should be increased to the extent supported by state-of-the-art methods and data and in a manner that complements the NRC's deterministic approach.
Basically, this information combined with risk assessment techniques and associated data provides for developing an effective approach to the ISI program. This approach provides an acceptable level of quality and safety, as required by 10 CFR 50. 55a(a)(3)(i).
IN 98-44 also states that the NRC staff will consider authorizing a delay of up to 2 years in implementing the next 10-year ISI program for piping only in order for the licensee to develop and obtain approval for the risk-informed ISI program for piping.Waterford 3 is currently in the third period of the second IS[ interval as defined by ASME Section XI Code for Inspection Program B. The second 10-year ISI interval began July 1997 and ends June 2007. Invoking the Code-allowed one-year extension extends the interval to June 2008.Entergy is planning to submit to the NRC staff a request for alternative to implement a risk-informed
/ safety-based inservice inspection (RISB) program at Waterford 3.Entergy plans to implement the RISB ISI program during RF-1 6 currently scheduled for the fall 2009. To accomplish this, Entergy requires approval of this request, which extends the second ISI interval to the end of RF-1 6 (approximately seventeen months beyond the Code-allowed one-year extension).
The Waterford 3 RISB process will be based upon ASME Code Case N-716, Alternative Piping Classification and Examination Requirements,Section XI Division 1, which is founded in large part on the RI-ISI process as described in Electric Power Research Institute
.(EPRI) Topical Report (TR) 112657 Rev. B-A, Revised Risk-Informed Inservice Inspection Evaluation Procedure.
The associated request for alternative will demonstrate a reduction in risk (or maintains risk neutrality) while substantially reducing worker exposure and undue burden. Because risk-informed ISI programs focus inspections (and inspection methods) on locations potentially susceptible to degradation while considering the consequence of piping failure, a more robust targeted inspection program can be defined.If the to-be-requested RI-ISI program, based on ASME Code Case N-716, is not accepted by the staff, Entergy plans to submit a different request for alternative to establish an RI-ISI program at Waterford 3 based on ASME Code Case N-578, which the staff has approved for several licensees.
With such a submittal, Entergy would also seek an additional extension of the third interval, if necessary.
In the unlikely event the staff does not approve a RI-ISI program based on either code case, Entergy would then perform the necessary Code-required examinations for the third interval.Table IWB-2412-1 requires that a minimum of 50% of the ASME Section XI examinations be completed by the end of the second period of an inspection interval.
By the end of the thirteenth refueling outage (RF-1 3), which was in the second period of the second interval, 62% of the piping weld examinations required by ASME Section XI had been Page 2 of 4 completed for Examination Categories B-F, B-J, C-F-1, and C-F-2.1 Therefore, Waterford 3 met the minimum requirement specified in Table IWB-2412-1.
By the end of the last refueling outage (RF-14), 65% of the required piping weld examinations have been completed.
During the time period needed for NRC review and approval of the RI-ISI program request, Entergy plans to perform required augmented inspection programs as committed to the staff in various correspondence.
For example, augmented inspections of piping locations in the break exclusion
'region are scheduled to be performed during RF-1 5 in accordance with Waterford 3 FSAR Section 6.6.8. Entergy will also continue to examine Alloy 600 welds as allowed by EPRI MRP-1 39 (Ref. 3)and as committed to the staff in Entergy letter CNRO-2007-00005, Inspection and Mitigation of Alloy 600/82/182 Pressurizer Butt Welds, dated February 21, 2007.Entergy is planning to submit the request for the Waterford 3 RISB Program following approval of the request submitted for Grand Gulf Nuclear Station (GGNS).2 Entergy expects the Waterford 3 request to be submitted after RF-1 5. Entergy intends to start implementing the RISB Program at Waterford 3 during the plant's third period of the second inspection interval.
As stated above, by the end of the previous refueling outage (RF-1 4), 65% of the piping weld examinations required by ASME Section XI have been completed in the second ISI interval for Examination Categories B-F, B-J, C-F-i, and C-F-2. To ensure that 100% of the required examinations are performed during the current ISI interval, 35% of the inspection locations selected for examination per the RISB process will be examined in the third period of the interval.
The third ISI interval will implement 100% of the inspection locations selected for examination per the program approved by the staff. Examinations shall be performed such that the period percentage requirements of ASME Section XI are met.IV. CONCLUSION 1 OCFR50.55a(a)(3) states: "Proposed alternatives to the requirements of (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." 1 Entergy transmitted this information to the NRC via letter W3F1 -2004-0010, Submittal of Owners Activity Report Forms for Inservice Inspection Performed during Refueling Outages 11 and 12, dated February 17, 2004.2 Entergy submitted the GGNS request via letter CNRO-2006-00043, Request forAltemative GG-ISI-002
-Request to Use ASME Code Case N-716, dated September 22, 2006.Page 3 of 4 As discussed in Section III above, the extension to the end of RF-1 6 would allow time for the NRC to review Waterford 3's risk-informed ISI submittal while not affecting future ISI intervals.
Therefore, Entergy requests authorization to perform the requested alternative to the Code requirement pursuant to 10 CFR 50.55a(a)(3)(i).
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