ML091350568

Arkansas Nuclear One, Units 1 and 2 - Annual 10 CFR 50.46 Report for Calendar Year 2008 Emergency Core Cooling System Evaluation Changes

ML091350568
Person / Time
Site:	Arkansas Nuclear
Issue date:	05/15/2009
From:	Bice D B Entergy Operations
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
0CAN050903
Download: ML091350568 (5)

Text

0CAN050903

May 15, 2009

U.S. Nuclear Regulatory Commission

Attn: Document Control Desk Washington, DC 20555

SUBJECT:

Annual 10 CFR 50.46 Report for Calendar Year 2008 Emergency Core Cooling System Evaluation Changes Arkansas Nuclear One, Units 1 and 2 Docket Nos. 50-313 and 50-368

License Nos.

DPR-51 and NPF-6

REFERENCE:

1. Entergy Letter to the NRC, "10 CFR 50.46 Report - Significant Change in Peak Cladding Temperature," dated April 1, 2009 (1CAN040902)

Dear Sir or Madam:

10 CFR 50.46(a)(3)(ii) requires licensees to report annually each change to or error discovered in an acceptable evaluation model or in the application of such model for the emergency core cooling system that affects the peak cladding temperature (PCT). Entergy Operations, Inc. (Entergy) has reviewed the 2008 small and large break loss-of-coolant accident (LOCA) PCT evaluations for both Arkansas Nuclear One, Units 1 and 2 (ANO-1 and ANO-2).

A summary / overview of the information required to be submitted each year is attached to this submittal.

This fulfills the reporting requirements referenced above.

Reference 1 provided notification of a change to the ANO-1 small break LOCA PCT of greater than 50°F from the previous temperature calculated for the small break LOCA limiting plant transient. This occurred in 2009 and therefore, does not impact this report. Further discussion of this change will be in the annual report for the calendar year 2009.

This submittal contains no new commitments.

Entergy Operations, Inc. 1448 S.R. 333 Russellville, AR 72802 Tel 479-858-4710 David B. Bice Acting Manager, Licensing Arkansas Nuclear One

0CAN050903 Page 2 of 2

If you have any questions or require additional information, please contact me.

Sincerely,

DBB/rwc

Attachment:

Summary / Overview of Information for ANO-1 & 2 10 CFR 50.46 Annual Report for 2008

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. Kaly Kalyanam MS O-8B1 One White Flint North 11555 Rockville Pike

Rockville, MD 20852

Mr. Bernard R. Bevill Arkansas Department of Health Radiation Control Section 4815 West Markham Street Slot #30 Little Rock, AR 72205 Attachment to 0CAN050903 Summary / Overview of Information for ANO-1 & 2 10 CFR 50.46 Annual Report for 2008

Attachment to 0CAN050903

Page 1 of 2

SUMMARY

/ OVERVIEW OF INFORMATION FOR ANO-1 & 2 10 CFR 50.46 ANNUAL REPORT FOR 2008 Analysis of Record (AOR)

Peak Cladding Temperature (PCT), o F Evaluation Model (EM) Used AOR Date Adjustment, o F As of End of Year (EOY) 2007 Net PCT, o F @ EOY 2007 New Adjustments for 2008 Net PCT, o F @ EOY 2008 ANO-1 (1) Small Break Loss-of-Coolant Accident (SBLOCA) 1179.7 RELAP5/MOD2-B&W JUL 2005 0 1179.7 None 1179.7 Large Break Loss-of-Coolant Accident (LBLOCA) 2008.1 RELAP5/MOD2-B&W AUG 2005 Note 1 2000 (Note 1) Full core B-HTP (Note 1) 2008.1 (Note 1) ANO-2 (2) SBLOCA 2137 S2M JUN 2006 0 2137 None (Note 2) 2137 (Note 2) LBLOCA 2168 1999EM NOV 2004 0 2168 None (Note 2) 2168 (Note 2) NOTES:

1. ANO-1 completed transition to B-HTP fuel with its 1R21 reload (Fall 2008). The previous LBLOCA AOR was performed for a full core of B-9 fuel assemblies using the RELAP5/MOD2-B&W EM and provided a limiting PCT of 2000 oF (still the limiting PCT as of EOY 2007). The mixed-core LBLOCA analyses showed a reduction in PCT to 1981.4 oF for the B-HTP fuel and < 2000 o F for B-9 fuel. With completion of the transition to B-HTP fuel, the B-9 and mixed-core PCTs are no longer applicable to ANO-1 and the analyses associated with a full core of B-HTP fuel performed in 2005 become the new AOR. Transition to B-HTP fuel had no impact on the SBLOCA AOR PCT results.

Attachment to 0CAN050903

Page 2 of 2

2. ANO-2 loaded 88 Optimized ZIRLO fuel assemblies (~1/2 core) in its Spring 2008 outage. The limiting PCTs for this fuel are 2111 oF for SBLOCA and 2144 oF for LBLOCA. These PCTs were also determined using the S2M and 1999EM evaluation models for SBLOCA and LBLOCA, respectively. Both sets of analyses were performed in February 2007. Since the SBLOCA and LBLOCA PCTs for ZIRLO fuel are more limiting, these temperatures continue to be reported here. Complete transition to Optimized ZIRLO is scheduled to occur with the 2R20 reload (Fall 2009).

REFERENCES:

1. PWROG letter OG-09-151 dated April 13, 2009

2. Westinghouse letter LTR-LAM-09-11 dated January 30, 2009