L-MT-09-115, 2009 Report of Changes and Errors in ECCS Evaluation Models
| ML093570452 | |
| Person / Time | |
|---|---|
| Site: | Monticello  |
| Issue date: | 12/22/2009 |
| From: | O'Connor T Northern States Power Co, Document Control Desk, Xcel Energy |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| L-MT-09-115 | |
| Download: ML093570452 (3) | |
Text
December 22,2009 L-MT-09-115 10 CFR 50.46(a)(3)
U.S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, DC 20555 Monticello Nuclear Generating Plant Docket: 50-263 Renewed License No.: DPR-22 2009 Report of Chanqes and Errors in ECCS Evaluation Models
References:
- 1) GE Report, NEDC-32514P, Revision 1, "Monticello SAFERIGESTR LOCA Loss of Coolant Accident Analysis," dated October 1997.
- 2) GE Report, GE-NE-J1103878-09-02P, "Monticello ECCS-LOCA Evaluation for GE14," GE Proprietary Information, dated August 2001.
- 3) NSPM to NRC letter, "2008 Report of Changes and Errors in ECCS Evaluation Models," (L-MT-08-081), dated December 30, 2008.
Pursuant to 10 CFR 50.46(a)(3), the Northern States Power Company, a Minnesota Corporation (NSPM), is providing the annual report of changes or errors identified in the Emergency Core Cooling System (ECCS) evaluation models or their application for the Monticello Nuclear Generating Plant (MNGP). This report is for the period between July 2008 and July 2009.
The MNGP Loss of Coolant Accident (LOCA) analyses of record (AOR) are contained within the General Electric (GE) reports submitted for the MNGP rerate (Reference 1) and the LOCA analysis for the GE14 fuel type (Reference 2). One GE fuel type has been in use over this time period, the GE14 fuel type. The current operating cycle (Monticello Cycle 25) core loading consists solely of the GE14 fuel design type.
During the period covered, no notifications of any changes or errors resulting in a change to the calculated Peak Clad Temperature (PCT) were received from GE. Therefore, the licensing basis PCTs and the PCT Summary provided in Table 1 of Enclosure 1 are unchanged from the last annual report (Reference 3).
2807 W County Road 75 Monticello, MN 55362
L-MT-09-115 Document Control Desk Page 2 of 2 The current adjusted licensing basis PCT for the fuel type used at the MNGP during the period covered by this report is:
Licensina Basis Fuel Tvpe PCT (OF) provides an updated summary table of the applicable changes and errors in the LOCA analyses from when the last analyses of record were pelformed.
Summarv of Commitments
/
ommitments or changes any existing commitments.
Generating Plant Northern States Power Company-Minnesota Enclosure cc:
Regional Administrator, Region Ill, USNRC Project Manager, Monticello Nuclear Generating Plant, USNRC Resident Inspector, Monticello Nuclear Generating Plant, USNRC
L-MT-09-115 Page 1 of 1 TABLE I -
SUMMARY
OF MONTICELLO LOCA CHANGES AND ERRORS INVOLVING CHANGES IN PEAK CLADDING TEMPERATURE (PCT)
References
- 1. GE Report: NEDC-32514P, Revision 1, "Monticello SAFERIGESTR-LOCA Loss-of-Coolant Accident Analysis" dated October 1997. (This report is Exhibit G of Revision 1 to License Amendment Request Dated July 26, 1996, Supporting Monticello Nuclear Generating Plant Power Re-rate Request Program.)
Licensing Basis PCT ( O F )
GE14
< 1960
- 15
+ 30 0
45 0
+ 15
< 1975 Applicable Analysis or Error Description NEDC-32514P, Rev 1, "Monticello SAFERIGESTR-LOCA Loss of Coolant Accident Analysis" GE-NE-J1 1 03878-09-02Pj "Monticello ECCS-LOCA Evaluation for GE14" "lmpact of SAFER LevelNolume Table Error on PCT (Notification Letter 2003-01)
Level and volume tables used by SAFER were not updated when a revised initial water level was implemented.
"lmpact of Top Peaked Power Shape for Small Break LOCA Analysis" (Notification Letter 2006-01)
Small Break LOCA analyses had assumed a mid-peaked axial power shape consistent with the DBA break analysis. It was determined that a top-peaked axial power shape can result in higher calculated PCT.
- 2. GE-NE-J1 1 03878-09-02P, "Monticello ECCS-LOCA Evaluation for GE14," GE Proprietary Information, dated August 2001.
Ref.
1 2
3 4
- 3. 10 CFR 50.46 Notification Letter 2003-01, "lmpact of SAFER LevelA/olume Table Error on the Peak Clad Temperature (PCT)," GE Proprietary Information, dated May 6, 2003.
Sum of absolute value of changes during the current reporting period.
Sum of absolute value of changes since last AOR.
Algebraic sum of changes during the current reporting period.
Algebraic sum of changes since last AOR.
Current Adjusted Peak Cladding Temperature