L-MT-19-003, Thirty Day Report of Changes in the Emergency Core Cooling System Evaluation Models Pursuant to 10 CFR 50.46
| ML19028A256 | |
| Person / Time | |
|---|---|
| Site: | Monticello  |
| Issue date: | 01/28/2019 |
| From: | Church C Northern States Power Company, Minnesota, Xcel Energy |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| L-MT-19-003 | |
| Download: ML19028A256 (3) | |
Text
2807 West County Road 75 Monticello, MN 55362 800.895.4999 xcelenergy.com January 28, 2019 ATTN: Document Control Desk U.S. Nuclear Regulatory Commission Washington, DC 20555-0001 Monticello Nuclear Generating Plant Docket No. 50-263 Renewed Facility Operating License No. DPR-22 fl Xcel Energy*
RESPONSIBLE BY NATU R E L-MT-19-003 10 CFR 50.46 (a)(3)(ii)
Thirty Day Report of Changes in the Emergency Core Cooling System Evaluation Models Pursuant to 10 CFR 50.46 Pursuant to 10 CFR 50.46(a)(3)(ii}, the Northern States Power Company, a Minnesota corporation (NSPM), doing business as Xcel Energy, is providing this 30 day report concerning changes or errors identified in the Emergency Core Cooling System (ECCS) evaluation for the Monticello Nuclear Generating Plant (MNGP).
This thirty-day report is being made due to recent issuance of a notification letter from Framatome for changes or errors to the current, Analysis of Record (AOR). These changes exceeded the 50°F threshold in 10 CFR 50.46(a)(3)(i) for a significant increase in peak cladding temperature (PCT).
Provided within Enclosure 1 is a summary of the changes or errors identified in the Framatome's 10 CFR 50.46 PCT Reporting - Heatup Analysis Input Issue. This error pertains only to the ATRIUM 10XM fuel.
The adjusted licensing basis PCT is 2100°F for the ATRIUM' 1 0XM fuel. This PCT is 100°F below the 2200°F acceptance criterion of 10 CFR 50.46(b )(1 ). This provides sufficient margin to justify taking no further action.
Should you have questions regarding this letter, please contact Mr. David Gerads at (763) 295-1046.
Summary of Commitments This letter makes no new commitments and no revisions to existing commitments.
~t~~
Site Vice President, Monticello Nuclear Generating Plant Northern States Power Company - Minnesota Enclosure (1) cc:
Administrator, Region Ill, USNRC Project Manager, Monticello, USNRC Resident Inspector, Monticello, USNRC
ENCLOSURE 1 Monticello Nuclear Generating Plant Table 1 Summary of Monticello LOCA Changes and Errors Involving Changes in Peak Cladding Temperature (PCT) for Atrium 10XM Fuel
TABLE 1 -
SUMMARY
OF MONTICELLO LOCA CHANGES AND ERRORS INVOLVING CHANGES IN PEAK CLADDING TEMPERATURE (PCT) FOR ATRIUM 10XM FUEL Applicable Analysis or Error/Change Description Ref.
Licensing Basis PCT(°F) 10XM ANP-3558P Revision 0, Monticello LOCA MAPLHGR Limits for EPU/EFW with ATRIUM 10XM Fuel and Revised ECCS Parameters 2-1 2034 MSIV closure The impact of this MSIV closure change was estimated for the Monticello LOCA break spectrum and exposure-dependent MAPLHGR analyses.
2-2
+51 Updated steam dryer information A review of the steam dryer related inputs identified a need to update the input for the dryer region.
2-3
+5 Incorrect power heatup analysis The code AUTOHUP generated an incorrect input to the heatup analysis.
2-4
+10 Sum of absolute value of changes since the last 10 CFR 50.46 report (Reference 2-5).
10 Sum of absolute value of changes since last AOR (Reference 2-1).
66 Algebraic sum of changes since the last 10 CFR 50.46 report (Reference 2-5).
+10 Algebraic sum of changes since last AOR (Reference 2-1).
+66 Current Adjusted Peak Cladding Temperature 2100 References 2-1.
ANP-3558P Revision 0, Monticello LOCA MAPLHGR Limits for EPU/EFW with ATRIUM 10XM Fuel and Revised ECCS Parameters, January 2017.
2-2.
FS1-0032297, Revision 1.0, Monticello 10 CFR 50.46 PCT Reporting for ATRIUM 10XM Fuel Through May 2017, May 2017.
2-3.
FS1-0039467, Revision 1.0, Monticello 10 CFR 50.46 PCT Reporting Estimates for ATRIUM 10XM Fuel between August 2017 and August 2018, August 2018.
2-4.
FS1-0041394 Revision 1.0, Monticello 10 CFR 50.46 PCT Error Reporting - Heatup Analysis Input Issue, Framatome Inc., January 2019.
2-5.
L-MT-18-053, Thirty Day Report of Changes in Emergency Core Cooling System Evaluation Models Pursuant to 10 CFR 50.46, September 2018.