L-20-138, Report of ECCS Model Changes and Errors Pursuant to 10 CFR 50.46
| ML20129H958 | |
| Person / Time | |
|---|---|
| Site: | Harris  |
| Issue date: | 05/06/2020 |
| From: | Payne F Energy Harbor Nuclear Corp |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| L-20-138 | |
| Download: ML20129H958 (4) | |
Text
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~ harbor Perry Nuclear Power Plant 10 Center Road P.O. Box 97 Perry, Ohio 44081 Frank R. Payne 440-280-5382 Site Vice President, Peny Nuclear May 6, 2020 L-20-138 10 CFR 50.46 ATTN: Docum~nt Control Desk U.S. Nuclear Regulatory Commission Washington, DC 20555-0001
SUBJECT:
Perry Nuclear Power Plant Docket No. 50-440, License No. NPF-58 Report of ECCS Model Changes and Errors Pursuant to 10 CFR 50.46 On April 14, 2020, GE-Hitachi Nuclear Energy Americas (GEH) provided a notification to the Perry Nuclear Power Plant (PNPP) that identified an error in an acceptable evaluation model regarding the emergency core cooling system (ECCS) - loss of coolant accident (LOCA) analyses. Pursuant to 10 CFR 50.46, "Acceptance criteria for emergency core cooling systems for light-water nuclear power reactors," Energy Harbor Nuclear Corp. is notifying the Nuclear Regulatory Commission (NRC) of the error.
The identified errors were in the PRIME code, which calculates fuel rod conditions as input to the ECCS LOCA evaluation model. The identified errors include zircaloy irradiation growth after a breakaway neutron fluence, incorrect (zircaloy) thermal conductivity applied to the zirconium (Zr) barrier for cladding temperature drop, and gap conductance during pellet-cladding gap closure.
PRIME provides fuel rod conditions as input to SAFER and TRACG evaluation models for ECCS LOCA calculations. For these findings with the PRIME code, an assessment was performed for a span of representative plants with the SAFER and TRACG evaluation models. Using input from the corrected PRIME code, the results confirmed a peak cladding temperature (PCT) impact of 0°F.
In the previous cycle (within the last 36 months), PNPP's reactor core included both the GE14 and GNF2 fuel types. During the refueling outage that ended in April 2019, PNPP went to a complete core of GNF2 fuel. The assessment addresses the impact on both the GE14 LOCA analysis and the GNF2 LOCA analysis.
Perry Nuclear Power Plant L-20-138 Page 2 PNPP's GNF2 SAFER/PRIME LOCA assessment identified the current PCT for GNF2 is 1610°F. The addition of the 0°F results in an unchanged GNF2 PCT of 1610°F. The revised GNF2 PCT is less than the 2200°F licensing basis peak cladding temperature limit. As such, a compensatory power de-rate or a change to thermal limits is not required.
The absolute sum of all GNF2 SAFER/PRIME LOCA analysis errors is 20°F and remains below the 50°F limit. Since the revised GNF2 PCT did not exceed 2200°F and the revised absolute sum of all errors did not exceed 50°F, an NRG 30-day report is not required.
The current PCT for GE14 is 1555°F. The addition of the 0°F results in an unchanged GE14 PCT of 1555°F. The revised GE14 PCT is less than the 2200°F licensing basis peak cladding temperature limit.
The absolute sum of all GE14 SAFER/PRIME LOCA analysis errors is 125°F and is above the 50°F limit. Since the GE14 absolute sum of all errors exceeded 50°F, an NRG 30-day report is required. A summary of the PNPP 10 CFR 50.46 changes and errors is attached.
There are no regulatory commitments contained in this submittal. If there are any questions or if additional information is required, please contact Mr. Phil H. Lashley, Acting Manager - Nuclear Licensing and Regulatory Affairs, at (330) 315-6808.
Sincerely, j\ J
- I: r---
Payne
~ ii Attach l ,,
Perry Nuclear Power Plant 10 CFR 50.46 Changes and Errors cc: NRG Region Ill Administrator NRG Resident Inspector NRG Project Manager
Attachment L-20-138 Perry Nuclear Power Plant 10 CFR 50.46 Changes and Errors Page 1 of 2 Vendor Summary of Change/Error Licensing Basis Peak Licensee Report Notification Cladding Temperature of Notification Number (PCT) lmoact (Accession No) 2001-02 Impact of SAFER 1 PCT impact for GE14 ML020710641 pressure rate fuel is +5°F.
inconsistency error.
2002-01 Impact of SAFER core PCT impact for GE14 ML030710170 spray injection elevation fuelis+15°F.
error.
2002-02 Impact of SAFER bulk PCT impact for GE 14 ML030710170 water level error. fuel is 0°F.
2002-04 Impact of SAFER04 PCT impact for GE14 ML030710170 computer platform fuel is 0°F.
change.
2002-05 Impact of error in PCT impact for GE 14 ML030710170 WEVOL 2 calculation of fuel is 0°F.
downcomer free volume.
2003-01 lmp~ct of SAFER level/ PCT impact for GE 14 ML040710502 volume table error. fuel is +5°F.
2003-03 Impact of SAFER initial PCT impact for GE14 ML040710502 steam separator pressure fuel is 0°F.
drop.
2003-05 Impact of postulated post- PCT impact for GE14 ML040710502 LOCA3 hydrogen-oxygen fuel is 0°F.
recombination .
2006-01 Impact of top peaked PCT impact for GE14 ML062490520 power shape for small fuel is 0°F. ML070390113 break LOCA analysis.
2011-02 Impact of database error PCT impact for GE14 ML112290919 for heat deposition for fuel is +25°F.
10X10 fuel bundles.
2011-03 Impact of updated PCT impact for GE14 ML112290919 formulation gamma heat fuel is -40°F.
deposition to channel wall for 10X10 fuel bundles.
2012-01 Impact of change in fuel PCT impact for GE14 ML12353A320 properties from GESTR4 fuel is +20°F.
to PRIME 5
- Attachment L-20-138 Page 2 of 2 Perry Nuclear Power Plant 10 CFR 50.46 Changes and Errors (Continued)
Vendor Summary of Change/Error Licensing Basis Peak Licensee Report Notification Cladding Temperature of Notification Number (PCT) Impact (Accession No) 2014-01 Impact of use of a new PCT impact for GE14 ML14170A178 version of SAFER04A. fuel is 0°F 2014-02 Impact of system mass PCT impact for GE14 ML14170A178 diverqence error. fuel is 0°F 2014-03 Impact of minimum delta PCT impact for GE14 ML14170A178 pressure error. fuelis-15 ° F 2014-04 Impact of counter current PCT impact for GE14 ML14170A178 flow limitation error. fuel is 0°F 2017-02 Impact of fuel rod plenum PCT impact for GE14 ML17233A279 temperature update. fuel is 0°F 2019-05 Impact of lower control rod PCT impact for GE14 ML20086J339 drive housing interface fuel is 0°F backward leakaqe path.
2020-01 PRIME coding errors for PCT impact for GE14 This submittal zircaloy irradiation growth fuel is 0°F and Zr barrier thermal conductivity as input to LOCA analyses.
TOTAL Summation of the 125°F absolute values of the changes/errors Notes:
- 1. SAFER - Name of the code developed by General Electric Company that calculates long term reactor vessel inventory and peak cladding temperature for LOCA and loss of inventory events.
- 2. WEVOL - Name of a code that is used to calculate the weight and volume inputs for jet pump plant SAFER analyses.
- 3. LOCA - Loss of coolant accident.
- 4. GESTR - General Electric stress and thermal analysis of fuel rods.
- 5. PRIME - Name of the model for analysis of fuel rod thermal - mechanical performance.