NRC-02-0071, ECCS Cooling Performance Evaluation Model Report
| ML021980469 | |
| Person / Time | |
|---|---|
| Site: | Fermi  |
| Issue date: | 07/10/2002 |
| From: | O'Connor W Detroit Edison |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| NRC-02-0071 | |
| Download: ML021980469 (2) | |
Text
William T. O'Connor, Jr.
Vice President, Nuclear Generation Fermi 2 6400 North Dixie Hwy., Newport, Michigan 48166 Tel: 734.586.5201 Fax: 734.586.4172 Detroit Edison A DTE Energy Company 10CFR50.46 July 10, 2002 NRC-02-0071 U. S. Nuclear Regulatory Commission Attention: Document Control Desk Washington D C 20555-0001
References:
- 1) Fermi 2 NRC Docket No. 50-341 NRC License No. NPF-43
- 2) Detroit Edison Letter, Douglas R. Gipson to USNRC, "30-Day 10CFR50.46 Special Report Plant Specific ECCS Evaluation Changes",
dated May 28, 1996 (NRC-96-0052)
- 3) Detroit Edison Letter, W. T. O'Connor, Jr. to USNRC, "ECCS Cooling Performance Evaluation Model Report",
dated December 19, 2000 (NRC-00-0074)
- 4) Detroit Edison Letter, W. T. O'Connor, Jr. to USNRC, "ECCS Cooling Performance Evaluation Model Report",
dated June 7, 2001 (NRC-01-0046)
Subject:
ECCS Cooling Performance Evaluation Model Report In accordance with 1 OCFR50.46, "Acceptance criteria for emergency core cooling systems for light-water nuclear power reactors," this report is being submitted to describe changes to or errors in an acceptable evaluation model used for calculating
USNRC NRC-02-0071 Page 2 Emergency Core Cooling Systems (ECCS) performance. References 2, 3 and 4 describe errors in the evaluation model previously reported to the NRC.
On June 13, 2002 Global Nuclear Fuel (GNF) informed Detroit Edison, in General Electric (GE) 10CFR50.46 Notification Letters 2002-01 and 2002-02, of two additional errors found in the GE SAFER/GESTR-LOCA code. One of these errors resulted in too low a value being calculated for the core spray injection elevation.
The other error resulted in too high a value used for the reactor pressure vessel initial liquid inventory because the steam dryer pressure drop was not properly accounted for. The total effect of the two errors results in an increase in the peak clad temperature (PCT) by 45 degrees Fahrenheit. With the 45 degree Fahrenheit increase in PCT, the current Licensing Basis PCT for Fermi 2 is 1757 degrees Fahrenheit and there still is 443 degrees Fahrenheit margin to the 2200 degrees Fahrenheit PCT limit given in 1 OCFR50.46.
Detroit Edison will continue to track future changes and errors in the SAFER/GESTR-LOCA Loss-of-Coolant Accident Analysis evaluation models to ensure that the analyzed PCT remains below the 10CFR50.46 limits, and to ensure that the 10CFR50.46 reporting requirements are met. Detroit Edison has no immediate plans to reanalyze the SAFER/GESTR-LOCA Loss-of-Coolant Accident Analysis for Fermi 2.
Should you have any questions or require additional information, please contact Mr. Norman K. Peterson of my staff at (734) 586-4258.
Sincerely, cc:
T. J. Kim M. A. Ring NRC Resident Office Regional Administrator, Region III Supervisor, Electric Operators, Michigan Public Service Commission