ML20196J270
| ML20196J270 | |
| Person / Time | |
|---|---|
| Site: | Catawba, McGuire  |
| Issue date: | 07/25/1997 |
| From: | Tuckman M DUKE POWER CO. |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| References | |
| NUDOCS 9708040133 | |
| Download: ML20196J270 (4) | |
Text
-,
--- = _
I FN Duke Power Company Il,;.
Of-A Duke Ewy Company 422 South Church Screet A wam %
P.O. Box 1244 Charlotte, NC 28201-1244 July 25, 1997 s
l U.
S. Nuclear Regulatory Commission Washington, D. C.
20555 Attention: Document Control Desk
Subject:
McGuire Nuclear Station, Unit 1 Docket No. 50-369 Catawba Nuclear Station, Units 1 and 2 Docket Nos. 50-413 and
-414 R0 port Pursuant to 10CFR50.46 Changes To Or Errors In an ECCS Evaluation Model 10 CFR50.4 6 (a) (3) (ii) requires the reporting of changes to t
or err.'rs in an ECCS evaluation model (D4), or in an application of the EM, which affect the LOCA peak clad temperature (PCT) calculation.
If the effect on the
+
calculation is significant (>50 F), the report is required to be made within 30 days.
For the McGuire and Catawba Nuclear Stations, the current large-break LOCA analyses use l
the Framatome Technologies, Inc.,
By letter-dated June 27, 1997, FTI notified Duke Energy of an error in the FTI LOCA EM in the modeling of decay heat from actinides, in which the decay heat was underpredicted.
This error was also communicated to the NRC by FTI in a letter l
dated June 27, 1997 from Mr.
J. H. Taylor to the Document l
Control Desk.
The details of the error are included in the FTI letter to NRC, and are not repeated here.
FTI has reanalyzed the large-break LOCA analyses of record for each of the four McGuire and Catawba units, and has I
l
. determined that the effect of the error exceeds 50 F for the l'
LOCA analysis applicable to the units for which the steam jp{}[/
generators have been replaced (McGuire Unit 1 and Catawba Unit 1). For those units the magnitude of the error is 77 F.
1 For Catawba Unit 2, the reanalysis with the correction also included an offsetting 2% decrease in allowable core power peaking.
The resulting PCT increase is 9"F.
Since an analysis result for Catawba Unit 2 without the offsetting peak reduction was not provided, it is possible that the 9700040133 970725 j l{l{llll l[
^
PDR ADOCK o 369 DR
j U.
S. Nuclear Regulatory Commission July 25, 1997 Page 2 50 F PCT increase criterion may have also been exceeded for Catawba Unit 2.
For McGuire Unit 2 the impact of the error is a PCT increase of 20 F; therefore, this 30-day report does not apply to McGuire Unit 2.
The small-break LOCA analyses for McGuire Unit 1 and Catawba Unit 1 are also affected by the actinide decay heat error.
The limiting SBLOCA PCT, including the error correction, is 1343 F.
LOCA analyses for all four McGuire and Catawba units, with the FTI EM actinide decay heat error correction included, are now in place which meet the acceptance criteria of 10CER50.46 (All PCTs < 2200 F).
The core power distribution monitoring is being performed consistent with Technical Specifications to ensure that the core power peaking assumed in the LOCA analysis is not exceeded.
If there are any questions, please call Scott Gewehr at (704) 382-7581.
Very truly yours,
- 5.
M.
S.
Tuckman Executive Vice President i
-. -~... -
j "U.
S. Nuclear Regulatory Commission July 25, 1997 Page 3 cc:
Mr. V. Nerses, Project Manager Office of Nuclear Reactor Regulation U. S. Nuclear Regulatory Commission Mail Stop 14H25, OWFN Washington, D. C.
20555 Mr. P. S. Tam, Project Manager Office of Nuclear Reactor Regulation U. S. Nuclear Regulatory Commission Mail Stop O-14 H25 Washington, D. C.
20555 Mr. L. A. Reyes, Regional Administrator U.S. Nuclear Regulatory Commission - Region II 101 Marietta Street, NW - Suite 2900 Atlanta, Georgia 30323 Mr. S. M. Sheaffer Eenior Resident Inspector McGuire Nuclear Station Mr. R. J. Freudenburger Senior Resident Inspector Catawba Nuclear Station l
l l
l t
1 l'
1 1
i
,U.
S. Nuclear Regulatory Commission July 25, 1997 Page 4 1
bxc: G. A. Copp M. T. Cash (MNS)
S. A..Gewehr M. S. Kitlan (CNS)
ELL j
1 l
i l
1 l
I l
I I
I l
l