ML19326A738
| ML19326A738 | |
| Person / Time | |
|---|---|
| Site: | Oconee, Crystal River  |
| Issue date: | 02/04/1974 |
| From: | Rodgers J FLORIDA POWER CORP. |
| To: | |
| References | |
| NUDOCS 8003030875 | |
| Download: ML19326A738 (2) | |
Text
.-
cceen Y%o q.e
(
30% 00e4 LA y
...a
.M..........
February 4, 1974 Donald F. Knuth, Director The Directorate of Regulatory Operations U. S. Atomic Energy Commission Washington, D. C.
20545
Subject:
Crystal River Plant Unit #3 Docket 50-302
Dear Mr. Knuth:
i
'l On Wednesday, January 30, 1974, we advised the Director of Regulatory Operations, Region II in Atlanta by telephone, that we had
~
been notified by B&W Company that certain revisions were required in the Specific Heat Curve for UO2 Fuel as utilized in some of their transient Computer Codes. This change will be reflected in a higher value of the specific heat for elevated fuel temperatures.
(
t.m/
Florida Power Corporation has determined that in our opinion this change constitutes a significant deficiency in that, had it remained uncnanged, Crystal River Unit #3 could have been operated in such a manner that safety limitations wculd have been exceeded. Therefore, we are filing this report pursuant to the requirements of AEC 10CFR50.55e.
The studies necessary to quantify the impact that this revision may have on the safety analyses reported in the SAR are underway. The general effect will be a change in the level of stored energy in the fuel as well as in the time response of some transients. Based on B&W's present evaluation, this revision will not affect the steady-state analysis because the basic data from which the curve is derived are valid; it is these basic data that are used for the steady-state calcu-i lations. The particular effect on kinetic behavior can be determined only by an evaluation of the safety analyses. To indicate the magnitude of this revision, preliminary calculations on Oconee 2 show that a reduction in the maximum linear heat rate of less than 1.0 KW/ft should offset the effects of this change in specific heat.
l
,e' h
i
/
L\\f,. ,
3 1418 (m)
W l
8003030bY E f General Office 32o1 Thirty-rourtn street soutn. P.O. Box 14042. St. Petersburg. F anda 33733 813-866-5151
i
)
Donald F. Knuth February 4, 1974 Page.
We have been advised that the correction of this deficiency will not require any physical component design changes. The result of lowering the maximum allowable linear heat rate will result in modifications to the Technical Specifications with regard to operating restrictions. In addition to this change in B&W's transient computer codes, the recently published AEC Final Acceptance Criterion for ECCS will require.that considerable re-analyses be performed which also have a bearing on the maximum allowable linear heat rates. Both of these considerations will be fully taken into account and documented in a timely fashion prior to finalization of the Crystal River Unit #3 Technical Specifications.
We will keep you advised on the status of B&W's continuing investigation. We understand that B&W will be discussing this infor-mation with you on a generic basis in an effort to keep you fully 4
informed of further developments.
If you require any further information regarding this matter, please advise us.
Very truly yours,
\\
Y..( W Y I' idh Joel T. Rodgers Assistant Vice President ec: Norman C. Moseley Director, Region II
%/
p l
l i.
_~
-