ML16154A320
| ML16154A320 | |
| Person / Time | |
|---|---|
| Site: | Oconee  |
| Issue date: | 05/04/1993 |
| From: | Hampton J DUKE POWER CO. |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| Shared Package | |
| ML16154A321 | List: |
| References | |
| NUDOCS 9305140203 | |
| Download: ML16154A320 (4) | |
Text
ACCELERATU DOCUMENT DISTRIBUTION SYSTEM REGULATO INFORMATION DISTRIBUTION 9STEM (RIDS)
ACCESSION NBR:9305140203 DOC.DATE: 93/05/04 NOTARIZED: NO DOCKET #
FACIL:50-269 Oconee Nuclear Station, Unit 1, Duke Power Co.
05000269 AUTH.NAME AUTHOR AFFILIATION HAMPTON,J.W.
Duke Power Co.
RECIP.NAME RECIPIENT AFFILIATION R
Document Control Branch (Document Control Desk)
SUBJECT:
Submits written followup to 930504 telcon request for enforcement discretion from TS 4.7.1 re control rod trip time test.On 930504,two control rods declared inoperable as D
result oftest data questioning rod trip times.
DISTRIBUTION CODE: A001D COPIES RECEIVED:LTR ENCL j SIZE:,
S TITLE: OR Submittal: General Distribution NOTES:
A RECIPIENT COPIES RECIPIENT COPIES ID CODE/NAME LTTR ENCL ID CODE/NAME LTPR ENCL D
PD2-3 LA 1
1 PD2-3 PD 1
1 WIENS,L 2
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INTERNAL: ACRS 6
6 NRR/DE/EELB 1
1 NRR/DORS/OTSB 1
1 NRR/DRCH/HICB 1
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NRR/DSSA/SCSB 1
0 NRR/DSSA/SPLB 1
1 NRR/DSSA/SRXB 1
1 NUDOCS-ABSTRACT 1
1 OC/LFMB 1
0 OGC/HDS2 1
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1 EXTERNAL: NRC PDR 1
1 NSIC 1
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NOTE TO ALL "RIDS" RECIPIENTS:
PLEASE HELP US TO REDUCE WASTE! CONTACT THE DOCUMENT CONTROL DESK, S
ROOM P1-37 (EXT. 504-2065) TO ELIMINATE YOUR NAME FROM DISTRIBUTION LISTS FOR DOCUMENTS YOU DON'T NEED!
TOTAL NUMBER OF COPIES REQUIRED: LTTR 22 ENCL 19
0 I
Duke Power Company J W HAMFTN Oconee Nuclear Site Vice President P.O. Box 1439 (803)885-3499 Office Seneca, SC 29679 (803)885-3564 Fax DUKE POWER May 4, 1993 U. S. Nuclear Regulatory Commission
-Attention: Document Control Desk Washington, DC 20555
Subject:
Oconee Nuclear Station, Unit 1 Docket Nos. 50-269 T.S. 4.7.1 Control Rod Trip Time Test Request for Enforcement Discretion This letter constitutes written followup of a request for enforcement discretion from the requirements of Technical Specification (TS) 4.7.1 which was made via telephone between Duke Power personnel and members of the NRC staff on May 4, 1993 at 10:00am.
This emergency relief from compliance with the requirements of the TS was requested to avoid an unnecessary forced shutdown for Oconee Unit 1.
At 09:00 on May 4, 1993 two Unit 1 control rods were declared inoperable as a result of test data which cast doubt on the ability of the rods to meet the trip times required by TS 4.7.1.
This action requires that in accordance with TS 3.5.2.2.e that Unit 1 be in hot standby within 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> (e.g. by 21:00 on May 4, 1993).
Unit 1 is-currently operating at 100% full power and will begin power reduction at approximately 15:00 on May 4,
1993 if this request is not granted. Unit 2 is currently in cold shutdown for a refueling outage.
Unit 3 is currently operating at 100% full power. Units 2 and 3 are unaffected by this request.
In order to avoid an unnecessary forced shutdown and draindown of Oconee Unit 1, I request NRC approval for use of an interim acceptance criteria for control rod drop time on Oconee Unit 1.
Specifically, I request that Control Rod Group 1, Rod 8 and Group 2,
Rod 5 be considered operable with an insertion time of 52 seconds provided that: 1) the average insertion time for the remaining rods in Group 1 and the average insertion time for the remaining rods in Group 2 is 5 1.50 seconds and 2) the core average negative reactivity insertion rate is within the assumptions of the safety analysis. This acceptance criteria would apply until the end of the current fuel cycle for Oconee Unit 1 (end of cycle 15, currently scheduled for April 1994).
This acceptance criteria for rod drop time would apply rather than the existing limit TS 4.7.1 of 1.66 seconds from the fully withdrawn position to 3/4 insertion.
The interim acceptance criteria is considered to be acceptable since the assumptions of the safety analysis will be met.
9305140203 930504_8 PDR ADOCK" 05000269 P
PDR Printed on recycled paper
Document Control Desk Page 2 Note that although the rod drop time may be slightly outside the current test acceptance criterion for the two Unit 1 rods, there is a high level of confidence that the rods will trip into the core if called upon by the reactor protection system.
This level of confidence is provided by the following information:
the trend from trip time testing has shown a reduction in speed, however it has not shown any indication it is binding; although the drop time may be slow, it is not significantly far off from the acceptance criteria; there has been no drastic change in rod drop time over the last several cycles; and the monthly control rod movement surveillance will continue to show that rod is not bound.
The following information is attached:
- 1)
A marked up copy of the proposed revision to TS 4.7.1, 2) A discussion of the circumstances which have led to this request, 3) the safety basis for the request (includes the safety significance, potential consequences of. the proposed course of action, compensatory measures, and justification for the duration of the request),
- 4) The basis for the conclusion that this request does not have a potential adverse impact on the public health and safety and 5) The basis for the conclusion that this request does not involve adverse consequences to the environment.
Very Truly Yours, J. W. Hampton PJN xc:
L. A. Wiens, ONRR S. D. Ebneter Regional Administrator, Region II P. E. Harmon Senior Resident Inspector
DUKE POWER COMPANY OCONEE NUCLEAR STATION ATTACHMENT 1