ML20133G629
| ML20133G629 | |
| Person / Time | |
|---|---|
| Site: | Brunswick  |
| Issue date: | 10/10/1985 |
| From: | Cutter A CAROLINA POWER & LIGHT CO. |
| To: | Harold Denton Office of Nuclear Reactor Regulation |
| References | |
| NLS-85-349, NUDOCS 8510160057 | |
| Download: ML20133G629 (2) | |
Text
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CD&L Carolina P wer & LigM Company I 1 01995 SERIAL: NLS-35-349 Mr. Harold R. DentonI Director Office of Nuclear Reactor Regulation United States Nuclear Regulatory Commission Washington, DC 20555 BRUNSWICK STEAM ELECTRIC PLANT, UNIT NOS.1 AND 2 DOCKET NOS. 50-325 & 50-324/ LICENSE NOS. DPR-71 & DPR-62 ANTICIPATED TRANSIENTS WITHOUT SCRAM (ATWS)
Dear Mr. Denton:
Carolina Power & Light Company hereby submits the information required by 10 CFR 50.62(d) regarding the implementation of ATWS mitigating systems at the Brunswick Steam Electric Plant units.
As amended by the final rule on ATWS,10 CFR 50.62 requires the installation of an l
Alternate Rod Injection (ARI) system, a Standby Liquid Control System (SLCS) of a l
specified capacity, and an automatic recirculating pump trip system in all boiling water reactors.
ALTERNATE ROD INJECTION SYSTEM An Alternate Rod Injection System will be installed in each of the Brunswick units. The ARI system will utilize redundant scram air header exhaust valves and will, to the extent practical, utilize existing Reactor Pump Trip (RPT) logic hardware and level / pressure sensors. This system will be independent from sensor output to final actuation device from the existing reactor protection system. Since the engineering design for the ARI system is not yet complete, more detailed information is not available at this time.
When the final engineering analysis is complete, a more detailed description of the ARI system will be submitted.
STANDBY LIQUID CONTROL SYSTEM The existing SLCS at each facility includes two positive displacement pumps connected i
in parallel. The SLCS pump motor control logic is presently configured so that only one of the two pumps may be operated at any time. Each SLCS pump is capable of delivering approximately 43 gallons per minute of sodium pentaborate solution to the reactor vessel upon manual operation of a control switch on the RTGB.
Carolina Power & Light Company is evaluating several options by which the equivalent injection rate requirement can be met. One option being considered is the use of enriched sodium pentaborate which would meet the required equivalent injection rate with the present pumps and logic system. Another option being considered is operation h0[DO DR 90 l
P i
411 Fayettevole Street
- P. O Box 1s51
- Ra e gn. N C 27602 I Q 1
9
Mr. Harold R. Denton Page 2
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of both pumps simultaneously to satisfy the equivalent injection rate criteria specified in 10 CFR 50.62(cX4). Carolina Power & Light Company will inform the NRC of the option selected to meet the requirements of 10 CFR 50.62 and will proceed with implementation of the selected option so as to conform with the schedule provided
- below, j
RECIRCULATING PUMP TRIP SYSTEM Both units at Brunswick have systems which automatically trip the recirculating pumps in conditions indicative of an ATWS. Therefore, no additional modifications are required to satisfy this requirement of 10 CFR 50.62.
IMPLEMENTATION SCHEDULES The ATWS mitigating systems modifications at the Brunswick facilities will be implemented by completion of Refueling Outage 5 for Unit I and Refueling Outage 7 for Unit 2. These outages are scheduled to begin in May 1987 and March 1988, respectively.
3 i
These schedules are in conformance with the prescribed "second refueling outage af ter i
July 26,1984" specified in 10 CFR 50.62(d).
Carolina Power & Light Company will submit detailed information on the ARI and SLCS by July 1,1986. We will continue to apprise the NRR Project Manager concerning our progress on the detailed design information.
If you have any questions, please contact Mr. S. R. Zimmerman at (919) 836-6242.
t Your cry tru '
[
A. B. Cutter - Vice P 'sident Nuclear Engineering Licensing ABC/SDC/ccc (1964SDC) cc:
Mr. W. H. Ruland (NRC-BNP)
Dr. J. Nelson Grace (NRC-Ril)
Mr. M. Grotenhuis (NRC) 1 3
}
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