ML20042F611
| ML20042F611 | |
| Person / Time | |
|---|---|
| Site: | Brunswick  |
| Issue date: | 05/02/1990 |
| From: | Cutter A CAROLINA POWER & LIGHT CO. |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| References | |
| REF-GTECI-A-47, REF-GTECI-SY, RTR-NUREG-1217, RTR-NUREG-1218, TASK-A-47, TASK-OR GL-89-19, NLS-90-104, TAC-74918, TAC-74919, NUDOCS 9005090152 | |
| Download: ML20042F611 (3) | |
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C8f00ftG POUWWF & Ligitt My m
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P.O. Bos,1551 e Raleigh. N c 27002 Sg NAY 81990 4
- A, B CUTTER SERIAL: NLS-90-104 vice Preskknt.
. Nuclear Services Department i
United States Nuclear Regulatory Commission l
ATTENTION: Document. Control' Desk
- Washington, DC-20555 4
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. BRUNSWICK STEAM ELECTRIC PLANT, UNIT NOS,1 AND 2
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DOCKET NOS. 50-325 & 50-324/ LICENSE NOS. DPR 71 & DPR 62
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REGPONSE TO NRC GENERIC LETTER 89-19 " REQUEST FOR ACTION
- i REIATED.TO RESOLUTION OF UNRESOLVED SAFETY ISSUE A-47, j
' SAFETY IMPLICATION OF CONTROL SYSTEMS IN LWR NUCLEAR J
- POWER' PIANTC '" (NRC TAC NOS. - 74918 AND 74919).
'Centlemen:
y On September 20,fl989, the NRC staff issued Generic Letter 89-19 which-7
- provided recommendations-concerning. automatic steam generator overfill.
mW protection'for all PWR plants and automatic reactor vessel overfill protection O$
Lfor7alf BWR plants.- The Generic Letter also recommended that plant procedures ni
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,and. technical. specifications for all plants should' include provisions to
- verify periodically the operability of the overfill protection and to assure 4
that automatic overfill protection is available to mitigate main feedwater-3 (MFW). overfeed. events during. reactor-power operation, JOn: February-16, 1990 the BWR Owners' Group (BWROG) subd tted a request to NRC to extend the March 20,11990 deadline for responding to the Generic Letter to-
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3May 4,.1990, in order to. allow individual BWR licensees time to review-the g
. generic response under preparation by the'BWROG, On March 6, 1990, the.BWROG 4
l received. notification from NRC that the response deadline had been extended g
accordingly. The BWROG generic response to Generic Letter 89-19 was subsequently submitted to NRC on April 2, 1990, m
Carolina Power & Light Company (CP&L) participated in the BWROG effort to L
. prepare the generic. response on this issue and the Brunswick Steam Electric b
Plant,.: Unit Nos.1 & 2. (BSEP) is one of the participating BWROG nuclear power plants listed iniTable 1 of the BWR00 response to the Generic Letter.
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. has reviewed the BWROG. response to Generic Letter 89 19 and agrees with the BWROG conclusion that the plants addressed by the report provide adequate and reliable automatic' overfill protection consistent with the NRC requirements h*
for closure'of Unresolved' Safety Issue A-47, As noted'in the BWR00 generic response, the NRC has recognized in NUREG-1217.
. and NUREG-1218 that the safety benefits gained by providing additional protection system redundancy and. independence from existing MFW control system i
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5 equipment is not s ignificant, and that related modifications costing in excess of $100,000- are noc cost-bereficial, In order-for BSEP to fully comply with 3
Generic Letterf 89-19 rettamendations, substantial equipment and wiring rearrangement,=and additional reactor pressure vessel-(RPV) overfill' prote2 tion trip channels, sensors, logic devices, wires, and cabling, and even new racks and panels to house this equipment, would have to be provided.
CP&L estimates that for BSEP, the cost associated with the' design, purchase, and' finstallation of additional'RPV overfill protection and MFW control system logic channel devices; and the separation modifications necessary to fully
. satisfy'the Generic Letter recommendations would be substantially higher than the $100,000 amount discussed in NUREG-1217 and NURG-1218.
As-noted by the BWROG in their generic response, a review of BWR plant
- operating experience'did not-identify any MFW system RPV overfill events subsequent to:the installation of an automatic RPV overfill protection system.
In addition, the BWROG did not identify as a result of records reviews, the occurrence of any BWR common mode MFW control system failures that might have resulted in RPV overfill.
Consequently, CP&L concludes that the existing MFW Control System and Overfill Protection System provides adequate RPV overfill protection for BSEP and that any safety benefits (i.e., RPV overfill risk-reduction) provided by modifying these systems in full accordance with' Generic Letter 89-19 recommendations would not be significant enough to warrant the F
substantial additional related cost.
A description of the existing-BSEP overfill protection system configuration, BSEP operating procedures, and operator training. relative to Generic Letter 89 19 recommendations.are provided as follows.
.The overfill protection system for BSEP has a two-out-of-three initiating i
logic which is commercial grade, but uses one of the three channele for both control and protection.
This design is encompassed by Group I of the GE BWR plants discussed in Enclosure 2 to the Generic Letter, and is encompassed by the Group'A RPV overfill protection system configuration described in Table 2 of the BWROG generic response.
The BSEP MFW Contrcl System and Overfill Protection System are not ssfety-related systems.- CP&L has reviewed the design for BSEP and found that, similar to most non-safety-related systems installed in BWRs, the existing configuration consists of three separate power. circuits to one panel, which houses: independent power supplies for each level transmitter.
Due o the commercial grade nature of the system when installed, divisionalization of power supply and cable routing was not required.
BSEP presently has approved plant procedures to calibrate the MFW Control o
System and overfill Protection System instrumentation that initiate L
protective actions. These procedures include provisions to periodically
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verify the operability of the MFW Overfill Protection System and to ensuro that the automatic overfill protection is operable during reactor power operation. Periodic maintenance procedures are carried out to verify the calibration and accuracy of such instrumentation.
In addition, BSEP l
presently does have operating procedures (OP)and abnormal operating
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LNLS.90-104'/ Page 3-e procedures (AOP).for training operators to select either of the two redundant
' Level? Transmitters A or B in case of failure of either of'the two transmitters. These ops and AOPs also ensure that the operators can mitigate
-reactor vessel overfill events that may occur via the condensate booster pumps during reduced pressure operation of the system. BSEP personnel are reviewing the.BSEP emergency operating procedurea (EOP) to determine if revisions to the E0Ps are necessary to preclude reactor vessel overfill during abnormal conditions.-
Since BSEP already has plant procedures for the MFW Control System and the
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Overfill Protection System which provide adequate guidance for the. operation
-and maintenance of.these systems, the Company believes that Technical-Specification requirements for these systems at BSFP are unnecessary at: this time.
In addition,~ adequate guidance is not currently available to licensees-on what the Staff considers acceptable.concerning-limiting conditions for operation, action requirements, or surveillance requirements for MFW Control Systems and Overfill Protection. Systems. The Company believes that any l
Technical Specification. requirements for these systems should be ' developed, reviewed, and approved through the development process for the Improved Standard Technical Specifications currently being. prepared by the four Owners' Croups and the NRC.
Yoursveryty f
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/A A. B Cutter s
JCP/jp A.'B Cutter,<having been first duly sworn, did depose and say that the information contained herein is true and correct to the best of his p
information, knowledge and belief; and the sources of his'information are P
- officers, employees, contractors, and agents of Carolina Power & Light Company.
- 5. Rowd
... as V ) Notary (Seal) l 4
My commission expires: 7 /12/9 4 p e s e e,,,,,
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.Mr. S. D. Ebneter i
Mr. N. B. 1"
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Mr. W. H. Ruland
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