ML20114B650
| ML20114B650 | |
| Person / Time | |
|---|---|
| Site: | Catawba  |
| Issue date: | 08/17/1992 |
| From: | NRC |
| To: | |
| Shared Package | |
| ML20114B646 | List: |
| References | |
| NUDOCS 9208310033 | |
| Download: ML20114B650 (3) | |
Text
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UNITED STATES n
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i NUCLEAR REGULATORY COMMISSION
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WASHINGTON D.C. M66 o
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SAFETY EVALVAT10ti BY THE OFFICF 0F HUCLEAR REACTOR REGULAJ1QH l
BDjTED TO AMENDMENT NO.100TO FACII ITY QPERATING 11 CENSE NPF-35 AND AMENDMENT NO 98 TO FACillTY OPERATING LLCQQE NPF-52
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DUKE POWER COMpAN). ET AL CATAWBA NUCLEAR STAUON. UNITS 1 AND 2 QQCKET NOS. 50-413 AND 50-414 i
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1.0 INTRODUCTION
1 By letter dated May 14, 1992, as supplemented August 5, 1992, the Duke Power
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Company (the licensee) submitted a request for changes to the Catawba Nuclear Station, Units 1 and 2, Technical Specifications (TS).
The requested changes would revise TS Surveillance Requirement 4.8.2.1.1.d which will prmit the l
service test of battery 2EBD to be conducted during power operation on a one-time basis prior to the expiration of the current surveillance interval grace period on August 24, 1992.
The initial application requested a complete deletion of the testing-during-shutdown requirement of TS 4.8.1.1.d for all four divisions of batteries on each plant.
The scope of the initial application was reduced substantially in the August 5, 1992, submittal to addres; deletion of the testing-during-shutdown requirement for only one battery oivision in Unit 2 on a one-time baris.
The August 5, 1992, letter provided clarifying information that did not change the initial proposed no significant hazards consideratior determir,atien.
During the electrical distribution system functional inspection (EDSFI), the team from the Special Inspection Branch of DRIS, NRR, isst.ed a violation because Catawba had been conducting the 18-month battery service test while the unit was operating instead of while the unit was shutdown, as required by i
Technical Specification Surveillance Requirement 4.8.2.1.1.d.
The team also raised a related issue that the smaller 825 ampere-hour vital battery at Catawba may not be capable of supplying the loads of two emergency de buses simultaneously while the larger (1200 ampere-hour) battery i:: out for testing during power operation.
2.0 EVALUATION On each unit, the batteries on Channels A and D are rated for 1200 ampere-hours and those on Channels B and C are rated for 825 ampere-hours.
The licensee states that the 1200 ampere-hour batteries have adequate capacity to supply the loads of one load group and tlie loads ut another load group for two hours and that the 825 ampere-hour batteries have adequate capacity to tupply i
the loads of one load group and the loads of another load gro;.p for a minimum of one hour.
During normal operation, the batteries are floated on the dc 9200310o33 9pos17 PDR
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- I distribution centers and are available to assume the loads without interruption upon loss of a battery charger or ac power source.
Each battery charger is capable of supplying the steady-state loads of its load group while charging its associated battery. A spare battery charger is also provided to serve as a backup for any of the normal battery chargers.
When a service test is being performed on a particular battery, the battery and associated battery charger are removed from service, the de distribution centers are cross-tied, and the standby charger is connected to the affected distribution center.
Therefore, both a battery and two battery chargers remain avoilable to supply the cross-tied channels during the test.
Fr' lowing the EDSF1, the licensee has reassessed the calculation for sizing i
the dc batteries.
The preliminary assessments have identified specific l
conservatism used in sizing the dc batteries.
The conservatism used were as follows:
1.
Only two periods were established for the one-hour duty cycle (first minute - 1st period; last 59 minutes - 2nd period).
2.
Both non-continuous and momentary loads were assum.4 to be continuous for each respective period of the duty c :1e; and a
3.
Loads were conservatively estimated.
I We have reviewed the list of the specific load revisions, the respective bases for load revision, and the revised load requirements for each period of the 825 ampere-hour battery duty cycle. We have also reviewed the total loads for two channels being fed fraa a single 825 ampere-hour battery.
The l
licensee's submittal stated that the adjusted battery discharge current is approximab.ly 316 amperes for the first minute, 200 amperes for the 1-10 minute period, 198.5 amperas for the 10-20 minuto period, and 188 amperes for the 20-60 minute period.
The corresponding battery terminal end voltages are 112.7 Vde, 115.1 Vde, 114.5 Vdc and 113.3 Vdc, respectively.
Based on this assessment, the licensee concluded that the 825 ampere-hour oattery was adequate to handle the loads of both channels with a 40% margin.
We have reviewed the licensee's submittal and have found that the preliminary i
assessment of the de system indicates that the 825 ampere-hour battery has l
adequate capacity to carry the loads with the two channels cross-tied.
Based on the above evaluation, we believe that Duke Power Company has provided adequate basis for the Surveillance Requirement 4.8.2.1.1.d to be performed for battery 2EBD during power operation on a-one-time basis, and, accordingly, this Technical Specification change is approved.
3.0 STATE CONSVLTATION l
l In accordance with the Commission's regulations, the South Carolina State official was notified of the proposed issuance of the amendments.
The State official hr.1 no comments.
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4.0 ENVIRONMENTAL CONSIDERATION
The amendments change surveillance requirements.
The NRC staff has determined that the amer.dments involve no significant increase in the amounts, and no significant change in the types, of any effluents that may be released offsite, and that there is no significant increase in individual or cumulative occupational radiation exposure.
The Commission has previously issued a proposed finding that the amendments involve no significant hazards consideration, and there has been no public comment on such finding (57 FR 22262 dated May 27, 1992). Accordingly, the amendments meet the eligibility criteria for categorical exclusion set forth in 10 CFR 51.22(c)(9).
Pursuant to 10 CFR 51.22(b), no environmental impact statement or environmental assessment need be prepared in connection with the issuance of the amendments.
5.0 CONCI.USION The Commission has concluded, based on the considerations discussed above, that:
(1) there is reasonable assurance that the health and safety of the public will not be endangered by operation in the proposed manner, (2) such activities will be conducted in compliance with the Commission's regulations, and (3) the issuance of the amendments will not be inimical to the common defense and security or to the health and safety of the public.
Principal Contributor: N. K. Trehan, ESB Date:
August 17, 1992 c
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