ML20127B527
| ML20127B527 | |
| Person / Time | |
|---|---|
| Site: | Calvert Cliffs  |
| Issue date: | 01/05/1993 |
| From: | Office of Nuclear Reactor Regulation |
| To: | |
| Shared Package | |
| ML20127B504 | List: |
| References | |
| NUDOCS 9301120315 | |
| Download: ML20127B527 (2) | |
Text
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UNITED STATER o~g
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NUCLEAR REGULATORY COMMISSION y
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WASHINGTON, D. C. 20555
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SAFETY ELA10AT10fL8Y THE OFFICE OF NQC1 EAR REACTOR REGUt ATIO_h RELATED TO AMENDMENT NO.179 TO FACILITY OPERATING LICENSE NO. OPR-53 BJR AMENDMENT N0.156 TO FACILITY OPERATING LICENSE NO. DPR-O BALTIMORE GAS AND ELECTRIC COMPANY CALVERT E IFFS NVCLEAR P!)WER PLAhT, UNIT NOS. 1 AND 2 DEKET NOS, 50-317 N@ 50-318 1.0 INTR 000.Gll@
By letter dated Scptember 1,1992, the Baltimore Gas and Electric Company (the licensee) submitted a request for changes to the Calvert Cliffs Nuclear Power Plant, Unit Nos. I and.2, Technical Specifications (TS). The requested changes would revise TS 3.8.2.1, Onsite Power Distribution Systems AC Distribution-Operating, for Units 1 and 2, by adding additional requirements to the Limiting Condition for Operation (LCO). The LCO changes will require that all 480 volt emergency busses must be operable in Modes 1 through 4.
In addition, two safety-related motor control centers for each unit are addei to the 1tst of AC busses which must be operable.
2.0 EVALUATION The AC Distribution System is designed to supply power during normal operation and under accident conditions.
The four safety-related 480-volt busses and the two 480 volt Motor Control Centers (MCCs) supply power to the engineered safety features system. The engineered safety features electrical system uses the two channel concept to provide redundancy in anticipation of a single failure.
Emergency power for the 480-volt busses and MCCs is supplied by separate' emergency diesel generators. Operability of the 480-volt system is required to ensure the plant can mitigate a design basis accident.
The current TS is worded such that two 480-volt emergency busses on one unit could be inoperable without entering an Action Statement.
The licensee found that the original issue of custom TSs for Calvert Cliffs Unit I required the four safety-related 480-volt busses.and the two safety-related MCCs to be
- operable, in the conversion to Standard Technical Specification format, the requirements for the busses were changed such that--the LCO could be interpreted to allow two emergency 480-volt busses to be inoperable..The conversion also deleted the two safety-related MCCs from the LCO.
It has been the licensee's practice to maintain all four 480-volt busses operable in Modes-1 through 4 and to enter the Action Statements for any supported safety systems when a bus was declared inoperable.
Administrative controls are in place which require entering the Action Statement of TS 9301120315 930105" PDR ADOCK 05000317 P
i 1 i
-l 3.8.2-.1 if a 480-volt emergency bus is inoperable.
If one of the safety-related MCCs is inoperable, current practice is to review the affected equipment and enter the Action Statements appropriate for the inoperable equipment.
The requested charge will revise the TS to require entering the Action Statement of TS 3.8.2.1 i:!,en any 480-volt emergency bus or 480-volt MCC is inoperable.
The staff finds this change acceptable based on the fact that it provides additional requirements to ensure two independent and redundant power source trains will be available to supply the engineered safety features system during power operation.
3.0 STATE CONSULTATION
In accordance with the Comission's regulations, the Maryland State official was notified of the proposed issuance of the amendments. The State official had no comments.
4.0 MyIRONMENTAL C.Q!USIDERATION The amendments change a requirement with respect to installation or use of a; i
facility component located within the restricted area as defined in 10 CFR Part 20.
The NRC staff has determined that the amendments 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 previot sly issued a proposed finding that the amendments involve no significant hazaros consideration, and there has been no public comment on such finding (57-FR 45075). Accordingly, the amendments:
meet the eligibility criteria for categorical exclusion set-forth in 10 CFP..
51.22(c)(9).. Pursuant to 10 CFR Sl.22(b) no environmental impact statement or environmental assessment need be prepared in connection with the issuance _ of l
the amendments.
5.0 CONCLUSION
L 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 regul' tions, a
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:
C. Orsini L
Date: January'5, 1993 7
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