ML20091B231
| ML20091B231 | |
| Person / Time | |
|---|---|
| Site: | Beaver Valley |
| Issue date: | 03/25/1992 |
| From: | Office of Nuclear Reactor Regulation |
| To: | |
| Shared Package | |
| ML20091B224 | List: |
| References | |
| NUDOCS 9203310187 | |
| Download: ML20091B231 (3) | |
Text
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'r' UNITED STATES 8\\
NUCLEAR REGUL ATORY COMMISSION
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SAFETY EVALVATION BY THE OFFICE OFjtyCLEAR REACTOR REGVJ,ATION RELATED TO AMENpMENT N0. 164 TO FACILITY OPERATING LICENSE N0. DPR-66 6ffD.jlfi[NDMENT NQ. 44 TO FACILITY OPERATING LICENSE NO.
NPF-73 DV0VESNE LIGHT COMPANY OHIO EDIS0N COMPANY PENNSYLVANIA PORER COMPANY
_TJ1E CLEVELAND ELECTRIC ILLUMINATING COMPANY THE TOLEDO EDISON COMPAt{1 BEAVER VAll1LE0WER STATION. _l!f]IT NOS. 1 AND 2 DOCKET NOS. 50-334 AND 50-412 1.0 INTRODUCTIOS By letter dated December 21, 1989, Duquesne Light Company (DLC/the licensee) proposed certain revisions to the Beaver Valley Power Station, Units I and 2 Appendix A Technical Specifications relating to the accumulators in the emergency core cooling systems (ECCS),
Specifically, DLC has proposed to delete Surveillance Requirement 4.5.1.d for both Units 1 and 2, and to correct a typographical error in Surveillance Requirement 4.5.1.c for Unit 1 only.
Surveillance Requirement 4.5.1.d requires verification that the accumulator
'i isolation valves open automatically upon receipt of a safety injection signal and when the reactor coolant system (RCS) pressure exceeds the P-11 interlock setpoint.
This surveillance test is required at least every 18 mcnths.
2.0 DISCUSSION Emergency core cooling in the event of a loss-of-coolant accident (LOCA) is provided by the emergency core cooling system (ECCS).
Included among the principal components of the ECCS providing emergency core cooling immediately following a LOCA are the three accumulators. The accumulators are pressure vessels partiaily filled with borated water and pressurized with nitrogen.
In the event the reactor coolant system pressure (RCS) falls below the gas pressure in the accumulators, the water is forced into the reactor coolant system.
9203310107 920325 PDR ADOCK 05000334 P
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Two check valves in series in each accumulator discharge line prevent backflow from the RCS during operation, and a motor-operated isolation valve in each l
discharge line can be closed to prevent unwanted accumulator discharge when the RCS pressure is intentionally reduced during startup or sh.itdown.
To assure that the accumulator isolation valves are not closed at a time when ECCS may be required, the accumulator isolation valves receive an "open" signal upon receipt of a safety injection signal or when the pressurizer i
pressure exceeds 2000 psig.
The isolation valves have redundant position indicating lights in the control l
room.
For Unit 1, position indication is taken from independent limit switches in the isolation valve motor-operator. At Unit 2, limit witches in the isolation valve motor-operator and on the valve stem provide position indication.
For both units, an annunciator will al. arm when the safety injection block is removed should a valve not be fully oren. The alarm is repeated at approximately 1-hour intervals until the valve is properly positioned.
DLC has stated that Surveillance Requirement 4.5.1.d.1 is performed for each isolation valve individually in succession during the stat tup sequence. The RCS pressure is increased above the 2000 psig setpoint to demonstrate that the l
safety injection signal block is removed automatically and the isolation valve under test opens.
The RCS pressure.is then lowered, the safety _ injection signal block re-instituted, and the next isolation valve to be tested is closed in order to repeat the test. Thus, the RCS pressure is cycled between l
about 1000 psig and 2000 psig three times to perform the surveillance requirement. The operator is required to take manual action on each pressure decrease to re-institute the safety injection block and to close the isolation valve to prevent inadvertent safety injection.
3.0 fVAl.UATION Limiting Condition for Operation 3.5.1 requires each accumulator to be operable in Modes 1 and 2 and in Mode 3 when the pressurizer pressure exceeds 1000 psig. To be operable requires, among other conditions, the accumulator i
l isolation valves to be open.
Surveillance Requirement 4.5.1.a requires verification at least once every 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> that the isolation. valves are open and that no position alarms are l
present. Surveillance Requirement 4.5.1.c requires that each accumulator be l
demonstrated operable by verifying at least every 31 days that power to the l
isolation valve motor-operator control circuits is *.'emoved.
DLC has stated that the isolation valve motor-operators are energized only momentarily during i
l startup at approximately 1000 psig RCS pressure to open the valves and are then deenergized.
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During shutdown, the motor-operitors are again momentarily energized to close the valves at approximately 1000 psig in the RCS.
Surveillance Requirement 4.5.1.3 requires verification that the valves are closed and deenergized when the RCS pressure is reduced to 1000 1 100 psig.
Since the isolation valves are open with power removed during plant operation, and required periodic surveillances verify that power to the valve motor-operators is removed, the valves are open, and no position alarms are present, the possibility of inadvertent closure of the isolation valves is eliminated.
Because the valves are energized for only brief intervals to change valve position during startup or shutdown, the automatic actuation features to assure the valves will open when required serve no useful function. Thus, we conclude that periodic testing per Surveillance Requirement 4.5.1.d is not required, and deletion of the surveillance requirement is acceptable.
DLC also proposes to chenge be to by to correct a typographical error in Surveillance Requirement '4.5.1.c.
This is acceptable.
3.0 ENVIRONMENIM CONSIDERATION The amendment changes surveillance requirements. The NRC staff has determined that the amendments irvolve no significant increase in the amounts, and no significant change in the types, of any effluents that $ay 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 (56 FR 4269). Accordingly, the amendments meet the eligibility criteria for categorical e'xclusion 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.
4.0 STATE CONSULTATION
in accordance with the Commission's regulations, the pennsylvania State official was notified of the proposed issuance of the amendments. The State official had no comments.
5.0 @ Ej,USION The Commission has concluded, based on the considerations discussed above, that:
(1) there is reason 6ble assurance that the health and safety of the public will not be endangered by operation in the proposed manner, (2) such 4
activities will be conducted in compliance with the Commission's regulations, a,d (3) the issuance of the amendments will not be inimical to the common oafense and security or to the health and safety of the public.
Principal Contributor:
Albert W. De Agazio Oate:
%rch 25,1992
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