ML20155H684

Proposed Tech Specs Pages,Revising TS Bases Section 3/4.4.4, Relief Valves

ML20155H684
Person / Time
Site:	Wolf Creek
Issue date:	11/06/1998
From:	WOLF CREEK NUCLEAR OPERATING CORP.
To:
Shared Package
ML20155H681	List: ML20155H679 ML20155H684
References
NUDOCS 9811100236
Download: ML20155H684 (3)

Text

Attachment II to ET 98-0093 Page 2 of 2.

' REACTOR COOLANT SYSTEM BASES

' SAFETY VALVES (Continued)-

During operation, all pressurizer Code safety valves must be OPERABLE to prevent the RCS from being pressurized above its Safety Limit of 2735 psig.

The combined relief capacity of all of these valves is greater than the maximum surge rate resulting from a complete loss-of-load assuming no Reactor trip and also assuming no operation of the power-operated relief valves or steam dump valves.

Demonstration of the safety valves' lift settings will occur only during .

shutdown and will be performed in accordance with the provisions of Section XI of the ASME Boiler and Pressure Code.

Addition to the RCS of borated water with a concentration greater than or equal to the minimum required RWST concentration shall not be considered a positive reactivity change. Cooldown of the RCS for restoration of operability of a pressurizer code safety valve, with a negative moderator temperature coefficient, shall not be considered a positive reactivity change provided the RCS is borated to the COLD SHUTDOWN, xenon-free conditions per specification 3.1.1.1.

3/4.4.3 PRESSURIZER

.The 12-hour periodic surveillance is sufficient to ensure that the

- parameter is restored to within its limit following expected transient opera-tion. The maximum water volume also ensures that a steam bubble is formed and thus the RCS is not a hydraulically solid system. The requirement that a minimum number of pressurizer heaters be OPERABLE enhances the capability of the plant to control Reactor Coolant System pressure and establish natural circulation.

3/4.4.4 RELIEF VALVES The power-operated relief valves (PORVs) and steam bubble function to relieve RCS pressure during all design transients up to and including the design step load decrease with steam dump. Operation of the PORVs minimizes the undesirable opening of the spring-loaded pressurizer code safety valves.

Each PORV has a remote' operated block valve to provide a positive shutoff capability should a relief we become inoperable.

The PORVs are equipped with automatic actuation circuitry and manual control capability. Because no credit for automatic PORV operation is taken in the USAR analyses for MODE 1,2 and 3 transients, the PORVs are considered OPERABLE in either the manual or automatic mode. The automatic mode is the preferred configuration, as this provides pressure relieving capability without reliance on operator action.

Although a PORV may be designated inoperable, it may be able to be manually opened and closed, and therefore, be able to perform its pressure control function. PORVinoperability may be due to excessive seat leakage that does not prevent manual use and does not create the possibility for a small break LOCA.

Therefore, when a PORV is inoperable solely due to excessive seat leakage, the block valve may be closed; however, to allow continued operation, the Action requires power be maintained to the block valve to allow quick access to the associated PORV for pressure control.

WOLF CREEK - UNIT 1 B 3/4 4-2 Amendment No. 63, SG 9811100236 981106 7 PDR ADOCK 05000482 P. PDR

.i Attachment III to ET 98-0093 Page 1 of 2 ATTACHMENT III LIST OF COtedITMENTS l

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• Attachment III to ET 98-0093 Page 2 of 2 LIST OF COMMITMENTS l The following table identifies those actions committed to by Wolf Creek l Nuclear Operating Corporation (WCNOC) in this document. Any other statements in this submittal are provided for information purposes and are not considered to be commitments. Please direct questions regarding these commitments to Mr.

Michael J. Angus, Manager Licensing and Corrective Action at Wolf Creek Generating Station, (316) 364-4077.

Cote 4ITMENT Due Date/ Event None NA 1

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