ML20092M107

Proposed TS 3.3.2,Table 3.3-3, ESFAS Instrumentation, Correcting Action Ref for Functional Unit 8.b Re Automatic Switchover to Containment Sump/Rwst Level low-low

ML20092M107
Person / Time
Site:	Seabrook
Issue date:	09/22/1995
From:	NORTH ATLANTIC ENERGY SERVICE CORP. (NAESCO)
To:
Shared Package
ML20092M099	List: ML20092M097 ML20092M101 ML20092M107
References
NUDOCS 9509290017
Download: ML20092M107 (5)

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@ TABLE 3.3-3 (Continued)

ENGINEEREbSAFETYFEATURESACTUATIONSYSTEMINSTRUMENTATION .

MINIMUM c TOTAL NO. CHANNELS CHANNELS APPLICABLE .

3 FUNCTIONAL UNIT OF CHANNELS TO TRIP OPERABLE MODES ACTION

b. RWST Level--Low-Low 4 2 3 1, 2, 3, 4 6 Coincident With:

Safety Injection See Item 1. above for all Safety Injection initiating functions and requirements.

9. Loss of Power (Start-Emergency Feedwater) w a. 4.16 kV Bus E5 and E6- 2/ bus 2/ bus 1/ bus 1, 2, 3, 4 14 1 Loss of Voltage [

b. 4.16 kV Bus E5 and E6-n.o . Degraded Voltage 2/ bus 2/ bus 1/ bus 1, 2, 3, 4 14 ou Coincident with SI l

'S See Item 1. above for all Safety Injection initiating functions y and requirements.

oo 03 10. Engineered Safety Features

" Actuation System Interlocks OD E$ a. Pressurizer Pressure, 3 2 2 1, 2, 3 19 o8$ P-ll gaan g"0 o.

b. Reactor Trip, P-4 2 2 2 1, 2, 3 21

[ c. Steam Generator Water 4/stm. gen. 2/stm. gen. 3/sta gen. 1, 2, 3 18

• Level, P-14 5

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4 Ill, Retyne of Pronaaed Chances See attached retype of proposed changes to Technical Specifications. The attached retype reflects

the currently issued version of Technical Specifications. Pending Technical Specification changes or Technical Specification changes issued subsequent to this suhmittal are not reflected in the enclosed retype. The enclosed retype should be checked for continuity with Technical

Specifications prior to issuance.

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g TABLE 3.3-3 (Continued) , ,

E ENGINEERED SAFETY FEATURES ACTUATION SYSTEM INSTRUMENTATION 8

MINIMUM TOTAL NO. CHANNELS CHANNELS APPLICABLE E FUNCTIONAL UNIT OF CHANNELS TO TRIP OPERABLE MODES ACTION w

~ b. RWST Level--Low-Low 4 2 3 1.2.3.4 15 Coincident With:

Safety Injection See Item 1. above for all Safety Injection initiating functions and requirements.

9. Loss of Power (Start Emergency Feedwater)

a. 6 B E5 and E6- 2/ bus 2/ bus 1/ bus 1.2.3.4 14 Y b. 4.16 kV Bus E5 and E6-3 Degraded Voltage 2/ bus 2/ bus 1/ bus 1.2.3.4 14 Coincident with SI See Item 1 above for all Safety Injection initiating functions and requirements.

10. Engineered Safety Features Actuation System Interlocks

a. Pressurizer Pressure. 3 2 2 1. 2. 3 19 i P-11 l E i

b. Reactor Trip. P-4 2 2 2 1. 2. 3 21 g c. Steam Generator Water 4/stm. gen. 2/stm. gen. 3/stm. gen. 1. 2. 3 18 r z Level. P-14 y l

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]% D:icrail== tion of Signincent Ha>=nis for Pro =ana,I Ch==ges 1

1. The proposed changes do not involve a sigmficant increase in the probability or consequences of i an accidentpreviously evaluated. l The changes proposed in License Amendment Request (LAR) 95-07 will result in an inoperable Engineered Safety Features Actuation Systems (ESFAS) protective channel being placed in the

. bypassed condition rather than the tripped condition. The ESFAS Refueling Water Storage Tank

(RWST) Level Low-Low protective function is not an accident initiator and placing an inoperable 4

. channel in bypass will reduce the probability of premature opening of the containment building spray (CBS) sump isolation valves. When a channel is determined to be inoperable, the bistable j would be bypassed per the amended Technical Specification Action Statement.

LAR 95-07 is revising a Technical Specification Action Statement reference to eliminate the

< possibility ofincreasing the consequences of an accident previously evaluated in the Updated Final 1

Safety Analysis Report (UFSAR). Specifically, by changing the requirement from placing an inoperable RWST Level Low-Low channel in trip to placing it in bypass, eliminates the scenario where the consequences of a Loss of Coolant Accident (LOCA) can be increased by premature opening of the CBS sump isolation valves as described in Seabrook Station Licensee Event Report 1 (LER)93-002, Supplement 1.

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2. The proposed changes do not create the possibility ofa new or diferent kind of accidentfrom any

accidentpreviously evaluated.

i. The changes proposed in LAR 95-07 affect the state of an inoperable RWST Level Low-Low channel. With the inoperable RWST Level Low Low channel in bypass, the possibility of premature opening of the CBS sump isolation valves due to the failure of a RWST level channel is eliminated. The function and failure modes of the RWST level channels have not changed. The l minimum RWST level channels operable requirement is met.

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3. Theproposedchanges do not result in a sigmficant reduction in the margin ofsafety.

The margin of safety as defined in the Basis for Technical Specification 3.3.2 is based on the i minimum channels operable requirement for ESFAS instrumentation and provides unit protection in the event of any of the analyzed accidents. Placing a failed channel in the tripped condition could result in a premature opening of the CBS sump isolation valves, prior to the injection of the j minimum volume from the RWST Placing the inoperable channel in bypass results in a two-cut-4 of-three logic configuration, which satisfies the requirement to allow another failure without disabling actuation of the switchover when required by maintaining the minimum channels j

. operable requirement of three. j l

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V.; Prew Schedule for I.leense Amendment Issuance and Effective =a== l North Atlantic requests NRC review of License Amendment Request 95-07 and issuance of a )

license amendment having immediate effectiveness by January 1,1995.

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VI. EityirDAmentallmpact Assiment North Atlantic has reviewed the proposed license amendment against the criteria of 10CFR51.22 for environmental considerations. The proposed changes do not involve a signincant hazards consideration, nor increase the types and amounts of effluent that may be released offsite, nor signincantly increase individual or cumulative occupational radiation exposures. Based on the foregoing, North Atlantic concludes that the proposed change meets the criteria delineated in 10CFR51.22(c)(9) for a categorical exclusion from the requirements for an Environmental Impact Statement.

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