ML20100C102

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Proposed Tech Specs Table 3.3.3-1 Re Emergency Core Cooling Sys Actuation Instrumentation
ML20100C102
Person / Time
Site: Nine Mile Point Constellation icon.png
Issue date: 01/25/1996
From:
NIAGARA MOHAWK POWER CORP.
To:
Shared Package
ML20100C092 List:
References
NUDOCS 9601300082
Download: ML20100C102 (7)
v • d • e


Text

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ATTACHMENT A NIAGARA MOHAWK POWER CORPORATION LICENSE NO. NPF-69 DOCKET NO. 50 410 Proposed Channe to Technical Snecifications The existing pages 3/4 3-33 and 3/4 3-44 will be replaced with the attached revised pages. These pages have been retyped in their entirety with marginal markings to indicate changes to the text.

1 9601300082 960125 PDR ADOCK 05000410 P PDR ,

, TABLE 3.3.3-1 (C:ntinued)

EMERGENCY CORE COOLING SYSTEM ACTUATION INSTRUMENTATlON TABLE NOTATIONS

  • When the system is required to be OPERABLE per Specification 3.5.2 or 3.5.3.
    • Required when the associated diesel generator is required to be OPERABLE.

(a) When a channel is placed in an inoperable status solely for performance of required surveillances, entry into associated Conditions and required ACTIONS may be delayed for up to 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> provided the associated function or the redundant function maintains ECCS initiation capability.

(b) Also actuates the associated division diesel generator.

(c) Not required to be OPERABLE when reactor steam dome pressure is less than or equal to 100 psig.

(d) The injection function of Drywell Pressure High and Manual Initiation is not required to be OPERABLE with indicated reactor vessel water level on the wide range instrument greater than level 8 setpoint coincident with the vessel pressure less than 600 psig because of hot calibration / cold operation level error.

(e) Provides signal to close HPCS pump injection valve only.

(f) Provides signal to HPCS pump suction valves only. l ACTION ACTION 30 - With the number of OPERABLE channels less than required by the Minimum I OPERABLE Channels per Trip Function requirement: I

a. With one channel inoperable, place the inoperable channel in the tripped condition within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />
  • or declare the associated sysum ;

inoperable. j i

b. With more than one channel inoperable, declare the associated system inoperable.

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ACTION 31 - With the number of OPERABLE channels less than required by the Minimum OPERABLE Channels per Trip Function requirement, r!?ce the inoperable channelin the tripped condition within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />; restore the inoperable channel to OPERABLE status within 7 days or declare the associated system inoperable.

  • The provisions of Specification 3.0.4 are not applicable.

l NINE MILE POINT - UNIT 2 3/4 3-33 AMENDMENT NO. N

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. TABLE 4.3.3.1-1 (C$ntinued) j l

EMERGENCY CORE COOLING SYSTEM ACTUATION INSTRUMENTATION SURVEILLANCE REQUIREMENTS l TABLE NOTATIONS ,

  • When the system is required to be OPERABLE per Specification 3.5.2.
    • Not required to be OPERABLE when reactor steam dome pressure is less than or equal to l 100 psig.

t Required when the associated diesel generator is required to be OPERABLE.

l (a) Manual initiation switches shall be tested at least once per 18 months during shutdown.

All other circuitry associated with manualinitiation shall receive a CHANNEL FUNCTIONAL TEST at least once per 92 days as part of the circuitry required to be tested for automatic system actuation.

(b) The injection function of Drywell Pressure - High and Manual Initiation is not required to be OPERABLE with indicated reactor vessel water level on the wide range instrument greater than Level 8 setpoint coincident with the vessel pressure less than 600 psig due to the hot i calibration / cold operation level error.

(c) Perform the calibration procedure for the Trip Setpoint et least once per 92 days.

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l NINE MILE POINT - UNIT 2 3/4 3-44 AMENDMENT NO. //

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l ATTACHMENTB NIAGARA MOHAWK POWER CORPORATION LICENSE NO. NPF-69  !

DOCKET NO. 50 410 l Suncorting Information and no Sinnificant Hazards Consideration Analypig .i INTRODUCTION

-l The loss of voltage and degraded voltage instruments function to assure a reliable source  !

. of electrical power to the divisional emergency switchydars during abnormal offsite power l conditions. Specifically, the Loss of Power instrumentation initiates an automatic j sequence to remove loads from the emergency bus and another automatic sequence to 1' start the diesel generator. Once power is restored to the emergency switchgear from the diesel generator, loads essential to operation of the diesel (i.e., service water pumps) are  :

automatically reconnected to the emergency switchgear. Ultimately, it is the associated '

diesel generator that supplies the reliable electrical power when offsite power is not i available; therefore, without an OPERABLE diesel generator, the Loss of Power i instrumentation cannot perform this function. Removing the Loss of Power relays from f service for calibration during Operational Conditions 4 and 5 will not prevent any other ESF functions. The Loss of Power relays do provide a redundant equipment protection function (i.e., undervoltage protection) for various loads on the emergency buses, however, this equipment protective function is not required for OPERABILITY of these loads. The proposed change will tie the required OPERABILITY of the Loss of Power instrumentation ,

directly to the OPERABILITY requirement of the associated diesel generator. This change i will clarify when the Loss of Power instruments are required to be OPERABLE in Operational Conditions 4 and 5.

The Channal Calibration Surveillance test requires that all three loss of voltage or all three degraded vcitage relays for a given Divisional 4.16 kv electrical bus be removed from service simultaneously. The Channel Calibration takes approximately three hours to perform and requires the associated diesel generator be declared inoperable. If any ESF equipment powered by this Division was required to be OPERABLE, the loss of voltage and degraded voltage relays would be required to be tripped within one hour (ACTION 39 of Technical Specifications). If the relays are placed in the tripped condition, the Channel Calibration cannot be performed. In the past, the Channel Calibration for the Loss of Power relays was only performed when the core was completely offloaded, and the ESF functions were not required to be OPERABLE.

During refueling outage RF05, Niagara Mohawk intends to perform a fuel shuffle versus a complete core offload. Without completely offloading the core, the Channel Calibration for the Loss of Power instrumentation would be very difficult to schedule because of the overly restrictive Applicability footnote in Operational Conditions 4 and 5. The proposed change would allow completion of maintenance and surveillance testing on the Loss of Page 1 of 4

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Power instruments when the associated diesel generator is out of service for maintenance  !

' and testing.  !

I DESCRIPTION OF CURRENT AND PROPOSED TECHNICAL SPECIFICATIONS  !

Current version of double-asterisk footnote to Table 3.3.3-1 and dagger footnote to Table .

4.3.3.1-1:  !

Required when ESF equipment is required to be OPERABLE.

Proposed version of double-asterisk footnote to Table 3.3.3-1 and dagger footnote to .

Table 4.3.3.1  ;

Required when the associated diesel generator is required to be OPERABLE. l l

EVALUATION The Loss of Power instrumentation is required to automatically initiate diesel generator start and load. The diesel generator then supplies reliable power for the Engineered Safety Features (ESF) to function during any accident with a loss of offsite power. The Loss of  ;

Power instruments initiate the start and load sequence of the associated diesel generator. ,

when the offsite power supply to the Division I,11, or ill electrical buses is insufficient to ,

supply the electricalloads. The diesel generators are then capable of supplying electrical power to Emergency Core Cooling Systems (ECCS) and other ESF loads. The initiation and l continued operation of ECCS ensures that the plant will maintain safe shutdown a conditions. The Loss of Power instrumentation assures the diesel generator start and load I sequence initiates on a loss of voltage and degraded voltage on the associated Divisional 4.16 kv electrical bus. Removing the Loss of Power instruments from service has a direct '

effect on the safety function of the diesel generators, but would not prevent any other ESF functions. Accordingly, the proposed change will continue to require the Loss of Power instruments to be OPERABLE in Operational Conditions 4 and 5, but only when the ,

associated diesr,I generator is required to be OPERABLE. The Loss of Power relays do '

provide a redundant eouipment protection function for various loads on the emergency buses, however, this equipment protective function is not required for OPERABILITY of these loads. The Loss of Power relays will continue to support emergency switchgear operability and reliability. This revision to the Technical Specifications will clarify the OPERABILITY requirements for the Loss of Power instruments by specifying the associated diesel generator as the required ESF equipment.

CONCLUSIONS The Loss of Power instrumentation directly affects the safety function of diesel generators on a loss of offsite power. Remova! of the Loss of Power instrumentation from service will not prevent any other ESF function. During Operational Conditions 4 and 5, the i proposed change will require the Loss of Power instruments to be OPERABLE when the associated diesel generator is OPERABLE. This revision to the Technical Specifications will l clarify the OPERABILITY requirements for Loss of Power instrumentation, and allow flexibility in scheduling the Channel Calibrations to support the intended fuel shuffle during RF05. The proposed change will not affect the safety function of any ESF in Operational j Page 2 of 4 m . ..- _ __. _ _. __

Conditions 4 and 5. This change is consistent with the improved Standard Technical Specifications (NUREG 1434).

Therefore, the proposed change will not be inimical to the common defense and security, or the health and safety of the public.

NO SIGNIFICANT HAZARDS CONSIDERATION ANALYSIS 10 CFR 50.91 requires that at the time a licensee requests an amendment, it must provide to the Commission its analysis using the standards in Section 50.92 about the issue of no significant hazards consideration. Therefore,in accordance with 10 CFR 50.91 and 10 ,

CFR 50.92, the following analysis has been performed.  ;

The operation of Nine Mile Point Unit 2, in sccs -der.cs with the oroaae-d amendment, wl!1 not involve a sianificant increase in the orobability or conseauence of an meddant previousiv evaluated.

The proposed change would require the Loss of Power instruments to be OPERABLE in Operational Conditions 4 and 5 only when the associated diesel generator is required to be OPERABLE. The Loss of Power relays provide a suppcrt function to initiate the associated i diesel generator start and bus unloading sequences. If that diesel generator is not in service, the loss of power relays perform no safety function. Therefore, relating diesel generator OPERABILITY and Loss of Power instrument OPERABILITY will not involve an increase in the probability of an accident previously evaluated.

i The proposed change does not affect the requirements for ESF OPERABILITY. The change  !

does not affect diesel generator response to a loss of voltage or degraded voltage on the  !

Divisional 4.16 kv electrical buses when the diesel generator is required to be OPERABLE.  !

Automatic response of the ESF functions is unaffected by removing the Loss of Power relays from service under these conditions, therefore, the proposed change will not involve a significant increase in the consequences of an accident previously evaluated.

The onoration of Nine Mile Point Unit 2, in accordance with the nronosed amendment, will  :

not create the nossibility of a new or different kind of accident from any accident  !

oreviousiv evaluated. l The proposed change does not involve a modification of plant equipment nor does it change the way the equipment will be maintained or operated. The revision to Technical Specifications will continue to require the Loss of Power instrumentation to be OPERABLE ,

when the associated diesel generator is required to be OPERABLE. The Loss of Power l instruments will continue to perform their safety function of initiating the diesel generator start and bus unloading sequences. ,

l Therefore, this proposed change will not create the possibility of a new or different kind of accident from any previously evaluated.

i The oneration of Nine Mile Point Unit 2,in accordance with the oronosed amendment, will  !

not involve a sianificant reduction in a marain of safety.

The proposed change will not affect the OPERABILITY, operation or reliability of any ESF l function including the diesel generators. All ESF functions will remain available during l postulated accidents with a loss of offsite electrical power. The change simply clarifies  !

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- t when the Loss of Power instruments are required to be OPERABLE during Operational Conditions 4 and 5. Therefore, the proposed change will not involve a significant j reduction in a margin of safety.

Niagara Mohawk's evaluation of this proposed amendment to Technical Specifications pursuant to 10 CFR 50.91 has determined that it involves no significant hazards  ;

consideration.

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