Text

Amends 124 & 109 to Licenses NPF-11 & NPF-18,respectively, Revise Bypass Logic for Main Steam Isolation Valve Isolation Actuation Instrumentation on Condenser Low Vacuum as Stated in TS Tables 3.3.2-1 & 4.3.2.1-1
	ML20216G957
Person / Time
Site:	LaSalle
Issue date:	04/14/1998
From:	Skay D; NRC (Affiliation Not Assigned)
To:	;
Shared Package
ML20216G964	List: ML20216G957; ML20216G977;
References
	NUDOCS 9804200536
	Download: ML20216G957 (15)
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UNITED STATES g

j NUCLEAR REGULATORY COMMISSION WAsHINoToN, D.C. 30e064001

\\...../

COMMONWEALTH EDISON COMPANY DOCKET NO. 50-373 LASALLE COUNTY STATION. UNIT 1 AMENDMENT TO FACILITY OPERATING LICENSE Amendment No.124 License No. NPF-11 1.

The Nuclear Regulatory Commission (the Commission) has found thet:

A.

The application for amendment filed by the Commonwealth Edison Company (the licensee), dated December 12,1997, complies with the standards and requirements of the Atomic Energy Act of 1954, as amended (the Act), and the Commission's regulations set forth in 10 CFR Chapter I; B.

The facility will operate in conformity with the application, the provisions of the Act, and the regulations of the Commission; C.

There is reasonable assurance: (i) that the activities authorized by this amendment can be conducted without endangering the health and safety of the public, and (ii) that such activities will be conducted in compliance with the Commission's regulations set forth in 10 CFR Chapter I; D.

The issuance of this amendment will not be inimical to the common defense and '

security or to the health and safety of the public; and E.

The issuance of this amendment is in accordance with 10 CFR Part 51 of the Commission's regulations and all applicable requirements have been satisfied.

2.

Accordingly, the license is amended by changes to the Technical Specifications as indicated in the enclosure to this license amendment and paragraph 2.C.(2) of the Facility Operating License No. NPF-11 is hereby amended to read as follows:

i 9804200536 980414 PDR ADOCK 05000373 P

PDR

- (2) Technical Specifications and Environmental Protection Plan The Technical Specifications contained in Appendix A, as revised through Amendment No.

124, and the Environmental Protection Plan contained in Appendix B, are hereby incorporated in the license. The licensee shall operate the facility in accordance with the Technical Specirmations and the Environmental Protection Plan.

3.

This license amendment is effective as of the date of its issuance and shall be implemented prior to startup from L1F35.

FOR THE NUCLEAR REGULATORY COMMISSION w& W

/

Donna M. Skay, Project Man er Project Directorate ill-2 Division of Reactor Projects - Ill/lV Office of Nuclear Reactor Regulation

Attachment:

Changes to the Technical Specifications Date of Issuance:

April 14, 1998 1

ATTACHMENT TO LICENSE AMENDMENT NO.124 FACILITY OPERATING LICENSE NO. NPF-11 DOCKET NO. 50-373 Replace the following pages of the Appendix "A" Technical Specifications with the enclosed pages. The revised pages are identified by amendment number and contain a verticalline indicating the area of change.

REMOVE INSERT 3/4 3-14 3/4 3-14 3/4 3-22 3/4 3-22 B 3/4 3-2 B 3/4 3-2 B 3/4 3-2a B 3/4 3-2a B 3/4 3-2b 4

TABLE 3.3.2-1 (Continued)

ISOLATION ACTUATION INSTRUMENTATION ACTION ACTION 20 Be in at least HOT SHUTDOWN within 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months and in COLD SHUTDOWN within the next 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months .

ACTION 21 -

Be in at least STARTUP with the associated isolation valves closed within 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months or be in at least HOT SHUTDOWN within 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months and in COLD SHUTDOWN within the next 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months .

ACTION 22 Close the affected system isolation valves within I hour and declara the affected system inoperable.

Be in at least STARTUP within 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months .

ACTION 23 Establish SECONDARY CONTAINMENT INTEGRITY with the standby gas ACTION 24 treatment system operating within I hour.

Lock the affected system isolation valves closed within I hour ACTION 25 and declare the affected system inoperable.

ACTION 26 -

Provided that the manual initiation function is OPERABLE for each other group valve, inboard or outboard, as applicable, in each line, restore the manual initiation function to OPERABLE status within 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months ; otherwise, restore the manual initiation function to OPERABLE status within 8 hours9.259259e-5 days 0.00222 hours 1.322751e-5 weeks 3.044e-6 months ; otherwise:

a.

Be in at least HOT SHUTDOWN within the next 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months and in COLD SHUTDOWN within the following 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months , or b.

Close the affected system isolation valves within the next hour and declare the affected system inoperable.

NOTES May be bypassed with all turbine stop valves not full open.

l When handling irradiated fuel in the secondary containment and during CORE ALTERATIONS and operations with a potential for draining the reactor vessel.

During CORE ALTERATIONS and operations with a potential for draining the reactor vessel.

(a) Deleted.

(b) A channel may be placed in an inoperable status for up to 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months for required surveillance without placing the channel in the tripped condition provided at least one other OPERABLE channel in the same trip system is monitoring that parameter.

In addition for those trip systems with a design providing only one channel per trip system, the channel may be placed in an inoperable status for up to 8 hours9.259259e-5 days 0.00222 hours 1.322751e-5 weeks 3.044e-6 months for required surveillance testing without placing the channel in the tripped condition provided that the redundant isolation valve, inboard or outboard, as applicable, in each line is operable and all required actuation instrumentation for that redundant valve is OPERABLE, or place the trip system in the tripped condition.

(c) Also actuates the standby gas treatment system.

(d) A channel is OPERABLE if 2 of 4 instements in that channel are OPERABLE.

(e) Also actuates secondary containment ventilation isolation dampers per Table 3.6.5.2-1.

(f) Closes only RWCU system inlet outboard valve.

LA SALLE - UNIT 1 3/4 3-14 Amendment No.124

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INSTRUMENTATION BASES 3/4.3.1 REACTOR PROTECTION SYSTEM INSTRUMENTATION (Continued)

Functional Units, response time testing for the remaining channel components, including any analog trip units, is required. This allowance is supported by NED0-32291-A, " System Analyses for the Elimination of Selected Response Time Testing Requirements," October 1995.

Response time may be demonstrated by any series of sequential, overlapping or total channel test measurement, provided such tests demonstrate the total channel response time as defined. Sensor response time verification may be demonstrated by either (1) inplace, onsite or offsite test measurements, or (2) utilizing replacement sensors with certified response times.

3/4.3.2 ISOLATION ACTUATION INSTRUMENTATION This specification ensures the effectiveness of the instrumentation used to mitigate the consequences of accidents by prescribing the OPERABILITY trip setpoints and response times for isolation of the reactor systems. When necessary, one channel may be inoperable for brief intervals to conduct required surveillance.

Both channels of each trip system for the main steam tunnel ventilation system differential temperature may be placed in an inoperable status for up to 4 hours4.62963e-5 days 0.00111 hours 6.613757e-6 weeks 1.522e-6 months for required reactor building ventilation system maintenance and testing and 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months due to loss of reactor building ventilation or for the required secondary containment Leak Rate test without placing the trip system in the tripped condition.

This will allow for maintaining the reliability of the ventilation system and secondary containment.

Specified surveillance intervals and surveillance and maintenance outage times have~been determined in accordance with NEDC-30851P-A, Supplement 2, " Technical Specification Improvement Analyses for BWR Isolation Instrumentation Common to RPS and ECCS Instrumentation, March 1989, and with NEDC-31677P-A, " Technical Specification Improvement Analysis for BWR Isolation Actuation Instrumentation", July 1990. When a channel is placed in an inoperable status solely for performance of required surveillances, entry into LC0 and required ACTIONS may be delayed, provided the associated function maintains primary containment isolation capability.

Some of the trip settings may have tolerances explicitly stated where both the high and low values are critical and may have a substantial effect on safety. The setpoints of other instrumentation, where only the high or low end of the setting have a direct bearing on safety, are established at a level away from the normal operating range to prevent inadvertent actuation of the systems involved.

The Condenser Vacuum - Low Function isolates group 1 valves and is provided to prevent overpressurization of the main condenser in the event of a loss of the main condenser vacuum.

Since the integrity of the condenser is an assumption in offsite dose calculations, the Condenser Vacuum - Low Function is assumed to be OPERABLE and capable of initiating closure of the MSIVs. The LA SALLE - UNIT 1 B 3/4 3-2 Amendment No. 124 I

i

INSTRUMENTATION BASES 3/4.3.2 ISOLATION ACTUATION INSTRUMENTATION (Continued) closure of the MSIVs is initiated to prevent the addition.of steam that would lead to additional condenser pressurization and possible rupture _ of the diaphragm installed to protect the turbine exhaust hood, thereby preventing a potential radiation leakage path following an accident.

' As noted (footnote

to Tables 3.3.2-1 and 4.3.2.1-1), the channels are not required to be OPERABLE in MODES 2 and 3, when all turbine stop valves (TSVs) are not full open, since the potential for condenser overpressurization is minimized. Switches are provided to manually bypass the channels when all TSVs are not full open. TSV position setpoints are controlled by TS 2.2.1 and surveillances are performed per TS 4.3.1.

The TSV closure scram bypass below 30% power (TS Table 3.3.1-1, Note i) does not affect the TSV position interlocks for the condenser vacuum - low bypass logic.

Except for the MSIVs, the safety analysis does not address individual sensor response times or the response times of the logic systems to which the sensors are connected. For A.C. operated valves, it is assumed that the A.C.

power supply is lost and is restored by startup of the emergency diesel generators.

In this event, a time of 13 seconds is assumed before the valve starts to move. The safety analysis considers an allowable inventory-loss which in turn determines the valve speed in conjunction with the 13 second delay.

For the sensors associated with MSIV isolation, instrumentation channels are not required to be response time tested. Response time testing for the remaining channel components, including any analog trip units, is required.

This allowance is supported by NED0-32291-A, " System Analyses for the Eilmination of Selected Response Time Testing Requirements," October 1995.

3/4.3.3 EMERGENCY CORE COOLING SYSTEM ACTUATION INSTRUMENTATION The emergency core cooling system actuation instrumentation is provided to initiate actions to mitigate the consequences of accidents that are beyond the ability of the operator to control. This specification provides the OPERABILITY requirements, trip setpcints and response times that will ensure effectiveness of the systems to provide the design protection. Although the instruments are listed by system, in some cases the same instrument may be used to send the actuation signal to more than one system at the same time.

Per Note #, the ECCS actuation instrument channels are not required to be response time tested..The overall ECCS response time requirement, which includes diesel generator injection valves, pumps, and other components, still applies. This allowance is supported by NED0-32291-A, " System Analyses for the Elimination of Selected Response Time Testing Requirements," October 1995.

LA SALLE - UNIT 1 B 3/4 3-2a Amendment No.124

)

1

INSTRUMENTATION 1

l 88112.

3/4.3.3 EMERGENCY CORE COOLING SYSTEM ACTUATION INSTRUMENTATION (Continued)

Specified surveillance intervals and surveillance and maintenance outage times have been determined in accordance with NEDC-30936P-A, " Technical Specification Improvement Methodology (With Demonstration for BWR ECCS Actuation Instrumentation)", Parts 1 and 2, December 1988, and RE-025 Revision 1, " Technical Specifiention Improvement Analysis for the Emergency Core Cooling System Actuation Instrumentation for LaSalle County Station, 1

Units 1 and 2", April 1991. When a channel is placed in an inoperable status solely for performance of required surveillances, entry into LC0 and required ACTIONS may be delayed, provided the associated function maintains ECCS initiation capability.

1 1

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LA SALLE - UNIT 1 B 3/4 3-2 b Amendment No.124

[

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UNITED STATES j

NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 30666-0001 9.....,[

4 I

COMMONWEALTH EDISON COMPANY QOCKET NO. 50-374 LASALLE COUNTY STATION. UNIT 2 AMENDMENT TO FACILITY OPERATING LICENSE l

Amendment No.109 License No. NPF-18 1.

The Nuclear Regulatory Commission (the Commission) has found that:

1 A.

The application for amendment filed by the Commonwealth Edison Company (the licensee), dated December 12,1997, complies w;th the standards end requirements of the Atomic Energy Act of 1954, as amended (the Act), and the Commission's regulations set forth in 10 CFR Chapter I; B.

The facility will operate in conformity with the application, the provisions of the Act, and the regulations of the Commission; l

l C.

There is reasonable assurance: (i) that the activities authorized by this

)

amendment can be conducted without endangering the health and safety of the l

public, and (ii) that such activities will be conducted in compliance with the Commission's regulations set forth in 10 CFR Chapter I; l

D.

The issuance of this amendment will not be inimical to the common defense and security or to the health and safety of the public; and E.

The issuance of this amendment is in accordance with 10 CFR Part 51 of the Commission's regulations and all applicable requirements have been satisfied.

l l

2.

Accordingly, the license is amended by changes to the Technical Specifications as indicated in the enclosure to this license amendment and paragraph 2.C.(2) of the Facility Operating License No. NPF-18 is hereby amended to read as follows:

l l

l i

l

r

. (2)

Technical Specifications and Environmental Protection Plan The Technical Specifications contained in Appendix A, as revised through l

Amendment No. 109, and the Environmental Protection Plan contained in Appendix B, are hereby incorporated in the license. The licensee shall operate the facility in accordance with the Technical Specifications and the Environmental Protection Plan.

3.

This license amendment is effective as of the date of its issuance and shall be implemented prior to startup from L2R07.

FOR THE NUCLEAR REGULATORY COMMISSION g q/b' Donna M. Skay, Project M pr Project Directorate Ill-2 Division of Reactor Projects - til/IV Office of Nuclear Reactor Regulation l

l

Attachment:

Changes to the Technical Specifications Date of issuance: April 14, 1998 l

t i

1

ATTACHMENT TO LICENSE AMENDMENT NO,109 l

i FACILITY OPERATING LICENSE NO. NPF-18 DOCKET NO. 50-374 Replace the following pages of the Appendix "A" Technical Specifications with the enclosed i

I pages. The revised pages are identified by amendment number and contain a vertical line indicating the area of change.

REMOVE INSERT 3/4 3-14 3/4 3-14 3/4 3-22 3/4 3-22 B 3/4 3-2 B 3/4 3-2 B 3/4 3-2a B 3/4 3-2a I

l

i I

TABLE 3.3.2-1 (Continued)

ISOLATION ACTUATION INSTRUMENTATION ACTION STATEMENTS ACTION 20 Be in at least HOT SHUTDOWN within 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months and in COLD SHUTDOWN within the next 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months .

ACTION 21 -

Be in at least STARTUP with the associated isolation valves closed within 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months or be in at least HOT SHUTDOWN within 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months and in COLD SHUTDOWN within the next 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months .

ACTION 22 Close the affected system isolation valves within I hour and declare the affected system inoperable.

ACTION 23 Be in at least STARTUP within 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months .

ACTION 24 Establish SECONDARY CONTAINMENT INTEGRITY with the standby gas treatment system operating within I hour.

ACTION 25 -

Lock the affected system isolation valves closed within I hour and declare the affected system inoperable.

ACTION 26 -

Provided that the manual initiation function is OPERABLE for each other group valve, inboard or outboard, as applicable, in each I

line, restore the manual initiation function to OPERABLE status within 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months ; otherwise, restore the manual initiation function to OPERABLE status within 8 hours9.259259e-5 days 0.00222 hours 1.322751e-5 weeks 3.044e-6 months ; otherwise:

I a.

Be in at least HOT SHUTDOWN within the next 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months and in COLD SHUTDOWN within the following 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months , or b.

Close the affected system isolation valves within the next hour and declare the affected system inoperable.

TABLE NOTATIONS May be bypassed with all turbine stop valves not full open.

When handling irradiated fuel in the secondary containment and during CORE 1

ALTERATIONS and operations with a potential for draining the reactor vessel.

{

During CORE ALTERATIONS and operations with a potential for draining the reactor vessel.

(a) Deleted.

(b) A channel may be placed in an inoperable status for up to 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months for required surveillance without placing the channel in the tripped condition provided at least one other OPERABLE channel in the same trip system is monitoring that parameter.

In addition for those trip systems with a design providing only one channel per trip system, the channel may be placed in an inoperable status for up to 8 hours9.259259e-5 days 0.00222 hours 1.322751e-5 weeks 3.044e-6 months for required surveillance testing without placing the channel in the tripped condition provided that the redundant isolation valve, inboard or outboard, as applicable, in each line is operable and all required actuation instrumentation for that redundant valve is OPERABLE, or place the trip system in the tripped condition.

(c) Also actuates the standby gas treatment system.

(d) A channel is OPERABLE if 2 of 4 instruments in that channel are OPEPABLE.

(e) Also actuates secondary containment ventilation isolation dampers per Table 3.6.5.2-1.

(f) Closes only RWCU system inlet outboard valve.

l LA SALLE - UNIT 2 3/4 3-14 Amendment No. 109 i

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INSTRUMENTATION BASES 3/4.3.1 REACTOR PROTECTION SYSTEM INSTRUMENTATION (Continued)

Functional Units, responsa time testing for the remaining channel components, including any analog trip units, is required. This allowance is supported by NED0-32291-A, " System Analyses for the Elimination of Selected Response Time Testing Requirements," October 1995.

Response time may be demonstrated by any series of sequential, overlapping or total channel test measurement, provided such tests demonstrate the total channel response time as defined. Sensor response time verification may be demonstrated by either (1) inplace, onsite or offsite test measurements, or (2) utilizing replacement sensors with certified response times.

1/4.3.2 ISOLATION ACTUATION INSTRUMENTATION This specification ensures the effectiveness of the instrumentation used to mitigate the consequences of accidents by prescribing the OPERABILITY trip setpoints and response times for isolation of the reactor systems. When necessary, one channel may be inoperable for brief intervals to conduct required surveillance. Both channels of each trip system for the main steam tunnel ventilation system differential temperature may be placed in an inoperable status for up to 4 hours4.62963e-5 days 0.00111 hours 6.613757e-6 weeks 1.522e-6 months for required reactor building ventilation system maintenance and testing and 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months due to loss of reactor building ventilation or for the required secondary containment Leak Rate test without placing the trip system in the tripped condition. This will allow for maintaining the reliability of the ventilation system and secondary containment.

Specified surveillance intervals and surveillance and maintenance outage times have been determined in accordance with NEDC-30851P-A, Supplement 2, " Technical Specification Improvement Analyses for BWR Isolation Instrumentation Common to RPS and ECCS Instrumentation", March 1989, and with NEDC-31677P-A, " Technical Specification Improvement Analysis for BWR Isolation Actuation Instrumentation", July 1990. When a channel is placed in an inoperable status solely for performance of required surveillances, entry into LCO and required ACTIONS may be delayed, provided the associated function maintains primary containment isolation capability.

Some of the trip settings may have tolerances explicitly stated where both the high and low values are i

critical and may have a substantial effect on safety. The setpoints of other instrumentation, where only the high or low end of the setting have a direct bearing on safety, are established at a level away from the normal operating range to prevent inadvertent actuation of the systems involved.

The Condensor Vacuum - Low Function isolates group 1 valves and is provided to prevent overpressurization of the main condenser in the event of a loss of the main condenser vacuum.

Since the integrity of the condenser is an l

assumption in offsite dose calculations, the Condenser Vacuum - Low Function is assumed to be OPERABLE and capable of initiating closure of the MSIVs. The closure of the MSIVs is initiated to prevent the addition of steam that would LA SALLE - UNIT 2 B 3/4 3-2 Amendment No.109

INSTRUMENTATION BASES 3/4.3.2 ISOLATION ACTUATION INSTRUMENTATION (Continued) lead to additional condenser pressurization and possible rupture of the i

diaphragm installed to protect the turbine exhaust hood, thereby preventing a potential radiation leakage path following an accident.

l As noted (footnote

to Tables 3.3.2-1 and 4.3.2.1-1), the channels are not required to be OPERABLE in MODES 2 and 3, when all turbine stop valves

.(TSVs) are not full open, since the potential for condenser overpressurization l

1s minimized.

Switches are provided to manually bypass the channels when all l

TSVs are not full open. TSV position setpoints are controlled by TS 2.2.1 and surveillances are performed per TS 4.3.1.

The TSV closure scram bypass below l

30% power (TS Table 3.3.1-1, Note 1) does not affect the TSV position l

interlocks for the condenser vacuum - low bypass logic.

Except for the MSIVs, the safety analysis does not address individual sensor response times or the response times of the logic systems to which the sensors are connected.'

For A.C. operated valves, it is assumed that the A.C.

power supply is lost and is restored by startup of the emergency diesel generators.

In this event, a time of 13 seconds is assumed before the valve l

starts to move. The safety analysis considers an allowable inventory loss l

which in turn determines the valve speed in conjunction with the 13 second I

delay.

For the sensors associated with MSIV isolation, instrumentation channels

_are not required to be response time tested.

Response time testing for the L

l remaining channel components, including any analog trip units, is required.

This allowance is supported by NED0-32291-A, " System Analyses for the L

Elimination of Selected Response Time Testing Requirements," October 1995.

3/4.3.3 EMERGENCY CORE COOLING SYSTEM ACTUATION INSTRUMENTATION The emergency core cooling system actuation instrumentation is provided to initiate actions to mitigate the consequences of accidents that are beyond the ability of the operator to control. This specification provides the l

OPERABILITY requirements, trip setpoints and response times that will ensure effectiveness of the systems to provide the design protection..Although the instruments are listed by system, in some cases the same instrument may be used to send.the actuation signal to more than one system at the same time.

Per note #, the ECCS actuation instrument channels are not required to be response time tested. The overall ECCS res includes diesel generator injection valves,ponse time requirement, which pumps, and other ccmponents, still applies. This allowance is supported by NED0-32291-A, " System Analyses for l

the Elimination of Selected Response Time Testing Require wits," October 1995.

LA SALLE - UNIT 2 B 3/4 3-2a Amendment No.

109

)

ML20216G957

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