Text

Proposed Tech Specs 3/4.5.E & 3/4.5.F,revising Reactor Pressure Requirement at Which HPCI & RCIC Sys Must Be Operable
	ML18033A880
Person / Time
Site:	Browns Ferry
Issue date:	08/09/1989
From:	; TENNESSEE VALLEY AUTHORITY
To:	;
Shared Package
ML18033A879	List: ML18033A878; ML18033A880;
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	NUDOCS 8908170377
	Download: ML18033A880 (27)
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ENCLOSURE 1 PROPOSED TECHNICAL SPECIFICATIONS REVISIONS BRONNS FERRY NUCLEAR PLANT UNITS 1, 2, AND 3 8908i70377 890809 PDR ADOCK 05000259 PNU

3.5/4.5 CORE AND CONTAINMENT COOLING SYSTEMS LIMITING CONDITIONS FOR OPERATION SURVEILLANCE REQUIREMENTS 3.5.D E ui ment Area Coolers 4.5.D E ui ment Area Coolers

1. The equipment area cooler 1. Each equipment area cooler

-associated with each RHR is operated in conjunction pump and the equipment with the equipment served area cooler associated by that particular cooler; with each set of core therefore, the equipment spray pumps (A and C area coolers are tested at or 8 and D) must be the same frequency as the OPERABLE at all times pumps which they serve.

when the pump or pumps served by that specific cooler is considered to 'e OPERABLE.

2. Hhen an equipment area cooler is not OPERABLE, the pump(s) served by that cooler must be considered inoperable for Technical Specification purposes."

E. Hi h Pressure Coolant In ection. E. Hi h Pressure Coolant S stem (HPCIS) In'ection S stem (HPCIS)

The HPCI system shall be 1. HPCI Subsystem testing OPERABLE whenever there is shall be performed as irradiated fuel in the follows:

reactor vessel and the reactor vessel pressure a. Simulated Once/18 is greater than 150 psig, Automatic months except as specified in Actuation Specification 3.5.E.2. Test OPERABILITY shall be determined within 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months b. Pump PER after reactor steam pressure OPERA- Specification reaches 150 psig from a COLD BILITY 1.0.MM CONDITION, or alternatively

c. Oper-PRIOR TO STARTUP by using an auxiliary steam supply.

" Motor ated Valve PER Specification OPERABILITY 1.0,MM de Flow Rate at Once/3 normal months reactor vessel operating pressure BFN 3.5/4.5-13 Unit 1

~ ~

3.5/4.5 CORE AND CONTAINMENT COOLING SYSTEMS LIMITING CONDITIONS FOR OPERATION SURVEILLANCE REQUIREMENTS 3.5.E Hi h Pressure Coolant In ection 4.5.E Hi h Pressure Coolant In ection 4.5.E.1 (Cont'd)

e. Flow Rate at Once/18 150 psig months The HPCI pump shall deliver at least 5000 gpm during each flow rate test.

2. If the HPCI system is 2. Hhen it is determined that inoperable, the reactor may the HPCIS is inoperable the remain in operation for a ADS actuation logic, the period not to exceed 7 days, RCICS,-'-'the RHRS (LPCI), and provided the ADS, CSS, RHRS the CSS shall be (LPCI), and RCICS are demonstrated to be OPERABLE OPERABLE. immediately. The RCICS and ADS logic shall be demonstrated to be OPERABLE daily thereafter.

3. If Specifications 3.5.E.1 or 3.5.E.2 are not met, an orderly shutdown shall

~

be initiated and the reactor vessel pressure shall be reduced to 150 psig or less within 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months .

F. Reactor Core Isolation Coolin F. Reactor Core Isolation Coolin

~ C~

((~ S stem (RCICS)

The RCICS shall be OPERABLE 1. RCIC Subsystem testing shall whenever there is irradiated be performed as follows:

fuel in the reactor vessel and the reactor vessel a. Simulated Once/18 month pressure is above 150 psig, Automatic except as specified in Actuation Test 3.5.F.2. OPERABILITY "shall be determined within 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months b. Pump Per after reactor steam pressure OPERABILITY Specification reaches 150 psig from a COLD 1.0.MM CONDITION or alternatively prior to STARTUP by using an c. Motor-Operated Per auxiliary steam supply. Valve Specifi-OPERABILITY cation 1.0.MM BFN 3,5/4.5-14 Unit 1

3.5/4.5 CORE AND CONTAINMENT COOLING SYSTEMS LIMITING CONDITIONS FOR OPERATION SURVEILLANCE REQUIREMENTS 3.5.F Reactor Core Isolation Coolin 4.5.F Reactor Core Isolation Coolin 4.5.F.l (Cont'd)

d. Flow Rate at Once/3 normal reactor months vessel operating pressure

e. Flow Rate at Once/18 150 psig months The RCIC pump shall deliver at least 600 gpm during each flow test.

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2 ~ If the RCICS is inoperable, 2. Hhen it is determined that the reactor may remain in the RCICS is inoperable, the operation for a period not HPCIS shall be demonstrated to exceed 7 days if the to be OPERABLE immediately.

HPCIS is OPERABLE during such time.

3. If Specifications 3.5.F.l or 3.5.F.2 are not met, an orderly shutdown shall be initiated and the reactor shall be depressurized to less than 150 psig within 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months .

G. Automatic De ressurization G. Automatic De ressurization

~t' 5 S stem (ADS)

1. Four of the six valves of 1. During each operating the Automatic cycle the following Depressurization System tests shall be performed

" on shall be OPERABLE: the ADS:

(1) PRIOR TO STARTUP a. A simulated automatic from a COLD CONDITION, actuation test shall or, be performed prior to STARTUP after each BFN 3.5/4.5-15 Unit 1

BASES 3.5.E The HPCIS is provided to assure that the reactor core is adequately cooled to limit fuel clad temperature in the event of a small break in the nuclear system and loss of coolant which does not result in rapid depressurization of the reactor vessel. The HPCI system permits the reactor to be shut down while maintaining sufficie'nt reactor vessel water level inventory until the vessel is depressuri'zed. -The HPCIS continues to operate until reactor vessel pressure is below the pressure It which LPCI operation or Core Spray system operation maintains core cooling. The capacity of the system is selected to provide the required core cooling. The HPCI pump is designed to pump 5000 gpm at reactor pressures between 1120 and 150 psig. The HPCIS is not required to be operable below 150 psig since this is well within the range of the low pressure cooling systems and below the pressure of any events for which HPCI is required to provide core cooling.

The HPCIS is not designed to operate at full capacity until reactor pressure exceeds 150 psig and the steam supply to the HPCI turbine is automatically isolated before reactor pressure decreases below 100 psig ~ The ADS, CSS, and RHRS (LPCI) must be OPERABLE when starting up from a Cold Condition. Steam pressure is sufficient at 150 psig to run the HPCI turbine for operability testing yet, still below the shutoff head of the CSS and RHRS pumps so they will inject water into the vessel if required. The ADS provides additional backup to reduce pressure to the range where the CSS and RHRS will inject into the vessel if necessary. Considering the low reactor pressure, the redundancy and availability of CSS, RHRS, and ADS during startup from a Cold Condition, twelve hours is allowed as a reasonable time to demonstrate HPCI operability once sufficient steam pressure becomes available. The alternative to demonstrate HPCI operability prior to startup using auxiliary steam is provided for plant operating flexibility.

Hith the HPCIS inoperable, a seven day period to return the system to service is justified based on the availability of the ADS, CSS, RHRS (LPCI) and the RCICS .

The availability of these redundant and diversified systems provides adequate assurance of core cooling while HPCIS is out of service.

The surveillance requirements, which are based on industry codes and standards, provide adequate assurance that the HPCIS will be OPERABLE when required.

BFN 3.5/4.5-30 Unit 1

3.5 BASES (Cont'd) 3.5.F Reactor Core Isolation Coolin S stem (RCICS)

The RCICS functions to provide core cooling and makeup water to the reactor vessel during shutdown and isolation from the main heat sink and for certain pipe break accidents. The RCICS provides its design flow between 150 psig and 1120 psig reactor pressure. Below 150 psig, RCICS is not 'required to be operable since this pressure is substantially below that for any events in which RCICS is required to provide core cooling. RCICS will continue to operate below 150 psig at reduced flow until it automatically isolates at greater than or equal to 50 psig reactor steam pressure. 150 psig is also below the shutoff head of the CSS and RHRS, thus, considerable overlap exists with the cooling systems that provide core cooling at low reactor pressure.

The ADS, CSS, and RHRS (LPCI) must be OPERABLE 'when starting up from a Cold Condition. Steam pressure is sufficient at 150 psig to run the RCIC turbine for operability testing, yet still below the shutoff head

'of the CSS and RHRS pumps so they will inject water into the vessel if-required. Considering the low reactor pressure and the availability of the low pressure coolant systems during startup from ~a Cold Condition, twelve hours is allowed as a reasonable time to demonstrate RCIC operability once sufficient steam pressure becomes available. The alternative to demonstrate RCIC operability prior to startup using auxiliary steam is provided for plant operating flexibility.

With the RCICS inoperable, a seven day period to return the system to service is justified based on the availability of the HPCIS to cool the core and upon consideration that the average risk associated with failure of the RCICS to cool the core when required is not increased.

The surveillance requirements, which are based on industry codes and standards, provide adequate assurance that the RCICS will be OPERABLE when required.

3.5.G Automatic De ressurization S stem (ADS)

This specification ensures the operability of the ADS under all conditions for which the depressurization of the nuclear system is an essential response to station abnormalities, The nuclear system pressure relief system provides automatic nuclear system depressurization for small breaks in the nuclear system so that the low-pressure coolant injection (LPCI) and the core spray subsystems can operate to protect the fuel barrier. hfote that this specification applies only to the automatic feature of the pressure relief system.

Specification 3.6.D specifies the requirements for the pressure relief function of the valves. It is possible for any number of the valves assigned to the ADS to be incapable of performing their ADS functions because of instrumentation failures, yet be fully capable of performing their pressure relief function.

BFN 3.5/4.5-31 Unit 1

3.5/4.5 CORE AND CONTAINMENT COOLING SYSTEMS LIMITING CONDITIONS FOR OPERATION SURVEILLANCE REQUIREMENTS 3.5.D E ui ment Area Coolers 4.-5.D E ui ment Area Coolers The equipment area cooler l. Each equipment area cooler

--associated with each RHR is operated in conjunction pump and the equipment with the equipment served area cooler associated by that particular cooler; with each set of core therefore, the equipment spray pumps (A and C area coolers are tested at or B and D) must be the same frequency as the OPERABLE at all times pumps which they serve.

when the pump or pumps served by that specific cooler is considered to 'e OPERABLE.

2. Hhen an equipment area cooler is not OPERABLE, the pump(s) served by that cooler must be considered inoperable for Technical Specification purposes.

E. Hi h Pressure Coolant In'ection E. Hi h Pressure Coolant S stem (HPCIS) In ection S stem (HPCIS)

The HPCI system shall be 1. HPCI Subsystem testing OPERABLE whenever there is shall be performed as irradiated fuel in the follows:

reactor vessel and the reactor vessel pressure a. Simulated Once/18 is greater than 150 psig, Automatic months except as specified in Actuation Specification 3.5.E.2. Test OPERABILITY shall be determined within 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months b. Pump PER after reactor steam pressure OPERA- Specification reaches 150 psig from a COLD BILITY 1.0.MM CONDITION, or alternatively

c. Oper-PRIOR TO STARTUP by using an auxiliary steam supply.

" Motor ated Valve PER Specification OPERABILITY 1.0.MM

d. Flow Rate at Once/3 normal months reactor vessel operating pressure BFN 3.5/4.5 Unit 2

3.5/4.5 CORE AND CONTAINMENT COOLING SYSTEMS LIMITING CONDITIONS FOR OPERATION SURVEILLANCE REQUIREMENTS 3.5.E Hi h Pressure Coolant In ection 4.5.E Hi h Pressure Coolant In ection 4.5.E.1 (Cont'd) e, Flow Rate at Once/18 150 psig months The HPCI pump shall deliver at least 5000 gpm during each flow rate test.

2. If the HPCI system is 2. Nhen it is determined that inoperable, the reactor may the HPCIS is inoperable the remain in operation for a ADS actuation logic, the period not to exceed 7 days, RCICS, the RHRS (LPCI), and provided the ADS, CSS, RHRS the CSS shall be (LPCI), and RCICS are demonstrated to be OPERABLE OPERABLE. immed.iately. The RCICS and ADS logic shall be demonstrated to be OPERABLE daily thereafter.

3. If Specifications 3.5.E.l or 3.5.E.2 are not met, an orderly shutdown shall be initiated and the reactor vessel pressure shall be reduced to 150 psig or less within 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months .

F. Reactor Core Isolation Coolin F. Reactor Core Isolation Coolin C S stem (RCICS)

The RCICS shall be OPERABLE 1 ~ RCIC Subsystem testing shall whenever there is irradiated be performed as follows:

fuel in the reactor vessel and the reactor vessel a. Simulated Once/18 month pressure is above 150 psig, Automatic except as specified in Actuation Test 3.5.F.2. OPERABILITY shall be determined within 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months b. Pump Per after reactor steam pressure OPERABILITY Specification reaches 150 psig from a COLD 1.0.MM CONDITION or alternatively prior to STARTUP by using an c. Motor-Operated Per auxiliary steam supply. Valve Specifi-OPERABILITY cation 1.0.MM BFN 3.5/4.5-14 Unit 2

3.5/4.5 CORE AND CONTAINMENT COOLING SYSTEMS LIMITING CONDITIONS FOR OPERATION SURVEILLANCE REQUIREMENTS 3.5.F Reactor Core Isolation Coolin 4.5.F Reactor Core Isolation Coolin 4.5.F.l (Cont'd)

d. Flow Rate at Once/3 normal reactor months vessel operating pressure

e. Flow Rate at Once/18 150 psig months

~

The RCIC pump shall deliver at least 600 gpm during each flow test.

2. If the RCICS is inoperable, 2. Hhen it is determined that the reactor may remain in the RCICS is inoperable, the operation for a period not HPCIS shall be demonstrated to exceed 7 days if the to be OPERABLE immediately.

HPCIS is OPERABLE during such time.

3. If Specifications 3.5.F.1 or 3.5.F.2 are not met, an orderly shutdown shall be initiated and the reactor shall be depressurized to less than 150 psig within 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months .

G. Automatic De ressurization G. Automatic De ressurization S stem (ADS)

1. Four of the six valves of 1. During each operating the Automatic cycle the following Depressurization System tests shall be performed

" on shall be OPERABLE: the ADS:

(1) PRIOR TO STARTUP a. A simulated automatic from a COLD CONDITION, actuation test shall or, be performed prior to STARTUP after each BFN 3.5/4.5-15 Unit 2

BASES 3.5.E The HPCIS is provided to assure that the reactor core is adequately cooled to limit fuel clad temperature in the event of a small break in the nuclear system and loss of coolant which does not result in rapid depressurization of the reactor vessel. The HPCI system permits the reactor to be shut down while maintaining sufficient reactor vessel water level inventory until the vessel is depressurized'. -The HPCIS continues to operate until reactor vessel pressure is below the pressure at which LPCI operation or Core Spray system operation maintains core cooling. The capacity of the system is selected to provide the required core cooling. The HPCI pump is designed to pump 5000 gpm at reactor pressures between 1120 and 150 psig. The HPCIS is not required to be operable below 150 psig since this is well within the range of the low pressure cooling systems and below the pressure of any events for which HPCI is required to provide core cooling.

The HPCIS is not designed to operate at full capacity until reactor pressure exceeds 150 psig and the steam supply to the HPCI turbine is automatically isolated before reactor pressure decreases below 100 psig. The ADS, CSS, and RHRS (LPCI) must be OPERABLE when starting up from a Cold Condition. Steam pressure is sufficient at 150 psig to run the HPCI turbine for operability testing yet still below the shutoff head of the CSS and RHR~3 pumps so they will inject water into the vessel if required. The ADS provides additional backup to reduce pressure to the range where the CSS and RHRS will inject into the vessel if necessary. Considering the low reactor pressure, the redundancy and availability of CSS, RHRS, and ADS during startup from a Cold Condition, twelve hours is allowed as a reasonable time to demonstrate HPCI operability once sufficient steam pressure becomes available. The alternative to demonstrate HPCI operability prior to startup using auxiliary steam is provided for plant operating flexibility.

Hith the HPCIS inoperable, a seven day period to return the system to service is justified based on the availability of the ADS, CSS, RHRS (LPCI) and the RCICS.

The availability of these redundant and diversified systems provides adequate assurance of core cooling while HPCIS is out of service.

The surveillance requirements, which are based on industry codes and standards, provide adequate assurance that the HPCIS will be OPERABLE when required.

BFN 3.5/4.5-28 Unit 2

3.5 BASES (Cont'd) 3.5.F Reactor Core Isolation Coolin S stem (RCICS)

The RCICS functions to provide core cooling and makeup water to the reactor vessel during shutdown and isolation from the main heat sink and for certa'in pipe break accidents. The RCICS provides its design flow be'tween 150 psig and 1120 psig reactor pressure. Below 150 psig, RCICS is not 'required to be operable since this pressure is substantially below that for any events in which RCICS is required to provide core cooling. RCICS will continue to operate below 150 psig at reduced flow until it automatically isolates at greater than or equal to 50 psig reactor steam pressure. 150 psig is also below the shutoff head of the CSS and RHRS, thus, considerable overlap exists with the cooling systems that provide core cooling at low reactor pressure.

The ADS, CSS, and RHRS (LPCI) must be OPERABLE when starting up from a Cold Condition. Steam pressure is sufficient at 150 psig to run the

'f RCIC turbine for operability testing, yet still below the shutoff head the CSS and RHRS pumps so they will inject water into the vessel required. Considering the low reactor pressure and f>he availability of if the low pressure coolant systems during startup from'>a Cold Condition, twelve hours is allowed as a reasonable time to demonstrate RCIC operability once sufficient steam pressure becomes available. The alternative to demonstrate RCIC operability prior to startup using auxiliary steam is provided for plant operating flexibility.

Hith the RCICS inoperable, a seven day period to return the system to service is justified based on the availability of the HPCIS to cool the core and upon consideration that the average risk associated with failure of the RCICS to cool the core when required is not increased'he surveillance requirements, which are based on industry codes and standards, provide adequate assurance that the RCICS will be OPERABLE when required.

3.5.G Automatic De ressurization S stem (ADS)

This specification ensures the operability of the ADS under all conditions for which the depressurization of the nuclear system is an essential response to station abnormalities.

The nuclear system pressure relief system provides automatic nuclear system depressurization for small breaks in the n'uclear system so that the low-pressure coolant injection (LPCI) and the core spray subsystems can operate to protect the fuel barrier. Note that this specification applies only to the automatic feature of the pressure relief system.

Specification 3.6.D specifies the requirements for the pressure relief function of the valves. It is possible for any number of the valves assigned to the ADS to be incapable of performing their ADS functions because of instrumentation failures, yet be fully capable of performing their pressure relief function.

BFN 3.5/4.5-29 Unit 2

3.5/4.5 CORE AND CONTAINMENT COOLING SYSTEMS LIMITING CONDITIONS FOR OPERATION SURVEILLANCE REQUIREMENTS 3.5.D E ui ment Area Coolers 4.5.D E ui ment Area Coolers The eqUipment area cooler l. Each equipment area cooler

-associated with each RHR is operated in conjunction pump and the equipment with the equipment served area cooler associated by that particular cooler; with each set of core therefore, the equipment spray pumps (A and C area coolers are tested at or B and D) must be the same frequency as the OPERABLE at all times pumps which they serve.

when the pump or pumps served by that specific cooler is considered to be OPERABLE.

2. When an equipment area cooler is not OPERABLE, the pump(s) served by that cooler must be considered inoperable for Technical Specification purposes.

E. Hi h Pressure Coolant In ection E. Hi h Pressure Coolant S stem (HPCIS) In ection S stem (HPCIS)

The HPCI system shall be 1. HPCI Subsystem testing OPERABLE whenever there is shall be performed as irradiated fuel in the follows:

reactor vessel and the reactor vessel pressure a. Simulated Once/18 is greater than 150 psig, Automatic months except as specified in Actuation Specification 3.5.E.2. Test OPERABILITY shall be determined within 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months b. Pump PER after reactor steam pressure OPERA- Specification reaches 150 psig from a COLD BILITY 1.0.MM CONDITION, or alternatively PRIOR TO STARTUP by using an c.. " Motor Oper- PER auxiliary steam supply. ated Valve Specification OPERABILITY 1.0.MM

d. Flow Rate at Once/3 normal months reactor vessel operating pressure BFN 3.5/4.5-13 Unit 3

3.5/4.5 CORE AND CONTAINMENT COOLING SYSTEMS LIMITING CONDITIONS FOR OPERATION SURVEILLANCE REQUIREMENTS 3.5.E Hi h Pressure Coolant In'ection 4;5.E Hi h Pressure Coolant In ection 4.5.E.l (Cont'd)

e. Flow Rate at Once/18 150 psig months The HPCI pump shall deliver at least 5000 gpm during each flow rate test.

2. If. the HPCI system is 2. Nhen it is determined that inoperable, the reactor may the HPCIS is inoperable the remain in operation for a ADS aci:uation logic, the period not to exceed 7 days, RCICS, '-the RHRS (LPCI), and provided the ADS, CSS, RHRS the CSS shall be (LPCI), and RCICS are demonstrated to be OPERABLE OPERABLE. immediately. The RCICS and ADS logic shall be demonstrated to be OPERABLE daily thereafter.

3. If Specifications 3.5.E.l or 3.5.E.2 are not met, an orderly shutdown shall be initiated and the reactor vessel pressure shall be reduced to 150 psig or less within 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months .

F. Reactor Core Isolation Coolin F. Reactor Core Isolation Coolin S stem (RCICS)

1. The RCICS shall be OPERABLE 1. RCIC Subsystem testing shall whenever there is irradiated be performed as follows:

fuel in the reactor vessel and the reactor vessel a. Simulated Once/18 month pressure is above 150 psig, Automatic except as specified in Actuation Test 3.5.F.2. OPERABILITY shall be determined within 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months b. Pump Per after reactor steam pressure OPERABILITY Specification reaches 150 psig from a COLD 1.0.MM CONDITION or alternatively prior to STARTUP by using an c; Motor-Operated Per auxiliary steam supply. Valve Specifi-OPERABILITY cation 1.0.MM BFN 3.5/4.5-14 Unit 3

3.5/4.5 CORE AND CONTAINMENT COOLING SYSTEMS LIMITING CONDITIONS FOR OPERATION SURVEILLANCE REQUI REMENTS 3.5.F Reactor Core Isolation Coolin 4.5.F Reactor Core Isolation Cool in 4.5.F.1 (Cont'd)

d. Flow Rate at Once/3 normal reactor months vessel operating pressure

e. Flow Rate at Once/18 150 psig months The RCIC pump shall deliver at least. 600 gpm during each flow test.

2. If the RCICS i s inoperable, 2. Hhen it is determined that the reactor may remain in the RCICS is inoperable, the operation for a period not HPCIS shall be demonstrated to exceed 7 days if the to be OPERABLE immediately.

HPCIS is OPERABLE during such time.

3. If Specifications 3.5.F.l or 3.5.F.2 are not met, an orderly shutdown shall be initiated and the reactor shall be depressurized to less than 150 psig within 24 hours.

G. Automatic De ressurization G. Automatic De ressurization

~5 S stem (ADS)

1. Four of the six valves of 1. During each operating the Automatic cycle the following Depressurization System tests shall be performed

" on shall be OPERABLE: the ADS:

(1) PRIOR TO STARTUP a. A simulated automatic from a COLD CONDITION, actuation test shall or, be performed prior to STARTUP after each BFN 3.5/4.5-15 Unit 3

BASES 3.5.E The HPCIS is provided to assure that the reactor core is adequately cooled to limit fuel clad temperature in the event of a small break in the nuclear system and loss of coolant which does not result in rapid depressurization of the reactor vessel. The HPCI system permits the reactor to be shut down while maintaining sufficient reactor vessel water level inventory until the vessel is depressuri'zed'. -The HPCIS continues to operate until reactor vessel pressure is below the pressure at which LPCI operation or Core Spray system operation maintains core cooling. The capacity of the system is selected to provide the required core cooling. The HPCI pump is designed to pump 5000 gpm at reactor pressures between 1120 and 150 psig. The HPCIS is not required to be operable below 150 psig since this is well within the range of the low pressure cooling systems and below the pressure of any events for which HPCI is required to provide core cooling.

The HPCIS is not designed to operate at full capacity 'unti 1 reactor pressure exceeds 150 psig and the steam supply to the HPCI turbine is automatically isolated before reactor pressure decreases below 100 psig. The ADS, CSS, and RHRS (LPCI) must be OPERABLE when starting up from a Cold Condition. Steam pressure is sufficient at 150 psig to run the HPCI turbine for operability testing, yet still below the shutoff head of the CSS and RHSfS pumps so they will inject water into the vessel if required. The ADS provides additional backup to reduce pressure to the range where the CSS and RHRS will inject into the vessel if necessary. Considering the low reactor pressure, the redundancy and availability of CSS, RHRS, and ADS during startup from a Cold Condition, twelve hours is allowed as a reasonable time to demonstrate HPCI operability once sufficient steam pressure becomes available'he alternative to demonstrate HPCI operability prior to startup using auxiliary steam is provided for plant operating flexibility.

With the HPCIS inoperable, a seven day period to return the system to service is justified based on the availability of'he ADS, CSS, RHRS (LPCI) and the RCICS.

The availability of these redundant and diversified systems provides adequate assurance of core cooling while HPCIS is out of service.

The surveillance requirements, which are based on industry codes and standards, provide adequate assurance that the HPCIS will be OPERABLE when required.

BFN 3.5/4.5-31 Unit 3

3.5 BASES (Cont'd) 3.5.F Reactor Core Isolation Coolin S stem (RCICS)

The RCICS functions to provide core cooling and makeup water to the reactor vessel during shutdown and isolation from the main heat sink and for certain pipe break accidents. The RCICS provides its design flow between 150 psig and 1120 psig reactor pressure. Below 150 psig, RCICS is not required to be operable since this pressure is substantially below that for any events in which RCICS is required to provide core cooling. RCICS will continue to operate below 150 psig at reduced flow until it automatically isolates at greater than or equal to 50 psig reactor steam pressure. 150 psig is also below the shutoff head of the CSS and RHRS, thus, considerable overlap exists with the cooling systems that provide core cooling at low reactor pressure.

The ADS, CSS, and RHRS (LPCI) must be OPERABLE 'when starting up from a Cold Condition. Steam pressure is sufficient at 150 psig to run the RCIC turbine for operability testing, yet still below the shutoff head

'of the CSS and RHRS pumps so they will inject water into the vessel if required. Considering the low reactor pressure and the availability of the low pressure coolant systems during startup from ia Cold Condition, twelve hours is allowed as a reasonable time to demonstrate RCIC operability once sufficient steam pressure becomes available. The alternative to demonstrate RCIC operability prior to startup using auxiliary steam is provided for plant operating flexibility.

Hith the RCICS inoperable, a seven day period to return the system to service is justified based on the availability of the HPCIS to cool the core and upon consideration that the average risk associated with failure of the RCICS to cool the core when required is not increased.

The surveillance requirements, which are based on industry codes and standards, provide adequate assurance that the RCICS will be OPERABLE when required.

3.5.G Automatic De ressurization S stem (ADS)

This specification ensures the operability of the ADS under all conditions for which the depressurization of the nuclear system is an essential response to station abnormalities.

The nuclear system pressure relief system provides automatic nuclear system depressurization for small breaks in the nuclear system so that the low-pressure coolant injection (LPCI) and the core spray subsystems can operate to protect the fuel barrier. Note that this specification applies only to the automatic feature of the pressure relief system.

Specification 3.6.D specifies the requirements for the pressure relief function of the valves. It is possible for any number of the valves assigned to the ADS to be incapable of performing their ADS functions because of instrumentation failures, yet be fully capable of performing their pressure relief function.

BFN 3.5/4.5-32 Unit 3

ENCLOSURE 2 DESCRIPTION AND JUSTIFICATION BROHNS FERRY NUCLEAR PLANT (BFN)

Reason for Change BFN unit 1, 2, and 3 technical specifications (TS) for the High Pressure Coolant Injection (HPCI) System and the Reactor Core Isolation Cooling (RCIC)

System are being revised as follows:

1. Revise TS 3.5.E.l and 3.5.F.l to require the HPCI and RCIC systems to be operable after the reactor vessel pressure reaches 150 psig.

2. Revise the associated Bases Sections 3.5.E and 3.5.F resulting from these changes.

3. Revise TS 4.5.E.l and 4.5.F.l to update surveillance testing

'requencies verbage to be consistent with other BFN TS.

Description and Justification for the Proposed Changes l.a. The existing TS 3.5.E.l. currently reads:

The HPCI system shall be OPERABLE:

(1) prior to startup from a Cold Condition; or (2) whenever there is irradiated fuel in the reactor vessel and the reactor pressure is greater than 122 psig, except as specified in specification 3.5.E.2.

Revise TS 3.5.E.l; to read as follows:

The HPCI system shall be OPERABLE whenever there is irradiated fuel in the reactor vessel and the reactor pressure is greater than 150 psig, except as specified in specification 3.5.E.2. OPERABILITY shall be determined within 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months after reactor steam pressure reaches 150 psig from a COLD CONDITION, or alternatively PRIOR TO STARTUP by using an auxiliary steam supply.

l.b. The existing TS 3.5.F.1.(l) currently reads:

The RCICS system shall be OPERABLE:

(1) prior to startup from a Cold Condition; or (2) whenever there is irradiated fuel in the reactor vessel and the reactor pressure is greater than 122 psig, except as specified in specification 3.5.F.2.

Revise TS 3.5.F.l. to read as follows:

The RCICS system shall be OPERABLE whenever there is irradiated fuel in the reactor vessel and the reactor pressure is greater than 150 psig, except as specified in specification 3.5.F.2. OPERABILITY shall be determined within 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months after reactor steam pressure reaches 150 psig from a COLD CONDITION, or alternatively PRIOR TO STARTUP by'sing an auxiliary steam supply.

Justification for Proposed TS changes The current TS require the HPCI/RCIC pumps to be operable when the reactor vessel pressure is greater than 122 psig. The proposed TS would change this requirement to demonstrate HPCI/RCIC operability after reactor vessel pressure reaches 150 psig. This change would bring the TS into conformance with the design capabilities of the HPCI and RCIC turbine/pump combinations as well as the analyzed accident/transient demands for these systems over the range of 150 to 1120 psig reactor pressure.

The accidents and operational transients for which these systems are required to provide core cooling are generally analyzed for occurrence at full reactor power and pressure. During these events, the HPCI/RCIC systems intended functions are to maintain adequate reactor vessel water level until reactor pressure decreases to the injection range of the Core Spray (CS) or Residual Heat Removal systems (Low Pressure Coolant Injection mode, (RHR/LPCI)). The CS/LPCI will inject reactor cooling water when the reactor vessel pressure is greater than 150 psig in addition to providing all reactor core cooling requirements for those conditions below 150 psig. The BFN Final Safety Analysis Report (FSAR) chapter 14 substantiates the performance of the HPCI and RCIC systems over the pressure range from 150 psig to 1120 psig for those events where HPCI/RCIC are required to perform their intended function. Both of these systems provide full design flow in this reactor steam range. Both of these pumps will continue to operate at a reduced flow below 150 psig until they automatically isolate due to low steam pressure. The HPCI isolation setpoint is > 100 psig and the RCIC is > 50 psig. The CS/LPCI will begin injecting into the vessel at approximately 230 psig and continue providing flow down to zero reactor pressure. This provides sufficient overlap with the HPCI/RCIC systems to ensure that adequate water inventory is provided to the reactor core below 150 psig.

The proposed TSs require that the HPCI/RCIC pumps be demonstrated operable within 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months after the reactor pressure has reached 150 psig. The HPCI/RCIC pumps are not designed to operate at full capacity until reactor pressure exceeds 150 psig. Additionally, BFN TSs require that the Automatic Depressurization System (ADS), Core Spray (CS), and LPCI systems be operable when starting up from a Cold Condition. Steam pressure is sufficient at 150 psig to run the HPCI/RCIC turbines for operability testing. This is still below the shutoff head of the CS and LPCI pumps so they will inject water into the vessel if required during this 12 hour1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months period until the HPCI/RCIC systems..are demonstrated to be operable. The ADS provides additional backup to reduce pressure to the range where the CS and LPCI will inject into the vessel if necessary.

Considering the low reactor pressure, the redundancy and availability of CS, LPCI, and ADS during startup from a Cold Condition, 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months is a reasonable time period to demonstrate HPCI/RCIC operability once sufficient steam pressure becomes available.

2. Revise the Bases section 3.5.E and 3.5.F as proposed in Enclosure 1 of this letter".

6 Justification for the Proposed TS Change Revisions to TS Bases sections 3.5.E. and 3.5.F convey the basis for not requiring HPCI and RCIC systems to be operable below 150 psig reactor steam pressure. Additions include justification for performing HPCI and RCIC operability tests after sufficient steam is available from the reactor. In addition, the language of these two sections are being editorially updated to ensure technical accuracy and improve readability.

3.a. Existing Surveillance requirements 4.5.E.l.a and e state:

a. Simulated Automatic once/ operating cycle Actuation Test

e. Flow Rate at 150 psig once/ opdrating cycle Revise surveillance requirements 4.5.E.l.a and e to read:

a. Simulated Automatic "once/ 18 months" Actuation Test

e. Flow Rate at 150 psig "once/ 18 months" 3.b. Existing surveillance requirements 4.5.F.l.a and e state:

a. Simulated Automatic once/ operating cycle Actuation Test

e. Flow Rate at 150 psig once/ operating cycle Revise surveillance requirements 4.5.F.l.a and e to read:

a. Simulated Automatic "once/ 18 months" Actuation Test

e. Flow Rate at 150 psig "once/ 18 months" Justification for the Proposed TS Changes:

Operating cycles extend from one refueling to the next. This operating cycle is usually expected to be 18 months in durations Longer operating cycles could result from operating at lower power levels, numerous reactor mini outages, and other extenuating circumstances. BFN TS 1.0.LL allows a maximum extension of a surveillance requirement not to exceed 25%%u of the surveillance interval. This would allow a maximum of 22.5 months to perform the above surveillances. Specifically, this time would be the period that the unit is shutdown (tripped) to start the refueling to just prior to startup for the subsequent cycle of operation as defined in BFN TS 1.0.D. It is unlikely that an operating cycle would exceed 22.5 months of continuous full power operation. Based on this, changing the surveillance interval to read once every 18 months is consistent with the other BFN TSs, industry practices, and NRC guidelines.

ENCLOSURE 3 DETERMINATION OF NO SIGNIFICANT HAZARDS CONSIDERATION BROHNS FERRY NUCLEAR PLANT (BFN)

UNITS 1, 2, AND 3 DESCRIPTION OF PROPOSED TS AMENDMENT BFN units 1, 2, and' technical specifications (TS) 3.5.E.l/4.5.E.l, 3.5.F.l/4 5.F-.l, .Bases section 3.5.E and 3.5.F are being revised. These revisions include:

1. demonstrating the HPCI/RCIC systems operability at 150 psig instead of the current 122 psig reactor vessel pressure.

2. updating the Bases sections 3.5.E and 3.5.F to reflect the changes made in item above and to better describe the characteristics of the 1

HPCI/RCIC systems.

3. update the surveillance testing frequencies for TS 4.5.E and 4.5.F to provide consistency with the BFN TS.

BASIS FOR PROPOSED NO SIGNIFICANT HAZARDS CONSIDERATION DETERMINATION NRC has provided standards for determining whether a si'gnificant hazards consideration exists as stated in 10 CFR 50.92(c). A proposed amendment to an operating license involves no significant hazards consideration if operation of the facility in accordance with the proposed amendment would not

1) involve a significant increase in the probability or consequences of an accident previously evaluated, or 2) create the possibility of a new or different kind of accident from an accident previously evaluated, or 3) involve a significant reduction in a margin of safety.

1. This proposed change does not involve a significant increase in the probability or consequences of an accident previously evaluated'he purpose amendment requires the HPCI/RCIC systems to be operable when reactor pressure is greater than 150 psig instead at 122 psig as currently stated in the TS. Additionally, this amendment allows demonstrating HPCI/RCIC operability within 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months after sufficient reactor steam pressure becomes available during a cold startup. This revision brings the BFN TS into technical agreement with the analyzed operating range and design specifications of the HPCI/RCIC HPCI and RCIC systems provide full design flow in the reactor systems'he pressure range of 150 to 1120 psig with their isolation setpoints >

100 psig and >50 psig reactor pressure respectively. The shutoff head for the Core Spray System and RHR/LPCI are 285 psig and 295 psig respectively. These low pressure coolant system's will begin injecting flow into the vessel at approximately 230 psig and continue providing adequate core cooling down to zero reactor pressure. Thus, it can be seen that there is considerable overlap with the HPCI/RCIC systems and the low pressure CS/LPCI systems before cutoff of the high pressure systems below 150 psig. Therefore the high pressure systems are not required to provide core cooling below 150 psig, Based on this, no adverse effects on safety are encountered in raising the operability requirements of the HPCI/RCIC systems from 122 psig to 150 psig.

0 Since there is an overlap between the high pressure injection systems and the low pressure injection systems, there is more than adequate core cooling capability to ensure that the reactor core remains covered as analyzed in the BFN Final Safety Analysis Report (FSAR).

Hith this overlap, allowing the reactor pressure to be at or above 150 psig for twelve hours while demonstrating the HPCI/RCIC systems to be operable, wi'll not increase the probability or consequences of an accident .as previously evaluated in the BFN FSAR.

'I Revising the surveillance requirements from once per operating cycle to once every 18 months provides consistency with other BFN TS, industry standard practices, and NRC guidelines. Using the + 25%%u allowed by TS, there could be a maximum of 22.5 months between surveillance tests. There are additional surveillance requirements that are performed at lesser frequencies which demonstrate pump operability. The simulated automatic actuation test and the pump flow rate at 150 psig are tested once per 18 months. The pump operability, and motor operated valve operability are tested in accordance with ASME section XI testing. In addition, the flow rate at normal reactor

'essel operating pressure is tested once per 3 months. Performance of these tests provides adequate assurance that the HPCI/RCIC systems will perform their intended function.

These proposed changes do not involve any physical alteration of the plant or add any new equipment which could be the source of a malfunction or accident. Based on the above, this proposed change does not involve a significant increase in the probability or consequence of an accident previously evaluated.

2. The proposed change does not create the possibility of a new or different kind of accident from an accident previously evaluated.

The proposed changes do not add any new equipment or require any existing equipment to operate outside its design specifications.

Operating BFN under the requirements of the proposed TS does not alter the function of any instrumentation, involve any type of modification to the plant, introduce a new or different release pathway of any radioactive material to the environment, or create any new modes of operation that have not previously been analyzed. Implementation of this proposed change is consistent with and remains within the bounds of the BFN FSAR analysis.

3. This proposed change does not involve a significant reduction in a margin of safety.

As stated above, there is considerable overlap with the high pressure HPCI/RCIC systems and the low pressure CS/LPCI systems before cutoff of the high pressure systems below 150 psig reactor pressure.

Therefore, HPCI/RCIC are not required to provide core cooling below 150 psig. Consequently, there. is no significant reduction in the margin of safety by raising the operability requirements from 122 psig to 150 psig. In addition, the plants operating flexibility is enhanced by providing the option, that is currently in the TS, to demonstrate HPCI/RCIC operability with auxiliary steam.

0 Considering the low reactor pressure, the redundancy and availability of the low pressure systems during startup from a Cold Condition, twelve hours is a reasonable time to demonstrate HPCI/RCIC operability once steam of sufficient pressure is available. This relatively short time frame will not create any significant increase in the risk associated with the unavailability of the HPCI/RCIC than has already been evaluated in the seven day out-of-service time that is typical industry .practice. Therefore, it is concluded that there will be no significant reduction in the margin of safety due to implementing these TS operability requirements.

Revising the surveillance frequency requirements is consistent with other BFN TS. BFN fuel is not designed to operate for 22.5 months at continuous full power operation. Changing the surveillance requirements to once every 18 months does not exceed the design limits nor change the intent of the existing TS.

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ML18033A880

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