Text

Proposed Tech Specs Modifying Reactor Coolant Sys Vent Size Required for Overpressure Protection Operation
	ML20086H002
Person / Time
Site:	Beaver Valley
Issue date:	07/11/1995
From:	; DUQUESNE LIGHT CO.
To:	;
Shared Package
ML20086G995	List: ML20086G992; ML20086H002;
References
	NUDOCS 9507170371
	Download: ML20086H002 (23)
	v • d • e

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DPR-66

.. REACTIVITY CONTROL SYSTEMS 3/4.1.2 BORATION SYSTEMS FLOW PATHS - SHUTDOWN LIMITING CONDITION FOR OPERATION 3.1.2.1 As a minimum, one of the following boron injection flow paths shall be OPERABLE:

a. A flow path from the boric acid storage system via a boric acid transfer pump to a charging pump to the Reactor Coolant System if only the boric acid storage tank in Specification 3.1.2.7.a is OPERABLE, or g

b. The flow path from the refueling water storage ank via a charging pump or a low head safety injection pump (with an open RCS vent of greater than or equal to square l inches) to the Reactor Coolant System if only the refueling water storage tank in Specification 3.1.2.7.b is OPERABLE.

APPLICABILITY: MODES 5 and 6, ACTION:

With none of the above flow paths OPERABLE, suspend all operations involving CORE ALTERATIONS or positive reactivity changes until at least one injection path is restored to OPERABLE status.

SURVEILLANCE REQUIREMENTS 4.1.2.1 At least one of the above required flow paths shall be demonstrated OPERABLE:

i a. At least once per 7 days by:

1. Cycling each testable power operated or automatic

valve in the flow path throygh at least one complete

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j cycle of full travel.

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! BEAVER VALLEY - UNIT 1 3 1-7 Amendment No.

(Mo/4Posen vothin')

9507170371 950711 PDR ADDCK 05000334 P PDR

(

DPR-66 REACTIVITY CONTROL SYSTEMS

.CMARGING PUMP - SHUTDOWN LIMITING CONDITION FOR OPERATION 1

3.1.2.3 At least one charging pump" in the boron injection '

flow path required by Specification 3.1.2.1 or low head safety injection pump (with an open reactor coolant system vent of greater than or equal to f rH- square inches) shall be OPERABLE and capable 1 of being poweredffrom an OPERABLE bus.

20' APPLICABILITY: ES 5 and 6.

ACTION:

With none of the above pumps OPERABLE, suspend all operations involving CORE ALTERATIONS or positive reactivity changes until one charging pump or low head safoty injection pump is restored to OPERABLE status.

SURVEILLANCE REQUIREMENTS 4.1.2.3.1 The above required charging pump shall be demonstrated OPERABLE by verifying, on recirculation flow, that the pump develops a discharge pressure greater than or equal to 2402 psig when tested pursuant to Specification 4.0.5.

4.1.2.3.2 When the low head safety injection pump is used in lieu of a charging pump, the low head safety injection pump shall be demonstrated OPERABLE by:

a. Verification of an operable RWST pursuant to 4.1.2.7,

b. Verification of an operable low head safety injection pump pursuant to specification 4.5.7.b.2,

c. Verification of an operable low head safety injection flow path from the RWST to the Reactor Coolant System once per shift, and

d. Verification that the vent is open in accordance with 4.4.9.3.3.

(1) With two charging pumps OPERABLE, follow Specification 3.4.9.3.

4 BEAVER VALLEY - UNIT 1 3/4 2-11 Amendment No.

Y hfoS Y Yo No 0

4 DPR-66 REACTOR COOLANT SYSTEM OVERPRESSURE PROTECTION SYSTEMS LIMITING CONDITION FOR OPERATION l

3.4.9.3 An overpressure protection system shall be OPERABLE with a maximum of one charging pump"' capable of injecting into the RCS and the accumulators isolated" and either a or b below:

a. Two power operated relief valves (PORVs) with a lift setting less than or equal to 432 psig, or

b. The RCS depressurized and an RCS vent of greater than or equal to square inches. l APPLICABILITY: ' e 4 when any RCS cold leg temperature is less than or equal to an enable temperature of 329'F, Mode 5, Mode 6 when the reactor vessel head is on.

ACTION:

a. With two or more charging pumps capable of injecting into the RCS, immediately initiate action to verify a maximum of one charging pump is capable of injecting into the RCS or depressurize and vent the RCS through a '.14 square inch or I larger vent within 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months .

b. With an accumulator not isolated when the accumulator pressure is greater than or equal to the maximum RCS pressure for the existing RCS cold leg temperature allowed by the heatup and cooldown curves, isolate the affected accumulator within 1 hour1.157407e-5 days 2.777778e-4 hours 1.653439e-6 weeks 3.805e-7 months or increase the RCS cold leg temperature above the enable temperature within the next 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months or depressurize the affected accumulator to less

, than the maximum RCS pressure for the existing cold leg

temperature allowed by the heatup and cooldown curves l within the next 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months .

c. With one PORV inoperable in MODE 4 (when any RCS cold leg

temperature is less than or equal to the enable temperature), restore the inoperable PORV to OPERABLE status within 7 days or depressurize and vent the RCS

through a . square inch or larger vent within the next 1 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months . 4 07

'. (1) Two charging pumps may be capable of injecting into the RCS for pump swap operation for less than or equal to 15 minutes.

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(2) Accumulator isolation with power removed from the discharge isolation valves is only required when the accumulator pressure is greater than or equal to the maximum RCS pressure for the existing RCS cold leg temperature' allowed by the heatup and cooldown curves.

BEAVER VALLEY - UNIT 1 3/4 4-27a Amendment No.

(fMpos & &h*clo 1

l

.. DPR-66

. REACTOR COOLANT SYSTEM LIMITING CONDITION FOR OPERATION (Continued)

ACTION: (Continued)

d. With one PORV inoperable in MODES 5 or 6, restore the I inoperable PORV to OPERABLE status within 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months or depressurize and vent the RCS through a square inch or l larger vent within the next 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months . ,07

e. With two PORVs inoperable, depressurize and vent the RCS through a square inch or larger vent within 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months . l SURVEILLANCE REQUIREMENTS 4.4.9.3.1 Verify at least once per 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months that:

a. A maximum of one charging pump is capable of injecting into !

the RCS, and i

b. Each accumulator is isolated; however, with the accumulator pressure less than the low temperature overpressure protection setpoint, the accumulator discharge isolation valves may be opened to perform accumulator discharge check i valve testing. l i

4.4.9.3.2 When PT8tVs are being used for overpressure protection, I demonstrate each PCPV is OPERABLE by:

a. Verifying each PORV block valve is open for each required PORV at least once per 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months , and

b. Performance of a CHANNEL FUNCTIONAL TEST on the PORV !

actuation channel, but excluding valve operation, within .

i 31 days prior to entering a condition in which the PORV is l required to be OPERABLE and placed in operation after decreasing the RCS cold leg temperature to less than or equal to the enable temperature and at least once per 31 !

days, and

c. Performance of a CHANNEL CALIBRATION on each required PORV -

actuation channel at least once per 18 months. !

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1 BEAVER VALLEY - UNIT 1 3/4 4-27b Amendment No. ;

(frofosed 100t'N l

'DPR-66 REACTIVITY CONTROL SYSTEMS BASES 3/4.1.1.4 MODERATOR TEMPERATURE COEFFICIENT (MTC) (Continued) fuel cycle. The surveillance requirement for measurement of the MTC at the beginning and near the and of each fuel cycle is adequate to confirm the MTC value since this coefficient changes slowly due principally to the reduction in RCS boron concentration associated with fuel burnup.

3/4.1.1.5 MINIMUM TEMPERATURE FOR CRITICALITY This specification ensures that the reactor will not be made critical with the Reactor Coolant System average temperature less !

than 541*F. This limitation is required to ensure (1) the moderator temperature coefficient is within its analyzed temperature range, (2) the pressurizer is capable of being in an OPERABLE status with a steam bubble, (3) the reactor pressure vessel is above its minimum RTNDT temperature, and (4) the protective instrumentation is within :

its normal operating range.

3/4.1.2 pORATION SYSTEMS The boron injection system ensures that negative reactivity control r is available during each mode of facility operation. The components required to perform this function include (1) borated water sources, (2) charging pumps, (3) separate flow paths, (4) boric acid transfer pumps, (5? associated heat tracing systems, and (6) an emergency '

power sur: ty from OPERABLE diesel generators.

With the RCS average temperature above 200*F, a minimum of two separate and redundant boron injection systems are provided to ensure single functional capability in the event an assumed failure renders one of the systems inoperable. Allowable out-of-service periods ensure that minor component repair or corrective action may be completed without undue risk to overall facility safety from injection system failures during the repair per .

2.07 With the RCS average temperature less tha F, a Low Head Safety ,

Injection pump may be used in lieu of the operable charging pump l l with a minimum open RCS vent of 3.10 square inches. This will l

provide latitude for maintenance and ISI examinations on the l

! charging system for repair or corrective action and will ensure that ,

boration and makeup are available when the charging pumps are out-of-service. An open vent ensures that the RCS pressure will not exceed the- shutoff head of the Low Head Safety Injection pumps.

MOV-lSI-890C is the Low Head Safety Injection Pump discharge isolation valve to the RCS coldlegs, the valve must be closed prior i to reducing RCS pressure below the RWST head pressure to prevent

) draining into the RCS. Emergency backup power is not required since this valve is outside containment and can be manually operated if required, this will allow the associated diesel generator to be taken out of service for maintenance and testing.

BEAVER VALLEY - UNIT 1 B 3/4 1-2 Amendment no. 112 i i

(froposed Nord)

DPR-66 REACTOR COOLANT SYSTEM l BASES (Continued)

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3/4.4.9 PRFMSURE/ TEMPERATURE LTMITS (Continuedi HEAT INPUT TYPE TRANSIENTS (Continued) j c. Disallowing start of an RCP if secondary temperature is more i than 25"F above primary temperature in any one loop. LCO 3.4.1.6, " Reactor Coolant Pump Startup," provides this protection.

l The analyses demonstrate that either one RCS relief valve or the

! depressurized RCS and RCS vent can maintain the RCS pressure below the limits when only one charging pump is actuated by SI. Thus, the LCO allows only one charging pump OPERABLE during the OPPS MODES.

lj Since neither one RCS relief valve nor the RCS vent can handle a full SI actuation, the LCO also requires the accumulators isolated.

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! The isolated accumulators must have their discharge valves closed j with power removed. Fracture mechanics analyses established the q temperature of OPPS Applicability at the enable temperature.

l PORV PERFORMANCE 1

The fracture mechanics analyses show that the vessel is protected i when the PORVs are set to open at or below the limit. The setpoint l is derived by analyses that model the performance of the , OPPS i j assuming the limiting OPPS transient of SI actuation of one charging

pump. These analyses consider pressure overshoot and undershoot

! beyond the PORV opening and closing, resulting from signal processing l and valve stroke times. The PORV setpoints at or below the derived l

limit ensures the P/T limits will be met.

The PORV setpoint will be updated when the revised P/T limits conflict with the OPPS analysis limits. The P/T limits are

! periodically modified as the reactor vessel material toughness i decreases due to neutron embrittlement caused by neutron irradiation.

l Ravised limits are determined using neutron fluence projections and i

the results of examinations of the reactor vessel material i irradiation surveillance specimens. The Bases for LCO 3.4.9.1,'

l " Pressure / Temperature Limits," discuss these examinations.

l 1 The PORVs are considered active components. Thus, the failure of one i PORV is assumed to represent the worst case, single active failure.

)

2 RCS VENT PERFORMANCE j ,2 ,0'7 j With the RCS depressurized, analyses show that a PORV or equivalent i opening with a vent size of . square inches is capable of l j mitigating the allowed OPPS overpressure transient. The capacity of i.

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. BEAVER VALLEY - UNIT 1 p 3/4 Amendment No.

Dtfds'6l4-10 eof): )

l DPR-66 REACTOR COOLANT SYSTEM BASES (Continued) 3/4.4.9 PRESSURE / TEMPERATURE LIMITS (Centinuedi LC.Q (Continued) g l

1 An RCS vent is OPERABLE when open with an area of +r44- square inches. l i

I Each of these methods of overpressure prevention is capable o f. l mitigating the limiting OPPS transient.

APPLICABILITY This LCO is applicable in MODE 4 when any RCS cold leg temperature is less than or equal to the enable temperature, in MODE 5, and in MODE 6 when the reactor vessel head is on. When the reactor vessel head is off, overpressurization cannot occur.

Low temperature overpressure prevention is most critical during shutdown when the RCS is water solid, and a mass or heat input transient can cause a very rapid increase in RCS pressure when little or no time allows operator action to mitigate the event.

ACTION I

a. With two or more charging pumps capable of injecting into the RCS, RCS overpressurization is possible.

To immediately initiate action to restore restricted coolant input capability to the RCS reflects the urgency of removing the RCS from this condition.

b. An unisolated accumulator requires isolation within 1 hour1.157407e-5 days 2.777778e-4 hours 1.653439e-6 weeks 3.805e-7 months .

This is only required when the accumulator pressure is at or more than the maximum RCS pressure for the existing temperature allowed by the P/T limit curves.

If isolation is needed and cannot be accomplished in 1 hour1.157407e-5 days 2.777778e-4 hours 1.653439e-6 weeks 3.805e-7 months , the ACTION provides two options, either of which must be performed in the next 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months . By increasing the RCS temperature to more than the enable temperature, the accumulator pressure cannot exceed the OPPS limits if the accumulators are fully injected. Depressurizing the accumulators below the OPPS limit also gives this protection.

The completion times are based on operating experience that these activities can be accomplished in these time periods indicating that an event requiring OPPS is not likely in the allowed times.

BEAVER VALLEY - UNIT 1 B 2/4 4-10g Amendment No.

(frefek$ LU0thNp

DPR-66

, , REACTOR COOLANT SYSTEM BASES (Continued) 3/4.4.9 PREESURE/ TEMPERATURE LIMITS (Continuadi l

ACTION (Continued)

c. In MODE 4 when any RCS cold leg temperature is less than or equal to the enable temperature, with one required RCS relief valve inoperable, the RCS relief valve must be restored to OPERABLE status within a completion time of 7 days. Two RCS relief valves are required to provide low temperature overpressure mitigation while withstanding a single failure of an active component.

The completion time considers the facts that only one of the RCS relief valves is required to mitigate an overpressure transient and that the likelihood of an active failure of the remaining valve path during this time period is very low. If plant operation results in transitioning to MODE 5, the completion time to restore an inoperable PORV may not exceed 7 days as required by this ACTION.

d. The consequences of operational events that will overpressurize the RCS are more severe a t- lower temperature. Thus, with one of the two RCS relief valves inoperable in MODE 5 or in MODE 6 with the head on, the completion time to restore two valves to OPERABLE status is 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months .

The completion time represents a reasonable time to investigate and repair several types of relief valve failures without exposure to a lengthy period with only one OPERABLE RCS relief valve to protect against overpressure events. If a PORV is inoperable when the plant enters MODE 5 from MODE 4, the completion time to restore an inoperable PORV changes to 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months but the cumulative inoperable time may not exceed 7 days before taking action to depressurize and nt.

f>0

e. The RCS must be apressurized and a vent must be established within 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months when both required RCS relief valves are inoper le. The vent must be sized greater than or equal to 0.1, square inches to ensure that the flow I capacity is greater than that required for the worst case mass input transient reasonable during the applicable MODES. This action is needed to protect the RCPB from a i low temperature overpressure event and a possible brittle failure of the reactor vessel.

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l BEAVER VALLEY - UNIT 1 B 3/4 4-10h Anendsent No.

0%poscd Wordiy) 1

l DPR-66 i

. REACTOR COOLANT SYSTEM BASES (Continued) j t

j 3/4.4.9 PRFRSURE/ TEMPERATURE LIMITS (Continued) ;

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SURVETTr.ANCE REQUIREMENTS (SR) (Continued) i l The SR is required to be performed prior to entering the condition

! for the OPPS to be OPERABLE. This assures low temperature j overpressure protection is available when the RCS cold leg temperature is less than or equal to the enable temperature. ,

! Performing the surveillance every 31 days on each required PORV ,

I permits verification and adjustment, if necessary, of its lift l i

setpoint, and considers instrumentation reliability which has been shown through operating experience to be acceptable. The CHANNEL

, FUNCTIONAL TEST will verify the setpoint is within the allowed maximum limits. PORV actuation could depressurize the RCS and is not required.

Performance of a CHANNEL CALIBRATION on each required PORV actuation ,

i channel is required every 18 months to adjust the whole channel so that it responds and the valve opens within the required range and accuracy to known input.

SR 4.4.9.3.3 7 1 ,

The RCS vent of greater than or equal to -art 4-square inches is proven l l OPERABLE by verifying its open condition either:

a. Once every 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months for an open vent or valve that cannot be locked, except

b. Once every 31 days for a valve that is locked, or provided ,

with remote position indication, or sealed, or secured in position. A removed pressurizer safety valve fits this category.

The passive vent arrangement must only be open to be OPERABLE. This surveillance is required to be performed if the vant is being used to 4 satisfy the pressure relief requirements of the LCO. i l

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1 BEAVER VALLEY - UNIT 1 B 3/4 4-10j Amendment No. !

orc (CSed Word )

t ATTACHMENT B Beaver Valley Power Station, Unit No. 1 Proposed Technical Specification Change No. 222 REVISION TO OVERPRESSURE PROTECTION VENT SIZE A. DESCRIPTION OF AMENDMENT REQUEST The proposed amendment would modify the Reactor Coolant System (RCS) vent size stated in Specification 3.4.9.3, associated specifications and bases.

B. BACKGROUND The RCS overpressure protection system (OPPS) vent size is based on the size of a power operated relief valve (PORV) since a single PORV is analyzed to provide the required venting capacity. Based on a review of vendor supplied information for the PORVs, it was determined that the actual port diameter of these valves is 1.625 inches which provides a 2.07 square inch vent. The current vent size stated in the OPPS technical specification is based on a 2 inch port size which provides a 3.14 square inch vent.

C. JUSTIFICATION The proposed change replaces the 3.14 square inch vent size stated in OPPS Specification 3.4.9.3 and associated specifications and bases with a 2.07 square inch vent size.

This ensures the vent size stated in the technical specifications is consistent with analysis assumptions and with the actual size of a PORV port.

D. SAFETY ANALYSIS The RCS vent size stated in Specification 3.4.9.3.b, Actions "a," "c," "d," and "e," Specification 3.1.2.1.b and 3.1.2.3, and Bases 3/4.1.2 and 3/4.4.9 has been changed to

, reflect the actual port diameter of the PORVs. With the RCS depressurized, analyses show that a PORV or equivalent opening with a vent size of 2.07 square inches is capable of mitigating the expected OPPS overpressure transients.

The flow capacity through a vent this size is greater than the flow of the limiting transient for the OPPS configuration.

This is considered an editorial change since it was not necessary to re-analyze for cold overpressure transients on the RCS but rather to verify the adequacy of the existing I analysis. These changes maintain consistency with the !

analyses assumptions and the operation of the PORVs in I accordance with applicable analyses and the UFSAR.

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i A.TTACHMENT B, continued Proposed Technical Specification Change No. 222 1

, Page 2 Therefore, these changes have been determined to be safe and will not reduce the safety of the plant.

E. NO SIGNIFICANT HAZARDS EVALUATION The no significant hazard considerations involved with the proposed amendment have been evaluated, focusing on the three standards set forth in 10 CFR 50.92(c) as quoted below:

The Commission may make a final determination, pursuant to the procedures in paragraph 50.91, that a proposed amendment to an operating license for a facility licensed under paragraph 50.21(b) or paragraph 50.22 or for a testing facility 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 l evaluated; or (2) Create the possibility of a new or different kind of accident from any accident previously evaluated; or (3) Involve a significant reduction in a margin of safety.

l The following evaluation is provided for the no significant l

hazards consideration standards.

1. Does the change involve a significant increase in the probability or consequences of an accident previously evaluated?

The proposed change is considered to be editorial since it replaces the 3.14 square inch vent size stated in overpressure protection system (OPPS) Specifications 3.4.9.3, 3.1.2.1.b, and 3.1.2.3 and Bases 3/4.1.2 and 3/4.4.9 with a 2.07 square inch vent size. This ensures the vent size stated in the technical specifications is consistent with the actual size of an installed PORV. These changes maintain consistency with the analyses assumptions and the operation of the OPPS in accordance with applicable analyses and the UFSAR. Therefore, we have concluded that these changes do not involve a significant increase in the probability or consequences of an accident previously evaluated in the UFSAR.

B-2

.. ATTACHMENT B, continutd P'roposed Technical Specification Change No. 222

. Page 3.

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2. Does the change create the possibility of a new~ or different kind of accident from any accident previously l evaluated') :

i The proposed changes do not involve any physical t changes to the OPPS or their setpoints. These changes e do not change any function previously provided by the OPPS. These changes do not affect any failure modes l defined for any plant system or component important to safety nor has any new limiting single failure been identified as a result of these changes. Therefore, these changes will not create the possibility of a new or- different kind of accident from any accident previously evaluated in the UFSAR.

t

3. Does the change involve a significant reduccion in a '

margin of safety? j The proposed changes will not affect the operation of ;

or the reliability of the OPPS. These changes do not l affect the manner in which the plant is operated or involve a change to equipment or features that affect the operational characteristics of the plant. i Therefore, operation of the plant in accordance with -

the proposed amendment would not involve a significant reduction in a margin of safety.

I F. NO SIGNIFICANT HAZARDS CONSIDERATION DETERMINATION j Based on the considerations expressed above, it is f concluded that the activities associated with this license ;

amendment request satisfies the no significant hazards j consideration standards of 10 CFR 50.92(c) and, accordingly, a no significant hazards consideration finding is justified.

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ATTACHMENT C

Beaver Valley Power Station, Unit No. 1 2

5 Proposed Technical Specification Change No. 222 1

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j Applicable Typed Pages I

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ATTACHMENT TO LICENSE AMENDMENT NO.

FACILITY OPERATING LICENSE NO. DPR-66 DOCKET NO. 50-334 l

l Replace the following pages of Appendix A, Technical Specifications,

with the enclosed pages as indicated. The revised pages are identified j by amendment number and contain vertical lines indicating the areas of 2

change.

1 E_emove Insert

3/4 1-7 3/4 1-7 3/4 1-11 3/4 1-11 j 3/4 4-27a 3/4 4-27a 3/4 4-27b 3/4 4-27b 4

B 3/4 1-2 B 3/4 1-2

} B 3/4 4-10e B 3/4 4-10e B 3/4 4-10g B 3/4 4-10g 3 B 3/4 4-10h B 3/4 4-10h B 3/4 4-10j B 3/4 4-10j i

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I (Proposed Wording) i

'm'y ,u-* - , - p--*y-++=

DPR-66 REACTIVITY CONTROL SYSTEMS 3/4.1.2 BORATION SYSTEMS FLOW PATHS - SHUTDOWN LIMITING CONDITION FOR OPERATION 3.1.2.1 As a minimum, one of the following boron injection flow paths shall be OPERABLE:

a. A flow path from the boric acid storage system via a boric acid transfer pump to a charging pump to the Reactor Coolant System if only the boric acid storage tank in Specification 3.1.2.7.a is OPERABLE, or

b. The flow path from the refueling water storage tank via a charging pump or a low head safety injection pump (with an open RCS vent of greater than or equal to 2.07 square l inches) to the Reactor Coolant System if only the refueling water storage tank in Specification 3.1.2.7.b is OPERABLE. ,

l APPLICABILITY: MODES 5 and 6.

ACTION:

With none ~of the above flow paths OPERABLE, suspend all operations involving CORE ALTERATIONS or positive reactivity changes until at least one injection path is restored to OPERABLE status.

SURVEILLANCE REQUIREMENTS 4 4.1.2.1 At least one of the above required flow paths shall be demonstrsted OPERABLE:

I

a. At least once per 7 days by:

1. Cycling each testable power operated or automatic l valve in the flow path through at least one complete

cycle of full travel.

a J

BEAVER VALLEY - UNIT 1 3/4 1-7 Amendment No.

(Proposed Wording)

,DPR-66 REACTIVITY CONTROL SYSTEMS CHARGING PUMP - SHUTDOWE LIMITING CONDITION FOR OPERATION 3.1.2.3 At least one charging pump (l) in the boron injection flow path required by Specification 3.1.2.1 or low head safety injection pump (with an open reactor coolant system vent of greater than or equal to 2.07 square inches) shall be OPERABLE and capable l of being powered from an OPERABLE bus.

APPLICABILITY: MODES 5 and 6.

ACTION:

With none of the above pumps OPERABLE, suspend all operations involving CORE ALTERATIONS or positive reactivity changes until one charging pump or low head safety injection pump is restored to OPERABLE status.

SURVEILLANCE REQUIREMENTS 4.1.2.3.1 The above required charging pump shall be demonstrated OPERABLE by verifying, on recirculation flow, that the pump develops a discharge pressure greater than or equal to 2402 psig when tested pursuant to specification 4.0.5.

4.1.2.3.2 When the low head safety injection pump is used in lieu of a charging pump, the low head safety injection pump shall be demonstrated OPERABLE by:

a. Verification of an operable RWST pursuant to 4.1.2.7,

b. Verification of an operable low head safety injection pump pursuant to Specification 4.5.2.b.2,

c. Verification of an operable low head safety injection flow path from the RWST to the Reactor Coolant System once per shift, and

d. Verification that the vent is open in accordance with 4.4.9.3.3.

(1) With two charging pumps OPERABLE, follow Specification 3.4.9.3. ,

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1 BEAVER VALLEY - UNIT 1 3/4 1-11 Amendment No.

(Proposed Wording) i

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DPR-66 REACTOR COOLANT SYSTEM OVERPRESSURE PROTECTION SYSTEMS LIMITING CONDITION FOR OPERATION 3.4.9.3 An overpressure protection system shall be OPERABLE with a maximum of one charging pump (1) capable of injecting into the RCS .

and the accumulators isolated (2) and either a or b below: l

a. Two power operated relief valves (PORVs) with a lift setting less than or equal to 432 psig, or

b. The RCS depressurized and an RCS vent of greater than or equal to 2.07 square inches. l !

APPLICABILITY: Mode 4 when any RCS cold leg temperature is less than or equal to an enable temperature of 329 F, Mode 5, Mode 6 when the reactor vessel head is on.

ACTION: ;

a. With two or more charging pumps capable of injecting into the RCS, immediately initiate action to verify a maximum of ;

one charging pump is capable of injecting into the RCS or ,

depressurize and vent the RCS through a 2.07 square inch or i larger vent within 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months .

b. With an accumulator not isolated when the accumulator pressure is greater than or equal to the maximum RCS pressure for the existing RCS cold leg temperature allowed by the heatup and cooldown curves, isolate the affected accumulator within 1 hour1.157407e-5 days 2.777778e-4 hours 1.653439e-6 weeks 3.805e-7 months or increase the RCS cold leg temperature above the enable temperature within the next 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months or depressurize the affected accumulator to less than the maximum RCS pressure for the existing cold leg temperature allowed by the heatup and cooldown curves within the next 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months .

c. With one PORV inoperable in MODE 4 (when any RCS cold leg temperature is less than or equal to the enable temperature), restore the inoperable PORV to OPERABLE status within 7 days or depressurize and vent the RCS through a 2.07 square inch or larger vent within the next i 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months .

(1) Two charging pumps may be capable of injecting into the RCS for pump swap operation for less than or equal to 15 minutes.

(2) Accumulator isolation with power removed from the discharge isolation valves is only required when the accumulator pressure is greater than or equal to the maximum RCS pressure for the ,

existing RCS cold leg temperature allowed by the heatup and I cooldown curves.

)

1 BEAVER VALLEY - UNIT 1 3/4 4-27a Amendment No. l (Proposed Wording) l

. . _ . _ . - - _ _ . _ _ _ _ . _ _ . _ . _ .. . - . . _ . . - - . _ ~

DPR-66 REACTOR COOLANT SYSTEM

{ LIMITING CONDITION FOR OPERATION (Continued) i ACTION: (Continued)

)

d. With one PORV inoperable in MODES 5 or 6, restore the

! inoperable PORV to OPERABLE status within 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months or

! depressurize and vent the RCS through a 2.07 square inch or l l larger vent within the next 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months .

e. With two PORVs inoperable, depressurize and vent the RCS through a 2.07 square inch or larger vent within 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months . l SURVEILLANCE REQUIREMENTS 4.4.9.3.1 Verify at least once per 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months that:

a. A maximum of one charging pump is capable of injecting into the RCS, and

b. Each accumulator is isolated; however, with the accumulator pressure less than the low temperature overpressure protection setpoint, the accumulator discharge isolation valves may be opened to perform accumulator discharge check valve testing.

4.4.9.3.2 When PORVs are being used for overpressure protection, demonstrate each PORV is OPERABLE by:

a. Verifying each PORV block valve is open for each required PORV at least once per 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months , and

b. Performance of a CHANNEL FUNCTIONAL TEST on the PORV actuation channel, but excluding valve operation, within 31 days prior to entering a condition in which the PORV is required to be OPERABLE and placed in operation after decreasing the RCS cold leg temperature to less than or equal to the enable temperature and at least once per 31 days, and i

c. Performance of a CHANNEL CALIBRATION on each required PORV actuation channel at least once per 18 months.

BEAVER VALLEY - UNIT 1 3/4 4-27b Amendment No.

- (Proposed Wording) -

i !

. pPR-66 i

REACTIVITY CONTROL SYSTEMS BASES 3/4.1.1.4 MODERATOR TEMPERATURE COEFFICIENT (MTC) (Continued) 4 i fuel cycle. The surveillance requirement for measurement of the MTC t

at the beginning and near the end of each fuel cycle is adequate to

confirm the MTC value since this coefficient changes slowly due l_ principally to the reduction in RCS boron concentration associated j with fuel burnup.

} 3/4.1.1.5 MINIMUM TEMPERATURE FOR CRITICALITY !

This specification ensures that the _ reactor will not be made

! critical with the Reactor Coolant System average temperature less

! than 541 F. This limitation is required to ensure (1) the moderator

! temperature coefficient is within its analyzed temperature range,

(2) the pressurizer is capable of being in an OPERABLE status with a ,

j steam bubble, (3) the reactor pressure vessel is above its minimum ,

j. RTNDT temperature, and (4) the protective instrumentation is within its normal operating range.

3/4.1.2 BORATION SYSTEMS

The boron injection system ensures that negative reactivity control l is available during each mode of facility operation. The components

! required to perform this function include (1) borated water sources,

! (2) charging pumps, (3) separate flow paths, (4) boric acid transfer

! pumps, (5) associated heat tracing systems, and (6) an emergency l power supply from OPERABLE diesel generators.

With the RCS average temperature above 2 0 0*F , a minimum of two ,

i separate and redundant boron injection systems are provided to l ensure single functional capability in the event an assumed failure '

renders one of the systems inoperable. Allowable out-of-service I periods ensure that minor component repair or corrective action may

be completed without undue risk to overall facility safety from i injection system failures during the repair period.

With the RCS average temperature less than 200*F, a Low Head Safety l

Injection pump may be used in lieu of the operable charging pump i with a minimum open RCS vent of 2.07 square inches. This will l l

provide latitude for maintenance and ISI examinations on the t charging system for repair or corrective action and will ensure that l boration and makeup are available when the charging pumps are out-

. of-service. An open vent ensures that the RCS pressure will not exceed the shutoff head of the Low Head Safety Injection pumps.

{

I MOV-1SI-890C is the Low Head Safety Injection Pump discharge

isolation valve to the RCS coldlegs, the valve must be closed prior to reducing RCS pressure below the RWST head pressure to prevent draining into the RCS. Emergency backup power is not required since l" this valve is outside containment and can be manually operated if required, this will allow the associated diesel generator to be taken out of service for maintenance and testing.

{

1 BEAVER VALLEY.- UNIT 1 B 3/4 1-2 Amendment No.

(Proposed Wording)

I i

f**

4 l

DPR-66 REACTOR COOLANT SYSTEM J

BASES (Continued) i

} 3/4.4.9 PRESSURE / TEMPERATURE LIMITS (Continued) l 4 l i HEAT INPUT TYPE TRANSIENTS (Continued) !

1 j c. Disallowing start of an RCP if secondary temperature is j j more than 25 F above primary temperature in any one loop.

i LCO 3.4.1.6, " Reactor Coolant Pump Startup," provides this !

j protection. l The analyses demonstrate that either one RCS relief valve or the !

l depressurized RCS and RCS vent can maintain the RCS pressure below j the limits when only one charging pump is actuated by SI. Thus, the 1

! LCO allows only one charging pump OPERABLE during the OPPS MODES.

1 Since neither one RCS relief valve nor the RCS vent can handle a '

! full SI actuation, the LCO also requires the accumulators isolated.

, The isolated accumulators must have their discharge valves closed i j with power removed. Fracture mechanics analyses established the i temperature of OPPS Applicability at the enable temperature.

! PORV PERFORMANCE j l The fracture mechanics analyses show that the vessel is protected '

j when the PORVs are set to open at or below the limit. The setpoint l is derived by analyses that model the performance of the OPPS assuming the limiting OPPS transient of SI actuation of one charging pump. These analyses consider pressure overshoot and undershoot

beyond the PORV opening and closing, resulting from signal !

processing and valve stroke times. The PORV setpoints at or below l l the derived limit ensures the P/T limits will be met.

i l The PORV setpoint will be updated when the revised P/T limits j conflict with the OPPS analysis limits. The P/T limits are

! periodically modified as the reactor vessel material toughness i decreases due to neutron embrittlement caused by neutron i irradiation. Revised limits are determined using neutron fluence i projections and the results of examinations of the reactor vessel

' material irradiation surveillance specimens. The Bases for LCO

{ 3.4.9.1, " Pressure / Temperature Limits," discuss these examinations.

1 The PORVs are considered active components. Thus, the failure of

{ one PORV is assumed to represent the worst case, single active failure.

l 1

RCS VENT PERFORMANCE With the RCS depressurized, analyses show that a PORV or equivalent

! opening with a vent size of 2.07 square inches is capable of I

mitigating the allowed OPPS overpressure transient. The capacity of p

i- BEAVER VALLEY - UNIT 1 B 3/4 4-10e Amendment No.

l (Proposed Wording) 1

- .DPR-66 REACTOR COOLANT SYSTEM BASES (Continued) 3/4.4.9 PRESSURE / TEMPERATURE LIMITS (Continued)

LCQ (Continued)

An RCS vent is OPERABLE when open with an area of 2.07 square l !

inches.

Each of these methods of overpressure prevention is capable of mitigating the limiting OPPS transient.

APPLICABILITY This LCO is applicable in MODE 4 when any RCS cold leg temperature is less than or equal to the enable temperature, in MODE 5, and in MODE 6 when the reactor vessel head is on. When the reactor vessel ;

head is off, overpressurization cannot occur. ,

Low temperature overpressure prevention is most critical during .

shutdown when the RCS is water solid, and a mass or heat input transient can cause a very rapid increase in RCS pressure when little or no time allows operator action to mitigate the event. ;

i ACTION I a. With two or more charging pumps capable of injecting into i the RCS, RCS overpressurization is possible. !

To immediately initiate action to restore restricted ;

l coolant input capability to the RCS reflects the urgency l of removing the RCS from this condition.

l b. An unisolated accumulator requires isolation within 1 l hour. This is only required when the accumulator pressure

! is at or more than the maximum - RCS pressure for the l existing' temperature allowed by the P/T limit curves.

If isolation is needed and cannot be accomplished in 1 hour1.157407e-5 days 2.777778e-4 hours 1.653439e-6 weeks 3.805e-7 months , the ACTION provides two options, either of which i must be performed in the next 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months . By increasing the i' RCS temperature to more than the enable temperature, the accumulator pressure cannot exceed the OPPS limits if the j accumulators are fully injected. Depressurizing the l accumulators below the OPPS limit also gives this J. protection.

l The completion times are based on operating experience 3 that these activities can be accomplished in these time j periods indicating that an event requiring OPPS is not l likely in the allowed times.

i BEAVER VALLEY - UNIT 1 B 3/4 4-10g Amendment No.

j- (Proposed Wording) 4

.DPR-66 REACTOR COOLANT SYSTEM BASES (Continued) 3/4.4.9 PRESSURE / TEMPERATURE LIMITS (Continued)

ACTION (Continued)

c. In MODE 4 when any RCS cold leg temperature is less than or equal to the enable temperature, with one required RCS relief valve inoperable, the RCS relief valve must be restored to OPERABLE status within a completion time of 7 days. Two RCS relief valves are required to provide low temperature overpressure mitigation while withstanding a single failure of an active component.

The completion time considers the facts that only one of the RCS relief valves is required to mitigate an overpressure transient and that the likelihood of an active failure of the remaining valve path during this time period is very low. If plant operation results in transitioning to MODE 5, the completion time to restore an inoperable PORV may not exceed 7 days as required by this ACTION.

d. The consequences of operational events that will overpressurize the RCS are more severe at lower temperature. Thus, with one of the two RCS relief valves inoperable in MODE 5 or in MODE 6 with the head on, the completion time to restore two valves to OPERABLE status is 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months .

The completion time represents a reasonable time to investigate and repair several types of relief valve failures without exposure to a lengthy period with only I one OPERABLE RCS relief valve to protect against overpressure events. If a PORV is inoperable when the plant enters MODE 5 from MODE 4, the completion time to restore an inoperable PORV changes to 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months but the cumulative inoperable time may not exceed 7 days before taking action to depressurize and vent.

e. The RCS must be depressurized and a vent must be established within 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months when both required RCS relief valves are inoperable. The vent must be sized greater than or equal to 2.07 square inches to ensure that the flow l capacity is greater than that required for the worst case mass input transient reasonable during the applicable MODES. This action is needed to protect the RCPB from a t low temperature overpressure event and a possible brittle l failure of the reactor vessel.

1 l

BEAVER VALLEY - UNIT 1 B 3/4 4-10h Amendment No.

! (Proposed Wording)

I

!, .DPR-66

[ -

REACTOR COOLANT SYSTEM l BASES (Continued) ,

! 3/4.4.9- PRESSURE / TEMPERATURE LIMITS (Continued) {

i SURVEIT.tANCE REQUIREMENTS (SR) (Continued) i i '

i The'SR is required to be performed prior to entering the condition .

i for the OPPS to be OPERABLE. This assures low temperature !

l overpressure protection is available when the RCS cold leg '

l temperature is less than or equal to the enable temperature.

l Performing the surveillance every 31 days on each required PORV [

permits verification and adjustment, if necessary, of its lift setpoint, and considers instrumentation reliability which has been i shown through operating experience to be acceptable. The CHANNEL

{ FUNCTIONAL TEST will verify the setpoint is within the allowed i

? maximum limits. PORV actuation could depressurize the RCS and is !

not required. ;

!. Performance of a CHANNEL CALIBRATION on each required PORV actuation

l channel is required every 18 months to adjust the whole channel so

, that it responds and the valve opens within the required range and i accuracy to known input. i i !

I

! SR 4.4.9.3.3 i .

< The RCS vent of greater than or equal to 2.07 square inches is l i proven OPERABLE by verifying its open condition either: i 4

j a. Once every 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months for an open vent or valve that cannot !'

be locked, except

b. Once every 31 days for a valve that is locked, or provided with remote position indication, or sealed, or secured in ,

position. A removed pressurizer safety valve fits this category.

The passive vent arrangement must only be open to be OPERABLE. This surveillance is required to be performed if the vent is being used to satisfy the pressure relief requirements of the LCO. ;

i BEAVER VALLEY - UNIT 1 B 3/4 4-10j Amendment No.

(Proposed Wording) ,

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ML20086H002

Text

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