Text

Proposed Tech Specs,Clarifying TS to Allow Switching of Charging & low-head SI Pumps During Unit Shutdown Conditions
	ML20087A131
Person / Time
Site:	North Anna
Issue date:	07/26/1995
From:	; VIRGINIA POWER (VIRGINIA ELECTRIC & POWER CO.)
To:	;
Shared Package
ML20087A128	List: ML20087A125; ML20087A131;
References
	NUDOCS 9508040191
	Download: ML20087A131 (25)
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INDEX LIMITING CONDITIONS FOR OPERATION AND SURVEILLANCE REQUIREMENTS SECTION PAGE 3/4.4.2 SAFETY VALVES - SIIUTDOWN...

3/44-6 3/4.4.3 SAFETY AND RELIEF VALVES - OPERATING Safety Valves............

.... 3/4 4-7 Relief Valves....

.. 3/4 4-7a 3/4.4.4 PRESSURIZER.........

. 3/4 4-8 3/4.4.5 STEAM GENERATORS.....

3/44-9 3/4.4.6 REACTOR COOLANT SYSTEM LEAKAGE Leakage Detection Systems.

3/4 4-16 Operational Leakage.

3/4 4-17 Primary to Secondary Leakage..

. 3/4 4-18b Primary to Secondary Leakage Detection Systems..

... 3/4 4-18d 3/4.4.7 CllEMISTRY..

3/4 4-19 3/4.4.8 SPECIFIC ACTIVITY..

. 3/4 4-22 3/4.4.9 PRESSURE / TEMPERATURE LIMITS Reactor Coolant System..

3/4 4-26 Pressurizer..

. 3/4 4-30 Low-Temperature Overpressure Protection.

3/4 4-31 3/4.4.10 STRUCTURAL INTEGRITY ASME Code Class 1,2 & 3 Components..

. 3/4 4-33 3/4.4.11 REACTOR VESSEL llEAD VENT...

. 3/4 4-36 3/4.5 EMERGENCY CORE COOLING SYSTEMS (ECCS) 3/4.5.1 ACCUMULATORS.

3/4 5-1 j

3/4.5.2 ECCS SUBSYSTEMS -T GREATER TilAN OR EQUAL TO 350'F 3/4 5-3 avs 3/4.5.3 ECCS SUBSYSTEMS - T LESS THAN 350'F.

. 3/4 5-6 avy 9508040191 950726 PDR ADOCK 05000338 P

PDR l l NORTIl ANNA-UNIT I V

Amendment No. W32, 58,6 !.

IM.

BEACTIVITY CONTROL SYSTEMS CIIARGING PUMP-SILUTDOWN LIMITING CONDITION FOR OPERATION a !.2.3 One charging pump in the boron injection flow path required by Specification 3.1.2.1 l

shall be OPERABLE.

APPLICAl}lLITY:

MODES 5 and 6 ACTION; a.

With no charging pump OPERABLE, suspend all operations involving CORE j

ALTERATIONS or positive reactivity changes until one charging pump is restored to OPERABLE status.

b.

With no charging pump OPERABLE and the opposite unit in MODE 1,2,3 or 4, immediately init' ate corrective action to rettore at least one charging pump to OPERABLE status as soon as possible.

SURVEILLANCE REQUIREMENTS 4.1.2.3.1 The above required charging pu up shall be demonstrated OPERABLE by verifying, that on recirculation flow, the pump develops a discharge pressure of greater than or equal to 2410 psig when tested pursuant to Specification 4.0.5.

4.1.2.3.2 At least once per 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months , verify that a maximum of one charging pump is OPERABLE and capable of injecting into the RCS.*

i

[

Two charging pumps ray be OPERABLE and capable of injecting into the RCS during pump switching operations.

NORTil ANNA - UNIT I 3/4 1-11 Amendment No. W24, L

I REACTIVITY CONTROL SYSTEMS C11ARGING PUMPS - OPERATING LIMITING CONDITION FOR OPERATION 3.1.2.4 At least two charging pumps shall be OPFRABLE.

APPLICABILITY:

MODES 1,2,3 and 4 *.

ACTION:

With only one charging pump OPERABLE, restore a second charging pump to OPERABLE status within 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months or be in at least liOT STANDBY and borated to a S11UTDOWN MARGIN equivalent to at least 1.77% Ak/k at 200 F within the next 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months ; restore a second charging pump to OPERABLE status within the next 7 days or be in COLD SilUTDOWN within the next 30 hours3.472222e-4 days 0.00833 hours 4.960317e-5 weeks 1.1415e-5 months . The provisions of Specification 3.0.4 are not applicable for one hour following heatup above 235 F or prior to cooldown below 235 F.

SURVEILLANCE REQUIREMENTS 4.1.2.4.1 The above required charging pumps shall be demonstrated OPERABLE by verifying, that on recirculation flow, each pump develops a discha. e pressure of greater than or equal to l

2410 psig when tested pursuant to Specification 4.0.5.

4.1.2.4.2 At least once per 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months , verify that a maximum of one charging pump is OPERABLE and capable of injecting into the RCS whenever the temperature of one or more of the RCS cold legs is less than or equal to 235 F.**

A maximum of one charging pum:.; hall be OPERABLE end capable of injecting into the RCS whenever the temperature of one or more of the RCS cold legs is less than or equal to 235 F.

- Two charging pumps may be OPERABLE and capable ofinjecting into the RCS during pump switching operations.

- NORTil ANNA - UNIT l 3/4 1-12 Amendment No. A-46A4% Me 39, L

EMERGENCY CORE COOLING SYSTEMS ECCS SUBSYSTEMS - Tavg GREATER TIIAN OR EOUAL TO 350 F l

LIMITING CONDITION FOR OPERATION 3.5.2 Two independent ECCS subsystems shall be OPERABLE with each subsystem comprised of:

i a.

One OPERABLE charging pump, l

b.

One OPERABLE low head safety injection pump, c.

An OPERABLE flow path capable of transferring fluid to the Reactor Coolant System when taking suction from the refueling water storage tank on a safety injection signal or from the containment sump when suction is transferred during the recirculation phase of operation or from the discharge of the outside recirculation spray pump.

APPLICABILITY:

MODES 1,2 and 3.

ACTION _.;

With one ECCS subsystem inoperable, restore the inoperable subsy. tem to a.

OPERABLE status within 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months or be in IIOT SIIUTDOWN wit iin the next 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months .

b.

In the event the ECCS is actuated and injects water into die Reactor Coolant System, a Special Report shall be prepared and submitted to the Commission pursuant to Specification 6.9.2 within 90 days describing the circumstances cf the actuation and the total accumulated actuation cycles to date.

The provisions of Specification 3.0.4 are not applicable to 3.5.2.a and 3.5.2.b for c.

one hour following heatup above 235 F or prior to cooldown below 235 F.

L f

1 NORTil ANNA - UNIT I 3/4 5-3 Amendment No. 3d6A4h4%

170d89,

=m,

>N.w d

j l

l EMERGENCY CORE COOLING SYSTEM.

SNVEILLANCE REQUIREMENTS (Continued)

.r 2.

Verifying that each of the following pumps start automatically upon receipt l

of a safety injection test signal:

.{

a. Charging pump, and

~l

b. Low head safety injection pump.

D f.

By verifying that each of the following pumps develop the indicated discharge q

E pressure (after subtracting suction pressure) on recirculation flow when' tested pursuant to Specification 4.0.5.

j t.

1.

Charging pump greater than or equal to 2410 psig.

j 2.

Low head safety injection pump greater than or equal to 156 psig.

g.

By verifying that *be following manual valves requiring adjustment to prevent j

pump " runout" and subsequent component damage are locked and tagged in the

j proper position for injection

1.

Within 4 hours4.62963e-5 days 0.00111 hours 6.613757e-6 weeks 1.522e-6 months following completion of any repositioning or maintenance on the valve when the ECCS subsyctems are required to be OPERABLE.

1 2.

At least once per 18 months.

1.

1-SI-188 Loop A Cold Leg 2.

1-S1-191 Loop B Cold Leg 3.

1-S1-193 Loop C Cold Leg 4.

1-SI-203 Loop A Ilot Leg

5. 1-S1-204 Loop B llot Leg 6.

1-S1-205 Loop C llot Leg -

h.

By performing a Dow balance test, during shutdown, following completion of -

modifications to the ECCS subsystems that alter the subsystem 0ow characteristics and verifying that:

1 1.

For high head safety injection lines, with a single pump running:

a. The sum of the injection line flow rates, excluding the highest flow rate, is greater than or equal to the minimum flow rate required to demonstrate compliance with 10 CFR 50.46, and

b. The total pump flow rate is less than or equal to the evaluated pump runout limit.

i NORTil ANNA - UNIT I 3/45-5 Amendment No. 649,4WM6 488,-

7 1

J i.

EMENGENCY CORE COOLING SYSTEMS ECCS SUBSYSTEMS -Tavg LESS THAN 350 F l

LIMITING CONDITION FOR OPERATION 3.5.3 As a minimum, one ECCS subsystem comprised of the following shall be OPERABLE:

One OPERABLE charging pump #

l a.

b.

One OPERABLE low head safety injection pump", and c.

An OPERABLE flow path capable of automatically transferring Huid to the reactor coolant system when taking suction from the refueling water storage tank or from the containment sump when the suction is transfened during the recirculation phase of operation or from the discharge of the outside recirculation spray pump.

APPLICABILITY, MODE 4.

ACTION:

i With no ECCS subsystem OPERABLE because of the inoperability of either the a.

charging pump or the flow path from the refueling water storage tank, restore at l

least one ECCS subsystem to OPERABLE status within I hour or be in COLD SilUTDOWN within the next 20 hours2.314815e-4 days 0.00556 hours 3.306878e-5 weeks 7.61e-6 months .

b.

With no ECCS subsystem OPERABLE because of the inoperability of the low head safety injection pump, restore at least one ECCS subsystem to OPERABLE status or maintain the Reactor Coolant System T less than 350 F by use of alternate ag heat removal methods.

c.

In the event the ECCS is actuated and injects water into the Reactor Coolant System, a Special Report shall be prepared and submitted to the Commission pursuant to Specification 6.9.2 within 90 days describing the circumstances of the actuation and the total accumulated actuation cycles to date.

A maximum of one charging pump and one low head safety injection pump shall be OPERABLii and capable ofinjecting into the RCS whenever the temperature of one or more of the RCS cold legs is less than or equal to 235 F except two charging pumps may be OPERABLE and capable of injecting into the RCS during pump switching operations.

NORTil ANNA - UNIT I 3/4 5-6 Amendment No. M6744W4%

MOAK9,

1 EMERGENCY CORE COOLING SYSTEMS SURVEILLANCE REQUIREMENTS 4.5.3.1 The ECCS subsystem shall be demonstrated OPERA 13LE per the applicable Surveillance Requirernents of 4.5.2.

4.5.3.2 At least once per 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months , verify that a maximum of one charging pump and one low head safety injection pump is OPERABLE and capable of injecting into the RCS whenever the temperature of one or more of the RCS cold legs is less than or equal to 235 F.*

Tw o charging pumps may be OPER ABLE and capable ofinjecting into the RCS during pump switching operations.

NORTil ANNA - UNIT I 3/4 5-6a Amendment No. 46. l !?,174 439

\\_

e0 4

REACTIVITY CONTROL SYSTEMS BASES 3/4.1.2 BOR ATION SYSTEMS (Continued)

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 period.

The boration capability of either system is sufficient to provide a S11UTDOWN MARGIN from expected operating conditions of 1.77'/c Ak/k after xenon decay and cooldown to 20(FF. This expected boration capability requirement occurs at EOL from full power equilibrium xenon conditions and requires 6,000 gallons of 12,950 ppm borated water from the boric acid storage tanks or 54,200 gallons of 2300 ppm borated water from the refueling water storage tank.

The limitation for a maximum of one charging pump to be OPERABLE and the l

Surveillance Requirement to verify all charging pumps except the required OPERABLE pump to be inoperable below 235 F provides assurance that a mass addition pressure transient can be relieved by the operation of a single PORV.

Ilaving more than one charging pump OPERABLE during pump switching operations is allowed. This is acceptable based on pump switching being a momentary a<: tion under the direct administrative control of a licensed operator. Rendering a charging pump inoperable for this requirement may be accomplished by methods such as placing the control switch in the pull-to-lock position, tagging of the power supply breaker, or closing of the pump discharge valve (s).

With the RCS temperature below 20(FF, one injection system is acceptable without single failure consideration on the basis of the stable reactivity condition of the reactor and the additional restrictions prohibiting CORE ALTERATION and positive reactivity change in the event the single injection system becomes inoperable.

The boron capabihty required below 20(FF is sufficient to provide a SHUTDOWN M ARGIN of 1.77% AL/k after zenon decay and cooldown from 20(FF to 140'F. This condition requires either 1378 gallons of 12,950 ppm borated water from the boric acid storage tanks or 3400 gallons of 2300 ppm borated water from the refueling water storage tank.

The contained water volume limits include allowance for water not available because of l

discharge line location and other physical characteristics. The OPERABILITY of one boron injection system during REFUELING insures that this system is available for reactivity control w hile in MODE 6.

k NORTil ANNA - UNIT I B 3/41-3 Amendment No. 5,-ME, n2, 47 +M489, t

Eh1ERGENCY CORE COOLING SYSTEMS (ECCS)

BASES ECCS SUBSYSTEMS (Continp_td)

With the RCS temperature below 350 F, one OPERABLE ECCS subsystem is acceptable without single failure consideration on the basis of the sti.ble reactivity condition of the reactor and the limited core cooling requirements.

The limitation for a maximum of one charging pump and one low head safety injection pump to be OPERABLE and the Surveillance Requirement to verify that a maximum of one charging pump and one low head safety injection pump is capable of injecting into Ge RCS below 235 F provides assurance that a mass addition pressure transient can be relieved by the operation of a single PORV.

Ilaving more than one charging pump OPERABLE during pump switching operations is allowed. This is acceptable based on pump switching being a momentary action under the direct administrative control of a licensed operator. Rendering a charging pump inoperable for this requirement may be accomplished by methods such as placing the control switch in the pull-to-h>ck position, tagging of the power supply breaker, or closing of the pump discharge valve (s).

The Surveillance Requirements provided to ensure OPERABILITY of each component ensures that at a minimum, the assumptions used in the safety analyses are met and that subsystem OPERABILITY is maintained.

In the event of modifications to an ECCS subsystem that could alter the subsystem flow characteristics, a flow balance test shall be performed. The flow balance test criteria are established based on the system performance assumed in the safety analysis (minimum now limit) and on lillSi pump runout protection (maximum flow limit). In performing the flow balance, the effects of flow measurement instrument uncertainties accounting for system configuration and the i

variability between installed pumps must be properly considered.

Numerical acceptance criteria for the flow balance test are specified in surveillance kst procedure. These criteria are established based on the following considerations:

I) The total injected flow to the core (assuming spillage of the branch line with the highest How) must meet or exceed that assumed in the safety analysis. The limiting safety analysis is the loss of coolant accident (LOCA) analysis. This criterion may vary, particularly since the inputs to the safety analysis controlled by LCO 6.9.1.7 may vary with reload cycle. The safety analysis How requirements are thus established by the currently applicable LOCA analysis which has demonstrated compliance with the l

ECCS acceptance limits of 10 CFR 50.46.

2) The total pumped flow must be less than the lillSI pump runout limit. This flow varies with the specific 1111S1 pump assumed to operate during the accident. Since the 1111S1 pumps also function as normal charging pumps, their characteristics, including runout f

limits, will vary over service life.

l NORTli ANNA - UNIT 1 B 3/4 5-2 Amendment No. M.4,417,170, l

4%W.

L..

EMEldGENCY CORE COOLING SYSTEMS BASES

\\

ECCS SURSYSTEMS (Continued)

3) The requirements for reactor coolant pump seal injection must be met during normal operation, and the effects of seal injection during accidents must be considered in meeting constraints 1) and 2) above.

3/4.5.4 DORON INJECTION SYSTEM The OPERABILITY of the boron injection system as part of the ECCS ensures that sufficient negative reactivity is injected into the core to counteract any positive increase in reactivity caused by RCS system cooldown. RCS cooldown can be caused by inadvertent depressurization, a loss-of-coolant accident or a steam line rupture.

The limits on injection tank minimum contained volume and boron concentration ensure that the assumptions used in the steam line break analysis are met.

The OPERABILITY of the redundant heat tracing channels associated with the boron injection system ensure that the solubility of the boron solution will be maintained above the solubility limit of i11 F at 15,750 ppm boron.

3/4.5.5 REFUELING WATER STORAGE TANK The OPERABILITY of the RWST as part of the ECCS ensures that a sufficient supply of borated water is available for injection by the ECCS in the event of a LOCA. The limits on RWST minimum volume and boron concentration ensure that 1) sufficient water is available within containment to permit recirculation cooling flow to the core, and 2) the reactor will remain suberitical in the cold condition following mixing of the RWST and the RCS water volumes with all control rods inserted except for 'he most reactive control assembly. These assumptions are consistent with the LOCA analyses.

The contained water volume limit includes an allowance for water not usable because of tank discharge line location or other physical characteristics.

The limits on contained water volume and boron concentration of the RWST also ensure a pli value of between 8.5 and 11.0 for quench spray and between 7.7 and 9.0 for the solution recirculated within the containment after a LOCA. This pli minimizes the evolution ofiodine and minimizes the effect of chloride and caustic stress corrosion on mechanical systems and components.

An RWST wide range level instrument loop uncertainty was included in the safety analysis and therefore need not be considered by the operator.

NORTil ANNA - UNIT I B 3/4 5-3 Amendment No. 46,93, ! 10,188,

T-L ;.,

INDEX i

LIMITING bONDITIONS FOR OPERATION AND SURVEILLANCE REQUIREM SECTION FAGE 3/4.4.2 S AFETY VALVES - S liUTDOWN.................................................... 3/4 426 3/4.4.3 SAFETY AND RELIEF VALVES - OPERATING Safety Valves....

............................................................3/44-7 l

l Relie f Valves...........................

................. 3/4 4-7a l

t 3/4.4.4 PR ES S U RIZE R........................................................ 3/4 4-8 I

3/4.4.5 STEAM GEN ERATORS..............................

......... 3/4 4-9 i

3/4.4.6 REACTOR COOLANT SYSTEM LEAKAGE i

Leakage Detection Systems..........................

............... 3/4 4-16 f

Operational Leakage....

................. 3/4 4-17 Primary to Secondary Leakage.........

....................... 3/4 4-18 b Primary to Secondary Leakage Detection Systems.......

.. 3/4 4-18d 3/4.4.7 ClIEMISTRY........

......................................................3/44-19 f

3/4.4.8 SPECIFIC ACTIVITY.................................................... 3 /4 4 - 2 2 3/4.4.9 PRESSURE / TEMPERATURE LIMITS Reactor Coolant S yst e m................................................... 3/4 4-26 Pre s s u rize r................................................................... 3/4 4-29 l

r Low-Temperature Overpressure Protection..................

.... 3/4 4-30 l

i 3/4.4.10 STRUCTURALINTEGRITY ASME Code Class 1, 2 & 3 Components....................

... 3/4 4-32 3/4.4.11 REACTOR VESSEL ilEAD VENT............

....... 3/4 4-34 i

i 3/4.5 liMERGENCY CORE COOLING SYSTEMS (ECCS) 3/4.5.1 ACCUMULATORS..

...... 3/4 5-1 3/4.5.2 ECCS SUBSYSTEMS -Tavg GREATER TilAN OR EQUAL TO 350 F 3/4 5-3 l

)

3/4.5.3 ECCS SUBSYSTEMS -Tavg LESS TIIAN 350*F.............

. 3/4 5 6

)

3/4.5.4 BORON INJECTION SYSTEM Boron Injection Tank.....,....

3/4 5.

L

{

lleat Tracing......

.......... 3/4 5-9.

3/4.5.5

- REFUELING WATER STORAGE TANK,

3/4 5...........

NORTil ANNA - UNIT 2 V

Amendment No. 44,19,170, i

l

/

,a i

REACTIVITY CONTROL SYSTEMS

.i

- CIIARGING PUMP-SHUTDOWN LIMITIN

'ONDITION FOR OPERATION 3.1.2.3 One charging pump in the boron injection flow path required by Specification 3.1.2.1 l

l shall be OPERABLE.

P APPLICABILITY:

MODES 5 and 6.

ACTION:

I 1

With no charging pump OPERABLE, suspend all operations involving CORE a.

ALTERATIONS or positive reactivity changes until one charging pump is restored

)

to OPERABLE status.

I b.

With no charging pump OPERABLE and the opposite unit in MODE 1,2,3 or 4 immediately initiate corrective action to restore at least one charging pump to OPERABLE status as soon as possible.

I SURVEILLANCE REQUIREMENTS 4.1.2.3.1 The above required charging pump shall be demonstrated OPERABLE by verifying, that on recirculation flow, the pump develops a discharge pressure of greater than or equal to 2410 psig when tested pursuant to Specification 4.0.5.

4.1.2.3.2 At least once per 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months , verify that a maximum of one charging pun.p is OPERABLE and capable of injecting into the RCS.*

l l

I l

Two charging pumps may be OPER ABLE and capable of injecting into the RCS during pump switching operations.

1 NORTil ANNA - UNIT 2 3/4 1-11 Amendment No. 5, l

[

3 g

EEAdrIVITY CONTROL SYSTEMS CJIARGING PUMPS - OPERATING LIMITING CONDITION FOR OPERATION 3.1.2.4 ~ ' At least two charging pumps shall be OPERABLE.

APPLICABJLITY:

MODES 1,2,3 and 4.

ACTION:

With only one charging pump OPERABLE, restore a second charging pump to OPERABLE status -

within 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months or be in at least HOT STANDBY and borated to a SliUTDOWN MARGIN equivalent to at least 1.77% della k/k at 200 F within the next 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months ; restore a second charging pump to OPERABLE status within the next 7 days or be in COLD SHUTDOWN within the next-30 hours. The provisions of Specification 3.0.4 are not applicable for one hour following heatup above 270 F or prior to cooldown below 270 F.

SURVEILLANCE REQUIREMENTS 4.1.2.4.1-The above required charging pumps shall be demonstrated OPERABLE by verifying, that on recirculation flow, each pump develops a discharge pressure of greater than or equal to 2410 psig when tested pursuant to Specification 4.0.5.

4.1.2.4.2 At least once per 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months , verify that a maximum of one charging pump is OPERABLE and capable of injecting into the RCS whenever the temperature of one or more of.

the RCS cold legs is less than or equal to 270 F.##

A maximum of one charging pump shall be OPERABLE and capable of injecting into the RCS w henes er the temperature of one or more of the RCS cold legs is less than or equal to 270'F.

1. - Two LSarging pumps may be OPERABLE and capable of injecting into the RCS during pump switching operations.

NORTil ANNA - UNIT 2 3/4 1-12 Amendment No. 44%474).

4 3,c o.

a j

EMERGENCY CORE COOLING SYSTEMS i

ECCS SUBSYSTEMS -Tavg GREATER THAN OR EOUAL TO 350 F

-l

}

LIMITING CONDITION FOR OPERATION i

3.5.2 Two independent ECCS subsystems shall be OPERABLE with each subsystem comprised of:

One OPERABLE charging pump, l

a.

b.

One OPERABLE low head safety injection pump, c.

An OPERABLE flow path capable of transferring fluid to the Reactor Coolant j

System when taking suction from the refueling water storage tank on a safety injection signal or from the containment sump when suction is transferred during the recirculation phase of operation.

APPLICABILITY:

MODES 1,2 and 3.

ACTION:

l a.

With one ECCS subsystem inoperable, restore the inoperable subsystem to OPERABLE status within 72 hours8.333333e-4 days 0.02 hours 1.190476e-4 weeks 2.7396e-5 months or be in HOT SilUTDOWN within the next 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months .

b.

In the event the ECCS is actuated and injects water into the Reactor Coolant System, a Special Report shall be prepared and submitted to the Commission pursuant to Specification 6.9.2 within 90 days describing the circumstances of the l

actuation and the total accumulated actuation cycles to date. The current value of l

the usage factor for each affected safety injection nozzle shall be provided in this Special Report whenever its value exceeds 0.70.

c.

The provisions of Specification 3.0.4 are not applicable to 3.5.2.a and 3.5.2.b for i

one hour following heatup above 270 F or prior to cooldown below 270 F.

SURVEILLANCE REQUIREMENTS 1

4.5.2 Each ECCS subsystem shall be demonstrated OPERABLE:

At least once per 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months by verifying that the following valves a:e in the indicated a.

positions with power to the valve operators removed:

NORTil ANNA - UNIT 2 3/453 Amendment No.14M70, j

i

w h.g.

(:

EMERGENCY CORE COOLING' SYSTEMS l

i SURVEILLANCE REQUIREMENTS (Continued) i i

Valve Number Valve Function Valve Position a.

MOV-2890A.

a. LilSI to hot leg

a. closed.

b. MOV-2890B

b. LHSI to hot leg

b. closed t

c. MOV-2836

c. Ch pump to cold leg

c. closed

d. MOV-2869A~

d. Ch pump to hot leg

d. closed c.

MOV-2869B e.

Ch pump to hot leg

e. closed b.

At least once per 31 days by verifying that each valve (manual, power operated or automatic) in the flow path that is not locked, sealed, or otherwise secured in position, is in its correct position.

c.

By a visual inspection which verifies that no loose debris (rags, trash, clothing, etc.)

is present in the containment which could be transported to the containment sump and cause restriction of the pump suctions during LOCA conditions, This visual inspection shall be performed:

1.

For all accessible areas of the containment prior to estt.blishing CONTAINMENT INTEGRITY, and j

2.

Of the areas affected within containment at the completion of each containment entry when CONTAINMENT INTEGRITY is' established.

{

r d.

At least once per 18 months by:

1.

A visual inspection of the containment sump and verifying that the subsystem suction inlets are not restricted by debris and that the sump components (trash racks, screens, etc.) show no evidence of structural -

distress or corrosion.

At least once per 18 months, during shutdown, by:

c.

1.

Verifying that each automatic valve in the flow path actuates to its correct position on a safety injection test signal.

I i

2.

Verifying that each of the following pumps start automatically upon receipt i

of a safety injection test signal:

a) Charging pump, and l

b) isw head safety injection pump.

NORTH ANNA - UNIT 2 3/4 5-4

. Amendment No.

i r

i s

EMERGENCY CORE COOLING SYSTEM SURVEILLANCE REQUIREMENTS (Continued) f.

By verifying that each of the following pumps develop the indicated discharge pressure (after subtracting suction pressure) on recirculation flow when tested pursuant to Specification 4.0.5.

1.

Charging pump greater than or equal to 2410 psig.

l l

2.

Low head safety injection pump greater than or equal to 156 psig.

g.

By verifying that the following manual valves requiring adjustment to prevent pump " runout" and subsequent component damage are locked and tagged in the proper position for injection:

1.

Within 4 hours4.62963e-5 days 0.00111 hours 6.613757e-6 weeks 1.522e-6 months following completion of any repositioning or maintenance on the valve when the ECCS subsystems are required to be OPERABLE.

2.

At least once per 18 months.

1. 2-SI-89 Loop A Cold Leg

2. 2-SI-97 Loop B Cold Leg

3. 2-SI-103 Loop C Cold Leg

4. 2-SI-l 16 Loop A Ilot Leg

5. 2-SI-111 Loop B llot Leg 6.

2-SI-123 Loop C llot Leg h.

By performing a flow balance test, during shutdown, following completion of modifications to the ECCS subsystems that alter the subsystem flow characteristics and verifying that:

1.

For high head safety injection lines, with a single pump mnning:

a) The sum of the injection line flow rates, excluding the highest flow rate, is greater than or equal to the minimum flow rate required to demonstrate compliance with 10 CFR 50.46, and b) The total pump flow rate is less than or equal to the evaluated pump runout limit.

NORTil ANNA - UNIT 2 3/4 5-5 Amendment No. 451d47d69,

., J

- EMERGENCY CORE COOLINO SYSTENIS ECCS SUBSYSTEMS -Tavg LESS THAN 350 F LIMITING CONDITION FOR OPERATION 3.5.3 As a minimum, one ECCS subsystem comprised of the following shall be OPERABLE:

One OPERABLE charging pump",

l a.

b.

One OPERABLE low head safety injection pump", and An OPERABLE Dow path capable of automatically transferring Duid to the reactor c

coolant system when taking suction from the refueling water storage tank or from the containment sump when the suction is transferred during the recirculation phase of operation.

APPL.lCABILITY:

MODE 4.

ACTION:

With no ECCS subsystem OPERABLE because of the inoperability of either the a.

charging pump or the flow path from the refueling water s'.orage tank, restore at l

least one ECCS subsystem to OPERABLE status within I hour or be in COLD SHUTDOWN within the next 20 hours2.314815e-4 days 0.00556 hours 3.306878e-5 weeks 7.61e-6 months .

b.

With no ECCS subsystem OPERABLE because of the inoperability of the low head safety injection pump, restore at least one ECCS subsystem to OPERABLE status or maintain the Reactor Coolant System T less than 350 F by use of alternate ag heat removal methods.

)

c.

In the event the ECCS is actuated and injects water into the Reactor Coolant System, a Special Report shall be prepared and submitted to the Commission pursuant to Specification 6.9.2 within 90 days describing the circumstances of the actuation and the total accumulated actuation cycles to date. The current value of the usage factor for each affected safety injection nozzle shall be provided in this Special Report whenever its value exceeds 0.70.

A maximum of one charging pump and one low head safety injection pump shall be OPERABLE and capable of injecting into the RCS whenever the temperature of one or more of the RCS cold legs is less than or equal to 270 F except two charging pumps may be OPERABLE and capable of injecting into the RCS during pump switching operations.

NORTil ANNA - UNIT 2 3/4 5-6 Amendment No. ?!, ! 19.170,

r EMEEQFJiCY COREf00 LING SYSTEMS SURVEILLANCE REQUIREMENTS 4.5.3.1 The ECCS subsystem shall be demonstrated OPERABLE per the applicable Surveillance Requirements of 4.5.2.

4.5.3.2 At least once per 12 hours1.388889e-4 days 0.00333 hours 1.984127e-5 weeks 4.566e-6 months , verify that a maximum of one charging pump and one low head safety injection pump is OPERABLE and capable of injecting into the RCS whenever the temperature of one or more of the RCS cold legs is less than or equal to 270'F.*

Two charging pumps may be OPERABLE and capable ofinjecting into the RCS during pump switching operations.

NORTil ANNA - UNIT 2 3/4 5-7 Amendment No. 444170,

REACTIVITY CONTROL SYSTEMS BASES l

3/4.1.2 BOR ATION SYSTEMS The boron injection system ensures that negative reactivity control 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 supply from OPERABLE diesel generators.

With the RCS average temperature above 200 F, a minimum of two boron injection flow paths are required to ensure single functional capability in the event an assumed failure renders one j

of the flow paths inoperable. The boration capability of either flow path is sufficient to provide a

)

SilUTDOWN M ARGIN from expected operation conditions of 1.77% delta k/k after xenon decay and cooldown to 200 F. The maximum expected boration capability requirement occurs at EOL from full power equilibrium xenon conditions and requires 6000 gallons of 12,950 ppm borated

)

water from the boric acid storage tanks or 54,200 gallons of 2300 ppm borated water from the refueling water storage tank.

l With the RCS temperature below 200 F, one injection system is acceptable without single failure consideration on the basis of the stable reactivity condition of the reactor and the additional restrictions prohibiting CORE ALTERATIONS and positive reactivity change in the event the single injection system becomes inoperable.

The limitation for a maximum of one charging pump to be OPERABLE and the l

Surveillance Requirement to verify all charging pumps except the required OPERABLE pump to be inoperable below 270'F provides assurance that a mass addition pressure transient can be relieved by the operation of a single PORV.

Ilaving more than one charging pump OPERABLE during pump switching operations is allowed. This is acceptable based on pump switching being a momentary action under the direct administrative control of a licensed operator. Rendering a charging pump inoperable for this requirement may be accomplished by methods such as placing the control switch in the pull-to-lock position, tagging of the power supply breaker, or closing of the pump discharge valve (s).

The boron capability required below 200 F is sufficient to provide a SHUTDOWN M ARGIN of 1.779 delta k/k after zenon decay and cooldown from 200 F to 140 F.This condition requires either 1378 gallons of 12,950 ppm borated water from the boric acid storage tanks or 3400 gallons of 2300 ppm borated water from the refueling water storage tank.

NORTil ANNA - UNIT 2 B 3/4 1-3 Amendment No. M. 78,!19,470,

..; i.

EMERGENCY CORE COOLING SYSTEMS (ECCS)

BASES ECCS SUBSYSTEMS (Continuedj With the RCS temperature below 350 F. one OPERABLE ECCS subs). tem is acceptable without single failure consideration on the basis of the stable reactivity condition of the reactor and the limited core cooling requirements.

The limitation for a maximum of one charging pump and one low head safety injection pump to be OPERABLE and the Surveillance Requirement to verify that a maximum of one charging pump and one low head safety injection pump is capable of injecting into the RCS below 270*F provides assurance that a mass addition pressure transient can be relieved by the operation of a single PORV.

Having more than one charging pump OPERABLE during pump switching operations is allowed. This is acceptable based on pump switching being a momentary action under the direct administrative control of a licensed operator Rendering a charging pump inoperable for this requirement may be accomplished by methods such as placing the control switch in the pull-to-lock position, tagging of the power supply breaker, or closing of the pump discharge valve (s).

The Surveillance Requirements provided to ensure OPERABILITY of each component ensures that at a minimum, the assumptions used in the safety analyses are met and that subsystem j

OPERAlllLITY is maintained.

In the event of modification to an ECCS subsystem that could alter the subsystem flow i

characteristics, a flow balance test shall be performed. The flow balance test criteria are established based on the system performance assumed in the safety analysis (minimum flow limit) and on lillSI pump runout protection (maximum flow limit). In performing the flow balance, the effects of How measurement instrument uncertainties accounting for system configuration and the variability between installed pumps must be properly considered.

Numerical acceptance criteria for the flow balance test are specified in the surveillance test procedure. These criteria are established based on the following considerations:

1) The total injected flow to the core (assuming spillage of the branch line with the highest flowl must meet or exceed that assumed in the safety analysis. The limiting safety analysis is the loss of coolant accident (LOCA) analysis. This criterion may vary, particularly since the inputs to the safety analysis controlled by LCO 6.9.1.7 may vary with reload cycle. The safety analysis flow requirements are thus established by the currently applicable LOCA analysis which has demonstrated compliance with the ECCS acceptance limits of 10 CFR 50.46.

2) The total pumped flow must be less than the 1111S1 pump runout limit. This How varies with the specific lillSI pump assumed to operate during the accident. Since the HilSI pumps also function as normal charging pumps, their characteristics, including runout limits, will vary over service life.

NORTil ANNA - UNIT 2 113/45-2 Amendment No. 54449AM MG,

rJ,;

Eh1ERGENCY CORE COOLING SYSTEMS BASES

.=

ECCS SUBSYSTEMS (Continuedi

3) The requirements for reactor coolant pump seal injection must be met during normal operation, and the effects of seal injection during accidents must be considered in meeting constraics 1) and 2) above.

3/4.5.4 EORON INJECTION SYSTEM The OPERABILITY of the boron injection system as part of the ECCS ensures that sufficient negative reactivity is injected into the core to counteract any positive increase in reactivity caused by RCS system cooldown. RCS cooldown can be caused by inadvertent depressurization, a loss-of-coolant accident or a steam line rupture.

The limits on injection tank minimum contained volume and boron concentration ensure that the assumptions used in the steam line break analysis are met. The contained water volume limit includes an allowance for water not usable because of tank discharge line location or other physical characteristics.

The OPERABILITY of the redundant heat tracing channels associated with the boron injection system ensure that the solubility of the baron solution will be maintained above the solubility limit of i1i F at 15,750 ppm boron.

3/4.5.5 REFUELING WATER STORAGE TANK The OPERABILITY of the RWST as part of the ECCS ensures that a sufficient supply of borated water is available for injection by the ECCS in the event of a LOCA. The limits on RWST minimum volume and boron concentration ensure that 1) sufficient water is available within containment to permit recirculation cooling flow to the core, and 2) the reactor will remain suberitical in the cold condition following mixing of the RWST and the RCS water volumes with all control rods inserted except for the most reactive control assembly. These assumptions are consistent with the LOCA analyses.

The contained water volume limit includes an allowance for water not usable because of tank discharge line location or other physical characteristics.

The limits on contained water volume and boron concentration of the RWST also ensure a pil value of between 8.5 and i 1.0 for quench spray and between 7.7 and 9.0 for the solution recirculated within the containment after a LOCA. This pH minimizes the evolution of iodine and minimires the effect of chloride and caustic stress corrosion on mechanical systems and components.

F l

An RWST wide range level instrument loop uncertainty was included in the safety analysis and therefore need not be considered by the operator.

i NORTil ANNA - UNIT 2 B 3/4 5-3 Amendment No. 78, W, M9,

.J

ej /*

g.

ATTACHMENT 3 r

SIGNIFICANT HAZARDS CONSIDERATION l

l

\\

VIRGINIA ELECTRIC AND POWER COMPANY I

Significant Hazards Consideration Each unit at the North Anna Power Station is equipped with three charging pumps.

These charging pumps provide inventory control, normal boration to the reactor coolant system (RCS), and flow to the reactor coolant pump seals. They also act as the high head safety injection pumps during accident conditions. During certain shutdown conditions, it is necessary to render two of the three charging pumps inoperable to maintain the low-temperature overpressure protection (LTOP) design bases assumptions. This provides assurance that a mass addition pressure transient can be relieved by the operation of a single pressurizer power-operated relief valve (PORV). Low-temperature overpressure protection for each unit at the North Anna Power Station is provided by two pressurizer PORVs.

During shutdown conditions, periodic surveillance testing of the charging pumps is required by Technical Specifications. Also during shutdown conditions, it may be desirable to switch from one charging pump to another to allow for other activities such as maintenance or testing. The current Technical Specifications associated with charging pumps during shutdown conditions are very restrictive and do not allow sufficient latitude for surveillance testing or pump switching.

Specifically, with the RCS temperature less than 235 F (270 F for Unit 2) in Mode 4,5, and 6 (when the head is on the reactor vessel), the Technical Specifications could be interpreted to require that one, and only one, charging pump or shall be operable and capable of injecting into the RCS. Although these Technical Specifications restrictions are intended to address a low-temperature overpressure protection (LTOP) concern, these requirements could be interpreted to preclude the starting of a second pump to facilitate swapping charging pumps during these modes of operation. Isolation of the in service charging pump from the RCS prior to establishing a flow path from another charging pump is undesirable because it would result in a momentary loss of seal injection to the reactor coolant pumps and isolate the RCS makeup source. The momentary loss of seal injection to a running reactor ' coolant pump would unnecessarily increase the probability of reactor coolant pump seal damage.

The current Technical Specifications specifically state in the surveillance requirements that the method used to render a charging pump inoperable is to place the pump control switch in the pull-to-lock position. This requirement would not allow for Page 1 of 3

o,.. t.

surveillance or post-maintenance testing of the inoperable charging pumps since this switch is used to start those pumps.

Therefore, Virginia Electric and Power Company proposes to modify the North Anna Units 1 and 2 Technical Specifications to allow more than one charging pump to be operable and capable of injecting into the RCS for pump switching operations.

Additionally, the methods used to render charging pumps inoperable will be expanded to allow for post-maintenance and surveillance testing.

Virginia Electric and Power Company has reviewed the proposed changes against the criteria of 10 CFR 50.92 and has concluded that the changes, as proposed, do not pose a significant hazards consideration. Specifically, operation of North Anna Power Station in accordance with the proposed Technical Specifications changes will not:

1. Involve a significant increase in the probability or consequences of an accident previously evaluated.

Allowing more than one charging pump to be operable and capable of injecting into the RCS during RCS low temperature operation for pump switching for post-maintenance and surveillance testing does not increase the probability of occurrence or the consequences of any previously analyzed accident. Pump switching operations will be under the direct administrative control of a licensed operator and will only be for a short duration of time. Any situation that could result in an excessive RCS mass addition would be immediately recognized by the operator and remedial action would be taken to prevent challenges to RCS integrity. Using methods such as opening the charging pump power supply breaker or closing the charging pump discharge valve (s) to render a charging pump inoperable will ensure that these pumps will not be capable of injecting water into the RCS. These alternate methods are as effective as placing the control switches in the pull-to-lock position.

2. Create the possibility of a new or different kind of accident from any accident previously evaluated.

[

Allowing more than one charging pump to be operable and capable of injecting into the RCS during low-temperature operation for pump switching for post-maintenance and surveillance testing does not involve any physical l

Page 2 of 3

g.7 modifications of the plant nor result in a change in a method of operation.

Licensed operator control of charging pump switching operations will continue to ensure that the RCS will not be challenged by excessive mass addition events. Using methods other than placing charging pump control switches in the pull-to-lock position to render the pump inoperable will still ensure that only one pump will be capable of injecting into the RCS during low temperature operations. Therefore, a new or different type of accident is not made possible.

3. Involve a significant reduction in a margin of safety.

Allowing more than one charging pump to be operable and capable of injecting into the RCS during RCS low temperature operation for pump switching for post-maintenance and surveillance testing does not affect any safety limits or limiting safety system settings. The alternate methods of rendering pumps inoperable provide the same level of assurance that the pump is incapable of flowing into the RCS as placing the pump control switch in the pull-to-lock position.- System operating parameters remain unaffected. The availability of i

equipment required to mitigate or assess the consequence of an accident is not reduced. Safety margins are, therefore, not decreased.

Based on the above evaluation, Virginia Electric and Power Company concludes that the proposed Technical Specification changes satisfy the no significant hazards consideration of the criteria of 10 CFR 50.92 and, accordingly, a no significant hazards consideration finding is justified.

t Page 3 of 3

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ML20087A131

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