Text

Proposed Tech Specs Re Increased Requirements for Core Reactivity Control Available from Borated Water Sources
	ML20085L116
Person / Time
Site:	Seabrook
Issue date:	06/16/1995
From:	; NORTH ATLANTIC ENERGY SERVICE CORP. (NAESCO)
To:	;
Shared Package
ML20085L113	List: ML20085L110; ML20085L116;
References
	NUDOCS 9506280307
	Download: ML20085L116 (17)
	v • d • e

-- . - _ _ _ _

l REACTIVITY CONTROL SYSTEMS BORATIOff SYSTEMS BORATED WATER SOURCES - SHUTDOWN LIMITING CONDITION FOR OPERATION 3.1.2.5 As a minimum, one of the following borated water sources shall be OPERABLE:

a. A Boric Acid Storage System with:

I

1) A minimum contained borated water volume of 6,500 gallons,

2) A minimum boron concentration of 7000 ppm, and .

3) A minimum solution temperature of 65*F. j

b. The refueling water storage tank (RWST) with:

1) A minimum contained borated water volume.of 24,500 gallons, {

2) A minimum boron concentration pm, and

3) A minimum solution temperature of 50 F.

APPLICABILITY: MODES 5 and 6.

ACTION:

With no borated water. source OPERABLE, suspend all operations involving CORE ALTERATIONS or positive reactivity changes. -

SURVEILLANCE REQUIREMENTS 4.1.2.5 The above required borated water source shall be demonstrated OPERABLE:

a. At least once per 7 days by: ,

1) Verifying the boron concentration of the water,

2) Verifying the contained borated water volume, and

3) Verifying the boric acid storag'e tank solution temperature when it is the source of borated water.

b. At least once per 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months by verifying the RWST temperature.

SEABROOK - UNIT 1 3/4 1-11 9506280307 950616 PDR ADOCK 05000443 P PDR

REACTIVITY CONTROL SYSTEMS 80 RATION SYSTEMS BORATED WATER SOURCES - OPERATING P

LIMITING CONDITION FOR OPERATION 1 3.1.2.6 As a minimum, the following borated water sources shall be OPERABLE as required by Specification 3.1.2.2: -

a. A Boric Acid Storage System with: ,

1) A minimum contained borated water volume of 22,000 gallons,

2) A minimum boron concentration of 7000 ppm, and

3) A minimum solution temperature of 65*F.

b. The refueling water storage tank (RWST) with:

1) A minimum contained borated water volume of 477,000 callons.__ '

tw een 2.700 qwd 2,960] ,

2) Al5i..iqj)boronconcentratio _f20qg) ppa, j

3) A minimum solution temperature of 50'F, and

4) A maximum solution temperature of 98'F.

APPLICABILITY: MODES 1, 2, 3, and 4.

ACTION:

a. With the Boric Acid Storage System inoperable and being used as one of the above required borated water sources, restore the system 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 within the next 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months and borated to a SHUTDOWN MARGIN equivalent to at least the limit specified in the CORE OPERATING LIMITS REPORTS (COLR) for the above MODES at 200*F; restore the Boric Acid Storage System to OPERABLE status within the next 7 days or be in COLD SHUTDOWN within the next 30 hours3.472222e-4 days 0.00833 hours 4.960317e-5 weeks 1.1415e-5 months .

b. With the RWST inoperable, restore the tank to OPERABLE status within 1 hour1.157407e-5 days 2.777778e-4 hours 1.653439e-6 weeks 3.805e-7 months or be in at least HOT STANDBY within the next 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months and in COLD SHUTDOWN within the 'following 30 houri.

i SEABROOK - UNIT 1 3/4 1-12 Amendment No. 9 j

c*., .

,3/4.5 ' EMERGENCY CORE COOLING SYSTEMS s j?e O ,l cTis, .[C@E,.E' -

m.

3/4.5.1 ACCUMULATORS

" ^

,jy. , 33 l

%, f..g q,;;g ' .

i HOT STANDBY. STARTUP. AND POWER OPERATION

~~

LIMITING CONDITION FOR OPERATION.

. ;a w w.,. !

3.5.1.1 Each Reactor Coolant System (RCS) accumulator shall be OPERABLE withi .'.. '

i

a. The isolation valve open and power removed,

b. A contained borated water volume o twee 6596 gallons,

. c. A boron concentration of betwee and g ppm, and .

d. Anitbgen. cover-pressureofbetween585and664psig. . i APPLICABILITY: MODES 1, 2, and 3*. , l ACTION: .

i

a. With one accumulator inoperable, except as a result of a closed ,

isolation valve, restore the inoperable accumulator to OPERABLE .

status within 8 hours9.259259e-5 days 0.00222 hours 1.322751e-5 weeks 3.044e-6 months or be in at least HOT STANDBY within the ;

next 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months and reduce pressurizer pressure to less than 1000 psig within the following 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months .

b. With one accumulator inoperable due to the isclation valve being closed, e.ither immediately open the . isolation valve or be in at

'least HOT STANDBY within 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months and reduce pressurizer pressure ,

to less than 1000 psig within the following 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months .

c. With one pressure or water level channel inoperable per i accumulator, return the inoperable channel to OPERABLE status --

within 30 days or be in at least HOT STANDBY within the next 6 !

hours and in HOT SHUTDOWN within the following 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months . l i

d. With two pressure channels or two water level channels, inoperable

. per accumulator, immediately declare the affected Accumulator (s) '

inoperable. !

~

SURVEILLANCE REOUIREMENTS -

l 4.5.1.1 Each accumulator shall be demonstrated OPERABLE:

a. At least once per 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months by:

, 1) Verifying the contained borated water volume and nitrogen I cover-pressure in the tanks, and

Pressurizer pressure above 1000 psig.

SEASR00K - UNIT 1 3/4 5-1 Amendment No. 30 l

BORON INJECTION SYSTEM 3/4.5.4 REFUELING WATER STORAGE TANK LIMITING CONDITION FOR OPERATION 3.5.4 The ~ refueling water storage tank (RWST) shall be OPERABLE with:

a. A minimum contained borated water volume of 477.000 gallons,

b. A @ r"uB boron' concentratigbetw on w. 2000lppm een of2.boron, lo o g h d 2.1603

c. A minimum solution temperature of 50 F, and e, d. A maximum solution temperature of 98 F.

n-APPLICABILITY: MODES 1, 2, 3, and 4.

ACTION:

With the RWST inoperable, restore the tank to OPERABLE status within 1 hour1.157407e-5 days 2.777778e-4 hours 1.653439e-6 weeks 3.805e-7 months or be in at least following 30 HOT STANDBY within 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months and in COLD SHUTDOWN within the hours.

SURVEILLANCE REQUIREMENTS 1

4.5.4 The RWST shall be demonstrated OPERABLE: ,

a. At least once per 7 days by:

1) Verifying the contained borated water volume in the tank, and

2) Verifying the boron concentration of the water.

b. At least once per 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months by verifying the RWST temperature.

. j SEABROOK - UNIT 1 3/4 5-11

{ ,

p. &

REACTIVfTY CONTROL SYSTEMS 3 BASES B0 RATION CONTROL 3/4.1.1.3 MODERATOR TEMPERATURE COEFFICIENT (Continued)

The surveillance requirements for measurement of the MTC at the beginning and near the end of the fuel cycle are adequate to confim that the MTC remains within its limits since this coefficient changes slowly due principally to the reduction in RCS boron concentration associated with fuel burnup.

loadingPrior to initial operation above 5% RATED THERMAL POWER after each fuel l

A measur,ement bias is derived from the difference between test measuremen

! test preciction. All predicted values of MTC for the cycle are conservatively corrected based on measurement bias. The corrected predictions are then ,

4 compared to the maximum upper limit of Technical Specification 3.1.1.3.

Control rod withdrawal limits are established if required, to assure all corrected values of predicted MTC will be less, positive Dan the maximum upper limit required by Technical Specification 3.1.1.3.

3/4.1.1.4 MINIMUM TEMPERATURE FOR CRITICALITY This specification ensures that the reactor will not be made critical with the Reactor Coolant System average temperature less than 551' F. This limitation is required to ensure: 1 within its analyzed temperature rang (e,) (2)the moderator the temperature is trip instrumentation coefficient within is its nomal operating range, (3 the OPERABLE status with a steam bu)bble, pressurizer is capable of being in an minimurn RT, temperature. and (4) the reactor vessel is above its 3/4.1.2 BORATION SYSTEMS The Boron Injection System ensures that negative reactivity control is available perform this during function each include:

mode of facility operation. The components required to 1 borated water sources (3) separate flow paths -(4) bora[c) acid transfer pumps, (5) an,d(2) charging pumps, an emergency powersupplyfromOPERAblEdieselgenerators.

With the RCS in MODES 1 2 or 3, a minimum of two boron injection flow paths are required to ensure s,in le functional capability in the event an assumed failure renders one of t e flow paths inoperable. The boration capability of either flow path is sufficient to provide a SHUTDOWN MARGIN as specified in the CORE OPERATING LIMITS REPORT from ex conditions after xenon decay and cooldown to 200* F. pected operating The maximum expected boron capability requirement occurs at EOL from full power equilibrium xenon conditions and requires 22,000 gallons of 7000 ppe borated water from oric acid storage tanks or a minimum contained volume of 477 000 pm boratedwaterfromtherefuelingwaterstoragetank(RW$T).gallonso 27oo-2Mo The limitation for a maximum of one centrifugal chargin pump to be OPERABLE and the Surveillance Requirement to verify all charg ng pumps except the required OPERABLE pump to be inoperable in MODES 4 5 an 6 provides assurancethatamassadditionpressuretransientcanber,elievedbyoperation of a single PORV or an RHR suction relief valve.

As a result of this, on1 one baron injection system is available. This i is acceptable on the basis of he stable reactivity condition of the reactor, the emergency power supply requirement for the OPERA 8LE charging pump and the additional restrictions prohibiting CORE ALTERATIONS and positive reactivity changes in the event the single injection system becomes inoperable.

SEABROOK - UNIT I B 3/4 1-2 Amendment No. 33

REACTIVITY CONTROL SYSTEMS BASES 3/4.1.2 BORATION SYSTEMS (Continued) .

The boron capability required below 200*F is sufficient to provide a SHUTDOWN MARGIN as specified in the CORE OPERATING LIMITS REPORT after xenon decay and cooldown from 200* F to 140 F. This condition requires a minimum contained volume of 6500 gallons of 7000 ppm borated waterS from the boric acid storage tanks or a minimum contained volume of 24,500 gallons of ppm borated water from the RWST.

_706]

gE Ihe contained water volume limits include allowance for water not available because of discharge line location and other physical characteristics.

l The limits on contained water volume and baron concentratiun of the RWST also ensure a pH value of between 8.5 and 11.0 for the solution recirculated within containment after a LOCA. This pH band minimizes the evolution of iodine and minimizes the effect of chloride and caustic stress corrosion on mechanical systems and components.

The OPERABILITY of one Boron Injection System during REFUELING ensures that this system is available for reactivity control while in MODE 6.

The limitations on OPERABILITY of isolation provisions for the Boron Thermal Regeneration System and the Reactor Water Makeup System in Modes 3, 4, 5, and 6 ensure that the boron dilution flow rates cannot exceed the value assumed in the transient analysis.

3/4.1.3 MOVABLE CONTROL ASSEMBLIES The specifications of this section ensure that: (1) acceptable power distri-bution limits are maintained, (2) the minimum SHUTDOWN MARGIN is maintained, and (3) the potential effects of rod misalignment on associated accident analyses are limited. OPERABILITY of the control rod position indicators is required to determine control rod positions and thereby ensure compliance with the control rod alignment and insertion limits. Verification that the Digit &l Rod Position Indicator agrees with the demanded position within i 12 steps at 24, 48, 120, and 228 steps withdrawn for the Control Banks and 18, 210, and 228 steps with-drawn for the Shutdown Banks provides assurances that the Digital Rod Position Indicator is operating correctly over the full range of indication. Since the Digital Rod Position Indication System does not indicate the actual shutdown rod

~

position between 18 steps and 210 steps, only points in the indicated ranges are picked for verification of agreement with demanded position.

The ACTION statements which permit limited variations from the basic requirements are accompanied by additional restrictions which ensure that the original design criteria are met. Misalignment of a rod requires measurement of peaking factors and a restriction in THERMAL POWER. These restrictions pro-

{ vide assurance of fuel rod integrity during continued operation. In addition, those safety analyses affected by a misaligned rod are reevaluated to confirm that the results remain valid-during future operation.

I SEABROOK - UNIT 1 B 3/4 1-3 Amendment No. 9

l z.III. - RetVne of Pronosed Chances i

See attached retype of proposed changes to Technical Specifications. The attached retype reflects the currently issued version of Technical Specifications. Pending Technical Specification changes !

or Technical Specification changes issued subsequent to this submittal are not reflected in the 1 enclosed retype. The enclosed retype should be checked for continuity with Technical Specifications prior to issuance.

7

l l

REACTIVITY CONTROL SYSTEMS BORATION SYSTEMS BORATED WATER SOURCES - SHUTDOWN LIMITING CONDITION FOR OPERATION I

3.1.2.5 As a minimum, one of the following borated water sources shall be OPERABLE:

a. A Boric Acid Storage System with:

1) A minimum contained borated water volume of 6,500 gallons,

2) A minimum boron concentration of 7000 ppm. and 1

3) A minimum solution temperature of 65 F. .

b. The refueling water storage tank (RWST) with:

1) A minimum contained borated water volume of 24.500 gallons,

2) A minimum boron concentration of 2700 ppm, and

3) A minimum solution temperature of 50 F.

APPLICABILITY: MODES 5 and 6.

ACTION:

With no borated water source OPERABLE, suspend all operations involving CORE ALTERATIONS or positive reactivity changes.

SURVEILLANCE REOUIREMENTS 4.1.2.5 The above required borated water source shall be demonstrated OPERABLE:

a. At least once per 7 days by:

1) Verifying the boron concentration of the water,

2) Verifying the contained borated water volume, and

3) Verifying the boric acid storage tank solution temperature when it is the source of borated water.

b. At least once per 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months by verifying the RWST temperature.

SEABROOK - UNIT 1 3/4 1-11 Amendment No.

REACTIVITY CONTROL SYSTEMS BORATION SYSTEMS BORATED WATER SOURCES - OPERATING LIMITING CONDITION FOR OPERATION 3.1.2.6 As a minimum, the following borated water sources shall be OPERABLE as required by Specification 3.1.2.2:

a. A Boric Acid Storage System with:

1) A minimum contained borated water volume of 22.000 gallons.

2) A minimum boron concentration of 7000 ppm, and

3) A minimum solution temperature of 65 F.

b. The refueling water _ storage tank (RWST) with:

1) A minimum contained borated water volume of 477.000 gallons. !

2) A boron concentration between 2700 and 2900 ppm.

I

3) A minimum solution temperature of 50 F. and

4) A maximum solution temperature of 98 F.

APPLICABILITY: MODES 1, 2. 3 and 4.

ACTION:

a. With the Boric Acid Storage System inoperable and being used as one of the above required borated water sources, restore the system 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 within the next 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months and borated to a SHUTDOWN MARGIN equivalent to at least the limit specified in the CORE OPERATING LIMITS REPORT (COLR) for the above MODES at 200 F: restore the 1

1 Boric Acid Storage 5 tem to OPERABLE status within the next 7 days or be in COLD SHUTDOWN within the next 30 hours3.472222e-4 days 0.00833 hours 4.960317e-5 weeks 1.1415e-5 months .

b. With the RWST ino]erable, restore the tank to OPERABLE status within 1 hour1.157407e-5 days 2.777778e-4 hours 1.653439e-6 weeks 3.805e-7 months or ae in at least HOT STANDBY with the next 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months and in COLD SHUTDOWN within the following 30 hours3.472222e-4 days 0.00833 hours 4.960317e-5 weeks 1.1415e-5 months .

SEABROOK - UNIT 1 3/4 1-12 Amendment No. 9.

3/4.5 EMERGENCY CORE COOLING SYSTEMS 3/4.5.1 ACCUMULATORS

l HOT STANDBY. STARTUP. AND POWER OPERATION i LIMITING CONDITION FOR OPERATION 3.5.1.1 Each Reactor Coolant System (RCS) accumulator shall be OPERABLE with: ,

l

a. The isolation valve open and power removed.

b, A contained borated water volume of between 6121 and 6596 gallons.

c. A boron concentration of between 2600 and 2900 ppm, and

d. A nitrogen cover-pressure of between 585 and 664 psig.

APPLICABiLi ff: MODES 1. 2. and 3*

ACTION: ,

a. With one accumulator inoperable. except as a result of a closed isolation valve. restore the inoperable accumulator to OPERABLE status within 8 hours9.259259e-5 days 0.00222 hours 1.322751e-5 weeks 3.044e-6 months or be in at least HOT STANDBY within the next >

6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months and reduce pressurizer pressure to less than 1000 psig within the following 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months .

b. With one accumulator inoperable due to the isolation valve being closed, either immediately open the isolation valve or be in at least HOT STANDBY within 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months and reduce pressurizer pressure to less than 1000 psig within the following 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months .

c. With one pressure or water level channel inoperable per accumulator. return the inoperable channel to OPERABLE status within 30 days or be in at least HOT STANDBY within the next 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months and in HOT SHUTDOWN within the following 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months , i

d. With two pressure channels or two water level channels inoperable per accumulator, immediately declare the affected accumulator (s) :

inopt.rable.

I SURVEILLANCE REQUIREMENTS i

4.5.1.1 Each accumulator shall be demonstrated OPERABLE: I

a. At least once per 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months by:

1) Verifying the contained borated water volume and nitrogen cover-pressure in the tanks, and !

Pressurizer pressure above 1000 psig.

SEABROOK - UNIT 1 3/4 5-1 Amendment No. 30.

} 4 -'

BORON INJECTION SYSTEM ;

t 3/4.5 4 REFUELING WATER STORAGE TANK

.. i.

LIMITING CONDITION FOR OPERATION i

3.5.4 The refueling water storage tank (RWST) shall be OPERABLE with: ,

a. A minimum contained borated water volume of 477,000 gallons.

b. A boron concentration between 2700 and 2900 ppm of boron. !

c. A minimum solution temperature of 50 F. and .

d. A maximum solution temperature of 98 F.

APPLICABILITY: MODES 1, 2, 3. and 4.

ACTION:

i With the RWST inoperable. restore the tank to OPERABLE status within 1 hour1.157407e-5 days 2.777778e-4 hours 1.653439e-6 weeks 3.805e-7 months or be in at least HOT STANDBY within 6 hours6.944444e-5 days 0.00167 hours 9.920635e-6 weeks 2.283e-6 months and in COLD SHUTDOWN within the ;

following 30 hours3.472222e-4 days 0.00833 hours 4.960317e-5 weeks 1.1415e-5 months . l l

SURVEILLANCE REQUIREMENTS )

4.5.4 The RWST shall be demonstrated OPERABLE:

a. At least once per 7 days by:

1) Verifying the contained borated water volume in the tank, and

2) Verifying the boron concentration of the water.

b. At least once per 24 hours2.777778e-4 days 0.00667 hours 3.968254e-5 weeks 9.132e-6 months by verifying the RWST temperature.

l i

i SEABROOK - UNIT 1 3/4 5-11 Amendment No.

RfACTIVITY CONTROL SYSTEMS

' BASES' B0 RATION CONTROL 3/4.1.1.3' MODERATOR TEMPERATURE COEFFICIENT (Continued) l The surveillance requirements for measurement of the MTC at the beginning :

and near the end of the fuel cycle are adequate to confirm that the MTC remains within its limits since this coefficient changes slowly due principally to the reduction in RCS boron concentration associated with fuel burnup. ;

Prior to initial operation above 5% RATED THERMAL POWER after each fuel loading. the MTC is measured as required by Surveillance Requirement 4.1.1.3.a. .

A measurement bias is derived from the difference between test measurement and .

test prediction. All predicted values of MTC for the cycle are conservatively '

corrected based on measurement bais. The corrected predications are then compared to the maximum upper limit of Technical Specification 3.1.1.3.

Control rod withdrawal limits are established, if required, to assure all i corrected values of predicted MTC will be less positive than the maximum upper limit required by Technical Specification 3.1.1.3.

3/4.1.1.4 MINIMUM TEMPERATURE FOR CRITICALITY ,

i This specification ensures that the reactor will not be made critical with the Reactor Coolant System average temperature less than 551 F. This '

limitation is required to ensure: (1) the moderator temperature coefficient is within its analyzed temperature range. (2) the trip instrumentation is within its normal operating range. (3) the .

OPERABLE status with a steam bubble, pressurizer and is capable (4) the reactor of being vessel in an its is above minimum RT, temperature.

3/4.1.2 BORATION SYSTEMS The Boron Injection System ensures that negative reactivity control is The com ,

available during each mode of facility operation.(1) borated water sources.ponents (2) charging pumps. required to p(erform this flow

3) separate function include:

paths. (4) boric acid transfer pumps, and (5) an emergency power supply from OPERABLE diesel generators.

With the RCS in MODES 1. 2. or 3. a minimum of two boron injection flow paths are required to ensure single functional capability in the event an ,

assumed failure renders one of the flow paths inoperable. The boration :

capability of either flow path is sufficient to provide a SHUTDOWN MARGIN as 2 specified in the CORE OPERATING LIMITS REPORT from expected operating conditions after xenon decay and cooldown to 200 F. The maximum expected boron capability requirement occurs at EOL from full power equilibrium xenon ,

conditions and requires 22.000 gallons of 7000 ppm borated water from the boric acid storage tanks or a minimum contained volume of 477.000 gallons of 2700-2900 ppm borated water from the refueling water storage tank (RWST).

The limitation for a maximum of one centrifugal charging pump to be OPERABLE and the Surveillance Requirement to verify all charging pumps except the required OPERABLE pump to be inoperable in MODES 4. 5. and 6 provides-assurance that a mass addition pressure transient can be relieved by operation of a single PORV or an RHR suction relief valve.

As a result of this, only one boron injection system is available. This is acceptable on the basis of the stable reactivity condition of the reactor. .

the emergency power supply requirement for the OPERABLE charging pump and the additional restrictions prohibiting CORE ALTERATIONS and positive reactivity changes in the event the single injection system becomes inoperable.

SEABROOK - UNIT 1 B 3/4 1-2 Amendment No. 9 32.

REACTIVITY CONTROL SYSTEMS iBASES 3/4.1.2 BORATION SYSTEMS (Continued)

The boron capability required below 200 F is sufficient to provide a SHUTDOWN MARGIN as specified in the CORE OPERATING LIMITS REPORT after xenon decay and cooldown from 200 F to 140 F. This condition requires e mhomum contained volume of 6500 gallons of 7000 ppm borated water from the boric acid storage tanks or a minimum contained volume of 24.500 gallons of 2700 ppm borated water from the RWST.

The contained water volume limits include allowance for water not available because of discharge line location and other physical characteristics.

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

The OPERABILITY of one Boron Injection System during REFUELING ensures that this system is available for reactivity control while in MODE 6.

The limitations on OPERABILITY of isolation provisions for the Boron !

Thermal Regeneration System and the Reactor Water Makeup System in Modes 4. 5.

and 6 ensure that the boron dilution flow rates cannot exceed the value assumed ;

in the transient analysis. l 3/4.1.3 MOVABLE CONTROL ASSEMBLIES i The specifications of this section ensure that: (1) acceptable power distribution limits are maintained. (2) the minimum SHUTDOWN MARGIN is maintained, and (3) the potential effects of rod misalignment on associated accident analyses are limited. OPERABILITY of the control rod Josition indicators is required to determine control rod positions and t1ereby ensure compliance with the control rod alignment and insertion limits. Verification that the Digital Rod Position Indicator agrees with the demanded position within i 12 steps at 24. 48. 120. and 228 steps withdrawn for the Control Banks and 18, 210. and 228 steps withdrawn for the Shutdown Banks provides assurances that the Digital Rod Position Indicator is o)erating correctly over the full range of indication. Since the Digital Rod )osition Indication System does not indicate the actual shutdown rod position between 18 steps and 210 steps, only points in the indicated ranges are picked for verification of agreement with demanded position.

The ACTION statements which permit limited variations from the basic requirements are accompanied by additional restrictions which ensure that the original design criteria are met. Misalignment of a rod requires measurement of peaking factors and a restriction in THERMAL POWER. These restrictions provide assurance of fuel rod integrity during continued operation. In addition, those safety analyses affected by a misaligned rod are reevaluated to confirm that the results remain valid during future operation.

SEABROOK - UNIT 1 B 3/4 1-3 Amendment No. E 21

J V.

Determination of Sienificant IIazards for Proposed Chances

1. The proposed changes do not involve a significant increase in the probability or consequences of an accident previomly evaluated The proposed changes involve the boron concentrations in borated water sources and the post-LOCA time for switchover to hot leg recirculation for Cycle 5 and future cycles. No changes are made to the design or manner of operation of structures, systems or components.

The boron concentrations in borated water sources affect the Shutdown Margin following most plant transients and affect the consequences of a boron dilution incident. The proposed changes in boron concentrations assure the post event Shutdown Margin required by Technical Specifications will be met and the consequences of a boron dilution event remain as previously evaluated. The proposed upper limit on boron concentration in the RWST and Accumulators also ensures that the boron solubility limit will not be approached in these volumes. The proposed changes in boron concentrations do not affect the probability of previously evaluated accidents.

The proposed changes to the boron concentration limits in accumulators and the RWST continue to assure an acceptable range of pil of between 8.5 and 11.0 for the solution recirculated within containment after a LOCA.

The post-LOCA time for switchover to hot leg recirculation is changed from 18 hours2.083333e-4 days 0.005 hours 2.97619e-5 weeks 6.849e-6 months to 9 hours1.041667e-4 days 0.0025 hours 1.488095e-5 weeks 3.4245e-6 months to assure the core region does not approach the boron precipitation limit. The available hot leg recirculation flow is sufficient to remove decay heat at 9 hours1.041667e-4 days 0.0025 hours 1.488095e-5 weeks 3.4245e-6 months . The change in hot leg switchover time does not increase the previously calculated consequences of a LOCA.

Therefore, the proposed changes do not involve an increase in the probability or consequences of an accident previously evaluated.

2. The proposed changes do not create the possibility of a new or different kind ofaccidentfrom any accident previously evaluated As described above, the changes proposed in this LAR involve changes in the boron concentrations in borated water sources and the post-LOCA time for switchover to hot leg recirculation for Cycle 5 and future cycles. These changes do not cause the associated structures, systems, or components to be operated outside their original design envelope. No changes are made to the design or manner of operation of structures, systems, or components. No new failure mechanisms are introduced. Therefore, the proposed changes do not create the possibility of a l new or difTerent accident from any accident previously evaluated.

3. The proposed changes do not result in a significant reduction in the margin of safety.

The margin of safety is defined by: 1) the acceptance criteria for the design of associated structures, systems, or components; and 2) the acceptance criteria for previously evaluated accidents.

As previously stated, the proposed changes do not cause the associated structures, systems or components to be operated outside their original design envelope.

8

. Similarly the proposed changes assure that the acceptance criteria for previously evaluated ,

accidents continue to be met for Cycle 5 and future cycles. The proposed changes in boron concentrations assure the post event Shutdown Margin required by Technical Specifications will ;

continue to be met and the consequences of a boron dilution event remain as previously evaluated.

The proposed upper limit on boron concentration in the RWST and Accumulators also ensures that the boron solubility limit will not be approached in these volumes.

The proposed changes to the boron concentration limits in Accumulators and the RWST continue ,

to assure an acceptable range of pil of between 8.5 and 11.0 for the solution recirculated within containment after a LOCA. The change in post-LOCA hot leg switchover time from 18 to 9 hours1.041667e-4 days 0.0025 hours 1.488095e-5 weeks 3.4245e-6 months assures the core region does not approach the boron precipitation limit. The available hot leg recirculation flow is sufficient to remove decay heat at nine hours. The core will remain suberitical in the cold condition and amenable to long term cooling following a LOCA.

Therefore, the proposed changes do not result in a reduction in the margin of safety.

i

)

I l

9

_. ~

f

,V,. ' Proposed Schedule for License Amendment Issaance and Effectiveness North Atlantic requests NRC review of License Amendment Request 95-01 and issuance of a-license amendment having immediate effectiveness by November 1,1995.

i.

u.

f .,

t j

I c

1

'I i

( .-

10

e 6 1

gVI. b Environmental Impact Assessment North Atlantic has reviewed the proposed license amendment against the criteria of 10CFR51.22 1 for environmental considerations. The proposed changes do not involve a significant hazards consideration, nor increase the types and amounts of effluent that may be released offsite, nor significantly increase individual or cumulative occupational radiation exposures. Based on the foregoing, North Atlantic concludes that the proposed change meets the criteria delineated in I 10CFR51.22(c)(9) for a categorical exclusion from the requirements for an Environmental Impact i

Statement.-

t l

i i

1 s

9 f

I i

l 1I .

i l

ML20085L116

Text

Navigation menu

Search