ML20081J630

Proposed Tech Specs Re Addition of New Statement That Would Allow 72 H Outage Time for One Accumulator to Be Inoperable

ML20081J630
Person / Time
Site:	Wolf Creek
Issue date:	03/24/1995
From:	WOLF CREEK NUCLEAR OPERATING CORP.
To:
Shared Package
ML20081J626	List: ML20081J623 ML20081J630
References
NUDOCS 9503280076
Download: ML20081J630 (6)

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Attachment IV to CO 95-0001?

Page 1 of:6

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. z; ATTACHMENT IV PROPOSED TECHNICAL SPECIFICATION CHANGES

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9503280076 950324 PDR-ADOCK 05000482 P. -

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Attachment IV to CO 95-0001 Page 2 of 6 3/4.5 EMERGENCY CORE COOLING SYSTEMS 3/4 51 ACCUMULATORS LIMITING CONDITION FOR OPERATION 3.5.1 Each Reactor Coolant System accumulator shall be OPERABLE with:

a. The isolation valve open and power removed,

b. A contained borated water volume of between 6122 and 6594 gallons,

c. A boron concentration of between 2300 and 2500 ppm, and

d. A nitrogen cover-pressure of between 585 and 665 psig.

APPLICABILITY: MODES 1,2, and 3*.

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ERT "A"

, for reasons other tha ACTION a.,

b.

With one accumulator inoperable, s~ ;ti Fr:Tu!! Of : e cred

re'2t!cn v !ve, restore the inoperable accumulator to OPERABLE 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and reduce {,or be in at least HOT STANDBY within the next status within thou

,RC ressure to less than 1000 psig within the following 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />.

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b. Y!:th One era" u'2ter n0p^rab!e due to the !!c'2t!0n v:!v being i

c'ered, either :- ef rie'y Open the !*r'rt!cn ve've er '-in et

! : t HOT STANO9Y t""Nn S hour: nd reduce RCS pre :ure4aless then 1'" 79; ""- the fe"Owing S heure.

SURVEILLANCE REQUIREMENTS 4.5.1.1 Each accumulator shall be demonstrated OPERABLE:

a. At least once per 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> by:

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1) Verifying, by the abeence of elarn% the contained borated water volume and nitrogen cover-pressure in the tanks, and are within their limits

2) Verifying that each accumulator isolation valve is open.

• Pressurizer pressure above 1000 psig I

l WOLF CREEK - UNIT 1 3/4 5-1 Amendment No. 44,23 j

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Attachment IV to CO 95-0001 Page 3 of 6 l

INSERT "A"

With one accumulator inoperable due to boron concentration not within limits, either restore the boron concentration to within the above limits within 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> 1

or be in at least HOT STANDBY within the next 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and reduce RCS pressure to less than 1000 psig within the following 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />.

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Attachment IV to CO 95-0001 Page 4 of 6 EMERGENCY CORE COOLING SYSTEMS SURVEILLANCE REQUIREMENTS (Continued)

b. At least once per 31 days and within 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> after each solution volume increase of greater than o: equal to 70 gallons by ri in the boron concentration of th_e accumgl_ator solution.

his surveillance e not reqUlrMoe volume increase makeup source is the RWST and the RWST has not been diluted since verifying that its boron concentration is within limits of Specification 3.5.5.

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c. At least once per 31 days when the RCS pressure is above 1000 psig by verifying that the circuit breaker supplying power to the isolation valve operator is open.

444-3--Each Mc'me! !? " 2ter !:;;!:nd pre swe c'enne! che!! be demombatedOPERABLE at 'e2:t enee per 18 menthe by-the Mermen = cf a CHANML CAL!9RATKE WOLF CREEK - UNIT 1 3/4 5-2

Attachment IV to CO 95-0001 Page 5 of 6 3/4.5 EMERGENCY CORE COOLING SYSTEMS

.B. sASES 1

3/4 5.1 ACCUMULATORS The OPERABILITY of each Reactor Coolant System (RCS) accumulator ensures that a sufficient volume of borated water will be immediately forced into the core through each of the cold legs in the event the RCS pressure fails below the pressure of the accumulators. This initial surge of water into the core i

provides the initial cooling mechanism during large RCS pipe ruptures.

The limits on accumulator volume, boron concentration and pressure ensure that the assumptions used for accumulator injection in the safety analysis are met.

The accumulator power operated isolation valves are considered to be I

" operating bypasses" in the context of IEEE Std. 279-1971, which requires that bypasses of a protective function be removed automatically whenever permissive conditions are not met in addition, as these accumulator isolation valves fail to meet single failure criteria, removal of power to the valves is required.

INSERT "B"

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Th^ ! m": for Op^re!!On r"h en errrrr' rte'inep rrb!? for eny rreren exc^^t en Me'et en v:!r: c'ered r"m!:n the !:m: experu Of'he ?!:n!t :

L.OCA : :nt ^^^" ring cencu~ent Mh fr!'u'e Of en eddf^^ ! eccume!:ter whichar. y :: u!!!n unscrepteb!e peth c'edding temperatures. 'f: r!cred ire!st!cn v !v cennet be ! m^d!:t:!y epened, the fu!! car-'"?y Of One accumutalcr !: net eve!!:b! nd prempt ec'ien i: re';u! red te p'ere the ter-*er in-a4nodewhere th!: reprb"!!y !: not r^^ui ed.

3/4 5 2. 3/4.5 3. and 3/4.5.4 ECCS SUBSYSTEMS t

The OPERABILITY of two independent ECCS subsystems ensures that sufficient emergency core coofing capab;lity will be available in the event of a LOCA i

assuming the loss of one subsystem through any single failure consideration.

Either subsystem operating in conjunction with the accumulators is capable of supplying sufficient core cooling to limit the peak cladding temperatures within acceptable limits for all postulated break sizes ranging from the double ended break of the largest RCS cold leg pipe downward. In addition, each ECCS subsystem provides long-term core cooling capability in the recirculation mode during the accident recovery period.

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

I WOLF CREEK-UNIT 1 B 3/4 5-1 1

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' Attachment IV to Co 95-0001 Page 6 of 6 t

INSERT "B"

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The allowed outage time limit for operation with one accumulator inoperable due to boron concentration not within limits reflects the fact that no credit is taken in the accident analysis for boron concentration in the accumulators during-i the LOCA blowdown phase.

Injection of borated water provides the fluid medium e

for. heat transfer from t.he core and prevents excessive clad temperatures,

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contributing to the filling of the reactor vessel downcomer.

The downcomer water elevation head provides the driving force required for the reflooding of the

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reactor core.

Negative reactivity is initially a function of.the void formation in the core, one accumulator below the minimum boron concentration limit will l

have no effect on available ECCS water and an insignificant effect on core subcriticality during reflood.

Boiling of ECCS water in the core during reflood concentrates boron in the saturated liquid that remains in - the core.

Boron concentration during the sump recirculation' phase is dominated by the RWST. boron f

concentration.

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Technical Specification 4.5.1.2, which required the performance of a channel

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calibration of each accumulator water level and pressure channel once per 18

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months, was relocated to the Updated Safety Analysis Report.

This was accomplished in accordance with the recommendations of Generic Letter 93-05 and NUREG-1366.

These recommendations were based on the recognition that accumulator j

instrumentation operability is not directly related to the capability of the accumulators to perform their safety function.

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