ML20086Q884

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TS Change Request NPF-38-170 to License NPF-38,modifying TS 3.5.1 to Allow Up to 24 H to Restore Safety Injection Tank (SIT) Operability If SIT Inoperable Due to Level &/Or Pressure Outside Prescribed Limits
ML20086Q884
Person / Time
Site: Waterford Entergy icon.png
Issue date: 07/26/1995
From: Barkhurst R
ENTERGY OPERATIONS, INC.
To:
NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
Shared Package
ML20086Q886 List:
References
W3F1-95-0089, W3F1-95-89, NUDOCS 9507280233
Download: ML20086Q884 (9)


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b 504 739 6661 Ross P. Barkhurst Vro fe t:mt Operem V,r.it.d ej 3

.W3F1-95-0089 h A4.05 PR July 26,1995 U.S. Nuclear Regulatory Commission Attn: Document Control Desk Washington, D.C. 20555 i

Subject:

Waterford 3 SES Docket No. 50-382 License No. NPF-38 l Technical Specification Change Request NPF-38-170 ]

Gentlemen: l The attached description and safety analysis supports a change to the  !

I Waterford 3 Technical Specifications (TS). The subject change request modifies specification 3.5.1 to allow up to 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> to restore Safety.

Injection Tank (SIT) operability if the SIT is inoperable due to level and/or pressure outside prescribed limits.. The proposed change would also allow up to 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> to restore SIT operability if the SIT is inoperable due to instrument failure. This amendment is a collaborative effort of participating Combustion Engineering Owners Group' members based on a review of plant operations, deterministic and design basis considerations, and plant risk, as well as previous generic studies and conclusions drawn by NRC staff and  !

contained within NUREG-1366, " Improvements to Technical Specifications Surveillance Requirements," and NUREG-1432, Revision 0, " Standard Technical Specifications for Combustion Engineering (CE) Plants." Joint Application Report CE NPSD-994, referenced herein in support of this change, has been submitted to the staff for review and approval under separate letter CE0G-95-344 dated July 10, 1995.

she proposed change has been evaluated in accordance with 10CFR50.91(a)(1) vsing criteria in 10CFR50.92(c) and it has been determined that this change involves no significant hazards considerations. The bases for these determinations are included in the attached submittal.

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.e Technical Specification Change Request NPF-38-170 W3F1-95-0089 Page 2 July 26, 1995 Waterford 3 requests that the implementation date for this change be within 60 days of NRC issuance of the amendment to allow for distribution and procedural revisions necessary to implement this change. Although this request is neither exigent nor emergency, your prompt review is requested.

Should you have any questions or comments concerning this request, please contact Paul Caropino at (504)739-6692.

Very truly yours, N

R.P. Barkhurst Vice President, Operations Waterford 3 RPB/PLC/ssf

Attachment:

Affidavit NPF-38-170 cc: L.J. Callan, NRC Region IV C.P. Patel, NRC-NRR R.B. McGehee l N.S. Reynolds i NRC Resident Inspectors Office ,

Administrator Radiation Protection Division I (State of Louisiana) I American Nuclear Insurers l l

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.. ,..- . NUCLEAR REGULATORY COMMISSION In the' matter of- )

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-Entergy Operations, Incorporated ). Docket No. 50-382- i Waterford 3 Steam Electric Station )  !

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i AFFIDAVIT j

, R.P. Barkhurst, being duly sworn, hereby deposes and says that he is Vice  !

President Operations - Waterford 3 of Entergy Operations, Incorporated; that l he is duly authorized to sign and file with the Nuclear Regulatory Commission  :

the attached Technical Specification Change Request NPF-38-170; that he is  !

familiar with the content thereof; and that the matters set forth therein are l true and correct to the best of his knowledge, information and belief. i R.P. Barkhurst ~

i Vice President Operations - Waterford 3 STATE OF LOUISIANA )

) ss l PARISH OF ST. CHARLES )

H Subscribed and sworn to before me, a Notary Public in and for the Parish and -1 State above named this 2.fo* day of - d u t'i' , 1995.

JLEEQ Notary Public My Commission expires p < m 6'M .

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.. j DESCRIPTION AND SAFETY ANALYSIS OF PROPOSED CHANGE NPF-38-170  !

The action statements for LCO 3/4.5.1 Safety Injection Tanks have been j modified to reflect those operability aspects as prescribed by CE Standard ,

Technical Specifications NUREG-1432. Specifically, reference to the SIT '

isolation valve has been removed and boron concentration is addressed. The action requirements are further revised to address the inability to verify SIT level and pressure (i.e. inoperable instrumentation) and prescribe the extended allowed outage times (A0Ts) proposed in CEN NPSD-994. I Revised actions (a) and (b) propose a 72 hour8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> A0T when a single SIT is declared inoperable due to baron concentration not within the limits or the l inability to verify level or pressure. Action (c) proposes a 24 hour2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> A0T when the' SIT is declared inoperable for reasons other then actions (a) or (b).

The proposed change also incorporates a clarification to TS surveillance 4.5.1.b pursuant to a recommendation in Generic Letter 93-05.

Existina Snecification See Attachment A Proposed Specification See Attachment B i

packaround The SITS are passive pressure vessels partially filled with borated water and pressurized with a cover of nitrogen gas to facilitate injection into the reactor vessel during the blowdown phase of a large break loss of coolant accident (LOCA). This action provides inventory to assist in accomplishing the refill stage following blowdown. The SITS also provide reactor coolant system (RCS) makeup for the larger small break LOCAs.

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Each SIT is piped into an associated RCS cold leg via an emergency core cooling system (ECCS) line also utilized by high pressure safety injection and  !

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low pressure safety injection (HPSI and LPSI). Each SIT is isolated from the RCS, during full pressure operations, by two series check valves. 'Each SIT ,

also has a normally deenergized open motor operated isolation valve utilized '

to isolate the SIT from the RCS during normal cooldown and depressurization ,

evolutions. The SITS are described in the Waterford'3 Updated Final Safety Analysis Report 6.3.2.2.1.  :

The SIT gas pressure and volume, water volume, and outlet pipe size are i designed to allow three of the four SITS to inject the necessary volume to j keep clad melt and zirc-water reaction within design assumptions following a l design basis LOCA. The design assumes the loss of inventory from one SIT i through a the LOCA break. j l

Description  !

Industry operating experience has demonstrated that many of the causes of SIT inoperability have been diagnosed and' corrected within a relatively short period of time, but often longer than the existing one hour A0T. In several l cases, the diagnosis of an inoperable SIT has resulted in plant shutdowns. A  ;

review of this operating experience, when tempered with current probabilistic  ;

safety analysis (PSA) applications, led to questioning the risk differential j between application of the current technical specification (TS) action  ;

statements, with their attendant transient risks, and an extended A0T with one l SIT inoperable. j If a single SIT were to be diagnosed as inoperable due to tank level or  !

pressure or both being outside the limits established in the Waterford 3 TS l 3.5.1, the current action statement would require the tank to be restored to  !

operable status within one hour or the. plant to be in at least hot standby l within the next 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br /> and in hot shutdown within the following 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />. If '

a single SIT were diagnosed as inoperable due to the associated isolation valve being closed, the current action statement requires the valve to be  ;

immediately opened or be in at least hot standby within I hour and in hot shutdown within the next 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br />. The proposed change to TS would allow 72 i hours to restore SIT operability if the cause of inoperability is due to boron concentration not being within the limits or an inability to verify level and pressure. A single SIT declared inoperable for any other reason would have to be returned to operable status within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> under the provisions of the proposed change.

4 The Combustion Engineering Owners Group (CE0G) " Joint Applications Report for  ;

Safety Injection Tank A0T/STI Extension," CE NPSD-994, has demonstrated risk calculations associated with an A0T extansion from one hour to 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />. The results of the analyses indicate that the single and yearly A0T risk contributions are negligible, and the average core damage frequency (CDF) is virtually unchanged.

A similar risk assessment was performed to evaluate " transition risk."

Transition risk represents the risk associated with reducing power and going to hot or cold shutdown following equipment failure. The results of this analysis indicate that the core damage probability (CDP) attributable to transition risk is larger than the CDP associated with continued operation of the plant at power with one SIT inoperable for the proposed A0T.

The current Waterford 3 TS make no differentiation between a SIT that is inoperable due to actual inventory or gas pressure discrepancies and a SIT whose inventory or gas pressure cannot be verified due to instrumentation malfunction. The proposed change will allow continued operation for up to 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> for a single SIT is deemed inoperable due solely to malfunctioning level instrumentation or pressure instrumentation. Because this instrumentation provides no safety actuation, it is reasonable to extend the allowable outage time since the SIT is available to perform its safety function during this time even though technically inoperable. This change would result in a negligible increase in risk. This proposed change is in accordance with the '

provisions of NUREG-1366, " Improvements to Technical Specifications  ;

Surveillance Requirements" and Generic letter 93-05 "Line Item Improvements to Reduce Surveillance Requirements for Testing During power Operation."

It is the conclusion of the study that the overall plant impact will be either risk beneficial, or at the very least, risk neutral.

Safety Analysis The proposed change described above shall be deemed to invclve a significant hazards consideration if there is a positive finding in any of the following areas: j

1. Will operation of the facility in accordance with this proposed change involve a significant increase in the probability or consequences of an accident previously evaluated?

1 Response: No i

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The SITS are passive components in the Emergency Core Cooling System.  !

The SITS are not an accident initiator in any accident previously l evaluated. - Therefore, this change does not involve an increase in the l probability. of an accident previously evaluated SITS wert designed to mitigate the consequences of Loss of Coolant l Accidents (LOCA). These proposed changes do not affect any of the assumptions used in deterministic LOCA analysis. Hence the consequences i of accidents previously evaluated do not change.

In order to fully evaluate the affect of the SIT A0T extension, probabilistic safety analysis (PSA) methods were utilized. The results l j of these ar:alyses show no significant increase in the core damage  :

frequency. As a result, there would be no significant increase in the consequences of an accident previously evaluated. These analyses are detailed in CE NPSD-994, Combustion Engineering Owners Group " Joint Applications Report for Safety Injection Tank A0T/STI Extension."

The changes pertaining to boron sampling requirements and SIT inoperability based solely on instrumentation malfunction do not involve i a significant increase in the consequences of an accident as evaluated j and swiorsed by the NRC in NUREG-1366, " Improvements to Technical Specifications Surveillance Requirements." These changes are applicable  ;

to Waterford 3. l i

The A0T extension based upon boron concentration outside the prescribed l limits does not involve a significant increase in the consequences of an  !

accident as evaluated and approved by the NRC in NUREG-1432, " Standard Technical Specifications for Combustion' Engineering Plants." These changes are applicable to Waterford 3. i I

Therefore, the proposed change will not involve a significant increase '

in the probability or consequences of any accident previously evaluated.

2. Will operation of the facility in accordance with this proposed change create the possibility of a new or different type of accident from any accident previously evaluated?

Response: No. ,

1 This proposed change does nc,t change the design, configuration, or method of operation of the plant. Therefore, the proposed change will i not create the possibility of a new or different kind of accident from any accident previously evaluated.

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-~3.- Will operation of the facility in accordance with this proposed change i involve a significant reduction ~in a margin of safety?  ;

Response: No j I

n: -The proposed changes do not affect the limiting conditions for operation  ;

or their bases that are used in the deterministic analyses to establish i the margin of safety. PSA evaluations were 'used to evaluate these  :

changes. These evaluations demonstrated that the changes are either risk neutral or risk beneficial. These evaluations are detailed in CE E NPSD-994. Therefore, the proposed change will not involve a significant

  • L reduction in a margin of safety.

1 Safety and Sianificant Hazards Determination Based on the above safety analysis, it is concluded that: (1) the proposed change does not constitute a significant hazards consideration as defined by.

10CFR50.92; and (2) there is a reasonable assurance that the health and safety: -l of.the public will not be endangered by the proposed change; and (3) this I action will not result in a condition which significantly alters the impact of the station on the environment as described in the NRC final environmental statement.

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