RBG-26988, Application for Amend to License NPF-47,revising Tech Spec Surveillance Requirements for Standby Svc Water Sys UHS Instrumentation.Justification & NSHC Encl

Application for Amend to License NPF-47,revising Tech Spec Surveillance Requirements for Standby Svc Water Sys UHS Instrumentation.Justification & NSHC Encl

ML20236Q153
Person / Time
Site:	River Bend
Issue date:	11/13/1987
From:	Deddens J GULF STATES UTILITIES CO.
To:	NRC OFFICE OF ADMINISTRATION & RESOURCES MANAGEMENT (ARM)
Shared Package
ML20236Q156	List: ML20236Q169 RBG-26988, Application for Amend to License NPF-47,revising Tech Spec Surveillance Requirements for Standby Svc Water Sys UHS Instrumentation.Justification & NSHC Encl
References
RBG-26988, NUDOCS 8711190215
Download: ML20236Q153 (7)

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. GULF STATES . UTILITIES. COMPANY November 13, 1987 RBG- 26988 .  ;

File No. G9.5, G9.8.9.6 U. S. Nuclear Regulatory Commission; Document Control Desk

' Washington, D.C. 20555 Gentlemen:

River Bend Station - Unit 1 Docket No. 50-458'

' Gulf . States .. Utilities. (GSU). Company hereby files an amendment to the

' River Bend Station Unit 1.Fac111ty Operating License NPF-47, pursuant-.

to 10CFR50.90.- This application is filed to fulfill the requirements of the NRC. Staff _ Safety Evaluation Report (SER) dated September 28,

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1987 .(RBG-36319) for. Ultimate Heat Sink instrumentation installed pursuant; to License-Condition 2(C)(9) of Facility Operating License NPF-47 and Supplement 3 of the River Bend SER (NUREG-0989), Section 9.2.5. The design has been previously discussed in GSU's submittal'of June 29, 1987 (RBG-26184) and evaluated by the NRC in their SER. The attached information includes proposed revisions to the River Bend

- Station technical specification and: Justifications for this change.

Pursuant to 10CFR170.12, GSU has enclosed a check in the amount of one

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hundred fifty dollars ($150.00) for the license amendment application  ;

fee. Your prompt attention to.this application is appreciated.

Sincerely, 8711190215 871113 PDR ADOCK 05000458 p PDR J. C. Deddens Sr. Vice-President River Bend Nuclear Group Attachment I

cc: U.S. Nuclear Regulatory Commission i 611 Ryan Plaza Drive, Suite 1000 Arlington, TX 76011 Senior Resident Inspector Post Office Box 1051 [COf

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St. Francisv111e, LA 70775 f I

REC D V-fil0 LIV ci1ECK

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P . UNITED STATES OF AMERICA I

NUCLEAR REGULATORY. COMMISSION p

1' STATE OF LOUISIANA-' )

PARISH.OF. WEST FELICIANA )

In the Matter of- ) . Docket No. 50-458-50-459 GULF STATES UTILITIES COMPANY )

(River Bend Station,

! Unit 1)

AFFIDAVIT u

J. C. :Deddens, being duly sworn, states that he is a Senior Vice President of Gulf States Utilities Company; that he. is authorized on the part of said company to sign and file with.the Nuclear Regulatory Commission the documents

. attached hereto; and that all such documents are true and correct to. the best of his- knowledge, information and belief.

/

J. C. dddens Subscribed and sworn to before me, a Notar Public in and for the State and Parish above named, this [ I day of A/6 VPnThcr , 19 N .

/ h1h lt /+

/Joan W. Middlbbrooks  !

(/ Notary Public in and for West Feliciana Parish, Louisiana My Commission is for Life.

ATTACHMENT 1 GULF STATES UTILITIES COMPANY RIVER BEND STATION DOCKET 50-458/ LICENSE NO. NPF-47 Ultimate Heat Sink Temperature Monitoring Licensing Document Involved Technical Specifications Item 4.7.1.2 Page 3/4 7-4 REASON FOR REQUEST A proposed change is being requested in accordance with 10CFR50.90 to revise the Technical Specification (TS) Surveillance Requirements for the Standby Service Water system Ultimate Heat Sink (UHS) water temperature. Gulf States Utilities (GSU) proposes this change request will fulfill the requirements of the NRC Staff Safety Evaluation Report (SER) dated September 28, 1987 for instrumentation installed pursuant to License Condition 2(C) (9) of Facility Operating License NPF-47 and Supplement 3 of the River Bend SER (NUREG-0989), Section 9.2.5. The system is capable of measuring the temperature and providing indication and alarm in the Main Control Room and locally as previously discussed in GSU's submittal of June 29, 1987 (RBG-26184) and evaluated by the NRC in their SER. The present surveillance requires verifying the water temperature to be less than or equal to 82*F every 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> and every 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> when the last recorded temperature was greater than or equal to 75*F and every 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> when the temperature was greater than or equal to 80*F. The proposed change.would maintain the surveillance to verify the temperature less than or equal to 82*F every 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />, and relax the increased surveillance frequency when the enhanced instrumentation is operable. In addition, the change will provide guidance on the minimum number of instruments required to perform the surveillance.

DISCUSSION The UHS function is to provide shutdown cooling and decay heat removal capability following a Design Basis Accident. By restricting the water temperature to 82*F or less prior to the event, the ability of the UHS to satisfy GDC-44 is assured as documented in section 9.2.5 of the Safety Analysis Report (SAR). The accident monitoring of Standby Service Water temperature is accomplished by Class 1E instrumentation as required by Regulatory Guide 1.97. The normal UHS water temperature instrumentation has been installed for normal operation with non-1E power because it will not be required during or after an accident.

l The previous design consisted of local sensors at Elevation (El)95' MSL.

l The present TS's require verifying each 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> that the water temperature is less than or equal to 82*F and include additional measures to verify temperature every 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> when the previous reading was greater than or equal to 75'F or every 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> when it was greater than or equal to 80*F.

l The design as installed consists of four wide range (0-100*F) sensors at '

approximate El. 110' and 65' and eight narrow range (75 to 85'F) sensors at approximate E1. 111', 102', 87' and 72'. The sensors feed a processor which averages the input, provides local wide and narrow range indication, control room wide and narrow range indication and a Main Control Room alarm. The processor has an installed backup which can be i replaced by a standard personal computer. Since the new system provides l indication and an alarm in the Main Control Room, the previous requirements to increase surveillance frequency when the temperature exceeds 75*F will not be necessary when the Control Room instrumentation is operable.

The note added to TS 4.7.1.2.b provides a minimum number of sensors and elevations to establish a representative average water temperature. The use of at least four sensors with at least half above El, 94' HSL (grade) is believed to be conservative because under the normal standby (passive) conditions the only heat source would be above grade through solar heat. Approximately two-thirds of Basin Volume will be a " heat sink" transferring heat below grade. Four sensors wil] also conservatively indicate the UHS vater temperature under normal conditions because with at least half of the sensors in the warmer one-third of the UHS, the true average temperature will be cooler than measured and therefore, conservative.

NO SIGNIFICANT HAZARDS CONSIDERATION:

As discussed in 10CFR50.92, the following discussions are provided to the NRC Staff in support of "no significant hazards considerations".

1. No significant increase in the probability or the consequences of an accident previously evaluated results from this change because:

The UHS basin water temperature is monitored to assure the plant is within the bounds of the initial conditions assumed in the Safety Analysis and has no post accident functions. This does not change any previous safety analysis. The previous surveillance intervals when the temperature exceeds 75'F were to assure operator awareness and to maintain the plant within the inital conditions of the SAR.

The Control Room indication and alarm functions replace the previous manual actions and are supplemented by the increased surveillance l

when the instrumentation is unavailable. The addition of the minimum equipment to implement the surveillance is to assure a representative indication of basin temperature to confirm the basin temperature is within the initial conditions of the Safety Analysis.

Since the system has been previously found to support Safety Analysis and the present Limiting Conditions for Operation (LCO) will continue without change, no increase in the probability or consequences of an accident previously evaluated results from this change.

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2. This change would not create the possibility of a new or different j kind of accident from any' accident previously evaluated because:

The system -has been found to support the' functions assumed in the l

.SAR and the use is functionally identical to the original' design with the enhancements of remote indications:and an alarm. A review of-Regulatory Guide l.47, NUREG-0800 and other available information.

found no specific requirements for UHS temperature monitoring.

Since the monitoring of the temperature exceeds ~the guidance and the proposed, surveillance establishes additional assurance, the plant' will respond as described in the SAR.- - In addition, the' LCO and Actions required by the TS are' unchanged. .Thereby maintaining'the UHS operation and performance within all accident conditions previously evaluated.

3. This change.would not involve a significant reduction in the margin  !

of safety because:

The UHS temperature is maintained within the present safety analysis by. the'.new system and the specific requirement of monitoring the heat sink temperature will be maintained by the once per 24 hour2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br /> surveillance. requirements. . The temperature. received by the operators will conservatively' reflect the actual water temperature.

'The configuration of: the sensors even when'at the minimum number will indicate a temperature which :is above the true average.

Therefore, the design and surveillance requirements are conservative with. respect to the safety analysis. In addition, this change does not reduce the margin of safety identified in the Bases in the River Bend Technical Specifications.

The proposed amendment, as discussed above, has not changed the system design, function and operation contained in the SAR and therefore, will not increase' the probability or the consequences. of a previously evaluated event or will not create a new or different event. Since the ability to perform, as described in the SAR, is maintained- by this change, the proposed changes do not result in a significant reduction in the margin of safety. GSU proposes that' no significant hazards are involved.

REVISED TECHNICAL SPECIFICATION As- indicated above, River Bend Station is currently in compliance with the applicable Technical Specification. The proposed changes are provided in the Enclosure.

SpHEDULE TO ATTAIN COMPLIANCE As discussed above, the proposed revision maintains Limiting Conditions for Operation and Action requirements presently in place. The change reduces the manual surveillance requirements when the temperature exceeds 75'F and provides increased information to calculate the average temperature, Therefore, operation with the present TS's is conservative for the interim period. This position is supported during the winter i i

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l which tends to depress the basin temperature, thereby enhancing UHS performance. GSU proposes that since proposed revision is to increase the level of safety, that continued operation be permitted under the present Technical Specifications and requests this change be approved during the first quarter 1988.

I NOTIFICATION OF STATE PERSONNEL i

A copy of the amendment application and this submittal has been provided to the State of Louisiana, Department of Environmental Quality-Nuclear Energy Division.

ENVIRONMENTAL IMPACT APPRAISAL Revision of the Technical Specification does not result in an environmental impact beyond that previously analyzed. Therefore, an approval of this amendment does not result in a significant environment impact nor does it change any previous environmental impact statements '

for River Bend Station.

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ENCLOSURE i I

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