ML20141J552

Application for Amends to Licenses NPF-11 & NPF-18,proposing Deletion of Surveillance Requirement 4.7.1.3.c & Addressing Sedimentation Concerns in Intake Structure Under Svc Water Performance Monitoring Program,Iaw GL 89-13

ML20141J552
Person / Time
Site:	LaSalle
Issue date:	08/12/1997
From:	Subalusky W COMMONWEALTH EDISON CO.
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
Shared Package
ML20141J558	List: ML20141J552 ML20141J567
References
GL-89-13, NUDOCS 9708200098
Download: ML20141J552 (10)

Text

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conm,onweanh ninon company IAalle Generating Ntion

. 2(dll NYthylst No.ul Wrdlw IL M 3 i1-975?

rei ais m<,7<,i August 12,1997 United States Nuclear Regulatory Commission Attention: Document Control Desk Washington, D.C. 20555

Subject:

LaSalle County Nuclear Power Station Units 1 and 2 Application for Amendment of Facility Operating {

Licenses NPF-11 and NPF-18, Appendix A, Technical

- Specifications, to change the surveillance requirements for the ultimate heat sink by deletion of the sediment deposition inspection in the lake screen house.

NRC Docket Nos. 50 373 and 50-374 Pursuant to 10 CFR 50.90, Commonwealth Edison Company (Comed) ,

- proposes to revise Appendix A, Technical Specifications of Facility Operating  !

Licenses NPF-11 and NPF-18, LaSalle County Station Units 1 and 2.

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--Technical Specification (TS) Surveillance Requirement (SR) 4.7.1.3.c requires that every 18 months all areas within the lake screenhouse behind the bargrill be inspected to ensure that sediment has not been deposited to a depth greater than 12 inches. LaSalle proposes to delete SR 4.7.1.3.c from LaSalle Unit 1 and Unit 2 Technical Specifications and control the accumulation cf sediment in the lake screenhouse under the Service Water Pedormance Monitoring Program. The surveillance requirement is not a part of Standard TS and the Service Water Performance Monitoring Program is more suited for this type of inspection / work. This program is in accordance with Generic Letter 89-13.

This proposed amendment request includes the following:

1. Attachment A gives a description and safety analysis of the proposed changes in this amendment.

2. Attachment B includes the marked-up License / Technical Specifications pages for LaSalle Units 1 and 2 with the requested I changes indicated, de 9708200098 970812 7 +1 .,

PDR ADOCK 05000373 P PDR ,

islaspittiEt

3. Attachment C describes Comed's evaluation performed in accordance with 10 CFR 50.92 (c), which confirms that no significant hazard consideration is involved.

4. Attachment D provides an Environmental Assessment Applicability Review per 10 CFR 51.21.

This proposed amendment has been reviewed and approved by Comed Onsite and Offsite Review in accordance with procedures.

Comed requests approval of this amendment request prior to Unit 1 Start-up from the current outage L1F35 which is currently scheduled for December 15,1997. The amendments will be implemented upon startup of A Units 1 and 2 from the current outages.

Comed is notifying the State of Illinois of this application for amendment by transmitting a copy of this letter and its attachments to the designated state official.

If there are any further questions or comments concerning this submittal, please refer them to Perry Bames, Regulatory Assurance Supervisor, at (815) 357-6761, extension 2383.

Respectfully, 9

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W. T. Subalusky Site Vice President LaSalle County Station Enclosure cc: A. B. Beach - Regional Region ill Administrator M. P. Huber, NRC Senior Resident inspector - LaSalle D. M. Skay - Project Manager - NRR - LaSalle F. Niziolek, Office of Nuclear Facility Safety -IDNS DCD - Licensing (Hardcopy: Electronic: )

Central File I

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STATE OF ILLINOIS )

)

COUNTY OF LASALLE )

IN THE MATTER OF )

) Docket Nos. 50 373 COMMONWEALTH EDISON COMPANY ) 50-374

)

LASALLE COUNTY UNITS 1 & 2 )

AFFIDAVIT I affirm that the content of this transmittai is true and correct to the best of my knowledge, information and belief.

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s ( j [hC^ vA WRha'm T. Subalusky h Site Vice President LaSalle County Station Subscribed and sworn to before ' ie, a Notary Public In gnd for the,@t . 9 of Illinois, thiu /A' day of f, 19_ 99. My Commission e@xpires on Io - I 1VJD.*O

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NOTARY PUIVLIC 4 OffcAL SEAL

}' OtBRAJ.FEENEY NOTARf PUBLIC. STATE OFILLINDIS

• W COMMISSIDN EXPIRES 1012000

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ATTACHMENT A 1 DESCRIPTION AND SAFETY ANALYSIS OF THE PROPOSED CHANGES l -

! Description of the Proposed Change i

Commonwealth Edison Company (Comed), LaSalle County Station (LaSalle) Unit 1 and Unit 2 Technical Specification (TS) Surveillance Requirement (SR) 4.7.1.3.c ,

requ!res that every 10 months all areas within the lake screenhouse behind the '

i bargrill be inspected to ensure that sediment has not been deposited to a depth

greater than 12 inches. LaSalle proposes to delete SR 4.7.1.3.c from LaSalle

, Unit 1 and Unit 2 Technical Specifications and control the accumulation of sediment in the lake screenhouse under the Service Water Performance i Monitoring Program. The surveillance requirement is not a part of Standard TS l and the Service Water Pe:Tormance Monitoring Program is more suited for th!s -

type of inspection / work. This program is in accordance with Gensric Letter j 89 13.

! Description of the Current Operatina License / Technical Specification Reaulroment -

To ensure that the Core Standby Cooling System (CSCS) pond continues to i meet the guidelines of Regulatory Guide 1.27 and the positions of Branch Technical Position ASB 9 2, the Nuclear Regulatory Commission incorporated '

SR 4.7.1.3.a and b into LaSalle's Technical Specifications. SR 4.7.1.3.c was ,

added to assure sediment from the lake would not block the inlets to the CSCS cooling water screen bypass supply line and normal tunnel supply lines.

4.7.1.3 requires that the CSCS pond shall be determined OPERABLE at least once per 18 months by determining that:

a. No sediment deposition in excess of 1.5 feet has occurred in the intake fiume or in the CSCS pond as determined by a series of sounding cross- 4 sections compared to as built soundings.

b. The pond bottom elevation is less than or equal to 686.5 feet.

c. Sediment deposition anywhere within the lake screenhouse behind the bargrill is not greater than one foot in thickness.

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ATTACHMENT A  !

DESCRIPTION AND SAFETY ANALYSIS OF THE PROPOSED CHANGES I

Bases for the Current Reaulroment From Bases Section: ~

3/4.7.1 Core Standby Cooling System Equipment Cooling Water Systems.

"The OPERABILITY of the core standby cooling system equipment cooling water systems and the ultimate heat sink ensure that sufficient cooling capacity is available for continued operation of safety related equipment during normal and accident conditions. The redundant cooling capacity of these systems, assuming a single failure, is consistent with the assumptions used in the accident conditions within acceptable limits."

From UFSAR Section 9.2.6.1.1:

"The ultimate heat sink has the following design bases:

a. "To provide sufficient water volume permitting a safe shutdown and cooldown of the station for 30 days with no water makeup for both normal operating and accident conditions - the maximum -

permissible water temperature supplied to the plant is taken as 1 100 'F; l

b. To withstand thIe most severe postulated natural phenomenon as discussed in Chapter 2.0;

c. "To withstand the postulated site related incidents as discussed in Subsection 2.5.5; and

d. "To provide water for fire protection equipment."

The natural phenomena referenced in item b above, are occurrences relating to floods,. earthquakes, storms, lightning, tornados and other natural disasters.

The site related incidents in item c above relate to damage to the ultimate heat sink and lake due to cave ins, faults, washouts, soil and rock movement.

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ATTACHMENT A DESCRIPTION AND SAFETY ANALYSIS OF THE PROPOSED CHANGES NUREG 0519 Supplement 2, Safety Evaluation Report Related to the Operation of LaSalle County Station Units 1 and 2, section 9.2.2 provides the basis related

. to TS SR 4.7.1.3.s through c:

"In order to assure against excessive sedimentation in the ultimate heat sink and lake screenhouse, a surveillance requirement will be included in the Technical Specifications to assure that sedimentation thickness does not exceed the allowable limits of 1 1/2 feet in the pond and 1 foot in the lake screenhouse. The latter would assure that any sediment buildup in 3 the lake screenhouse would be below the bottom of the core standby cooling system inlet pipe. Therefore, we conclude that this revision is acceptable to us, and we will incorporate the surveillance requirements into the Technical Specifications."

The intake fiume portion of the CSCS pond is concrete just before the lake screenhouse, so that there is a smooth bottom transition between the CSCS pond and the circulating pump suction bays in the lake screenhouse behind the bergrill. Due to this design,18 inches of sediment in the CSCS pond was a concern in that the layer of sediment could extend into the circulating pump suction bays and thus up to the inlets to the service water tunnel. The bottom of the inlets were 18 inches above the bottom of the circulating water pump suction bays, so 18 inches of sediment would cause the sediment to be at the

. bottom of the piping inlets. A concern that sediment may begin to block or foul the piping resulted in surveillance acceptance criteria set at 12 inches to provide margin.

l' Dancription of the Need for Amending the Operating License / Technical Specifica.tl9n TS SR 4.7.1.3.c acceptance criteria was not written to address sediment .

accumulation in either the CSCS cooling water screen bypass supply line or the service water tunnel, but litatead to assure no blockag6 of flow or fouling of the CSCS screen bypass line. - Also, a review of the design basis for the Ultimate Heat Sink has determined that TS SR 4.7.1.3.c is not directly associated w!!h proving the operability of the Ultimate Heat Sink. However, TS SR 4.7.1.3.c states that the sediment deposition is to be checked to be less than 12 inches A-3

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ATTACHMENT A DESCRIPTION AND SAFETY ANALYSIS OF THE PROPOSED CHANGES "anywhers in the lake screenhouse", which includes the CSCS cooling water screen bypass supply line and the service water tunnel (See Figure 1, LaSalle Lake Screen House).

The sediment does not collect such that it blocks or causes potential for fouling cf the CSCS piping inlets to the service water tunnel or the suctions for the CSCS Essential Service Water System (ECWS) pumps from the service water tunnel.

l However, the rectangular shape of the circulating water pump suction bays and the service water tunnel and the normally isolated CSCS cooling water screen bypass supply line create low flow and/or no flow areas. Therefore, material carried by the water flow into the circulating water pump suction bays and the service water tunnel settles out and collects to depths greater than 12 inches between survelliances in some areas.

LaSalle proposes to delete SR 4.7.1.3.c from LaSalle Unit i and Unit 2 Technical Specifications and control the Inspections for sediment accumulation and the removal of sediment in the lake screenhouse under the Service Water Performance Monitoring Program, in accordance with Generic Letter 8913. The program will assure continued operability of CSCS ECWS through performance monitoring of heat exchangers and components as well as through the sediment surveillances in the lake screenhouse.

Description of the Amended Operating License / Technical Specification Reauirement This amendment involves removing SR 4.7.1.3.c from TS and addressing sedimentation concerns in the intake structure under the Service Water Performance Monitoring Program. Inspection, evaluation, and cleaning of the intake structure for sediment and fouling is specifically addressed in the recommended actions of GL 8913. The Service Water Performance Monitoring Program meets recommended actions of GL 8913.

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i ATTACHMENT A DESCRIPTION AND SAFETY ANALYSIS OF THE I PROPOSED CHANGES 4

Bases for the Amended Operating License / Technical Soesification Reqqtal j

l Reviews of original Standard Technical Specifications, such as NUREG 0123,

' Standard Technical Specifications for General Electric Bolling Water Reactors (BWRl5); new Standard Technical Specifications, such as NUREGs 1433 and 1434; Technical Specifications for all other Comed Nuclear Power stations; andTechnical Specifications for many other nuclear stations, have found no l other stations with TS SRs for sedimen2ation in intake structures, nor any i reason for inclusion of such surveillances, i

At no time, during approximately fourteen years of LaSalle operation, has

. sediment built up or accumulated either in front of the inlet to the CSCS cooling

! water screen bypass supply line or the six 36-inch normal tunnel supply lines in

- such a manner that the flow of water through these lines could have been l reduced or blocked, instead, loose sediment collects in quiescent areas near l the traveling screens, the north end of the Service Water Tunnel, under the

! outlets of the 36-inch normal tunnel supply lines in the service water tunnel, and l j downstream of the butterfly isolation valve in the 54 inch CSCS cooling water  ;

screen bypass supply line. The sediment that collects in the service water '

tunnel does not build up in a manner such that CSCS-ECWS, non essential ,

l station service water, or fire pump suctions from the tunnel are affected, based on inspections since 1992.

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[ The CSCS equipment cooling bypass valve,0E12-F300, is the manual butterfly '

valve in the CSCS cooling water screen bypass supply line. The bypass valve is

, being added to the ASME Section XI Inservice Testing Program to cycle the valve quarterly. This valve cycling will help maintain sediment level in the i bypass line at a low level due to flow through the line while the valve is not fully .

! closed and thus assure the bypass line remains available. The flow is created due to the differential pressure across the circulating water traveling screens

with circulating water pumps in operation. '

Also, since implementation of the recommendations of Generic Letter !!9-13 in  !

_1990, performance monitoring, inspections and tests have been performed to j trend heat exchanger and system performance to assure continued operability, i

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i ATTACHMENT A DESCRIPTION AND SAFETY ANALYSIS OF THE PROPOSED CHANGES The control of sedimentation in the intake structure is included in the LaSalle LTP 300 34, Service Water Performance Monitoring Program, which is in compliance with recommended action A of NRC Generic Letter 8913 " Service Water System Problems Affecting Safety Related Equipment"(GL 8913). This program maintains the same or higher level of safety as the current surveillance requirement to assure that the Core Standby Cooling System Equipment Cooling Water Systems (CSCS ECWS) and fire suppression water system requirements have flow paths capable of taking suction from the service water tunnel and Ultimate Heat sink under analyzed conditions.

Therefore TS SR 4.7.1.3.c is not required and may be deleted from the LaSalle

. TS.

Sched_y.la i Comed requests approval of this amendment request prior to Unit 1 Start up from the current outage L1F35 which is currently scheduled for December 15, 1997. The amendments will be implemented upon startup of Units 1 and 2 from the current outages. >

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CSCS COOLING WATER SCREEN BYPASS MANUAL BUTTERFLY VALVE NORMALLY LOCKED CLOSED

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