ML20097D916

Suppl to 910424 Application for Amends to Licenses NPF-11 & NPF-18,proposing Deletion of Requirement for SDV & Drain Valve Surveillance to Be Performed from Normal Control Rod Configuration of Less than or Equal to 50% Rod Density

ML20097D916
Person / Time
Site:	LaSalle
Issue date:	06/02/1992
From:	Shields J COMMONWEALTH EDISON CO.
To:	Murley T NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM), Office of Nuclear Reactor Regulation
Shared Package
ML20097D918	List: ML20097D916 ML20097D927
References
NUDOCS 9206110201
Download: ML20097D916 (6)

Text

_

N Common alth Edison i [ ) 1400 opus Placa s Down:ts orov3, Illinois 00315 June 2,1992 Dr. Thomas E. Murley, Director Office of Nuclear Reactor Regulation Ahn: Document Control Desk U.S. Nuclear Regulatory Commission Washington, D.C. 20555

Subject:

LaSalle County Station Units 1 and 2 Supplement to the Proposed Amendment to Facility Operating Licenses NPF 11 and NPF 18 Appendix A, Technical Specifications NRC Docket Nos. 50 373 and 50 374 Scrant Dis ch ar geNotume_and.conkoLBod_Oprability_

References:

(a) P.L. Piet letter to USNRC, dated Apd> i991, Application for Amendment to Facility Operating Licenses NPF 11 and NPF 18, Appendix A, Technical Specifications, Scram Discharge Volume and Control Rod Operability (b) P.L. Piet letter to USNRC, dated A3ril 02,1991, Application for Amendment to Faci lity Operating Licenses NPF 11 and NPF-18, Appendix A, Technical Specifications, Deletion of Rod Sequence Control System and Lowering of Rod Worth Minimi:cr Setpoint Reference (a) submitted Commonwealth Edison's (CECO) request for an amendment to Facility Operating Licenses NPF 11 and NPF-18, Appendix A, Technical Specifications. The purmse of this amendment request was to provido allowable outage times (AOT) for 1he Scram Discharge Volume (SDV) Vent and Drain Valves, and to remove from the Control Rod Operability Technical Specifications the Unit 1 and Unit 2 SDV Surveillance Requirements for SDV Level Instrumentation.

This letter supplements the original amendment request and proposes to delete the requirement for the SDV Vent and Drain Valve surveillance to be performed from a normal control rod configuration of less than or er4ual to 50% rod density. It is requested that the amendments be made effective 45 days from the date of approval to allow time for any required procedural revisions to be completed.

in Reference (b), an amendment to the Rod Worth Minimizer and Rod Sequence Control System was proposed, and rec uested changes to page 3/41-4 of both Facility 4 Operating Licennes NPF 11 and NPF08. Note that this page is also included in the i present proposed amendment. Please ensure that the most current version of this page is included in the approved version of each amendment.

K0045

,d~( 3 E8P'A888A o88M!n P PDR l-ZNLD/1847/1 c

t Dr. Thomas Murley 2- June 2,1992 The proposed supplement to the amendment request is subdivided as follows: .1

1. Attachment A gives a description and evaluation of the proposed changes.

2. Attachment B includes the marked up Technical Specification pages, including the original and supplemental changes.

3. Attachment C describes CECO's evaluation performed in accordance with 10 CFR50.92 (c), which confirms that no significant hazards consideration is involved.

4. Attachment D provides the Environmental Assessment.

5. Attachment E provides additional support material which will aide in the review of th proposed amendment request.

This proposed s CECO On Site and fto_upplemental Site Review in amendment accordance with hasCommonwealth been reviewedEdison and approved by procedures.

Commonwealth Edison is notifying the State of Illinois of this apatication for amendment by transmitting a copy of ti l ls letter and its attachments Lo the designated state official.

To the best of my knowledge and belief, the statements contained within are true and correct. In some resoect these statements are not based on my aersonal knowledge, but obtained Information furnished by other Commonwea th Edison em aloyees, contractor employees, and consultants. Such Information has been

) rev ewed in accordance w th company practice, and I believe it to be reliable.

Please direct any questions you may have concerning this submittal to this office.

Respectfully, v u e et_ county ot/

p n tN day

' bjfore 18 - Y- ~

Jo nn M. Shields ff ary PubHc y, Nuclear Licenong Administrator

.g .

,~~ w ::::::.:::::::: m

" OFFICI AL SE AL " l!

S AfJDR A C. LAR A h MTARY PUSUC. STATE OF ILUN0!S MY COYVISSION EXPlRES 0/2b/M

... ~ m m

'ZNLD/1847/2

Dr. Thomas Murley , --3-- June 2,1992.

Attachments:

-A. Description and Evaluation of the Proposed Changes -

B.- . Marked Up Technical Specification Pages =

0. Evalue, tion of Significant Hazards Consideration D. Environmental Assessment-E.. . Addtkinal Support Information cc: A.B. Davb,' Regional Administrator - Rill D.L.- Hills, Senior Resident inspector LSCS B.L. Siegel, Project Manager - NRR ,,

Office of Nuclear Facility Safety -IDNS l Subscribed and Sworn before me lhls ' day of . .%2 Notary Public c-' -

_j a

4

-i

a

+

',t_.

I +

ZNLD/1847/3 -.

> t;s- -

n-h : - .. . - .. -- .. , ,

_ . , . . m,..,j__._m__., _ _m _ m ...m .

ATTACHMENT A Description and Evaluation of Proposed Change to Appendix A, Technical Specifications cf Facility Operating Licenses NPF 11 and NPF 18 Description.pttbefroposecLCoange This supplement to the original amendment request proposes an additional change to the Technical Specifications concerning the Scram Discharge Volume (SDV) vont and drain valves. The current Technical Specifications require that the SDV vent and drain valves be verified operable when control rods are scram tested from a normal control rod configuration of less than m equal to 50% rod density. This amendment rec uest deletes the requirement for this surveillance to be performed with control rods ,

wit idrawn to prevent an unnecessary plant transient and an unnecessary challenge of plant safety systems.

The Reference (a) submittal contained the discussion of the addition of Techr.ical Sr* i a ations 3.1.3.1.d and 3.1.3.1.e, and the deletion of Surveillance Requirement 4 t 11 b.

D#wiption oLCuttenLBequkement The Technical Specification Surveillance Requirement 4.1.3.1.4 currently states:

, "The scram ischarge volume shall be determined OPERABLE by demonstrating:

a. the scram discharge volume drain and vent valves OPERABLE, when control rods are scram tested from a normal control rod configuration of less than or equal to 50% ROD DENSITY at least once per 18 months

• by verifying that the drain and vent valves:

1. Close within 30 seconds after receipt of a signal for control rods to scram, and

2. Open after the scram signal is reset.

• The provisions of Specification 4.0.4 are not app!icable for entry into OPERATIONAL CONDITION 2 provided the surveillance is performed within 12 hours1.388889e-4 days <br />0.00333 hours <br />1.984127e-5 weeks <br />4.566e-6 months <br /> after achieving less than or equal to 50% ROD DENSITY."

The scram discharge volume is sized to contain all of the water discharged by the control rod drives during a acram. Under normal plant conditions, the scram discharge volume is empty, and the it and drain valves are open. (A simplified drawing is Upon a scram signal, the vent and drain valves close to included maintain water in Attachment inventory. E.)After the' scram signalis cleared, the scram discharge volume logic is manually overridden, the vent and drain valves open, and the scram discharge volume drains again. The appropriate pages from the UFSAR which describe the system as discusued in this supplement, as well as those that describe the system affected_in the original submittal, are included in Attachment E to this supplement.

ZNLD/1847/4

r w

Dates for the._01Irent Requkement The scram discharge volume valves need to be operable during normal operation to ensure that sufficient volume is available to accept water in the event of a scram.

The valves need to be operable during a reactor scram to effectively isolate the reactor coolant system hom the environment.

The vent and drain valve operability is determined by means of a scram test from a normal control rod density of less than or equal to 50% control rod density. This rod configuration requires the reactor to be in Operational Condition 1, Power Operation, or Operational Condition 2, Startup, when the surveillance is performed.

D.eacdpiloaotthelleed_toramending_the.IechnLcalSpecification The current surveillance scram is performed solely to verify operability of the scram discharge volume vent and drain valves, and as such, cannot be performed in conjunction with other required tests.

This requirement causes an unnecessary plant transient every 18 months, and needlessly challenges plant safety systems. This proposed amendment would allow- >

for plant shutdowns to be performed in a controlled fashion to m31mize major transients. Based on the current forty year operating license, this amendment request would eliminate approximately 26 scrams per unit and the accompanying safety system challenges.

If maintenance is performed on the SDV vent or crain valves, the currently required startup/ shutdown cycle can be avoided by the proposed amendment by being able to test these valves during shutdown conditions. The proposed amendment will therefore also reduce the financial burden to CECO from extra plant shutdowns.

ResctiptionoithelmendedlechnicaLSpecificatio1Bequirement LaSalle County Station pro mses that the Technical Specification Surveillance requirement be amended as foi ows:

"The scram discharge volume shall be determined OPERABLE by demonstrating the scram discharge volume drain and vent valves OPERABLE at least once per 18 months by verifying that the drain and vent valves:

a. Close within 30 seconds after receipt of a signal for control rods to scram, and

b. Open after the scram signal is reset."

This proposed change would eliminate the need for Note

• at the botto.o of page 3/41-5, which gives exception from Specification 4.0.4, since there would be no requirement to change modes to perform the surveillance.

ZNLD/1847/5

1 A marked up version of the current requirement Indicating the requestod wanges is included in Attachment B .

BasesJottbeAmended.IechnicaLSpecification. Bequest The operability of the SDV vent and drain valves can be satisfactorily demonstrated during an actual or simulated scram from shutdown conditions. Reactor pressure and CRD discharge flow conditions do not affect the SDV vent and drain valve closure rates, because the SDV has adequate volume and is initially vented so that peak pressure prior to SDV isolation will not be significant to the closure rates. The ability of the valves to open after a scram at lens than er equal to 50% rod density could be affected by this proposed amendmoni, since a 50% rod density backpressure would be equivalent to operating reactor pressure, while backpressure would not be significant durin0 testing at shutdown conditions. However, the ability of the valves to open against rated reactor pressure is demonstrated after each reactor scram during unit operation.

Procedures were pedormed at LaSalle County Station which demonstrated that there is less than or equal to 1 second difference in closing time for each SDV valve from a scram from less than or equal to 50% rod density versus the closure time from either the SDV vent and drain valve test buttons or from a cold shutdown scram with all control rods full in.

The proposed change would still ensure that the Scram Discharge Volume would be isolable, and that the Control Rod Drive system would still be able to effect a safe shutdown, as discussed in the Standard Review Plan, NUREG-0800, Section 4.6, Functional Design of Control Rod Drive System, Tht. Scram Discharge Volume vent and drain valves are not specifically addressed in the Safety Evaluation Roport, NUREG-0519, Section 4.6.2, Control Rod System. e The redundant valves at discussed in the March 1981 issue of NUREG-0519 were p[eviously installed as required.

This proposed amendment uses wording for the surveillance requirement which is similar to that of Clinton, Perry, and River Bend Stations. Copies of the appropriate portions of these documents are included in Attachment E.

In conclusion, it is requested that this supplement to the amendment be approved, It is further requested that the amendments be made effective 45 days from the date of approval to allow time for any required procedural revisions to be completed.

ZNLD/1847/6

_ _ _ _ _