ML20094J648

Application to Amend License NPF-18,changing Tech Specs Re Reactor Scram on Low CRD Pump Discharge Pressure Mod. Requests for Emergency Amend, & 0801,unwarranted in That Derating or Shutdown Not Imminent

ML20094J648
Person / Time
Site:	LaSalle
Issue date:	08/02/1984
From:	Rybak B COMMONWEALTH EDISON CO.
To:	Harold Denton Office of Nuclear Reactor Regulation
References
9025N, NUDOCS 8408140405
Download: ML20094J648 (3)

Text

._

. . ['N Commonwealth Edison 1 ,

[ } one First National F'faza, Chicigo, Illinois

( C ] Address Reply to: Post Office Box 767

( ,,/ Chicago, Illinois 60690 August 2, 1984 Mr. Harold R. Denton, Director Office of Nuclear Reactor Regulation U.S. Nuclear Regulatory Commission Washington, DC 20555

Subject:

LaSalle County Station Unit 2 i Request for Exigent Amendment to Technical Specification for Facility Operating = License NPF-18 Reactor Scram on Low Control Rod Drive (CRD)

Pump Discharge Pressure Modification NRC Docket No. 50-374 References (a): B. Rybak letter to H. R. Denton dated July 31, 1984.

(b): 8. Rybak letter to H. R. Denton dated August 1, 1984.

Dear Mr. Denton:

Per the referenced letters Commonwealth Edison submitted an cmergency amendment to Facility Operating License NPF-18 which first requested a relaxation from the requirements of Amendment No. 3 and then a vacation of the Amendment. These requests were made due to spurious scrams found during testing of the modification on July 30. These requests for an emergency amendment were credicated on our belief that a high probability exists that Unit 2 could not be returned to service due to these spurious scrams. LaSalle was'able to return to service today without scramming. Therefore, our request for an emergency amendment request, pursuant to 10 CFR 50.91.5 is no longer warranted in that a deratin0 or shutdown of LaSalle County Unit 2 is not imminent. However, we still believe that, were Unit 2 to shutdown again, the Unit would be at least hindered and more likely prevented from returning to service due to spurioue ono unnecessary scrams resulting from this modification.

Accordingly, we request that our application for an emergency amendment to vacate Amendment No. 3 be changed to an exigent consideration.

o\

o 8408140405 840002 PDR ADOCM 05000374 l

(t 9 P PDR

y o o'

H. R. Denton August 2, 1984 We feel our original request meet the requirements of 10 CFR 50.91 for an emergency application. The original License Condition 2.7(C) required the modification to be operable by completion of the plant startup testing. The expected completion of all startup testing will be by October, 1984. Work was underway to complete this modification at the time of the Amendment's approval.

On July 30 the modification was in its final stages of testing when the problem of spurious scrams was discovered. That information coupled with the fact that the unit was shutdown created a emergency situation which we could not avoid. Our application for emergency relief was made on July 31. Our investigations to date suggest that the probable cause of the problem to be the conservative setpoints may not have sufficient margin against the current discharge pressure of the CRD pumps. Additional analysis is necessary to determine a proper setpoint which would both avoid unnecessary scrams and fulfill the intended safety function of this modification. That analysis has started and will be completed as soon as possible. A revised Technical Specification amendment will promptly be submitted.

Given the time needed to confirm the cause of the problem and likelihood of altering the scram setpoint we request that the NRC proceed to vacate Amendment No. 3 in an exigent manner. Were Unit 2 to incur a shutdown in the immediate future the requirements of 10 CFR 50.91 for an emergency amendment request would still be met. There are no actions that can be taken by the Licensee to avoid this situation if this request is not approved. Therefore prudence suggests that to avoid another emergency request an exigent review and approval by the NRC is appropriate.

Our review of this request to vacate Amendment No. 3 has determined that no significant hazards consideration exists. Vacation of Amendment No. 3 will reinstate License Condition 2.7(C) which required this modification to be done prior to the end of the startup testing. We will meet this License Condition by having the modification operational by that pe11od. It is implicit that no significant hazards existed if the licensee did not complete this work until the end of startup testing, otherwise the NRC would not have allowed any period of operation without the modification functional. Furthermore, no significant hazards consideration exists when measured against the standard of 10 CFR 50.92.C. Vacation of the amendment is only temporary; the modification will be operational prior to the completion of the Unit startup testing.

Therefore, no significant reduction in safety will exist during the period when the amendnient is vacated and the modification made operational with the proper setpoint.

7,.

[ * '

~

s

. H. R. Denton- -

August 2, 1984

. . . Please direct any questions'you may have concerning this matter

-ito this: office.

~

0ne_ signed originals and forty (40) copies of this transmittal are.provided_for your use.

Very-truly yours, B. Ry

. Nuclear Lice g Administrator

- lm

. cc: Region III Inspector - LaSalle

- A. Bournia - NRR G. Wright - Ill.

9025N 1