ML17285A956

Application for Amend to License NPF-21,revising Tech Spec 3/4.4.2, Safety/Relief Valves, Reducing Required Number of Operable Safety Relief Valves from 12 to 4 When Power Less than 25% of Rated Thermal Power

ML17285A956
Person / Time
Site:	Columbia
Issue date:	01/09/1990
From:	Sorensen G WASHINGTON PUBLIC POWER SUPPLY SYSTEM
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
Shared Package
ML17285A957	List: ML17285A956 ML17285A958
References
GO2-90-006, GO2-90-6, NUDOCS 9001190106
Download: ML17285A956 (10)

Text

, ACCELERATED UTION DEMON TION SYSIHM

.j REGULATORY INFORMATION DISTRIBUTION SYSTEM (RIDS)

ACCESSION NBR:9001190106 DOC.DATE: 90/01/09 NOTARIZED: YES DOCKET FACIL:50-397 WPPSS Nuclear Project, Unit 2, Washington Public Powe 05000397 AUTH. NAME AUTHOR AFFILIATION SORENSEN,G.C. Washington Public Power Supply System RECIP.NAME RECIPIENT AFFILIATION Document Control Branch (Document Control Desk)

SUBJECT:

Application for amend to License NPF-21,revising Tech Spec 3/4.4.2, "Safety/Relief Valves."

DISTRIBUTION CODE: A001D COPIES RECEIVED LTR ENCL SIZE- D TITLE: OR Submittal: General Distribution NOTES

/

RECIPIENT COPIES RECIPIENT COPIES ID CODE/NAME LTTR ENCL ID CODE/NAME LTTR ENCL A PD5 LA 1 1 PD5 PD 1 1 SAMWORTH,R 5 5 D INTERNAL: ACRS 6 6 NRR/DET/ECMB 9H 1 1 NRR/DOEA/OTS B11 .1 1 NRR/DST 8E2 1 1 NRR/DST/SELB 8D 1 1 NRR/DST/SICB 7E 1 1 NRR/DST/SRXB 8E 1 1 NUDOCS-ABSTRACT 1 1 OC 1 0 OGC/HDS2 1 0 REG FI 01 1 1 RES/DSIR/EIB 1 1 EXTERNAL: LPDR 1 1 NRC PDR 1 1 S'R NSIC 1 1 D

A NOTE TO ALL "RIDS" RECIPIENTS:

PLEASE HELP US TO REDUCE WAS'! CONTACT THE. DOCUMENT CONTROL DESK, ROOM Pl-37 (EXT. 20079) TO ELIMINATEYOUR NAME FROM DISTRIBUTION LISIS FOR DOCUMENTS YOU DON'T NEED!

TOTAL NUMBER OF COPIES REQUIRED: LTTR 27 ENCL, 25,.

0 9

I I

"l 4

,1

WASHINGTON PUBLIC POWER SUPPLY SYSTEM P.O. Box 968 ~ 3000 George Washington Way ~ Richland, Washington 99352 January 9, 1990 G02-90-006 Docket No. 50-397 U. S. Nuclear Regulatory Commission Attn: Document Control Desk Washington, D.C. 20555 Gentlemen:

Subject:

NUCLEAR PLANT NO. 2, OPERATING LICENSE NPF-21 RE(VEST FOR AMENDMENT TO TECHNICAL SPECIFICATION 3/4.4.2 SAFETY/RELIEF VALVES In accordance with the Code of Federal Regulations, Title 10, Parts 50.90 and

2. 101, the Supply System hereby submits a request for amendment to the WNP-2 Technical Specifications. Specifically, the Supply System is requesting that the required number of operable safety relief valves (SRV) be reduced from 12 to 4 when thermal power is less than 25% of RATED THERMAL POWER (See Attachment 1),

This request is made to provide more flexibility in outage scheduling and maintaining an adequate number of safety relief valves operable during outages and subsequent restarts. Attachment 1 also includes appropriate changes to the Bases.

Presently because the Supply System has no test facility for SRV testing, all SRV testing to prove operability is done in-situ. The plant is at power when the operability of a refurbished valve is confirmed by test. All valves removed for maintenance are considered inoperable prior to the in place test. A valve is declared operable upon satisfactory completion of the in place test. With the present technical specifications requiring 12 operable valves only 6 valves can be refurbished at a time. WNP-2 has 18 valves with which to satisfy the 12 valve operable LCO. Refurbishment of a seventh valve would mean that the present LCO (12 valves operable) could not be met and entry into Operational Conditions 1, 2 or 3 would be prohibited until the seventh valve was tested and declared operable; a situation requiring Operational Condition 1. Therefore taking more than six valves out of service at a time is not feasible with the present.

technical specification.

9gPg1901 poR ADOCK 0 5000397 poc

Page Two RE(UEST FOR AMENDMENT TO TS 3/4.4.2 SAFETY/RELIEF VALVES Should there be a need to refurbish more than six valves during an outage with the present technical specifications an unnecessary startup and shutdown cycle is required and return to full power is delayed. Refurbishment of seven or more would require six to be removed at the start of an outage, refurbished and reinstalled. At that point the plant would need to restart, attain operating pressure and temperature, and prove operable by. test the 6 valves initially refurbished. In order to refurbish the remainder (that number greater than six) the plant would then be shutdown, cooled down and the second set removed for refurbishment. The plant would remain shutdown until the removed valves were reinstalled and then would proceed to power to test and prove operable the second set of valves. In this manner twelve valves would remain operable at all times.

As shown by Attachment 2, four valves operable, at power below 25% rated thermal power, will ensure that the maximum vessel pressure experienced due to rapid closure of the mainsteam isolation valves is well below the pressure safety limit and bounded by the design bases event described in the WNP-2 FSAR Section 15.2.4.

The Supply System has reviewed those events creating pressure transients and determined that the accident analyzed in attachment 2 is the most bounding accident given the initial conditions. Accordingly approval of the requested change will allow more flexibility in safety relief valve maintenance and outage scheduling and preclude the possibility of an unnecessary plant cycle and delayed return to service. Approval of the requested amendment would allow 7 or more valves (up to a maximum of 14) to be refurbished at one time and not restrict movement into Operational Condition 1 as long as power remained below 25% Rated Thermal Power.

The Supply System has evaluated this amendment request per 10CFR 50.92 and determined that it does not represent a significant hazard because it does not:

1) Involve a significant increase in the probability or consequences of an accident previously evaluated. This requested amendment does not increase the probability of an accident previously evaluated because it does not impact equipment in a way that may potentially initiate an accident.

Further it does not increase the consequences of a previously evaluated accident because as shown in the Attachment 2 analysis the peak reactor pressure resulting from the most severe pressurization event is well below the pressure safety limit. Power distribution limits are not of concern because the change is only applicable at low power conditions and bounded by the design bases event described in the WNP-2 Safety Analysis. Therefore, this proposed change will not involve a significant increase in the probability or consequences of an accident previously evaluated.

2) Create the possibility of a new or different kind of accident previously evaluated. This requested amendment does not result in any hardware changes to equipment that upon failure or misoperation could initiate a new or different kind of accident. It involves changes to equipment that responds to accident conditions and the response, as shown in the attached analysis, is within acceptable values. No new modes of operation result from this

Page Three

~ ~

RE(VEST FOR AHENDHENT TO TS 3/4.4.2 SAFETY/RELIEF VALVES U

3) Involve a significant reduction in a margin of safety. As described in the attached analysis the maximum vessel pressure from the most severe overpressure transient at the low power conditions, to which this change applies, is much lower than the maximum vessel, pressure from the Design Bases Event (WNP-2 FSAR 15.2.4). As such, there is no reduction in safety margin with the approval of this change.

As discussed above, the Supply System considers that this change does not involve a significant hazards consideration, nor is there a potential for significant change in the types or significant increase in the amount of any effluents that may be released offsite, nor does or cumulative occupational radiation it involve a significant increase in individual exposure. Accordingly, the proposed change meets the eligibility criteria for categorical exclusion set forth in 10CFR 51.22(c)(9) and therefore, per 10CFR 51.22(b), an environmental assessment of the change is not required.

This Technical Specification change has been reviewed and approved by the'NP-2 Plant Operations Committee (POC) and the Supply System Corporate Nuclear Safety Review Board (CNSRB). In accordance with 10CFR 50.91, the State of Washington has been provided a copy o'f this letter.

The Spring 1990 refueling outage is currently scheduled for April 15, 1990 and in order to provide the maximum flexibility in outage planning and SRV maintenance, approval of this amendment is requested by March 15, 1990.

Very truly yours, G. C. Sorensen, Manager Regulatory Programs PLP/bk Attachments cc: JB Hartin - NRC RV NS Reynolds - BCP&R RB Samworth - NRC DL Williams - BPA/399 NRC Site Inspector - 901A C Eschels - EFSEC

4'I Lv VP STATE OF WASHINGTON)

Subject:

y COUNTY OF BENTON

)

)

y. S. ~If, g2 I, G. C. Sorensen, being duly sworn, subscribe to and say that I am the Manager, Regulatory Programs, for the WASHINGTON PUBLIC POWER SUPPLY SYSTEM, the applicant herein; that I have full authority to execute this oath; that I have reviewed the foregoing; and that to the best of my knowledge, information, and belief the statements made in it are true.

DATE F cJA 1990 G. C. Sorensen, Manager Regulatory Programs On this day personally appeared before me G. C. Sorensen, to me known to be the individual who executed the foregoing instrument, and acknowledged that he signed the same as his free act and deed for the uses and purposes herein mentioned.

GIVEN under my hand and seal this ~ g{

day of J ~ua 1990.

Notary ub s c s n nd or the STATE OF WASHINGTON Residing at My commission expires 7 1 91

e 4

s II s ~ 4ogq 4

~+

Vg

/

4 g 4~p /

,t l, )

ATTACHMENT 1 I