ML17289A272

Application for Amend to License NPF-21,revising Tech Spec 4.6.1.4.c Re MSIV Leakage Control Sys

ML17289A272
Person / Time
Site:	Columbia
Issue date:	01/21/1992
From:	Sorensen G WASHINGTON PUBLIC POWER SUPPLY SYSTEM
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
Shared Package
ML17289A273	List: ML17289A272 ML17289A274
References
GO2-92-015, GO2-92-15, NUDOCS 9201280306
Download: ML17289A272 (7)

Text

ACCELERATED DI TRIBUTION DEMONS~TION SYSTEM REGULATORY INFORMATION DISTRIBUTION SYSTEM (RIDS)

ACCESSION NBR:9201280306 DOC.DATE: 92/01/21 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 4.6.1.4.c re MSIV leakage control sys.

DISTRIBDTION CODE: AOOID TITLE: OR COPIES RECEIVED:LTR Submittal: General Distribution iENCL j SIZE:

NOTES RECIPIENT COPIES RECIPIENT COPIES ID CODE/NAME LTTR ENCL ID CODE/NAME LTTR ENCL PD5 LA 1 1 PD5 PD 1 1 ENG,P.L. 2 2 INTERNAL: ACRS 6 6 N RR/DET/ECMB 7D 1 1 NRR/DET/ESGB 1 1 NRR/DOEA/OTSB11 1 1 NRR/DST 8E2 1 1 NRR/DST/SELB 7E 1 1 NRR/DST/S ICB8H7 1 1 NRR/DST/SRXB 8E 1 1 NUDOCS-ABSTRACT 1 1 OC/LFMB 1 0 OGC/HDS1 1 0 1 1 RES/DSIR/EIB 1 1 EXTERNAL: NRC PDR 1 1 1 1 R

D D

NOTE TO ALL "RIDS" RECIPIENTS:

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

TOTAL NUMBER OF COPIES REQUIRED: LTTR 24 ENCL 22

0 WASHINGTON PUBLIC POWER SUPPLY SYSTEM P.O. Box 968 ~ 3000 George Washington Way ~ Richland, Washington 99352 January 21, 1992 G02-92-015 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 REQUEST FOR AMENDMENT TO TECHNICAL SPECIFICATION 4.6.1.4 HSIV LEAKAGE CONTROL SYSTEM

References:

1) Letter, G02-92-013, JW Baker (SS) to MJ Virgilio (NRC),

"Request for Waiver of Compliance Relative to Technical Specification 4.6. 1.4 HSIV Leakage Control System",

dated January 16, 1992

2) Letter, G02-75-238, NO Strand (SS) to OD Parr (NRC),

"Response to Request for Information Main Steam Isolation Valve Leakage Control System", dated August 18, 1975 In accordance with the Code of Federal Regulations, Title 10, Parts 50.90, 2. 101, and 50.91(a)(5), the Supply System hereby submits a request for amendment to the WNP-2 Technical Specifications on 'an emergency basis as provided for in the regulations. Specifically, the Supply Sy'tem is requesting that the Technical Specification Surveillance Requirement 4.6. 1.4.c'be revised to more accurately address the acceptance criteria for capacity of the blowers in the MSIV Leakage Control System (HSLC).

On January 16, (Reference 1) the Supply System requested relief from the Technical Specification MSLC surveillance requirement that each MSLC blower develop at least 30 scfm with the understanding that the request for amendment to the Technical Specification would be submitted on January 21. Reference 1 stated the correct value is 30 cfm. On January 16, the waiver was received by the Supply System during a telephone call with the NRC, supporting the acceptance criteria of 30 cfm for the blower.

920i28030h 'P20i2i PDR ADOCK 05000397 P PDR Pyc I I/g

Page Two RE(VEST FOR AMENDMENT TO TECHNICAL SPECIFICATION 4.6.1.4 HSIV LEAKAGE CONTROL SYSTEM As described in WNP-2 FSAR in Section 6.7.2, the HSLC system is designed to minimize the release of fission products from the main steam line which could bypass the standby gas treatment system (SGT) after a LOCA. This is accomplished by directing leakage from the closed main steam isolation valves (HSIVs) through a bleed line to the SGT system. The flow is effected by blowers that maintain the pressure in the steam lines at a slight vacuum, ensuring that the HSIV leakage will pass through the blower and the SGT system prior to release to the

'tmosphere. The HSLC system is designed with sufficient capacity and capability to control the leakage from the main steam lines, consistent with containment integrity under the conditions associated with the postulated design basis LOCA.

Each MSLC subsystem will add about 30 scfm of load to the SGT system, which is less than 2% of the rated capacity of SGT and is compatible with the SGT temperature and humidity limits.

Section 6.7,2.3 of the FSAR states that the MSLC system blowers provide a flow rate of approximately 30 cfm at about -17 inches HzO suction pressure. The design specifications discussed in Reference 2 require the system to accommodate a leak rate of five times the Technical Specification leakage allowed for the MSIVs, This value of 11.5 scfh per each valve, or 230 scfh, equals 3.8 scfm (Reference 2). When corrected for worst case pressure, temperature and humidity expected to be seen as surveillance testing conditions, the flow would never exceed an indicated value (uncorrected reading from local flow instrumentation) of 5 cfm. A recent Supply System review of Burns and Roe (architect engineer for WNP-2) Engineering documentation has confirmed that the correct units for the surveillance acceptance criteria are "cfm" rather than "scfm".. Therefore, the proposed 30 cfm acceptance criterion provides significant margin to the design basis requirements. Additionally, this proposed criterion will not cause or mask any operational problems for the installed equipment, Currently, this surveillance requires that at least once per 18 months the HSLC subsystem be demonstrated OPERABLE by verifying that the blower develops at least the following required vacuum at the rated capacity:

a) Inboard valves, 17" H,O at 30 scfm b) Outboard valves, 17" Hz0 at 30 scfm.

The surveillance criteria cannot be met without design modifications. The surveillance requirement should be revised to require each of. the 2 blowers develop at least -17" Hz0 at the fan suction with 30 cfm of dilution flow. (The minus sign is included in the sentence to clarify the actual vacuum require-ments.)

The Supply System has evaluated this amendment request in accordance with 10CFR50.92 and has concluded that changing the acceptance criterion from 30 scfm to 30 cfm do'es not involve a significant hazards consideration for the following reasons:

Page Three RE(VEST FOR AHENDHENT TO TECHNICAL SPECIFICATION 4.6.1.4 HSIV LEAKAGE CONTROL SYSTEH It would not involve a significant increase in the probability or consequences of an accident. The HSIV Leakage Control System is a loss-of-coolant accident (LOCA) mitigation feature that cannot cause an accident. It will not increase the consequences of a LOCA as the required 30 cfm is considerably in excess of the design requirement for the system.

The system has been shown to provide for adequate removal and treatment of HSIV leakage (FSAR Table 15.6-16).

It would not create the possibility of a new or different kind of accident. As an accident mitigation feature the proposed change cannot cause a new kind of accident. It cannot result in a different kind of accident because as discussed above, 30 cfm satisfies the design requirement for the system.

It would not create a significant decrease in a margin of safety because the proposed 30 cfm acceptance criterion is significantly in excess of the 3.8 scfm requirement based upon the requirement established in the Reference to accommodate five times the Technical Specification leakage 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 it involve a significant increase in individual or cumulative occupational radiation 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 WNP-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 of this letter.

Very truly yours, G. C Sorensen, Hanager Regulatory Programs HGE/bk Attachments CC: JB Hartin - NRC RV NS Reynolds - Winston 8 Strawn PL Eng - NRC DL Williams - BPA/399 NRC Site Inspector - 901A RG Waldo - EFSEC

l4 STATE OF WASHINGTON)

Subject:

Request for Amend. to TS

) MSIV Leaka e Control S stem COUNTY OF BENTON )

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 the full autho'rity 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 +r Zuni 1992 G. C. So ensen, Manager Regulatory Programs On this date 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 ~day of 1992.

o ary Public=. ig and'or the STATE OF WASHINGTON .

s'v'C g

~t.J,~ I

~'esiding at Kennewick Washin ton My Commission Expires A ril 28 1994

hh 1

ph