ML17289A836

Application for Amend to License NPF-21,changing TS 3/4.3.7.6 Re Source Range Monitor Surveillance Criteria Specified in LCO to Incorporate Guidance in Rev 1 of GE Svc Info Ltr Covering Channel Rate Count

ML17289A836
Person / Time
Site:	Columbia
Issue date:	09/02/1992
From:	Sorensen G WASHINGTON PUBLIC POWER SUPPLY SYSTEM
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
Shared Package
ML17289A837	List: ML17289A836 ML17289A838
References
GO2-92-208, NUDOCS 9209140105
Download: ML17289A836 (9)

Text

ACCELERATED D " RIBUTION DEMON< RATION SYSTEM REGULATQ INFORMATION DISTRIBUTION STEM (RIDS)

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ACCESSION NBR:920'P140105 DOC. DATE: 92/09/02 NOTARXZED: YES DOCKET 0 FACXL: 50-397 MPPSS Nuclear Pro Jecti Unit 2i Mashington Public Poee 05000397 AUTH. NANE AUTHOR AFFILIATION SORENSENi G. C. 4lashing ton Public Power Supply System REC I P. NANE RECXP XENT AFFILXATXON Document Control Branch (Document Control Desk)

SUBJECT:

Application For amend to License NPF-21> changing TS 3/4. 3. 7. 6 re source range monitor surveillance criteria specified in LCO to incorporate guidance in Rev 1 of GE svc info ltr covering channel rate count.

DISTRIBUTION CODE: AOOID TITLE: OR COPIES'ECEIVED! LTR Submittal: General Distribution

'i ENCL / SIZE:

D NOTES:

RECIPIENT COPIES RECZPZENT COPIES

'ID CODE/NANE LTTR ENCL ID CODE/NANE LTTR ENCL PD5 LA 1 1 PD5 PD 1 1 DEAN> M. 2 2 INTERNAL: ACRS 6 6 NRR/DET'/ESGB 1 NRR/DOEA/OTSB11. 1 1 NRR/DST/SELB,7E'RR/DST/SRXB 1 1 NRR/DST/SICBSH7 1 1 1 1 NUDOCS-ABSTRACT 1 1 8E'C/LF 1 0 OGC/HDS1 1 0 01 1 1 RES/DS IR/EI8 1 1 EXTERNAL:. NRC PDR NSIC S

NOTE TO ALL "RIDS" RECIPIENTS:

PLEASE HELP US TO REDUCE WASTE! CONTACT THE DOCUMENT CONTROL DESK.

ROOM Pl-37 (EXT. 504-2065) TO ELIMINATEYOUR NAME FROM DISTRIBUTION LISTS FOR DOCUMENTS YOU DON'T NEED!

TOTAL NUMBER OF COPIES REQUIRED: LTTR 22 ENCL 20

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WASHINGTON PUBLIC POWER SUPPLY SYSTEM P.O. Bm968 ~ 3000George Wasbtngton Way ~ Rtcbland, Wasbtngton 99352C968 ~ (509)372-5000 September 2, 1992 G02-92-208 Docket No. 50-397 U.S. Nuclear Regulatory Commission Attn: Document Control Desk Washington, D.C. 20555 Gentlemen:

Subject:

WNP-2, OPERATING LICENSE NPF-21 RE(VEST FOR AMENDMENT TO TECHNICAL SPECIFICATION 3/4.3.7.6 SOURCE RANGE MONITORS

Reference:

1) General Electric Service Information Letter No. 478, "SRH Minimum Count Rate," dated December 16, 1988

2) Letter G02-92-016, dated January 21, 1992, GC Sorensen (SS) to NRC, "Request for Amendment to TS Limiting Condition for Operability 3/4.9.2 Source Range Monitor Operability, Re-fueling Operations"

3) Letter, dated April 10, 1992, WH Dean (NRC) to GC Sorensen (SS), "Issuance of Amendment for the Washington Public Power Supply System Nuclear Project No. 2 (TAC No. H82662)"

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. This proposal requests that source range monitor (SRM) surveillance criteria specified in the subject Limiting Condition for Operation be changed (as attached) to incorporate the Reference 1 Service Information Letter (SIL) guidance. The SIL guidance modifies the acceptable SRH channel count rate and signal-to-noise ratio values to maintain the General Electric design confidence level.

This same change was requested in Reference 2. However because the primary purpose of Reference 2 was to request changes in the Refueling Instrumentation Technical Specification SRM requirements to allow a complete core offload the applicability of the SIL guidance to Specification 3/4.3.7.6 was not recognized.

9209140105 92pgp2 PDR ADOCK 05000397 P

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I Page 2 RE(UEST FOR AMEND. TO TS LCO 3/4.3.7.6 SOURCE RANGE MONITORS The SRHs provide the operator with information relative to the neutron level at very low flux levels. As such, the SRH indication is used to determine the approach to criticality and when criticality is achieved. The SRHs provide monitoring of reactivity changes during fuel or control rod movement and give the control room operator early indication of unexpected subcritical multiplication that could be indicative of an approach to criticality. Although no credit is taken for SRM function in any WNP-2 design basis accident or transient analysis they do provide indication to the operator that aids in reactor control.

The Reference I SIL provides guidan'ce to modify the SRH count rate to ensure that the design 95% confidence level is maintained in verifying SRH operability. As stated in the SIL, the acceptable SRH count rate value based on signal-to-noise (S/N) ratio has not been consistent within the BWR community. As a result of inquiries from some BWRs, General Electric conducted studies showing that a 95%

confidence level can be preserved by specifying either 0.7 counts per second (cps) with a- S/N > 20 or 3 cps with a S/N > 2. As stated above, Reference 2 requested this change for Technical Specification 3/4.9.2 (Refueling Operations).

Reference 3 issued the change for implementation at WNP-2. The change is also appropriate for Specification 3/4.3.7.6.

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

I) Involve a significant increase in the probability or consequences of an accident previously evaluated. The SRH instrumentation is not assumed to be an initiator of any analyzed event. The SRH instrumentation provides monitoring of neutron flux levels to give the control room operator early indication of unexpected subcritical multiplication that could be indicative of an approach to criticality. As such, action could be taken on the indication to avert or minimize the consequences of the event.

However, the SRH function is not relied upon in any design bases or transient analysis. Rod motion interlocks and other instrumentation are relied on in the accident analysis to avert an accident. The change in acceptable count rate and signal-to-noise ratio preserves the confidence level of the General Electric design. As a result, the consequences of any analyzed events are unaffected because the change does not alter any system or component design assumptions or operation. Therefore, no significant increase in the probability or consequences of an accident previously evaluated will be involved.

2) Create the possibility of a new or different kind of accident from any accident previously evaluated. The proposed change in SRH count rate and S/N ratio values does not create the possibility of a new or different kind of accident from any previously evaluated because it does not change modes of plant operation or require physical modifications. The change preserves the original General Electric design confidence level. No new or different kind of accident is therefore credible.

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Page 3 RE(VEST FOR AHEND. TO TS LCO 3/4.3.7.6 SOURCE RANGE HONITORS

3) Involve a significant reduction in a margin of safety. The change in SRH count rate and S/N ratio values does not affect a margin of safety because the values preserve the original General Electric design confidence level.

Therefore, no margin of safety is impacted by this change.

As discussed above, the Supply System concludes 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 the change 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 10 CFR 51.22(C)(9) and therefore, per 10 CFR 51.22(b), an environmental assessment of these changes is not required.

This Technical Specification change request has been reviewed and approved by the WNP-2 Plant Operations Committee and the Supply System Corporate Nuclear Safety Review Board. In accordance with 10 CFR 50.91, the State of Washington has been provided a copy of this letter.

Very truly yours,

-Q/

G. C. So ensen, Hanager Regulatory Programs (Hail Drop 280)

PLP/bk Attachments cc: RG Waldo - EFSEC JB Hartin - NRC RV NS Reynolds - Winston S. Strawn RR Assa - NRC DL Williams - BPA/399 NRC Site Inspector - 901A

STATE OF WASHINGTON)

Subject:

Request for Amend to TS

) Source Ran e Monitors 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 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 1992 G. C. Sodensen, 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.

No u ic in and for the STATE OF WASHINGTON Residing at Kennewick Washin ton My Commission Expires A ril 28 1994

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