ML17278A236

Application for Amend to License NPF-21,changing Tech Spec 3.8.4.2 to Reflect Recent Changes in Surveillance Testing Re Use of Fuses as Overcurrent Protection Devices.Fee Paid

ML17278A236
Person / Time
Site:	Columbia
Issue date:	06/13/1985
From:	Sorensen G WASHINGTON PUBLIC POWER SUPPLY SYSTEM
To:	Butler W Office of Nuclear Reactor Regulation
Shared Package
ML17278A237	List: ML17278A236 ML17278A238
References
GO2-85-312, TAC-57993, TAC-63052, NUDOCS 8506260377
Download: ML17278A236 (12)

Text

REGUL'NFORMATION DISTRIBUT'STEM (RIDS)1 ACCESSION NBR:8506260377 DOC~DATE: 85/06/13 NOTARIZED!

YES DOCKET FACIL:50-397 NPPSS Nuclear Projects Unit 2i liashington Public Powe 05000397 AUTH INANE AUTHOR AF FILIATION SORENSEN<G.C, Washington Public Power Supply System RECIP~NAME RECIPIENT AFFILIATION BUTLER HE R Licensing Branch 2

SUBJECT:

Application for amend to License NPF-21rchanging Tech'pec 3.8,4.2 to reflect recent changes in surveillance testing re use of fuses as overcurrent protection devices,Fee paid+" DISTRIBUTION CODE: A001L COPIES RECEIVED:LTR ENCL SIZEo TITLE: OR Submittal:

General Distribution NOTES: OL e 1'2'/20/83 05000397 RECIPIENT ID CODE/NAME NRR LB2 BC 01 INTERNAL: ACRS 09 ELD/HDS2 NRR/DL DIR NRR/DL/TSRG NRR/DS I/RAB RGN5 COPIES LTTR ENCL 7 7 6 6 1 0 1 1 1 1 1 1 1 1 REC IP IENT ID CODE/NAME ADM/LFMB NRR/DE/MTEB NRR/DL/DRAB N ETB EG FIL 00 ,COPIES LTTR ENCL 1 0 1 1 1 0 1 1 1 1 EXTERNAL;24X LPDR NSIC 03 05 1 1 1 1 1 1 EG8G BRUSKEiS NRC PDR 02 1 1 1 TOTAL NUMBER OF COPIES REQUIRED: LTTR 28 ENCL 25 Wt h W Washington Public Power Supply System P.O.Box 968 3000 George Washington Way Richland, Washington 99352 (509)372-5000 June 13, 1985 G02-85-312 Docket No.50-397 Director of Nuclear Reactor Regulation Attention:

Mr.W.R.Butler, Chief Licensing Branch No.2 Division of Licensing U.S.Nuclear Regulatory Commission Washington, D.C.20555

Subject:

NUCLEAR PLANT NO.2 RE(VEST FOR EMERGENCY TECHNICAL SPECIFICATION CHANGE TO TECHNICAL SPECIFICATION 3.8.4.2, PRIMARY CONTAINMENT PENETRATION CONDUCTOR OVERCURRENT PROTECTIVE DEVICES In accordance with the Code of Federal Regulations, Title 10, Parts 50.90 and 2.101, the Supply System hereby requests an emergency change to the WNP-2 Technical Specifications.

Specifically, the Supply System is requesting a change to Technical Specification 3.8.4.2 to reflect recent changes in sur-veillance testing with regard to the use of fuses as overcurrent protection devices.Testing for the first eighteen.(18}

month surveillances required by the WNP-2 Technical Specifications is now in progress.As a result, Surveillance Re-quirement 4:8.4.2.a.3 has prompted a review of the fuses listed in Table 3.8.4.2-1 (revised in Amendment 6 dated October 12, 1984 due to a change request from March 9, 1984).This review disclosed that as a result of certain plant modifications the fuses listed in the Table were replaced with larger fuses.Supply System design change procedures have ensured in all such cases that the new fuse sizing is within the design basest A safety analysis has been performed on each change to confirm that the design change remains within the design margin of the plant.The Supply System first became aware of the possible need for the requested technical specification change on June 6, 1985 and immediately commenced the internal review procedure which, resulted in this request.As a result, the opportunity to submit a change request through the normal process contemplated by Section 50.91 is not available.

The present outage will end on June 21.Consequently, a revision is.required to the subject technical specification on an emergency basis in order to resume operation.

The Supply System hereby 85ogg6{)377 Oggy7 r DR ADO" pDR P I Jl~~

W.R.Butler Page Two June 13, 1985 EMERGENCY TECH.SPEC.CHANGE TO TECH.SPEC.3.8.4.2, PRIMARY CONTAINMENT PENETRATION CONDUCTOR OVERCURRENT PROTECTIVE DEVICES requests an emergency change be granted in accordance with 10 CFR Parts 50.91(a)(5) and 2.106 to support WNP-2 starting up on June 21, 1985.This request is being sought promptly after the need for the technical specifica-tion modification was identified and the Supply System has not created this emergency to take advantage of Section 50.91(a)(5).

It appears in the judgment of the Supply System that startup will be delayed unless the requested amend-ment is granted by June 21, 1985.i The'physical nature of fuses brings into question the necessity of performance testing as presently required by the technical specifications.

Surveillance testing is appropriate for active overcur rent protective devices (such as circuit breakers)as degradation due to corrosion or deformation of components or"sticking" of electrical components is a legitimate concern.Surveillance testing provides a reasonable assurance that these active components will respond appropriately.

In contrast, a"calibrated" fuse is a passive component with known properties, built to prescribed physical dimensions in a sealed container.

The basic design, simple construction, and passive operation make the fuse inherently reliable.With respect to containment penetration over-current protection, fuse failure is a conservative event.Wash-1400, October 1975 substantiates this position by determining the conservative probability of a single fuse failure to open to be 1 x 10/demand.It should be noted that a sin)le fuse in series with a mechanical breaker (probability to open of 4 x 10./demand, reference:

IEEE 500-1977)has a combined probability of failure to open of 4 x 10/demand.Two fu~gs protecting a circuit provide a probability of failure to open of 1 x 10/demand.Given the total number of circuits involved and the frequency of demands, the combined probability of occurrence for a failure to protect a containment penetration is so low as to preclude a necessity for routine fuse surveillance.

Furthermore, the Supply System has not been able to identify an effective surveillance test that could be applied to fuses to verify the reliability of the fuse to protect primary containment penetrations from an overcurrent condition.

Resistance measurement of fuses is not practical.

Typical resistance readings of a 200 amp fuse is 370-400 micro-ohms.

Smell changes in the micro-ohm range are not reliably determined by field testing equipment and would not be i'ndicative of a truly degraded condition.

Additionally, any surveillance testing could involve r'emoving and replacing fuses as would a replacement requirement.

This could increase the risk of procedural errors.This situation, in the opinion of the Supply System, is more credible than a surveillance test identifying a fuse that could fail in a nonconservative manner.In summary, the Supply System considers that surveillance testing of fuses does not provide any added assurance of safe plant operation; performance of such unnecessary testing actually degrades plant operation and poses an additional burden on plant operations'or no apparent increase in safety.

k W.R.Butler Page Three June 13, 1985 EMERGENCY TECH.SPEC.CHANGE TO TECH.SPEC.3.8.4.2, PRIMARY CONTAINMENT PENETRATION CONDUCTOR OVERCURRENT PROTECTIVE DEVICES With regard to the listing of fuse sizes in the technical specifications, it appears that the listing is not required by 10 CFR 50.36.Specifically, paragraph (4)Design Features: "Design features to be included are those features of the facility such as materials of construction and geometr i c arrangements, whi ch, if altered or modified, would have a significant effect on safety...".The changing of a particular fuse utilized for containment overcurrent protection does not have a significant effect on plant safety.Design practices in effect at WNP-2, reviewed by the NRC and continually available for review, ensure that ,such changes remain within the design.,margin of the plant.This is precisely'he situation presently being related.'use'size changes were made and safety analyses.performed to ensure that the fuses were sized large enough to supply the associated-load, small enough to fail in'he event of a fault in the load and small enough to ensure containment penetration protection.

The changes were within design margin and did not constitute a change having a significant safety effect.These types of changes,,'changes within design margin not having significant'safety relevance, are within the purview of the licensee and should not be governed by technical specifications.

The listing of fuse sizes in the technical specifications:requires the reporting of such non-safety significant events'and involves the'regulator into an area of plant activity not originally intended.With these considerations, the Supply System requests the attached proposed technical specification removing fuse sizing and fuse surveillance testing be granted on an emergency basis to support star tup on June 21, 1985 and commercial operation on July I, 1985.The Supply System has reviewed this change per 10 CFR 50.59 and determined that no unreviewed safety questions will result from this amendment.

This technical specification change has been reviewed and approved by the WNP-2 Plant Operations Committee and the'upply System Corporate Nuc'lear Safety Review Board.The Supply System has reviewed this change per 10 CFR 50.92 and determined that it does not: I)Involve a significant increase in the probability or consequences of an accident previously evaluated because any change in overload current protection characteristics will'be in the conservative direction.

Previously evaluated events will remain bounding.Therefore no increases in probability or consequence is conceivable.

Design change processes and audits of such processes will continue to ensure changes'remain within design margins.2)Create the possibility of a new or different kind of accident than previously evaluated because no.new accident scenarios are credible.All changes remain within design margin and installed equipment remains the same.

1 V 4l ii I[

E W.R.Butler Page Four June 13, 1985 EMERGENCY RECH.SPEC.CHANGE TO TECH.SPEC.3.8.4.2, PRIMARY CONTAINMENT PENETRATION CONDUCTOR OVERCURRENT PROTECTIVE DEVICES 3)Involve a significant reduction in a margin of safety because the sizing of fuses within the design margin does not encroach on the overall margin of safety and the deletion of fuse surveillance testing in all likelihood, will improve plant performance while removing an administrative burden of no benefit to safety.This change does not involve a significant hazards consider ation.Example (i)P 14870 of the Federal Register, April 6, 1983, is cited as justification.

This change is administrative in that it changes the technical specification to achieve consistency within the intent of the'technical specifications.

This change more clearly defines the responsibility of the licensee and improves plantoperation~whileremoving an unnecessary requir'ement from the technical specifi-cations.The Supply System has evaluated this request in accordance with the criteria contained in 10 CFR 170.21 and has included a warrant for one hundred fifty dollars ($150.00)as initial payment for this application for amendment under Facility Category A (Power Reactors).

In accordance with 10 CFR 50.91, the State of Washington has been provided a copy~of this letter.h I J Should you have any questions, please contact Mr.P.L.Powell, Manager, llNP-2 Licensing.

Very truly yours, G.C.Sorensen, Manager Regulatory Programs PLP/tmh Attachments cc: JO Bradfute-NRC WS Chin-BPA C Eschels-EFSEC JB Martin-NRC RV E Revell-BPA NS Reynolds-BLCPBR AD Toth-NRC Site

STATE OF WASHINGTON

))COUNTY OF BENTON RE(VEST FOR EMERGENCY TECHNICAL SPECIFICATION CHANGE TO TECHNI-CAL SPECIFICATION 3.8.4.2, PRIMARY CONTAINMENT PENETRATION CONDUCTOR OVERCURRENT PROTECTIVE DEVICES

Subject:

I, P.L.POWELL, being duly sworn, subscribe to and say that I am acting for 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 June 13 , 1985 P.L.POWELL, Manag r WNP-2 Licensing On this day personally appeared before me P.L.POWELL 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 therein mentioned.

GIVEN under my hand and seal this day of , 1985.Notary P c in a d for he State of Washington Residing at

~~I'g~~r, H=F p~1 I~rp h.'I (~Y'L