ML20100K287

Response to TMI Alert Demand for Adjudicatory Hearing Re Plugging Criteria for Steam Generator Tubes.Hearing Should Be Denied.Nrc Should Complete Review of Request & Determine If Tech Spec Needed.Certificate of Svc Encl

ML20100K287
Person / Time
Site:	Three Mile Island
Issue date:	04/09/1985
From:	Churchill B GENERAL PUBLIC UTILITIES CORP., SHAW, PITTMAN, POTTS & TROWBRIDGE
To:	NRC COMMISSION (OCM)
References
CON-#285-493 OLA, NUDOCS 8504120389
Download: ML20100K287 (11)

Text

'N99i3 6 April 9, 1985 C D E Er UNITED STATES OF AMERICA WMC NUCLEAR REGULATORY COMMISSION Before the Commission T5 AN 11 N1:52 GFfiCE 0f iLCRiiia In the Matter of ) 00CKEi M 4 SE NIU

} EJANCH METROPOLITAN EDISON COMPANY, ET AL.) Docket No. 50-289 - S (Three Mile Island Nuclear Station,)

) och Unit No. 1)

LICENSEE'S RESPONSE TO TMIA'S DEMAND FOR ADJUDICATORY HEARING By letters of January 31 and March 1, 1985, attached, GPU Nuclear Corporation (" Licensee") requested approval from the NRC Staff for revision of the threshold criteria (" plugging criteria")

for determining when plugging or other repair of Three Mile Island, Unit 1, steam generator tubes is required. Licensee's position, as set out in the above referenced letters 7.nd related documentation, is that the proposed revision does not require a change in the Technical Specifications of the operating license, and does not involve an unreviewed safety question as defined in 10 C.F.R. S 50.59 (and thus does not involve significant hazards considerations as defined in 10 C.F.R. S 50.92). The staff has not yet made a determination on Licensee's request, and has not yet set forth its position on whether or not it believes an amendment to the Technical Specifications is necessary. Mean-while, Licensee, by letter dated March 29, 1985, attached, has informed the Staf f that the TMI-l steam generator tubes are now B504120389 850409 PDR ADOCK 05000289

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being plugged in accordance with the plugging criteria as currently l set out in the Technical Specifications.

On March 26, 1985, Three Mile Island Alert, Inc., filed a demand for a hearing on Licensee's request for approval of its proposed plugging criteria. The hearing demand is premature.

Until the staff completes its review of Licensee's request and determines whether an amendment to the technical specifications is required and, if so, whether significant hazards considerations are involved, there is no controversy which is ripe for adjudica-tion.

Accordingly, the March 26 Demand for Hearing should be denied without prejudice to TMIA's right, if any, to file a request for hearing following a staff determination on Licensee's request.

Licensee will respond in substance at that time to any such request for hearing.

Respectfully submitted, SHAW, PITTMAN, POTTS & TROWBRIDGE

{

By V

' Gedtge Pv-Trowbridge, P.C.

Bruce W. Churchill, P.C.

Counsel for Licensee 1800 M Street, N.W.

Washington, D.C. 20036 l

(202) 822-1000

Dated

April 9, 1985 i

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"%PETEL UNITED STATES OF AMERICA NUCLEAR REGULATORY COMMISSION Before the Commission 0FHCE OF SECstilAFP-DOCKETt In the Matter of ) &]Ef1VICI

)

METROPOLITAN . EDISON COMPANY, ET _AL.)

Docket No. 50-289 (Three Mile Island Nuclear Station,)

Unit No. 1)

CERTIFICATE OF SERVICE This-is to certify that copies of the foregoing " Licensee's Response to TMIA's Demand for Adjudicatory Hearing" were served, by deposit in the United States mail, first class, postage pre-paid, to all those on the attached Service List, this 9th day of April, 1985.

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-Brucd W Churchill, P.C.

Dated: April 9, 1985 i

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v UNITED STATES OF AMERICA NUCLEAR REGULATORY COMMISSION Before the Commission In the Matter of )

)

METROPOLITAN EDISON COMPANY, ET AL.)

Docket No. 50-289 (Three Mile Island Nuclear Station,)

Unit No. 1)

SERVICE LIST Nunzio J. Palladino, Chairman Dr. Reginald L. Gotchy U.S. Nuclear Regulatory Commission Administrative Judge Washington, D.C. 20555 Atomic Safety and Licensing Appeal Board Thomas M. Roberts, Commissioner U.S. Nuclear Regulatory Commission U.S. Nuclear Regulatory Commission Washington, D.C. 20555 Washington, D.C. 20555 Sheldon J. Wolfe James K. Asselstine, Commissioner Administrative Judge U.S. Nuclear Regulatory Commission Chairman, Atomic Safety and Washington, D.C. 20555 Licensing Board U.S. Nuclear Regulatory Commission Frederick Bernthal, Commissioner Washington, D.C. 20555 U.S. Nuclear Regulatory Commission Washington, D.C. 20555 Dr. David L. Hetrick Administrative. Judge Lando W. Zech, Jr., Commissioner Atomic Safety and Licensing Board U.S. Nuclear Regulatory Commission College of Engineering Washington, D.C. 20555 Dept. of Nuclear & Energy Engr.

The University of Arizona Gary J. Edles Tucson, Arizona 85721 Administrative Judge

' Chairman, Atomic Safety and Dr. James C. Lamb, III Licensing Appeal Board Administrative Judge U.S. Nuclear Regulatory Commission Atomic Safety and Licensing Board Washington, D.C. 20555 313 Woodhaven Road Chapel Hill, N.C. 27514 Dr. W. Reed Johnson Administrative Judge Mary E. Wagner, Esq.

Atomic Safety and Licensing Office of Executive Legal Director Appeal Board U.S. Nuclear Regulatory Commission '

U.S. Nuclear Regulatory Commission Washington, D.C. 20555 1 Washington, D.C. 20555 i

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o Commission Service List Page Two TMI-l' Atomic Safety and Licensing Appeal Board Panel U.S. Nuclear Regulatory Commission Washington, D.C. 20555 Atomic Safety and Licensing Board U.S. Nuclear Regulgatory Commission

- Washington, D.C. 20555 Docketing'and Service Section (3)

Office of the. Secretary U.S.. Nuclear Regulatory Commission Washington, D.C. .20555

-Joanne Doroshow, Esq.

Louise Bradford Three Mile. Island Alert, Inc.

315 Peffer-Street.

Harrisburg,'PA 17102 Thomas Y. Au Assistant-Counsel ~

, Commonwealth of Pennsylvania Department of Environmental Resources Bureau of Regulatory Counsel Room 505 Executive House P. O. Box 2357 Harrisburg, PA .17120

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Parsippany.New Jersey 07054 114 (2011263 6500 TELEX 136 482 Writer's Direct Dial Number January 31, 1985 l 5211-85-2023 , l RFW-0397 l l

Office of Nuclear Reactor Regulation  !

Attn: J. F. Stolz, Chief Operating Reactor Branch No. 4 Division of Licensing U.S. Nuclear Regulatory Commission Washington, DC 20555

Dear Mr. Stolz:

Three Mile Island Nuclear Station Unit 1 (TMI-1)

Operating License No. OPR-50 Docket No. 50-289 Steam Generator Repair Limits In various conversations with your staff we informed you that we intend to plug TMI-l steam generator tubes with indications in the free span which exceed the repair limit. Technical Specification 4.19.4.a.6 defines the repair limit as:

...the imperfection depth at or beyond which the tube shall be repaired or removed from service because it may become unserviceable prior to the next inspection. This limit is equal to 40% of the nominal tube wall thickness, unless higher limits are shown to be accJe table by analysis and approved by the NRC." (Emphasis added)

We have in the past repaired tubes based on the general 40%

through-wall repair limit. Detailed analyses have shown other, more specific limits to be acceptable to prevent a tube from becoming unserviceable prior to the next inspection. Therefore, in accordance with the provisions of Technical Specifications 4.19.4.a.6, GPU Nuclear requests staff approval of revised repair limit criteria which more accurately reflect the capability of the steam generator tubes, the capabilities of eddy current testing at THI-1, and the nature of the eddy current indications. The proposed criteria and their bases are set forth in the attached TDR-645, " Basis for Plugging and Stabilizing Criteria for OTSG Tubes," January 1985. i The current repair limit defincs as acceptable a tube with a defect extending up to 40% of the tube wall thickness. The defect may be up to 360* circumferential extent. This however is based on the state-of-the-art CPU Nucle 1r Corpcrat'en is a subs. diary of General Pobhc Ut.htics Cc'poration

current examination techniques and analyses typical of the mid 1970's. With today's eddy current technology, tube defects can be better characterized in terms of circumferential extent and volume, as well as through wall extent. 4 Recent analyses demonstrate the acceptability of tubes based on the extent of both depth and length of the defect. These analyses show that many tubes with defects exceeding 405 through wall are acceptable because they would not be a size or configuration at the time of ECT detection nor would they be during the interval between inspections to' adversely affect the required l degree of tube integrity. Hence, the proposed criteria are based on the total cross section of unimpaired tube wall remaining, rather than a consideration of through wall extent alone.

The analytical bases for the proposed criteria have been previously recognized and approved. These analyses have been documented in GPU '

Nuclear's TR-008, the safety evaluation for the kinetic expansion repair process, and in IftC's NUREG-1019. Both documents recognize that some tubes with greater than 405 through wall defects need not be repaired because the -

defect size would not significantly affect tube integrity.  !

While staff approval is required by Technical Specification 4.19.4.a.6, the proposed criteria for which we seek istC approval are not subject to the requirements of 10 CFR 50.59. Their use constitutes neither a change in facility or the procedures as described in the safety analyses report for IMI-1. We have, nevertheless, evaluated the criteria in

, accordance with the provisions of section 50.59.

i Use of the proposed criteria does.not require a change in the technical specifications, and does not involve an unreviewed safety question as defined in section 50.59. Use of the criteria does not involve the possibility of an accident or malfunction not previously evaluated or an increase in the consequences of an accident. As shown in the attached TOR-645 the margin of safety, for the proposed criteria is no less than the licensing basis for the current repair limit and hence the probability of occurrence of an accident or malfunction has not been increased.

The proposed repair limit is an application of a previously reviewed and approved technical approach. It reflects current detection capabilities and a more appropriate measure of tube integrity which does not reduce safety margins. We are now in the process of plugging and stabilizing those l tubes which must be removed from service based on this proposed criteria, j and therefore request that you give our request prompt consideration.

i icerc ,

. . I n Director, Technical Functions dis:0991f Attachment cc: R. Conte H. Silver Dr. T. Murley C. McCracken

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OPU Nuoleer Corporeden Nuclear 'a mi e- a ~r Parsiocany.New Jersey 070541149 ,i (201)263 8500 l TELEX 136 442 Writer's Direct 0'al Number March 1, 1985 5211-85-2047 Office of Nuclear Reactor Regulation Attn: J. F. Stolz, Chief Operating Reactor Branch No. 4 Division of Licensing U.S. Nuclear Regulatory Comission Washington, OC 20555

Dear Mr. Stolz:

Three Mile Island Nuclear Station l' nit 1 (TMI-1)

Operating License No. OPR-50 Docket No. 50-289 Steam Generator Repair Limits Technical Specification 4.19.4.a.6 defines the limit for repair or removal from service of OTSG tubes at TMI-l as the following:

... the imper'fection depth at or beyond which the tube shall be repaired or removed from service because it may become unserviceable prior to the next inspection. This limit is equal to 40% of the nominal tube wall thickness, unlesU higher limits are shown to be acceptable by analysis and approva' by the NRC" (Empnasts added).

In the past, GPU Nuclear Corporation (GPUN) has repaired tubes based on the general 405 through wall repair limit. However, detailed analyses have shown other, more specific limits to be acceptable to prevent a tube from becoming unserviceable prior to the next inspection. Therefore, in Reference 1 GPUN. requested staff approval of revised repair limit criteria which more accurately reflect the capability of the steam generator tubes, the capabilities of eddy current testing at TM!-1, and the nature of the eddy current indications. These proposed criteria and their bases were set forth in TDR-645, " Basis for Plugging and Stabilizing Criteria for OTSG Tubes," which was attached to Reference 1. g u!AR 8 1985 L+RA/C.H.B.

GPU Nucmar Corporation is a suDscary of General P9bhc Ubbties Corcoration

-- - _.__~ - . . . . - . . .- __ - _

j Based on our meeting with you and members of your staff on February 19, 1985, and subsequent telephone discussions, we understand that NRC review of our request is continuing. To facilitate the NRC review we )

propose that you consider a " staged" approach to approval of our request.

Eddy current testing (ECT) and examination would follow each stage,  ;

' supporting your continued evaluation, with the testing and reporting of ECT

' results in accordance with TR-008 (Reference 2). The first proposed stage is that period up to the first eddy current examination after connancement

of power operation, as defined by item 2.8.4 of Amendment 103 to Facility Operating License No. DPR-50 (Reference 3).

Prior to restart, GPUN intends to deoxygenate the primary reactor coolant-system, perform a steady state krypton leak test which involves maintaining the primary system at approximately 500'F for several days to measure primary / secondary leak rate and reconfirm the leak tightness of the steam generators, and conduct a controlled cocidown either to lay up or to commence hot functional testing with a favorable NRC restart decision. The results of the leak rate measurements will te reported to the NRC.

Since the original 100% baseline inspection of the OTSG tubes in 1982, the tubes have been subjected to mechanical loading during the kinetic expansion process and thermal and hydraulic loads during two hot functional tests. Subsequent addy current testing of the OTSG tubing was begun in November 1984.

As discussed in TDR-638 (Reference 4) which has been endorsed by NRC (Reference 5), results of these recent eddy current tests do not indicate any trends of indication growth of previously reported

- indications. The eddy current data and visual observations are consistent with a mechanism whereby previously existing areas of intergranular attack are made more detectable by mechanical loading during kinetic expansion and thermal and hydraulic loading from cooldown following hot functional testing. The loads on the tubes associated with the deoxygenation and i

krypton testing process would be small in comparison, and results of addy current meaningful testing datafollowing points. these processes would not be expected to represent Thus, GPUN does not consider eody current testing of the tubes appropriate following the deoxygenation and krypton testing processes. We therefore recomend that NRC approve use of the Reference 1 revised plugging criteria for the period up to the first addy current examination following connencement of power operation, while NRC review of the plugging criteria for subsequent periods oi operation continues.

truly yours, i

i D  %,- -

. F. Wilton Ofractor - Technical Functions SK: dis:1475f Y

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References 1.

GPUN Letter 5211-85-2023, R. F. Wilson to J. F. Stolz, " Steam Generator Repair Limits, January 31, 1985. -

2.

GPUN Topical Report 008, " Assessment of TMI-l Plant Safety for Return to Service After Steam Generator Repair," Rev. 3 August 19, 1983.

3.

USNRC Letter, John F. Stolz to H. D. Hukill, " License Amendment No.103, Steam Generator Tube Repairs and Return to Operation Three Mile Island Nuclear Station Unit 1 (TMI-1)," December 21, 1984.

4.

GPUN Letter 5211-85-2010, R. F. Wilson to J. F. Stolz, " Steam Generator Eddy Current Test Result Evaluation," January 14, 1985.

5.

NRC Staff Brief in Response to TMIA, in the Matter of Metropolitan January company, Edison 24, 1985. et. al. (Three Mile Island Nuclear Station, Unit No. 1),

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Parscoany.New Jerseyo7054 t149 l (201)263 6500 TELEX 136 482 Writers Direct Def Number:

March 29,1985 i

5211-85-2067 Office of Nuclear Reactor Regulation Attn: J.F.Stolz, Chief Operating Reactor Branch No. 4 Division of Licensing U.S. Nuclear Regulatory Comission Washington, D.C. 20555

Dear Mr. Stolz:

Three Mile Island Nuclear Station Unit 1 (TMI-1)

Operating License No. DPR 50 Docket No. 50-289 Steam Generator Repair Limits By letters dated January 31 and March 1,1985, GPU Nuclear Corporation requested approval of revised repair criteria, i.e., plugging limits, for the steam generator tubes. As documented in those letters, this approach is technically sound and does not constitute an unreviewed safety question. We have reached the point, however. where we must act now to avoid any potential ifmitations on TM1-1 plant readiness for restart. Accordingly, I have determined to proceed immediately to plug the steam generator tubes in accordance with the existing repair limits specified in Technical Specification paragraph 4.19.4.a.6. of the operating license.

We ask that the staff continue its technical review of our request so as to help us avoid unnecessary plugging in the future.

We will advise you when the plugging has been ccmpleted.

Very truly yours, ee. &

P.R. Clark President PRC/mak GPU Nutte c Co,puret.on is a svLvd; dry of Generaf PubHc Utl4 ties Corporation

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