ML18227D810

01/18/1978 Letter Proposed Amendment to Section 3.D.1 of Operating License to Require Steam Generators to Be Inspected During Next Refueling Outage or Sooner If Warranted by Operating Experience

ML18227D810
Person / Time
Site:	Turkey Point
Issue date:	01/18/1978
From:	Robert E. Uhrig Florida Power & Light Co
To:	Stello V Office of Nuclear Reactor Regulation
References
L-78-23
Download: ML18227D810 (8)

Text

REGULATORY INFORMATION DISTRIBUTION SYSTEM <RIDS)

DISTRIBUTION FOR INCOMING MATERIAL 50-251 REC: STELLO V ORG: UHRIG R E DOCDATE: 01/18/78 NRC FL PWR 8( LIGHT DATE RCVD: Oi/24/78 DOCTYPE: LETTER NOTARIZED: YES COPIES RECEIVED

SUBJECT:

LTR 3 ENCL 40 LICENSE NBR DPR-41 AMEND TECH SPECS CHANGE CONCERNING REVISION OF UNIT 4 STEAM 6 PLANT NAME: TURKEY POINT UNIT 4 REVIEWER INITIAL: XEF DISTRIBUTOR INITIAL:

DISTRIBUTION OF THIS MATERIAL IS AS FOLLOWS GENERAL DISTRIBUTION FOR AFTER ISSUANCE OF OPERATING LICENSE.

(DISTRIBUTION CODE A001)

FOR ACTION: BRANC C IEF LEAR++W/7 ENCL INTERNAL: REG FILE++W/EN NRC PDR++W/ENCL 0 CL OELD44LTR ONLY HANAUER++W/ENCL CHECK++W/ENCL E I SENHUT4~4 W/ENCL SHAO44W/ENCL BAER++W/ENCL BUTLER4+W/ENCL GR IMES44 W/ENCL J. COLLINS<4 W/ENCL J. MCGOUGH++W/ENCL EXTERNAL: LPDR S MIAMI FL4+W/ENCL TIC~~W/ENCL NSIC+4W/ENCL ACRS CAT B++W/16 ENCL DISTRIBUTION: LTR 40 ENCL 39 CONTROL NBR: 780260101 SIZE: 4P

%%%%%%%%%%%4 %%%4%4 4 4%%4%%%%%%%4 4%4 4 THE END

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~Cc FLORIDA PGWER & LIGHT COMPANY January 18, 1978 L-78-23 Director of Nuclear Reactor Regulation /

Attention: Mr. Victor Stello, Director Division of Operating Reactors U. S. Nuclear Regulatory Commission Washington, DC 20555

Dear Mr. Stello:

Re: Turkey Point Unit. 4 Docket No. 50-251 Operatin License DPR-41 In accordance with 10 CFR 50.30, Florida Power 6 Light Company submits herewith three (3). signed originals and forty (40) copies of a request to amend Facility Operating License DPR-41. The proposed amendment to Section 3.D.1 of Operating License DPR-41 would require that the Unit 4 steam generators be inspected during the next refueling outage or sooner that an inspection was warranted.

if operating experience showed The proposed change to the Operating License is described in the following paragraph:

1. STEAM GENERATOR OPERATION Unit No. 4 steam generators shall be inspected during the next refueling outage or sooner in the event, the limitations of Sections 2 and 4 below are exceeded.

Nuclear Regulatory Commission approval shall be ob-tained before resuming power operation following this inspection.

Florida Power 6 Light Company, in conjunction with its NSSS vendor and other utilities, has been engaged in an extensive program de-signed to enhance our understanding of the denting phenomenon. As a result of this program, a scheme of preventively plugging steam generators has been implemented.

The preventive plugging program which has been implemented on Unit 4 has been judged to be overly conservative with respect to justifying a six-month operating interval. Since that time, empirical evidence (i.e., operating'istory at Turkey Point Unit 4 and inspec-tion results at Surry) has" confirmed the current plugging pattern to be overly conservative and capable of providing for safe operations PEOPLE... SERVING PEOPLE

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Director of Nuclear Reactor Regulation Attention: Mr. Victor Stello, Director Division of Operating Reactors Page Two beyond the six effective operating months. Turkey Point Unit 4 has been shutdown only once to repair a tube leak during the past five months of operation. Steam Generator 4A presently has indications of a small primary-to-secondary leak. This leakage frequency is less than predicted and proves that no increase in steam generator degradation rate has occurred.

We have concluded through our denting studies and actual operating experience that the denting phenomenon does not result in catastrophic tube failures. Tube failure due to the denting phenomenon is characterized by a slow increase in primary-to-secondary leakage.

This leakage is easily detected allowing the unit to be shut down and the leak repaired without exceeding any operating parameters.

Significant degradation of the steam generators would be indicated by an increase in the frequency of tube leaks. The existing operat-ing limits ensure that leakage rates remain low enough to assure safe and orderly shutdowns, and the required evaluations during shutdowns would provide assessment of current steam generator integrity, should leaks occur.

Florida Power 6 Light Company has determined that a steam generator inspection should be performed during each refueling outage, and that an inspection should be performed sooner only when warranted by actual operating experience.

Inspecting steam generators prior to the refueling outage would cost consumers 10-12 million dollars in replacement energy costs.

This inspection would also result in employee radiation exposure of approximately 20-50 man rem.,- In addition, the steam generators would be exposed to an oxygenated environment during the inspection, thus accelerating any corrosion processes which may be occurring.

The 'Zurkey Point, Plant Nuclear Safety Committee and the Florida Power 6 Light Company Nuclear Review Board have reviewed this amendment. request and have made the following determinations:

1) A steam generator inspection at this time is not necessary based on operating experience.

2) A steam generator inspection is not required at, six-month intervals to ensure that the health and safety of the public are protected.

3) An inspection involves considerable impact in terms of employee man-rem exposures and increased fuel costs to the public.

Di.rector of Nuclear Reactor Regulation Attention: Mr. Victor Stello, Director Division of Operating Reactors Page Three

4) An inspection may increase the denting rate.

5) A steam generator inspection should be performed at Turkey Point only at each refueling unless a more frequent inspection is indicated by actual operating experience.

6) The steam generator operating limitations as amended by this request are sufficient, to ensure that the health and safety of the public are protected.

The review bodies concluded that continued operation of Unit 4 in accordance with the operating license as revised will not endanger the health and safety of the public, and will result in a significant economic benefit to the public.

Very truly yours, Robert E. Uhrig Vice President REU/GDW/RJA:ltm Enclosures cc: Robert Lowenstein, Esq.

J. P. O'Reilly

STATE OF FLORIDA )

) ss.

COUNTY OF DADE )

Robert E. Uhrig, being first duly sworn, deposes and says:

That he is a Vice President of Florida Power & Light Company, the Licensee herein; That he has executed the foregoing document; that the state-ments made in this said document are true and correct to the best of his knowledge, information, and belief, and that he is authorized to execute the document on behalf of said Licensee.

Robert E. Uhrig Subscribed and sworn to before me this

~Foray oE NOTARY PUBLIC, in and for the County of Dade, State of Florida tfOTATIY Pusuc STAm OI'.OIIIOa IIE tAIIGE MY COMMISSION EXPIRES OCTOBER 2, IBSI My COmmiSSiOn eXPireS: soNoEo TNRu MAYNARo Bo:IONo ABENOY

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