ML19250C256

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Forwards IE Bulletin 79-17,Revision 1, Pipe Cracks in Stagnant Borated Water Sys at PWR Plants. No Response Required
ML19250C256
Person / Time
Site: Crane Constellation icon.png
Issue date: 10/29/1979
From: Grier B
NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I)
To: Arnold R
METROPOLITAN EDISON CO.
References
NUDOCS 7911230105
Download: ML19250C256 (1)


Text

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UNITED STATES n sitou o

NUCLEAR REGULATORY COMMisslON

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Docket No. 50-320 DCT 29 m3 Metropolitan Edison Company ATTN: Mr. R. C. Arnold, Sr.

Vice President 260 Cherry Hill Road Parsippany, New Jersey 07054 Gentlemen:

The enclosed IE Bulletin 79-17, Revision 1, is forwarded to you for information.

No written response is required.

If you desire additional information regarding this matter, please contact this office.

Sincerely, oyce H. Grier

" Director

Enclosures:

1.

IE Bulletin No. 79-17, Revision 1 w/ Attachment 2.

List of IE Bulletins Issued in the Last Six Months CONTACT:

L. E. Tripp 215-337-5282 cc w/encls:

J. G. Herbein, Vice President Nuclear Operations E. G. Wallace, Manager Licensing G. P. Miller, Manager Support Services and Logistics J. B. Logan, Superintendent Unit 2 G. A. Kunder, Unit 2 Superintendent - Technical Support J. J. Colitz, Manager Plant Engineering R. F. Wilson, Director TMI-2 Recovery, Acting I. R. Finfrock, Jr.

R. W. Conrad G. F. Trowbridge, Esquire J. B. Lieberman, Esquire Ms. Mary V. Southard, Chairperson, Citizens for a Safe Environment 13R6 190 l05 Q

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ENCLOSURE 1 UNITED STATES SSINS No.:

6820 NUCLEAR REGULATORY COMMISSION Accession No.:

OFFICE OF INSPECTION AND ENFORCEMENT 79082201g7 WASHINGTON, D.C.

20555 IE Bulletin No. 79-17 Revision 1 Date:

October 29, 1979 Page 1 of 5 PIPE CRACKS IN STAGNANT BORATED WATER SYSTEMS AT PWR PLANTS Description of Circumstances:

IE Bulletin No. 79-17, issued July 26, 1979, provided information on the R1 cracking experienced to date in safety-related stainless steel piping R1 systems at PWR plants.

Certain actions were required of all PWR R1 facilities with an operating license within a specified 90-day time R1 frame.

After several discussions with licensee owner group representatives and R1 inspection agencies it has been determined that the requirements of Item 2, R1 particularly the ultrasonic examination, may be impractical because of un-R1 availability of qualified personnel in certain cases to complete the in-R1 spections within the time specified by the Bulletin. To alleviate this R1 situation and allow licensees the resources of improved ultrasonic inspec-R1 tion capabilities, a time extension and clarifications to the bulletin have R1 been made.

These are referenced to the affected items of the original R1 bulletin.

During the period of November 1974 to February 1977 a number of cracking incidents have been experienced in safety related stainless steel piping systems and por-tions of systems which contain oxygenated, stagnant or essentially stagnant bor-ated water.

Metallurgical investigations revealed these cracks occurred in the weld heat affected zone of 8-inch to 10-inch type 304 material (schedule 10 and 40), initiating on the piping I.D. surface and propagating in either an inter-granular or transgranular mode typical of Stress Corrosion Cracking.

Analysis indicated the probable corrodents to be chloride and oxygen contamination in the affected systems.

Plants affected up to this time were Arkansas Nuclear Unit 1, R. E. Ginna, H. B. Robinson Unit 2, Crystal River Unit 3, San Onofre Unit 1, and Surry Units 1 and 2.

The NRC issued Circular No. 76-06 (copy attached) in view of the apparent generic nature of the problem.

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During the refueling outage of Three Mi of this year, visual inspections disclo in the spent fuel cooling system piping DUPLICATE DOCUMENT removal system.

These cracks were foun and later confirmed by liquid penetrant Entire document previously cracking was reported to the NRC in a L entered into system under:

1979.

A preliminary metallurgical anal 9

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section of cracked and leaking weld joi ANO

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No. of pages:

R1 - Identifies those additions or revi