ML19210C523
| ML19210C523 | |
| Person / Time | |
|---|---|
| Site: | Peach Bottom  |
| Issue date: | 10/29/1979 |
| From: | Grier B NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I) |
| To: | Daltroff S PECO ENERGY CO., (FORMERLY PHILADELPHIA ELECTRIC |
| References | |
| NUDOCS 7911150070 | |
| Download: ML19210C523 (1) | |
Text
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,o, UNITED STATES y } >% (,g
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NUCLEAR REGULATORY COMMISSION I;
/.. 5 REGION I G f'iOJ1 3 ; J/
8 631 PARK AVENUE
,o KING OF PRUSSIA, PENNSYLVANIA 19406 Docket Nos. 50-277 50-278 Ocy 2 g,3 gg Philadelphia Electric Company ATTN:
Mr. S. L. Daltroff Vice President Electric Production 2301 Market Street Philadelphia, Pennsylvania 19101 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, f
Y
,ML 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:
W. T. Ullrich, Station Superintendent Troy B. Conner, Jr., Esquire Eugene J. Bradley, Esquire Raymond L. Hovis, Esquire Michael J. Scibinico, II, Assistant Attorney General 1332 A7 79111500 70
ENCLOSURE 1 UNITED STATES SSINS No.:
6820 NUCLEAR REGULATORY COMMISSION Accession No.:
OFFICE OF INSPECTION AND ENFORCEMENT 7908220157 I3 7 WASHINGTON, D.C.
20555 IE Bulletin No. 79-17 Revision 1 Date:
October 29, 1979 Page 1 of 5 PIPE CRACKS IN STAGNANT B0 RATED 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 pir.,ing 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 or" ~,a1 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 prcbable 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.
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 Enthe document previously cracking was reported to the NRC in a L entered into system under-1979.
A preliminary metallurgical anal pgypg/
section of cracked and leaking weld J01_
gg 332
- 58 R1 - Identifies those additions or revi g
N o. or geyes,