ML19290B788
| ML19290B788 | |
| Person / Time | |
|---|---|
| Site: | Arkansas Nuclear  |
| Issue date: | 10/29/1979 |
| From: | Seyfrit K NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION IV) |
| To: | Cavanaugh W ARKANSAS POWER & LIGHT CO. |
| References | |
| NUDOCS 7912140103 | |
| Download: ML19290B788 (1) | |
Text
CENTRAL FILES PDR:HQ UNITED STATES
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/(ta "E coq'o NUCLEAR REGULATORY COrv1 MISSION pfL aEcion iv NSIC y.m
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\\..... *er October 29, 1979 Docket Nos.
50-313 50-368 Arkansas Power and Light Company ATTN:
Mr. William Cavanaugh III Vice I rcsident of Generation and Construction P. O. Box 551 Little Rock, Arkansas 72203 Gentlemen:
The enclosed IE Bulletin No. 79-17, Revision 1 is forwarded to you for action. A written response is required.
If you desire additional information regarding this matter, please contact this office.
Sincerely, i
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'A ftt/TU1 Karl V. Seyfrit-Director
Enclosures:
1.
IE Bulletin No. 79-17, Revision 1 2.
List of IE Bulletins Issued in Last Six Months cc: James P. O'llanlon, Plant Manager Arkansas Nuclear One P. O. Box 608 Russellville, Arkansas 72801 1574 559 I
7912140
UNITED STATES SSINS No.: 6820 NUCLEAR REGULATORY COMMISSION Accession No.:
OFFICE OF INSPECTION AND ENFORCEMENT 7908220157 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 cracking R1 experienced to date in safety-related stainless steel piping systems at PWR R1 plants. Certain actions were required of all PWR facilities with an operating R1 license within a specified 90-day time frame.
R1 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 R1 unavailability of qualified personnel in certain cases to complete the R1 inspections within the time specified by the Bulletin. To alleviate this R1 situation and allow licensees the resources of improved ultrasonic inspection R1 capabilities, a time extension and clarifications to the bulletin have been R1 made. These are referenced to the affected items of the original 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 enclosed) in view of the apparent generic nature of the problem.
During the refueling outage of Three Mile Island Unit I which began in February of this year, visual inspections disclosed five (5) through-wall cracks at welds in the spent fuel cooling system piping and one (1) at a weld in the decay heat removal system. These cracks were found as a result and later confirmed by liquid penetran cracking was reported to the NRC in a 1979. A preliminary metallurgical ana DUPLICATE DOCUMENT i574 360 section of cracked and leaking weld jo Entire document previously entered into system under:
R1 - Identifies those additions or revi ANO N o.
of pages:
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