ML19246B165
| ML19246B165 | |
| Person / Time | |
|---|---|
| Site: | Yankee Rowe |
| Issue date: | 06/25/1979 |
| From: | Grier B NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I) |
| To: | Groce R YANKEE ATOMIC ELECTRIC CO. |
| References | |
| NUDOCS 7907120585 | |
| Download: ML19246B165 (1) | |
Text
4 f.pR R g
-f&,
/
g%
UNITED STATES
[ y,", 'j[',h NUCLEAR REGULATORY COMMISSION 3-s REGION I 0, - k
,[
631 PARK AVENUE h,
,o' KING OF PRUSSIA, PENNSYLVANIA 19406 June 25, 1979 Docket No. 50-29 Yankee Atomic Electric Company ATTN:
Mr. Robert H. Grace Licensing Engineer 20 Turnpike Road Westborough, Massachusetts 01581 Gentlemen:
Enclosed is IE Bulletin No. 79-13 which requires action by you vith regard to your power reactor facility (ies) with an operating license.
Should you have any qastions regarding this Bulletin or the actions required by you, please contact this office.
Sincerely, Vf.
kw 8'
H. Grier irector
Enclosures:
1.
IE Bulletin No. 79-13 w/ Attachments 2.
List of IE ~411etins Issued in Last Twelve Months cc v/encls:
H. Autio, Plant Superintendent L. E. Minnick, President m
342 2bb k 2 0 5M,'
700
ENCLOSURE 1 UNITED STATES NUCLEAR REGULATORY C0ftfiISSION OFFICE OF INSPECTION AND EtiFORCEf TENT WASHINGTON, D.C.
20555 IE Bulletin No. 79-13 Date: June 25, 1979 Page 1 of 4 CRACKING IN FEEDWATER SYSTEM PIPING Description of Circumstances:
On flay 20, 1979, Indiana and flichigan Power Compcny notified the NRC of cracking in two feedwater lines at their D. C. Cook Unit 2 facility.
The cracking was discovered following a shutdown on 'iay 19 to invest.igate ledage inside containment.
Leaking circumferential cracks were identified in the 16-inch feedwater elbows adjacent to two steam generator nozzle elbow weids.
Subsequent radiographic examination revealed crack indications in all eight steam generator feedwater lines at this location on both Units 1 and 2.
On fiay 25, 1979, a letter was sent to all PWR licensees by the Office of fluclear Reactor Regulation which informed licensees of the D. C. Cook failures and requested specific information on feedwater system design, fabrication, inspection and operating histories.
To further explore the generic nature of
'he cracking problem, the Office of Inspection and Enforcement requested licensees of PWR plants in current outages to immediately conduct volumetric examination of certain feedwater piping welds.
As a result of these actions, several other licensees with Westinghouse steam generators reported crack indications.
Southern California Edison reported on June 5,1979, that radiographic examination revealed indications of cracking in feedwater nozzle-to-piping welds on two of three steam generators of San Onofre Unit 1.
On June 15, 1979, Carolina Power and Light reported that radiography showed crack indications in similar locations at their H. B. Robinson Unit 2.
Duquesne Power and Light confirmed on June 18, 1979, that radiography has shown cracking in their Beaver Valley Unit 1 feedwater piping to vessel nozzle weld.
Public Service Electric and Gas Ccmpany reported on June 20, 1979 that Salem Unit 1 also has crack indications.
Misconsin Public Service company decided on June 20, 1979 to cut out a feedwater nozzle-to-pipe weld which c.mMined questionable indication, for metallurgical examination.
As of June 22,1979 and since May 15, 1979 seven other PUP. facilities have inspected the feedwater nozzle-to-pipe welds without finding cracking indications.
The feedwater nozzle-to-pipe configurations for D.C. Cook and for San nnnfra weld joint detail showing the prin
- a rp,i shown on the attached figures 1 art ~ " "
'T~
are shown on the attached figure 3 DUPLICATE DOCUMENT e
On March 17, 1977, during heat-up Entire document previously entered
>a Unit 1, a leak was discovered in t into system under:
the 16-inch diameter feedwater pip.
b nondestructive examination of all ANO 4
No. of pages:
//
3l} 2 2hh g
m-
- a