Bulletin 78-12B: Atypical Weld Material in Reactor Pressure Vessel Welds

                               UNITED STATES 
                       NUCLEAR REGULATORY COMMISSION 
                    OFFICE OF INSPECTION AND ENFORCEMENT 
                           WASHINGTON, D.C. 20555 
                                     
                               March 19, 1979

                                                    IE Bulletin No. 78-12B 

ATYPICAL WELD MATERIAL IN REACTOR PRESSURE VESSEL WELDS 

Description of Circumstances: 

This Bulletin is a supplement to IE Bulletins 78-12 and 12A and all three 
documents must be collectively considered to provide an adequate response to
the bulletins. 

Following the issuance of IE Bulletin 78-12A, members of the Office of 
Inspection and Enforcement staff met with representatives from the reactor 
vessel manufacturers and suppliers to discuss the requirements of the 
bulletins.  During these meetings, detailed interpretation of the data 
requirements was provided based on the manufacturer's respective methods of 
fabrication and record systems. 

Recognizing that the scope of the record review is extensive, additional 
time to respond to the bulletins is provided by this supplement. 

Action to be Taken by Licensees and Permit Holders: 

This bulletin applies to all power reactor facilities with an operating 
license or a construction permit, except those already identified as 
possibly having atypical weld material. 

Responses to the requirements in Bulletins 78-12 and 12A shall be submitted 
in writing in accordance with the following schedule: 

1.   Generic reports from each reactor vessel manufacturer shall be 
     submitted to the NRC by May 1, 1979. 

2.   The licensee responses shall be submitted by May 29, 1979. The 
     licensee's response shall include all of the specific vessel 
     information required by the bulletins which is not covered by the 
     vessel manufacturers generic report and shall indicate that the 
     licensee is satisfied that the generic report adequately represents 
     data for the specific vessels covered by the licensee's report. 

Approved by GAO, B180225 (R0072); clearance expires 7/31/80. Approval was 
given under a blanket clearance specifically for identified generic 
problems. 



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