Title 10 of the Code of Federal Regulations, Part 50, Appendix B, Criterion IX, Control of Special Processes, requires that, Measures shall be established to ensure that special processes, including welding, heat treating, and nondestructive testing, are controlled and accomplished by qualified personnel using qualified procedures in accordance with applicable codes, standards, specifications, criteria, and other special requirements. Contrary to the above, during original construction in 1974, the licensee failed to ensur
that a welding process was performed in accordance with the applicable America
Society of Mechanical Engineers (ASME) Code requirements. Small bore piping weld
connecting vent and drain valves to safety injection pumps were completed according t
a welding procedure specification (WPS) that was written for welding carbon steel t
stainless steel. The actual welds connected stainless steel components; therefore, th
WPS used did not meet ASME B31.7 (Nuclear Power Piping) and ASME Section I
(Welding, Brazing, and Fusing Qualifications) requirements. Failure to comply wit
ASME Code welding requirements could result in flaws within safety injection syste
piping welds. This performance deficiency was more than minor because it wa
associated with the mitigating systems cornerstone attribute of design control an
adversely affected the cornerstone objective of ensuring the availability, reliability, an
capability of systems that respond to initiating events. The safety significance of thi
issue was considered very low (Green) because it did not result in a loss of operability o
functionality of the safety injection system. The as-built welds were evaluated to hav
adequate material properties and were determined not to contain flaws and, therefore
did not affect safety injection system operability. This issue was documented in th
licensees corrective action program as Notification Report 50600119.
