On April 25, 2008,
DC Cook Unit 1 was in Mode 4 heating up the
RCS after a refueling outage. Personnel were performing a containment walkdown, with the
RCS at 1000 psig, looking for leakage. Wisps of steam were seen coming from a 3/4 inch
RCS flow instrument line weld, between the
RCS loop piping and the instrument isolation valve. The leakage is less than 0.1 gpm. The leakage can not be isolated from the
RCS and has been declared to be
RCS Pressure Boundary Leakage. Entry into the
RCS Operational Leakage
Technical Specification, 3.4.13, was made at 2210 on April 25, 2008. This Technical Specification requires being in Mode 5 within
36 hours4.166667e-4 days <br />0.01 hours <br />5.952381e-5 weeks <br />1.3698e-5 months <br />.
The plant is cooling down and depressurizing as required by Technical Specifications.
The plant is currently evaluating the appropriate repair method for this condition.
The licensee notified the NRC Resident Inspector.
