An unresolved item (
URI) was identified related to the Unit 1 failure of PT/1/A/0400/020, SSF
Reactor Coolant (RC) Letdown Line Discharge Test. The licensee conducted PT/1/A/0400/020 with Unit 1 at approximately 280psig to verify an acceptable flow rate could be established through the SSF letdown line. No flow was evident based on pressurizer level remaining constant throughout the duration of the test. The licensee determined that foreign material was blocking a filter installed on the inlet side of a flow orifice in the letdown line. The majority of this foreign material was determined to be Grafoil
gasket material from the
backseat gasket of a valve upstream of the filter. Because the test was performed at a lower pressure than normal operating pressure, the licensee will conduct additional testing to determine if the SSF RC letdown line would have performed its safety function at normal operating pressure. The results of this test will be reviewed to determine if the SSF letdown line was capable of performing its design function. This is identified as
URI 05000269,/2009005-002.
