The following violation of very low significance (Green) was identified by the licensee and is a violation of NRC requirements which meets the criteria of the
NRC Enforcement policy for being dispositioned as an
NCV. Clinton
TS 3.9.4,
Control Rod Position Indication, required one
control rod full-in position indication channel for each
control rod shall be
operable in Mode 5. If one or more required
control rod position indication channels is
inoperable then suspend in-vessel fuel movement, suspend
control rod withdrawal and initiate action to fully insert all insertable
control rods in core cells containing one or more fuel assemblies or initiate action to fully insert the
control rod associated with the
inoperable position indicator and initiate action to disarm the
control rod drive associated with the fully inserted
control rod. These actions are to be performed immediately if a
control rod position indication becomes
inoperable. Contrary to the above, on April 30, 2015,
control rod 3237 had a position indication probe simulator installed to simulate a fullin position to support generic position indication probe replacements, which did not provide actual position indication, making the
control rod inoperable while in-vessel fuel movement was occurring and action to disarm the
control rod drive associated with the fully inserted
control rod had not been completed for a period of approximately
7 hours8.101852e-5 days <br />0.00194 hours <br />1.157407e-5 weeks <br />2.6635e-6 months <br />. This exceeded the TS allowed outage time for the limited conditions for operation with a
control rod position indication
inoperable. The licensee identified the condition during log reviews between shifts and took actions to suspend fuel movement and to disarm the associated
control rod drive immediately after the
time of discovery. Additionally the licensee entered the issue into the
CAP as
AR 02494024. The issue was determined to be more than minor because the performance deficiency, if left uncorrected, could be reasonably viewed as a precursor to a more significant event. The finding was screened under
IMC 0609 Appendix G, Attachment 1, Shutdown Operations
Significance Determination Process, Exhibit 2,
Initiating Events Screening Questions, as having very low safety significance (Green) because it did not increase the likelihood of a shutdown initiating event or increase the likelihood of a fire or external/internal flood that could cause an shutdown initiating event.
