A licensee-identified violation was discovered on March 2, 2012, of Unit 1
TS 3.9.4, which states that
control rod full-in position indication channel for each
control rod shall be
operable during mode 5. Contrary to this requirement, from February 28 until March 2, 2012, the full-in indication for
CRB 22-27 was
inoperable with a modified probe buffer card installed to bypass the full-in indication signal in order to remove the rod block. On February 28 licensee personnel inadvertently cleared (i.e., removed) a tag-out for CRB22-27 without removing the modified probe buffer card and without performing a functional test of the full-in indication prior to moving fuel in the reactor vessel. Fuel movement occurred from the time the tag-out was removed until 0817 EST on March 2 when the error was discovered. The inspectors screened the significance of this violation using
IMC 0609 Appendix G, Shutdown Operations
Significance Determination Process. The finding did not screen as requiring a Phase 2 or Phase 3 review per
IMC 0609 Appendix G, therefore this finding screened as having very low risk significance (Green). Corrective actions taken by the licensee included immediately disabling
CRB 22-27 to comply with
TS 3.9.4 and enhancements to strengthen administrative controls on processes relied upon to comply with TS. This issue was entered in the licensees corrective action program as CR 417608 and was documented in
LER 05000321/2012-001.
