A self-revealing non-cited violation of
TS 5.4, Procedures, was identified when the licensed control room operator failed to perform step 4.3.5.10.b of procedure 3010-1,
Boron Thermal Regeneration System, Rev 57. Failure to properly perform this step resulted in approximately 500 gallons of unborated water being added to the
VCT causing an inadvertent positive reactivity addition to the Unit 1 reactor. The failure to place handswitch 1-HS-7054 in the CLOSED position as required by procedure is a performance deficiency. The minor screening criteria in
IMC 0612, Power Reactor Inspection Reports, Appendix B, was not used due to the lack of clear guidance regarding inadvertent reactivity additions. Therefore, in consultation with the
NRR program office, regional management determined this finding is more than minor because the licensed operator failed to properly implement procedure 13010-C which resulted an inadvertent positive reactivity addition causing reactor power to briefly increase above 100%. The finding, assessed using the
Significance Determination Process, was determined to be of very low safety significance (Green) because the resulting
transient did not contribute to both the likelihood of a
reactor trip and the likelihood that mitigation equipment or functions would not be available. The inspectors determined this finding was related to the Work Practices component of the Human Performance cross-cutting area in that the licensed operator did not have the procedure in-hand during use as required by procedure 00054-C, Rules for Performing Procedures, Rev. 19.
H.4(b) (Section 4OA3
