Technical Specification 3.5.3,
Emergency Core Cooling System (
ECCS) Shutdown, requires, in part, that in Mode 4 one
emergency core cooling system train shall be
operable. The
operable emergency core cooling system train must provide a flow path from the refueling water storage tank to the
reactor coolant system via each of the four cold leg injection nozzles. Contrary to the above, on January 22, 2010, Callaway Plant identified that Procedure OTO-BB-00010, Shutdown
LOCA, did not instruct operators to align the
residual heat removal cross-tie valves to supply
emergency core cooling system flow to each of the four
reactor coolant system cold leg injection nozzles. This finding was entered in the licensees corrective action program as Callaway Action Request 201000601. This finding is greater than minor because it was associated with the procedural quality attribute of the
Mitigating Systems Cornerstone and adversely affected the cornerstone objective to ensure the availability, reliability, and capability of systems that respond to
initiating events to prevent undesirable consequences. The inspectors performed the initial significance determination for the failure to translate technical specification requirements into operating procedures using NRC Inspection Manual 0609, Attachment 0609.04, Phase 1 Initial Screening and Characterization of Findings. The finding screened to a Phase 2 significance determination, using NRC Inspection Manual 0609, Appendix G, Shutdown Operations Significance Determination, because the finding affected the licensees ability to add
reactor coolant system inventory when needed. A Region IV senior reactor analyst performed a Phase 2 significance determination using Inspection Manual 0609, Appendix G. In this particular case, the finding only involved the failure to align all four injection pathways to the discharge of the
residual heat removal pump that was aligned for coolant injection. Two pathways were still available. This alignment, while not consistent with technical specification requirements, was adequate to meet the probabilistic safety function in the
significance determination process. Consequently, there was no quantifiable change in risk using the
significance determination process worksheets. The applicable worksheets included those for loss of inventory and loss of level control. Therefore, the finding was of very low safety significance.
