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A finding of very low safety significance … A finding of very low safety significance with an associated NCV of Technical Specification (TS) 5.4, Procedures, was self-revealed when a valid automatic reactor scram signal and isolation signal for multiple primary containment isolation valves was actuated. A reactor operator, who was maintaining RPV water level and reactor pressure following a plant scram, did not initiate reactor core isolation cooling (RCIC) system flow in time to maintain level above the Level 3 reactor protection system actuation setpoint. As an immediate corrective action, control room operators promptly restored RPV level by manual operation of the RCIC system. The licensee entered this issue into the corrective action program and provided remedial training for the reactor operator in the simulator, communicated lessons learned from this event with other licensed operators, and subsequently implemented improvements for licensed operator training and procedure changes to incorporate a revised strategy for manual control of RPV level and pressure control with main steam line isolation valves closed. The performance deficiency was of more than minor safety significance because it was associated with the Human Performance attribute of the Initiating Events cornerstone and adversely affected the cornerstone objective of limiting the likelihood of events that upset plant stability and challenge critical safety functions during shutdown as well as power operations. Specifically, the human performance error unnecessarily challenged a plant protection feature, which resulted in a valid automatic reactor scram signal and isolation signal for multiple primary containment isolation valves. In addition, the finding was sufficiently similar to Example 4(b) in IMC 0612, "Power Reactor Inspection Reports," Appendix E, "Examples of Minor Issues," for not of minor safety significance since the error resulted in a valid automatic reactor scram signal and isolation signal for multiple primary containment isolation valves. The finding was determined to be of very low safety significance since it did not cause a reactor scram and a loss of mitigation equipment relied upon to transition the plant to a stable shutdown condition (e.g., loss of condenser, loss of feedwater). The inspectors concluded this finding affected the cross-cutting aspect of resources in the human performance area. Specifically, the licensees evaluation identified the reactor operator had been performing a complicated task for a long period of time without adequate rest/recovery periods (IMC 0310, H.1).ate rest/recovery periods (IMC 0310, H.1).

Discovered date

23:59:59, 31 March 2016 +

Docket

05000341 +

Event date

23:59:59, 31 March 2016 +

Finding integer

9 +

Finding type

Non-cited violation +

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INPO aspect

LA.1 +

Identified by

Self-revealing +

Inspection Manual Chapter

NRC Inspection Manual 0612, Power Reactor Inspection Reports +

Inspection procedure

IP 71153, Event Followup +

Inspection report

IR 05000341/2016001 +

Inspector

Billy Dickson +, Brian Kemker +, Phillip Smagacz + and Jim Nance +

Modification date"Modification date" is a predefined property that corresponds to the date of the last modification of a subject and is provided by <a rel="nofollow" class="external text" href="https://www.semantic-mediawiki.org/wiki/Help:Special_properties">Semantic MediaWiki</a>.

12:56:16, 25 September 2017 +

Person

Billy Dickson +, Brian Kemker +, Phillip Smagacz + and Jim Nance +

2016Q1 +

Green +

Fermi +