Crystal River - a loud noise was heard from the fuel hoist while withdrawing a fuel assembly from the reactor core

* During core off-load work, a loud noise was heard from the fuel hoist while withdrawing a fuel assembly from the reactor core ...

The inspectors selected condition report (CR) 467392 for a more in-depth review of the circumstances surrounding and decisions made after a malfunction of the fuel handling crane (FHCR-1) fuel hoist. On May 22, 2011, while performing core off-load activities, a loud noise was heard from the FHCR-1 fuel hoist while withdrawing a fuel assembly from the reactor core. After some discussion and initial troubleshooting activities, the fuel assembly was left suspended approximately 3 feet above the core plate. A temporary cable restraint system was installed on May 24, 2011, and the licensee subsequently secured the refueling senior reactor operator (SRO) position believing they were no longer in a core alteration. Several hours later, after determining that the suspended fuel assembly was considered to be a core alteration, the licensee re-stationed an SRO at FHCR-1.

CR 467392 was initially classified as significance level two requiring an apparent cause evaluation, but was later reclassified as significance level one requiring a root cause evaluation. The root cause evaluation focused on the leadership behaviors and decisions made surrounding the event. The inspectors checked that the issues had been completely and accurately identified in the licensee's corrective action program; safety concerns were properly classified and prioritized for resolution; the root cause evaluation was sufficiently thorough; and appropriate corrective actions were initiated. The inspectors also evaluated the CR using the requirements of the licensee's CAP as delineated in corrective action procedure CAP-NGGC-0200, Condition Identification and Screening Process. Additional documents reviewed are listed in the attachment.

No NRC-identified or self-revealing findings were identified; however, the inspectors had several observations. The inspectors concurred with the licensee's conclusions that the refueling procedures did not provide sufficient guidance when it came to consulting departments outside of the refueling team when equipment issues arose. The procedures gave the refueling supervisor broad authority to make troubleshooting decisions without consulting management or licensing. This is of particular concern because malfunctions of fuel handling equipment could potentially result in fuel damage or cause the licensee to be in violation of regulations.

The refueling SRO did not initially notify the shift manager or others outside of the refueling team prior to allowing the refueling contractor to perform initial troubleshooting activities on FHCR-1. Considering the damage identified during inspection of the gear box after the event, it is possible that additional troubleshooting activities could have resulted in a dropped fuel assembly. The refueling procedures in place at the time allowed the refueling SRO to make the decision to troubleshoot without consulting outside departments. Another issue the inspectors observed was that site licensing was not informed of the decision to secure the refueling SRO until several hours after the decision was made. If licensing had been consulted early on, the decision to secure the refueling SRO may not have occurred. The inspectors verified that the licensee initiated the appropriate corrective actions to prevent recurrence of this issue or similar issues.

The inspectors noted that the root cause evaluation of this incident was not completed until October 10, 2011, almost five months after the incident occurred. The licensee initiated CR 487174 which addressed, in part, the role that leadership behaviors played in the delayed completion of the FHCR-1 root cause evaluation. This delay did not affect the safety significance of the condition since immediate actions were taken to station the refueling SRO, repair the failed crane components, and secure and lower the fuel assembly.

The inspectors determined that the licensee's decision to secure the refueling SRO position while the fuel assembly was suspended (core alteration) was a performance deficiency. The finding was determined to be of greater than minor significance because it affected the barrier integrity cornerstone objective to provide reasonable assurance that physical barriers protect the public from radionuclide releases caused by accidents or events. Specifically, leaving the suspended fuel assembly unsupervised, even though secured by a temporary cable restraint system, would reduce the level of assurance that fuel damage would be prevented. The licensee re-stationed an SRO at FHCR-1 once it was determined that the suspended fuel assembly was considered to be a core alteration. A licensee identified violation of Improved Technical Specification 5.6.1.1a was assessed by the inspectors and is documented in Section 4OA7 of this inspection report.

The following violation of very low safety significance (Green) was identified by the licensee and was a violation of NRC requirements which met the criteria of the NRC Enforcement Policy for being dispositioned as a Non-Cited Violation:

* Improved Technical Specification 5.6.1.1a requires that written procedures recommended in Regulatory Guide (RG) 1.33, Revision 2, Appendix A, be established, implemented, and maintained. RG 1.33, Appendix A, includes general operating procedures for Refueling & Core Alterations in the list of recommended procedures. Plant Operating Manual FP-601A, Operation of the Main Fuel Handling Bridge FHCR-1, Section 3.2.22, requires, in part, that a refueling SRO be stationed during a core alteration. Contrary to this requirement, the licensee secured the refueling SRO during activities determined to be a core alteration for approximately seven-hours on May 24, 2011. The licensee entered this issue into their CAP as CR 467392. The significance of the finding was determined using Manual Chapter 0609, "Significance Determination Process", Appendix G, Checklist 4 (PWR Refueling Operation, RCS level > 23 ft) and determined to be of very low safety significance (Green), because it did not cause the loss of mitigating capability of core heat removal, inventory control, power availability, containment control, or reactivity control. Additional information regarding this NCV is discussed in Section 4OA2 of this inspection report.

[Source: NRC Region II inspection report 05000302/2011005 ML120230101, pp. 19-20, 21-22

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