ML18229A203
| ML18229A203 | |
| Person / Time | |
|---|---|
| Site: | San Onofre  |
| Issue date: | 08/17/2018 |
| From: | Troy Pruett Division of Nuclear Materials Safety IV |
| To: | Marlone Davis, Eric Simpson, Will Smith Division of Nuclear Materials Safety IV, Region 4 Engineering Branch 1 |
| References | |
| Download: ML18229A203 (5) | |
Text
August 17, 2018 MEMORANDUM TO: Eric J. Simpson, CHP, Health Physicist Fuel Cycle and Decommissioning Branch Division of Nuclear Materials Safety W. Chris Smith, Reactor Inspector Engineering Branch 1 Division of Reactor Safety Marlone X. Davis, Transportation & Storage Safety Inspector Inspections & Operations Branch Division of Spent Fuel Management THROUGH: Janine F. Katanic, PhD, CHP, Chief /RA/ LLH for Fuel Cycle and Decommissioning Branch Division of Nuclear Materials Safety FROM: Troy W. Pruett, Director /RA/
Division of Nuclear Materials Safety
SUBJECT:
INSPECTION CHARTER TO EVALUATE THE NEAR-MISS LOAD DROP EVENT AT SAN ONOFRE NUCLEAR GENERATING STATION A special inspection has been chartered to review the licensees follow-up investigation, causal evaluation, and planned corrective actions regarding the near-miss drop event involving a loaded spent fuel storage canister at the San Onofre Nuclear Generating Station (SONGS) Independent Spent Fuel Storage Installation (ISFSI) on Friday, August 3, 2018.
(License Nos. NPF-10 and NPF-15, Docket Nos. 50-361, 50-362 and 72-41).
CONTACT: Janine F. Katanic, PhD, CHP, FCDB/DNMS (817) 200-1151
E. Simpson 2 BACKGROUND AND BASIS On Friday, August 3, 2018, at approximately 1:30 pm (PST), SONGS was engaged in operations involving movement of a loaded spent fuel storage canister into its underground ISFSI storage vault (HI-STORM UMAX storage system). As the loaded spent fuel canister was being lowered into the storage vault using lifting and rigging equipment, the licensees personnel failed to notice that the canister was misaligned and was not being properly lowered. The licensee continued to lower the rigging and lifting equipment until it believed that the canister had been fully lowered to the bottom of the storage vault. However, a radiation protection technician identified elevated radiation readings that were not consistent with a fully lowered canister. The licensee then identified that the loaded spent fuel canister was hung up on a metal flange near the top of the storage vault, preventing it from being lowered, and that the rigging and lifting equipment was slack and no longer bearing the load of the canister.
In this circumstance, with the important to safety (ITS) rigging and lifting equipment completely down in the lowest position, the ITS equipment was disabled from performing its designed safety function of holding and controlling the loaded canister from a potential canister drop condition. The licensee reported that the canister was resting on a metal flange within the storage vault. It was estimated that the canister could have experienced an approximately 17-18 foot drop into the storage vault if the canister had slipped off the metal flange or if the metal flange failed. This load drop accident is not a condition analyzed in the dry fuel storage systems Final Safety Analysis Report (FSAR).
In response to the discovery that the canister was not fully lowered, the licensee took immediate actions to restore control of the load to the rigging and lifting devices. The estimated time the canister was in an unanalyzed credible drop condition was approximately 45 minutes to 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> in duration. The licensee regained control of the load, repositioned the canister, and lowered the canister into the storage vault. The licensee halted all dry fuel storage movement operations in order to fully investigate the incident and develop corrective actions to prevent a recurrence. In addition, the licensee has shared the operational experience with another site with a similar dry fuel storage system.
Region IV became aware of the SONGS near-miss incident on Monday, August 6, 2018, when the licensee provided a courtesy notification and described it as a near-miss or near-hit event. The reporting requirements of the incident are still being evaluated by the Region and discussed with the licensee.
On August 7 and 16, 2018, Region IV and NMSS representatives participated in conference calls with licensee representatives in order to gather additional facts regarding the circumstances of the incident and the licensees investigation. Region IV is evaluating the information provided by the licensee and is coordinating with the Division of Spent Fuel Management, NMSS.
The NRC is chartering this special inspection pursuant to Management Directive 8.3, NRC Incident Investigation Program, and NRC Inspection Manual Chapter 0309, Reactive Inspection Decision Basis for Reactors.
The purpose of the inspection is to investigate the occurrence; interview personnel; observe equipment; and review relevant documentation, including the results of the licensees investigation and causal analysis, and development and implementation of actions to prevent
E. Simpson 3 recurrence. The licensee has committed to not resume fuel loading operations until after this special inspection and associated reviews are complete. Once the licensee has confirmed its plans to resume fuel loading operations, inspectors will also observe the loading operations to ensure that the corrective actions are adequate. These observations may be conducted as part of this special inspection or as an independent inspection activity, as directed by regional management.
SCOPE The inspection should seek to address the following items at a minimum:
- 1. Identify and review all pertinent records, documents, and procedures related to the licensees downloading operations at the ISFSI pad including but not limited to: worker training and qualifications; rigging equipment qualification, testing, and preventative maintenance; and lifting equipment qualification, testing, and preventative maintenance.
Evaluate the adequacy of the above noted procedures, worker training and equipment testing and preparation.
- 2. Evaluate the adequacy of the loading procedure(s) with respect to verification of MPC movement, centering the MPC over the ISFSI vault, lowering the MPC, and positioning the MPC within the ISFSI vault. Interviews with personnel involved in the ISFSI loading operations should be conducted to evaluate licensee and contractor communications between crane/VCT operators, rigging and spotting staff, cask loading supervisors, radiation protection staff, and licensee oversight personnel. Evaluate the adequacy of pre-job briefings that may have taken place prior to fuel loading operations.
- 3. Review and evaluate the licensees immediate corrective actions taken after the event for adequacy of notifications to the licensee and safety assessments performed immediately following the event. Review the licensees inspection documentation and/or analysis to determine whether the vaults divider shell experienced any damage that would inhibit the component from performing its designed safety function.
- 4. Based on the review of procedures and interviews of personnel involved with loading operations, evaluate the adequacy of procedure adherence.
- 5. Interview personnel associated with the event to develop a timeline to ensure the licensees investigation contained all necessary information to identify all contributing factors and develop adequate corrective actions.
- 6. Review the licensees root cause investigation results, to determine whether the review thoroughly identified all contributing factors and that final corrective actions will be adequate to prevent reoccurrence. Evaluate whether prior operational experience relating to complications or issues associated with canister downloading operations was identified and considered as part of the licensees root cause investigation and corrective action development.
- 7. Review the licensees planned actions that will address the point loading condition that was experienced by the affected canister. If applicable, review the licensees analysis that demonstrated the canister will continue to perform as designed for continued storage OR review licensees inspection plan to safely remove or lift the canister from the vault to support inspection of the bottom of the canister to demonstrate the canister did not
E. Simpson 4 receive any damage that would inhibit the component from continuing to perform as designed.
- 8. Investigate the licensees procedures for reportability to the NRC and determine if the licensee made the correct decision regarding notifications made to the NRC for this event.
- 9. As directed by regional management, observe resumption of fuel loading operations to verify that corrective actions were effective in addressing deficiencies that contributed to the event. This should include evaluation of procedure and/or equipment enhancements; review or observation of training and briefings provided to riggers, crane operators, spotters and observers, supervisors and other personnel involved in fuel loading operations.
- 10. Determine if the inspection should be elevated to an AIT and promptly notify regional management of any recommendation to escalate the special inspection to an AIT.
GUIDANCE The NRC is chartering this special inspection pursuant to Management Directive 8.3, NRC Incident Investigation Program, and NRC Manual Chapter 0309, Reactive Inspection Decision Basis for Reactors. The Manual Chapter and Management Directive identify Inspection Procedure 93812, Special Inspection, for specific use in reviewing events. Planned Dates of Inspection are September 10-14, 2018.
This inspection should emphasize fact-finding in its review of the circumstances surrounding the near-miss canister drop event. Safety concerns identified that are not directly related to near-miss drop event should be reported to NRC management for appropriate action.
Daily briefings with NRC management should occur to discuss the teams progress and preliminary observations.
In accordance with Manual Chapter 0610, a report documenting the results of the inspection should be issued within 30-45 days of the completion of the inspection.
This Charter may be modified should NRC inspectors find significant new information that warrants review. Should you have any questions concerning this charter, please contact Janine F. Katanic at 817-200-1151.
INSPECTION CHARTER TO EVALUATE THE NEAR-MISS LOAD DROP EVENT AT SAN ONOFRE NUCLEAR GENERATING STATION - DATED AUGUST 17, 2018 DISTRIBUTION:
KKennedy, ORA SMorris, ORA TPruett, DNMS LHowell, DNMS JKatanic, DNMS LBrookhart, DNMS MLayton, NMSS ARivera-Varona, NMSS VDricks, ORA BMaier, ORA CLipa, DNMS/RIII JTrapp, DNMS/RI TInverso, OEDO AMoreno, OCA JWeil, OCA ADAMS ACCESSION NUMBER: ML18229A203 SUNSI Review ADAMS: Non-Publicly Available Non-Sensitive Keyword:
By: LLH Yes No Publicly Available Sensitive NRC-002 OFFICE DNMS:FCDB DNMS:DD DNMS:D NAME JFKatanic LLHowell TWPruett SIGNATURE /RA/ LLH for /RA/ /RA/
DATE 8/17/18 8/17/18 8/17/18 OFFICAL RECORD COPY