ML18312A118
| ML18312A118 | |
| Person / Time | |
|---|---|
| Site: | San Onofre  |
| Issue date: | 11/08/2018 |
| From: | NRC Region 4 |
| To: | |
| References | |
| Download: ML18312A118 (32) | |
Text
San Onofre Special Inspection Webinar November 8, 2018 NRC Region IV, Arlington, TX
~us.NRC United States Nuclear Regulatory Commission Protecting People and the Environnient
Logistics
- Webinar Format
- Back-up Bridge Line (888) 469-1677, Passcode 2471451
- Questions and Answers 2
US.NRC United States Nuclear Regulatory Commission Protecting People and the Environment
NRC Staff
- Eric Simpson, Special Inspection Team Leader Region IV Fuel Cycle and Decommissioning Branch
- Patricia Silva, Branch Chief Division of Spent Fuel Management
- Troy Pruett, Director Region IV Division of Nuclear Materials Safety 3
US.NRC United States Nuclear Regulatory Commission Protecting People and the Environment
Webinar Agenda
- Background
- Canister Downloading Operations
- Inspection Team Findings
- Current Status
- Summary
- Questions & Answers 4
US.NRC United States Nuclear Regulatory Commission Protecting People and the Environment
ISFSI Layout 5
TN NUHOMS Design Holtec UMAX Design
Transnuclear NUHOMS 6
Holtec UMAX 7
Vertically Ventilated Module (Vault) 8
Spent Fuel Canister 9
Holtec MPC Transfer Cask
Downloading: Shield Cone 10
Downloading: Transporter 11
Downloading: Vault Door 12
Downloading:
Alignment 13
Downloading:
Attaching Slings 14
Downloading:
Attaching Slings 15
Downloading Preparations 16
17 What Happened on August 3rd?
Low Dose Area Low Dose Area
What Happened on August 3rd?
18
What Happened on August 3rd?
19
What Happened on August 3rd?
20
21 What Happened on August 3rd?
Post Event Actions
- Spent Fuel Handling Activities Suspended
- NRC Inspection Activities
- San Onofre Notification to NRC
- Causal Evaluations
- Corrective Actions 22 US.NRC United States Nuclear Regulatory Commission Protecting People and the Environment
Spent Fuel Handling Activities Suspended 23
- MPC 29 lowered into vault
- San Onofre suspends fuel loading
- MPC 30
- Inside Transfer Cask
- Seismically Restrained in Fuel Building US.NRC United States Nuclear Regulatory Commission Protecting People and the Environment
NRC Inspection Activities 24
- August 6th: NRC Region IV informally notified of Misalignment Event and initiates daily oversight communications
- August 7th: San Onofre commits to NRC review before resuming operations
- August 17th: NRC decides to conduct Special Inspection
- September 10-14: NRC Special Inspection Team onsite
- NRC to perform inspection prior to resumption of fuel loading US.NRC United States Nuclear Regulatory Commission Protecting People and the Environment
NRC Inspection Activities 25
- 2 Preliminary Escalated Findings
- Failure to provide redundant drop protection
- Failure to report
- 3 Preliminary Severity Level IV Violations
- Procedures
- Corrective actions
- Training
- Management Oversight Weaknesses US.NRC United States Nuclear Regulatory Commission Protecting People and the Environment
Causal Evaluations 26
- San Onofre Apparent Cause Evaluation
- Holtec Root Cause Analysis
- Common Cause Evaluation US.NRC United States Nuclear Regulatory Commission Protecting People and the Environment
Root Causes
- San Onofre Management failed to provide
- Adequate procedures
- Adequate training to support procedure
- Adequate oversight 27 US.NRC United States Nuclear Regulatory Commission Protecting People and the Environment
Corrective Actions
- Training Requirements
- Procedure Enhancements
- Equipment Enhancements
- Oversight Improvements 28 US.NRC United States Nuclear Regulatory Commission Protecting People and the Environment
Event Significance
- No Actual Drop of Canister
- No Radiological Release
- Load Drop Analysis (if canister fell) 29 US.NRC United States Nuclear Regulatory Commission Protecting People and the Environment
Next Steps
- Issue NRC Inspection Report
- NRC Inspection of Causal Analyses
- NRC Inspection of Corrective Actions 30 US.NRC United States Nuclear Regulatory Commission Protecting People and the Environment
Summary
- Could have been prevented
- Weaknesses in management oversight
- Multiple failed barriers
- Increased NRC oversight 31 US.NRC United States Nuclear Regulatory Commission Protecting People and the Environment
Questions 32