ML18312A118

Presentation for San Onofre Special Inspection Webinar November 8, 2018

ML18312A118
Person / Time
Site:	San Onofre
Issue date:	11/08/2018
From:	NRC Region 4
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Download: ML18312A118 (32)

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~us.NRC United States Nuclear Regulatory Commission Protecting People and the Environnient San Onofre Special Inspection Webinar November 8, 2018 NRC Region IV, Arlington, TX

US.NRC Logistics United States Nuclear Regulatory Commission Protecting People and the Environment

• Webinar Format

• Back-up Bridge Line (888) 469-1677, Passcode 2471451

• Questions and Answers 2

US.NRC NRC Staff United States Nuclear Regulatory Commission Protecting People and the Environment

• 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 Webinar Agenda United States Nuclear Regulatory Commission Protecting People and the Environment

• Background

• Canister Downloading Operations

• Inspection Team Findings

• Current Status

• Summary

• Questions & Answers 4

ISFSI Layout TN NUHOMS Design Holtec UMAX Design 5

Transnuclear NUHOMS 6

Holtec UMAX 7

Vertically Ventilated Module (Vault) 8

Spent Fuel Canister Holtec MPC Transfer Cask 9

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

What Happened on August 3rd?

Low Dose Area Low Dose Area 17

What Happened on August 3rd?

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What Happened on August 3rd?

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What Happened on August 3rd?

20

What Happened on August 3rd?

21

US.NRC Post Event Actions United States Nuclear Regulatory Commission Protecting People and the Environment

• Spent Fuel Handling Activities Suspended

• NRC Inspection Activities

• San Onofre Notification to NRC

• Causal Evaluations

• Corrective Actions 22

US.NRC Spent Fuel Handling Activities Suspended United States Nuclear Regulatory Commission Protecting People and the Environment

• MPC 29 lowered into vault

• San Onofre suspends fuel loading

• MPC 30

- Inside Transfer Cask

- Seismically Restrained in Fuel Building 23

US.NRC NRC Inspection Activities United States Nuclear Regulatory Commission Protecting People and the Environment

• 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 24

US.NRC NRC Inspection Activities United States Nuclear Regulatory Commission Protecting People and the Environment

• 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 25

US.NRC Causal Evaluations United States Nuclear Regulatory Commission Protecting People and the Environment

• San Onofre Apparent Cause Evaluation

• Holtec Root Cause Analysis

• Common Cause Evaluation 26

US.NRC Root Causes United States Nuclear Regulatory Commission Protecting People and the Environment

• San Onofre Management failed to provide

- Adequate procedures

- Adequate training to support procedure

- Adequate oversight 27

US.NRC Corrective Actions United States Nuclear Regulatory Commission Protecting People and the Environment

• Training Requirements

• Procedure Enhancements

• Equipment Enhancements

• Oversight Improvements 28

US.NRC Event Significance United States Nuclear Regulatory Commission Protecting People and the Environment

• No Actual Drop of Canister

• No Radiological Release

• Load Drop Analysis (if canister fell) 29

US.NRC Next Steps United States Nuclear Regulatory Commission Protecting People and the Environment

• Issue NRC Inspection Report

• NRC Inspection of Causal Analyses

• NRC Inspection of Corrective Actions 30

US.NRC Summary United States Nuclear Regulatory Commission Protecting People and the Environment

• Could have been prevented

• Weaknesses in management oversight

• Multiple failed barriers

• Increased NRC oversight 31

Questions 32