ML051530478

NRC Slides for Public Meeting with Nuclear Energy Advisory Council (Neac) Ref: Special Inspection Team Results of April 17, 2005 Event

ML051530478
Person / Time
Site:	Millstone
Issue date:	05/18/2005
From:	NRC Region 1
To:
Krohn P, RI/DRP/PB6/610-337-5120
Shared Package
ML051240334	List: ML051240340 ML051530478
References
Download: ML051530478 (15)

Text

NEAC Meeting May 18, 2005 Millstone Unit 3 Special Inspection April 17, 2005, Reactor Trip and Safety Injection Nuclear Regulatory Commission-Region I King of Prussia, PA

NRC Presentation

• NRC Introductions

• Special Inspection Team and Charter

• Event Chronology

• Event Overview and Analysis

• Special Inspection Results

• Discussion 2

NRC Representatives

• Brian E. Holian, Acting Director, Division of Reactor Projects

• Marvin D. Sykes, Chief, Engineering Branch 1, Team Manager

• G. Scott Barber, Senior Project Engineer, Team Leader

• Don Jackson, Senior Project Engineer

• Ronald Nimitz, Senior Health Physicist

• Thomas Sicola, Reactor Inspector

• S. Max Schneider, Senior Resident Inspector

• Nicole Sieller, Reactor Engineer

• Peter Presby, Reactor Inspector 3

Special Inspection Team (SIT)

• Team Staffing 3/4 Four full time members 3/4 Four part time members 3/4 Multidisciplined group with diverse backgrounds 4

Special Inspection Team (SIT)

• Charter / Objectives 3/4 Chronology of event 3/4 Apparent cause(s) 3/4 System response(s) 3/4 Equipment deficiencies including maintenance and surveillance history 3/4 Evaluation of licensee follow-up actions 3/4 Radiological Assessment 5

Event Chronology

• Low steam line pressure signal reactor trip

• Single train safety injection and main steam line isolation

• Main steam safety valve and atmospheric relief valve opening

• Turbine driven auxiliary feedwater pump trip and restart

• Primary power operated relief valve cycling

• Alert declared

• Operator actions to stabilize plant conditions

• Plant shutdown and cooldown 6

Event Overview

• Initial response prompt

• Emergency response organizations activated -

Dominion and NRC

• Some operational / equipment challenges occurred while stabilizing plant conditions

• Licensee successful in achieving cold shutdown

• No consequences to public health and safety 7

Event Analysis

• Dominion Actions 3/4Event Review Team activities initiated 3/4Apparent cause promptly identified by I&C -

Tin Whisker 3/4Timely assessment of radiological conditions 3/4Multiple corrective actions implemented (cause / equipment related) 3/4Additional evaluations initiated 8

9 Millimeters 10

NRC Special Inspection Team Results

• Preliminary Findings 3/4 Turbine Driven Auxiliary Feedwater Pump 3/4 Emergency Operating Procedure Implementation Issues 3/4 Assessment of Plant Conditions 3/4 Simulator Fidelity 3/4 Indicator Design Issues 3/4 Boric Acid Control Program 3/4 Emergency Response Data System Activation 3/4 Thoroughness of Event Review Effort 11

NRC Special Inspection Team Results

• Unresolved items 3/4 Pressurizer snubber - potential inoperability 3/4 Charging system issues 3/4 Simulator issues 3/4 Root Cause Evaluations 12

NRC Special Inspection Team Results

• Observations 3/4 Thoroughness of Event Review Effort 3/4 Emergency Operating Procedure Documentation and Usage 3/4 Extent of Condition Review for Non-Solid State Protection System Cards 13

Radiological Assessment

• Radiological release - well below Regulatory Limits

• No consequence to health or safety of public

• Worker doses were appropriately controlled 14

Conclusions

• Event 3/4 Unit was safely shutdown by operators and placed in a stable condition 3/4 Radiological release well below regulatory limits 3/4 No consequences to public health and safety 15