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{{#Wiki_filter:}} | {{#Wiki_filter:LGS UFSAR CHAPTER 15 - ACCIDENT ANALYSES TABLE OF CONTENTS 15.0 GENERAL 15.0.1 Analytical Objective 15.0.2 Analytical Categories 15.0.3 Transient or Accident Evaluation 15.0.3.1 Identification of Causes and Frequency Classification 15.0.3.1.1 Unacceptable Results for Incidents of Moderate Frequency - Anticipated (Expected) Operational Transients 15.0.3.1.2 Unacceptable Results for Infrequent Incidents - Abnormal (Unexpected) | ||
Operational Transients 15.0.3.1.3 Unacceptable Results for Limiting Faults - Design Basis (Postulated) Accidents 15.0.3.2 Sequence of Events and System Operation 15.0.3.2.1 Single Active Failures or Single Operator Errors 15.0.3.2.2 Analyzed Transients and Nonsafety-Grade Systems or Components 15.0.3.3 Core and System Performance 15.0.3.3.1 Introduction 15.0.3.3.2 Input Parameters and Initial Conditions for Analyzed Events 15.0.3.3.3 Initial Power/Flow Operating Constraints 15.0.3.3.4 Results 15.0.3.4 Barrier Performance 15.0.3.5 Radiological Consequences 15.0.4 Regulatory Guide Conformance 15.0.5 Nuclear Safety Operational Analysis Relationship 15.0.6 Licensing Basis Vs. Emergency Procedure Guidelines 15.0.7 References 15.1 DECREASE IN REACTOR COOLANT TEMPERATURE 15.1.1 Loss of Feedwater Heating 15.1.1.1 Identification of Causes and Frequency Classification 15.1.1.1.1 Identification of Causes 15.1.1.1.2 Frequency Classification 15.1.1.2 Sequence of Events and System Operation 15.1.1.2.1 Sequence of Events 15.1.1.2.2 System Operation 15.1.1.2.3 The Effect of Single Failures and Operator Errors 15.1.1.3 Core and System Performance 15.1.1.3.1 Mathematical Model 15.1.1.3.2 Input Parameters and Initial Conditions 15.1.1.3.3 Results 15.1.1.3.4 Considerations of Uncertainties 15.1.1.4 Barrier Performance 15.1.1.5 Radiological Consequences 15.1.2 Feedwater Controller Failure - Maximum Demand 15.1.2.1 Identification of Causes and Frequency Classification 15.1.2.1.1 Identification of Causes 15.1.2.1.2 Frequency Classification CHAPTER 15 15-i REV. 17, SEPTEMBER 2014 | |||
LGS UFSAR TABLE OF CONTENTS (cont'd) 15.1.2.2 Sequence of Events and System Operation 15.1.2.2.1 Sequence of Events 15.1.2.2.2 System Operation 15.1.2.2.3 The Effect of Single Failures and Operator Errors 15.1.2.3 Core and System Performance 15.1.2.3.1 Mathematical Model 15.1.2.3.2 Input Parameters and Initial Conditions 15.1.2.3.3 Results 15.1.2.3.4 Consideration of Uncertainties 15.1.2.4 Barrier Performance 15.1.2.5 Radiological Consequences 15.1.2.6 Additional Transients Evaluated 15.1.3 Pressure Regulator Failure - Open 15.1.3.1 Identification of Causes and Frequency Classification 15.1.3.1.1 Identification of Causes 15.1.3.1.2 Frequency Classification 15.1.3.2 Sequence of Events and System Operation 15.1.3.2.1 Sequence of Events 15.1.3.2.2 System Operation 15.1.3.2.3 The Effect of Single Failures and Operator Errors 15.1.3.3 Core and System Performance 15.1.3.3.1 Mathematical Model 15.1.3.3.2 Input Parameters and Initial Conditions 15.1.3.3.3 Results 15.1.3.3.4 Consideration of Uncertainties 15.1.3.4 Barrier Performance 15.1.3.5 Radiological Consequences 15.1.4 Inadvertent Main Steam Relief Valve Opening 15.1.4.1 Identification of Causes and Frequency Classification 15.1.4.1.1 Identification of Causes 15.1.4.1.2 Frequency Classification 15.1.4.2 Sequence of Events and System Operation 15.1.4.2.1 Sequence of Events 15.1.4.2.2 System Operation 15.1.4.2.3 The Effect of Single Failures and Operator Errors 15.1.4.3 Core and System Performance 15.1.4.3.1 Mathematical Model 15.1.4.3.2 Input Parameters and Initial Conditions 15.1.4.3.3 Qualitative Results 15.1.4.4 Barrier Performance 15.1.4.5 Radiological Consequences 15.1.5 Spectrum of Steam System Piping Failures Inside and Outside of Containment in a PWR 15.1.6 Inadvertent RHR Shutdown Cooling Operation CHAPTER 15 15-ii REV. 17, SEPTEMBER 2014 | |||
LGS UFSAR TABLE OF CONTENTS (cont'd) 15.1.6.1 Identification of Causes and Frequency Classification 15.1.6.1.1 Identification of Causes 15.1.6.1.2 Frequency Classification 15.1.6.2 Sequence of Events and System Operation 15.1.6.2.1 Sequence of Events 15.1.6.2.2 System Operation 15.1.6.2.3 The Effect of Single Failures and Operator Errors 15.1.6.3 Core and System Performance 15.1.6.4 Barrier Performance 15.1.6.5 Radiological Consequences 15.1.7 References 15.2 INCREASE IN REACTOR PRESSURE 15.2.1 Pressure Regulator Failure - Closed 15.2.1.1 Identification of Causes and Frequency Classification 15.2.1.1.1 Identification of Causes 15.2.1.1.2 Frequency Classification 15.2.1.2 Sequence of Events and System Operation 15.2.1.2.1 Sequence of Events 15.2.1.2.2 Systems Operation 15.2.1.2.3 The Effect of Single Failures and Operator Errors 15.2.1.3 Core and System Performance 15.2.1.3.1 Mathematical Model 15.2.1.3.2 Input Parameters and Initial Conditions 15.2.1.3.3 Results 15.2.1.3.4 Consideration of Uncertainties 15.2.1.4 Barrier Performance 15.2.1.5 Radiological Consequences 15.2.2 Generator Load Rejection 15.2.2.1 Identification of Causes and Frequency Classification 15.2.2.1.1 Identification of Causes 15.2.2.1.2 Frequency Classification 15.2.2.2 Sequence of Events and System Operation 15.2.2.2.1 Sequence of Events 15.2.2.2.2 System Operation 15.2.2.2.3 The Effect of Single Failures and Operator Errors 15.2.2.3 Core and System Performance 15.2.2.3.1 Mathematical Model 15.2.2.3.2 Input Parameters and Initial Conditions 15.2.2.3.3 Results 15.2.2.3.4 Consideration of Uncertainties 15.2.2.4 Barrier Performance 15.2.2.4.1 Generator Load Rejection 15.2.2.4.2 Generator Load Rejection with Failure of Bypass 15.2.2.5 Radiological Consequences CHAPTER 15 15-iii REV. 17, SEPTEMBER 2014 | |||
LGS UFSAR TABLE OF CONTENTS (cont'd) 15.2.3 Turbine Trip 15.2.3.1 Identification of Causes and Frequency Classification 15.2.3.1.1 Identification of Causes 15.2.3.1.2 Frequency Classification 15.2.3.2 Sequence of Events and System Operation 15.2.3.2.1 Sequence of Events 15.2.3.2.2 System Operation 15.2.3.2.3 The Effect of Single Failures and Operator Errors 15.2.3.3 Core and System Performance 15.2.3.3.1 Mathematical Model 15.2.3.3.2 Input Parameters and Initial Conditions 15.2.3.3.3 Results 15.2.3.3.4 Consideration of Uncertainties 15.2.3.4 Barrier Performance 15.2.3.4.1 Turbine Trip 15.2.3.4.2 Turbine Trip with Failure of the Bypass 15.2.3.5 Radiological Consequences 15.2.4 MSIV Closures 15.2.4.1 Identification of Causes and Frequency Classification 15.2.4.1.1 Identification of Causes 15.2.4.1.2 Frequency Classification 15.2.4.2 Sequence of Events and System Operation 15.2.4.2.1 Sequence of Events 15.2.4.2.2 System Operation 15.2.4.2.3 The Effect of Single Failures and Operator Errors 15.2.4.3 Core and System Performance 15.2.4.3.1 Mathematical Model 15.2.4.3.2 Input Parameters and Initial Conditions 15.2.4.3.3 Results 15.2.4.3.4 Consideration of Uncertainties 15.2.4.4 Barrier Performance 15.2.4.4.1 Closure of All Main Steam Isolation Valves 15.2.4.4.2 Closure of One Main Steam Isolation Valve 15.2.4.5 Radiological Consequences 15.2.5 Loss of Condenser Vacuum 15.2.5.1 Identification of Causes and Frequency Classification 15.2.5.1.1 Identification of Causes 15.2.5.1.2 Frequency Classification 15.2.5.2 Sequence of Events and System Operation 15.2.5.2.1 Sequence of Events 15.2.5.2.2 System Operation 15.2.5.2.3 The Effect of Single Failures and Operator Errors 15.2.5.3 Core and System Performance 15.2.5.3.1 Mathematical Model 15.2.5.3.2 Input Parameters and Initial Conditions CHAPTER 15 15-iv REV. 17, SEPTEMBER 2014 | |||
LGS UFSAR TABLE OF CONTENTS (cont'd) 15.2.5.3.3 Results 15.2.5.3.4 Consideration of Uncertainties 15.2.5.4 Barrier Performance 15.2.5.5 Radiological Consequences 15.2.6 Loss of AC Power 15.2.6.1 Identification of Causes and Frequency Classification 15.2.6.1.1 Identification of Causes 15.2.6.1.2 Frequency Classification 15.2.6.2 Sequence of Events and System Operation 15.2.6.2.1 Sequence of Events 15.2.6.2.2 System Operation 15.2.6.2.3 The Effect of Single Failures and Operator Errors 15.2.6.3 Core and System Performance 15.2.6.3.1 Mathematical Model 15.2.6.3.2 Input Parameters and Initial Conditions 15.2.6.3.3 Results 15.2.6.3.4 Consideration of Uncertainties 15.2.6.4 Barrier Performance 15.2.6.4.1 Loss of All Grid Connections 15.2.6.5 Radiological Consequences 15.2.7 Loss of Feedwater Flow 15.2.7.1 Identification of Causes and Frequency Classification 15.2.7.1.1 Identification of Causes 15.2.7.1.2 Frequency Classification 15.2.7.2 Sequence of Events and System Operation 15.2.7.2.1 Sequence of Events 15.2.7.2.2 System Operation 15.2.7.2.3 The Effect of Single Failures and Operator Errors 15.2.7.3 Core and System Performance 15.2.7.3.1 Mathematical Model 15.2.7.3.2 Input Parameters and Initial Conditions 15.2.7.3.3 Results 15.2.7.3.4 Consideration of Uncertainties 15.2.7.4 Barrier Performance 15.2.7.5 Radiological Consequences 15.2.8 Feedwater Line Break 15.2.9 Failure of RHR Shutdown Cooling 15.2.9.1 Identification of Causes and Frequency Classification 15.2.9.1.1 Identification of Causes 15.2.9.1.2 Frequency Classification 15.2.9.2 Sequence of Events and System Operation 15.2.9.2.1 Sequence of Events 15.2.9.2.2 System Operation 15.2.9.2.3 The Effect of Single Failures and Operator Errors CHAPTER 15 15-v REV. 17, SEPTEMBER 2014 | |||
LGS UFSAR TABLE OF CONTENTS (cont'd) 15.2.9.3 Core and System Performance 15.2.9.3.1 Methods, Assumptions, and Conditions 15.2.9.3.2 Mathematical Model 15.2.9.3.3 Input Parameters and Initial Conditions 15.2.9.3.4 Results 15.2.9.4 Barrier Performance 15.2.9.5 Radiological Consequences 15.2.10 Loss of Stator Cooling 15.2.10.1 Identification of Causes and Frequency Classification 15.2.10.1.1 Identification of Causes 15.2.10.1.2 Frequency Classification 15.2.10.2 Sequence of Events and System Operation 15.2.10.2.1 Sequence of Events 15.2.10.2.2 System Operation 15.2.10.2.3 The Effect of Single Failures and Operator Errors 15.2.10.3 Core and System Performance 15.2.10.3.1 Mathematical Model 15.2.10.3.2 Input Parameters and Initial Conditions 15.2.10.3.3 Results 15.2.10.3.4 Consideration of Uncertainties 15.2.10.4 Barrier Performance 15.2.10.5 Radiological Consequences 15.2.11 References 15.3 DECREASE IN REACTOR COOLANT SYSTEM FLOW RATE 15.3.1 Recirculation Pump Trip 15.3.1.1 Identification of Causes and Frequency Classification 15.3.1.1.1 Identification of Causes 15.3.1.1.2 Frequency Classification 15.3.1.2 Sequence of Events and System Operation 15.3.1.2.1 Sequence of Events 15.3.1.2.2 System Operation 15.3.1.2.3 The Effect of Single Failures and Operator Errors 15.3.1.3 Core and System Performance 15.3.1.3.1 Mathematical Model 15.3.1.3.2 Input Parameters and Initial Conditions 15.3.1.3.3 Results 15.3.1.3.4 Consideration of Uncertainties 15.3.1.4 Barrier Performance 15.3.1.4.1 Trip of One Recirculation Pump 15.3.1.4.2 Trip of Two Recirculation Pumps 15.3.1.5 Radiological Consequences 15.3.2 Recirculation Flow Control Failure - Decreasing Flow 15.3.2.1 Identification of Causes and Frequency Classification CHAPTER 15 15-vi REV. 17, SEPTEMBER 2014 | |||
LGS UFSAR TABLE OF CONTENTS (cont'd) 15.3.2.1.1 Identification of Causes 15.3.2.1.2 Frequency Classification 15.3.2.2 Sequence of Events and System Operation 15.3.2.2.1 Sequence of Events 15.3.2.2.2 System Operation 15.3.2.2.3 The Effect of Single Failures and Operator Errors 15.3.2.3 Core and System Performance 15.3.2.3.1 Mathematical Model 15.3.2.3.2 Input Parameters and Initial Conditions 15.3.2.3.3 Results 15.3.2.3.4 Consideration of Uncertainties 15.3.2.4 Barrier Performance 15.3.2.5 Radiological Consequences 15.3.3 Recirculation Pump Seizure 15.3.3.1 Identification of Causes and Frequency Classification 15.3.3.1.1 Identification of Causes 15.3.3.1.2 Frequency Classification 15.3.3.2 Sequence of Events and System Operation 15.3.3.2.1 Sequence of Events 15.3.3.2.2 System Operation 15.3.3.2.3 The Effect of Single Failures and Operator Errors 15.3.3.3 Core and System Performance 15.3.3.3.1 Mathematical Model 15.3.3.3.2 Input Parameters and Initial Conditions 15.3.3.3.3 Results 15.3.3.3.4 Consideration of Uncertainties 15.3.3.4 Barrier Performance 15.3.3.5 Radiological Consequences 15.3.4 Recirculation Pump Shaft Break 15.3.4.1 Identification of Causes and Frequency Classification 15.3.4.1.1 Identification of Causes 15.3.4.1.2 Frequency Classification 15.3.4.2 Sequence of Events and System Operation 15.3.4.2.1 Sequence of Events 15.3.4.2.2 System Operation 15.3.4.2.3 The Effect of Single Failures and Operator Errors 15.3.4.3 Core and System Performance 15.3.4.4 Qualitative Results 15.3.4.5 Barrier Performance 15.3.4.6 Radiological Consequences 15.4 REACTIVITY AND POWER DISTRIBUTION ANOMALIES 15.4.1 Rod Withdrawal Error - Low Power 15.4.1.1 Control Rod Removal Error During Refueling 15.4.1.1.1 Identification of Causes and Frequency Classification CHAPTER 15 15-vii REV. 17, SEPTEMBER 2014 | |||
LGS UFSAR TABLE OF CONTENTS (cont'd) 15.4.1.1.2 Sequence of Events and System Operation 15.4.1.1.3 Core and System Performances 15.4.1.1.4 Barrier Performance 15.4.1.1.5 Radiological Consequences 15.4.1.2 Continuous Rod Withdrawal During Reactor Startup 15.4.1.2.1 Identification of Causes and Frequency Classification 15.4.1.2.2 Sequence of Events and System Operation 15.4.1.2.3 Core and System Performances 15.4.1.2.4 Barrier Performance 15.4.1.2.5 Radiological Consequences 15.4.2 Rod Withdrawal Error - at Power 15.4.2.1 Identification of Causes and Frequency Classification 15.4.2.1.1 Identification of Causes 15.4.2.1.2 Frequency Classification 15.4.2.2 Sequence of Events and System Operation 15.4.2.2.1 Sequence of Events 15.4.2.2.2 System Operation 15.4.2.2.3 The Effect of Single Failures and Operator Errors 15.4.2.3 Core and System Performance 15.4.2.4 Barrier Performance 15.4.2.5 Radiological Consequences 15.4.3 Control Rod Maloperation (System Malfunction or Operator Error) 15.4.4 Startup of Idle Recirculation Pump 15.4.4.1 Identification of Causes and Frequency Classification 15.4.4.1.1 Identification of Causes 15.4.4.2 Sequence of Events and System Operation 15.4.4.2.1 Sequence of Events 15.4.4.2.2 System Operation 15.4.4.2.3 The Effect of Single Failures and Operator Errors 15.4.4.3 Core and System Performance 15.4.4.3.1 Mathematical Model 15.4.4.3.2 Input Parameters and Initial Conditions 15.4.4.3.3 Results 15.4.4.3.4 Consideration of Uncertainties 15.4.4.4 Barrier Performance 15.4.4.5 Radiological Consequences 15.4.5 Recirculation Flow Control Failure with Increasing Flow 15.4.5.1 Identification of Causes and Frequency Classification 15.4.5.1.1 Identification of Causes 15.4.5.1.2 Frequency Classification 15.4.5.2 Sequence of Events and System Operation 15.4.5.2.1 Sequence of Events 15.4.5.2.2 System Operation 15.4.5.2.3 The Effect of Single Failures and Operator Errors CHAPTER 15 15-viii REV. 17, SEPTEMBER 2014 | |||
LGS UFSAR TABLE OF CONTENTS (cont'd) 15.4.5.3 Core and System Performance 15.4.5.3.1 Mathematical Model 15.4.5.3.2 Input Parameters and Initial Conditions 15.4.5.3.3 Results 15.4.5.3.4 Consideration of Uncertainties 15.4.5.4 Barrier Performance 15.4.5.5 Radiological Consequences 15.4.6 Chemical and Volume Control System Malfunctions 15.4.7 Misplaced Bundle Accident 15.4.7.1 Identification of Causes and Frequency Classification 15.4.7.1.1 Identification of Causes 15.4.7.1.2 Frequency Classification 15.4.7.2 Sequence of Events and System Operation 15.4.7.2.1 The Effect of Single Failures and Operator Errors 15.4.7.3 Core and System Performance 15.4.7.4 Barrier Performance 15.4.7.5 Radiological Consequences 15.4.8 Spectrum of Rod Ejection Accidents 15.4.9 Control Rod-Drop Accident 15.4.9.1 Identification of Causes and Frequency Classification 15.4.9.2 Sequence of Events and System Operation 15.4.9.3 Core and System Performance 15.4.9.3.1 Mathematical Model 15.4.9.3.2 Input Parameters and Initial Conditions 15.4.9.3.3 Results 15.4.9.4 Barrier Performance 15.4.9.5 Radiological Consequences for the CRDA 15.4.9.5.1 Regulatory Approach 15.4.9.5.2 Dose Acceptance Criteria 15.4.9.5.3 Computer Codes 15.4.9.5.4 Source Terms 15.4.9.5.5 Methodology 15.4.9.5.6 Atmospheric Dispersion Factors (X/Qs) 15.4.9.5.7 Summary and Conclusions 15.4.10 References 15.5 INCREASE IN REACTOR COOLANT INVENTORY 15.5.1 Inadvertent HPCI Startup 15.5.1.1 Identification of Causes and Frequency Classification 15.5.1.1.1 Identification of Causes 15.5.1.1.2 Frequency Classification 15.5.1.2 Sequence of Events and System Operation CHAPTER 15 15-ix REV. 17, SEPTEMBER 2014 | |||
LGS UFSAR TABLE OF CONTENTS (cont'd) 15.5.1.2.1 Sequence of Events 15.5.1.2.2 System Operation 15.5.1.2.3 The Effect of Single Failures and Operator Errors 15.5.1.3 Core and System Performance 15.5.1.3.1 Mathematical Model 15.5.1.3.2 Input Parameter and Initial Conditions 15.5.1.3.3 Results 15.5.1.3.4 Consideration of Uncertainties 15.5.1.4 Barrier Performance 15.5.1.5 Radiological Consequences 15.5.2 Chemical Volume Control System Malfunction (or Operator Error) 15.5.3 Other BWR Transients Which Increase Reactor Coolant Inventory 15.6 DECREASE IN REACTOR COOLANT INVENTORY 15.6.1 Inadvertent Main Steam Relief Valve Opening 15.6.2 Instrument Line Pipe Break 15.6.2.1 Identification of Causes and Frequency Classification 15.6.2.1.1 Identification of Causes and Event Description 15.6.2.1.2 Frequency Classification 15.6.2.2 Sequence of Events and System Operation 15.6.2.2.1 Sequence of Events 15.6.2.2.2 System Operation 15.6.2.2.3 The Effect of Single Failures and Operator Errors 15.6.2.3 Core and System Performance 15.6.2.3.1 Qualitative Summary 15.6.2.3.2 Quantitative Results 15.6.2.3.3 Consideration of Uncertainties 15.6.2.4 Barrier Performance 15.6.2.4.1 General 15.6.2.5 Radiological Consequences 15.6.2.5.1 Design Basis Analysis 15.6.2.5.2 Realistic Analysis 15.6.3 Steam Generator Tube Failure 15.6.4 Steam System Piping Break Outside Primary Containment 15.6.4.1 Identification of Causes and Frequency Classification 15.6.4.1.1 Identification of Causes 15.6.4.1.2 Frequency Classification 15.6.4.2 Sequence of Events and System Operation 15.6.4.2.1 Sequence of Events 15.6.4.2.2 System Operation 15.6.4.2.3 The Effect of Single Failures and Operator Errors 15.6.4.3 Core and System Performance CHAPTER 15 15-x REV. 17, SEPTEMBER 2014 | |||
LGS UFSAR TABLE OF CONTENTS (cont'd) 15.6.4.3.1 Input Parameters and Initial Conditions 15.6.4.3.2 Results 15.6.4.3.3 Consideration of Uncertainties 15.6.4.4 Barrier Performance 15.6.4.5 Radiological Consequences for the MSLB 15.6.4.5.1 Regulatory Approach 15.6.4.5.2 Dose Acceptance Criteria 15.6.4.5.3 Computer Codes 15.6.4.5.4 Source Terms 15.6.4.5.5 Methodology 15.6.4.5.6 Atmospheric Dispersion Factors (X/Qs) 15.6.4.5.7 Summary and Conclusions 15.6.5 Loss-of-Coolant Accidents (Resulting from Spectrum of Postulated Piping Breaks Within the Reactor Coolant Pressure Boundary) Inside Primary Containment 15.6.5.1 Identification of Causes and Frequency Classification 15.6.5.1.1 Identification of Causes 15.6.5.1.2 Frequency Classification 15.6.5.2 Sequence of Events and System Operation 15.6.5.2.1 Sequence of Events 15.6.5.2.2 System Operation 15.6.5.2.3 The Effect of Single Failures and Operator Errors 15.6.5.3 Core and System Performance 15.6.5.3.1 Mathematical Model 15.6.5.3.2 Input Parameters and Initial Conditions 15.6.5.3.3 Results 15.6.5.3.4 Consideration of Uncertainties 15.6.5.4 Barrier Performance 15.6.5.5 Radiological Consequences for the LOCA 15.6.5.5.1 Regulatory Approach 15.6.5.5.2 Dose Acceptance Criteria 15.6.5.5.3 Computer Codes 15.6.5.5.4 Source Terms 15.6.5.5.5 Methodology 15.6.5.5.6 Atmospheric Dispersion Factors (X/Qs) 15.6.5.5.7 Summary and Conclusions 15.6.6 Feedwater Line Break Outside Primary Containment 15.6.6.1 Identification of Causes and Frequency Classification 15.6.6.1.1 Identification of Causes 15.6.6.1.2 Frequency Classification 15.6.6.2 Sequence of Events and System Operation 15.6.6.2.1 Sequence of Events 15.6.6.2.2 System Operation 15.6.6.2.3 The Effect of Single Failures and Operator Errors 15.6.6.3 Core and System Performance 15.6.6.3.1 Qualitative Summary CHAPTER 15 15-xi REV. 17, SEPTEMBER 2014 | |||
LGS UFSAR TABLE OF CONTENTS (cont'd) 15.6.6.3.2 Qualitative Results 15.6.6.3.3 Consideration of Uncertainties 15.6.6.4 Barrier Performance 15.6.6.5 Radiological Consequences 15.6.6.5.1 Design Basis Analysis 15.6.6.5.2 Realistic Analysis 15.6.7 Loss of Feedwater Flow 15.6.8 References 15.7 RADIOACTIVE RELEASES FROM SUBSYSTEMS AND COMPONENTS 15.7.1 Radioactive Gas Waste System Leak or Failure 15.7.1.1 Main Condenser Offgas Treatment System Failure 15.7.1.1.1 Identification of Causes and Frequency Classification 15.7.1.1.2 Sequence of Events and System Operation 15.7.1.1.3 Core and System Performance 15.7.1.1.4 Barrier Performance 15.7.1.1.5 Radiological Consequences 15.7.1.2 Malfunction of Main Turbine Gland Sealing System 15.7.1.2.1 Identification of Causes and Frequency Classification 15.7.1.2.2 Sequence of Events and System Operation 15.7.1.2.3 Core and System Performance 15.7.1.2.4 Barrier Analysis 15.7.1.2.5 Radiological Consequences 15.7.1.3 Failure of Steam Jet Air Ejector Lines 15.7.1.3.1 Identification of Causes and Frequency Classification 15.7.1.3.2 Sequence of Events and System Operation 15.7.1.3.3 Core and System Performance 15.7.1.3.4 Barrier Analysis 15.7.1.3.5 Radiological Consequences 15.7.2 Liquid Radioactive Waste System Failure 15.7.2.1 Identification of Causes and Frequency Classification 15.7.2.1.1 Identification of Causes 15.7.2.1.2 Frequency Classification 15.7.2.2 Sequence of Events and System Operation 15.7.2.3 Core and System Performance 15.7.2.4 Barrier Performance 15.7.2.5 Radiological Consequences 15.7.2.5.1 Design Basis Analysis 15.7.2.5.2 Realistic Analysis 15.7.3 Postulated Radioactive Releases Due to Liquid Radwaste Tank Failure 15.7.4 Fuel Handling Accident 15.7.4.1 Identification of Causes and Frequency Classification CHAPTER 15 15-xii REV. 17, SEPTEMBER 2014 | |||
LGS UFSAR TABLE OF CONTENTS (cont'd) 15.7.4.1.1 Identification of Causes 15.7.4.1.2 Frequency Classification 15.7.4.2 Sequence of Events and System Operation 15.7.4.2.1 Sequence of Events 15.7.4.2.2 Identification of Operator Actions 15.7.4.2.3 System Operation 15.7.4.2.4 The Effect of Single Failures and Operator Errors 15.7.4.3 Core and System Performance 15.7.4.3.1 Mathematical Model 15.7.4.3.2 Input Parameters and Initial Conditions 15.7.4.3.3 Results 15.7.4.4 Barrier Performance 15.7.4.5 Radiological Consequences for the FHA 15.7.4.5.1 Regulatory Approach 15.7.4.5.2 Dose Acceptance Criteria 15.7.4.5.3 Computer Codes 15.7.4.5.4 Source Terms 15.7.4.5.5 Methodology 15.7.4.5.6 Atmospheric Dispersion Factors (X/Qs) 15.7.4.5.7 Summary and Conclusions 15.7.5 Spent Fuel Cask-Drop Accident 15.7.6 Movement of Loads Without Secondary Containment 15.7.7 References 15.8 ANTICIPATED TRANSIENTS WITHOUT SCRAM 15.8.1 Requirements 15.8.2 Plant Capabilities 15.8.3 Equipment Description 15.8.3.1 Redundant Reactivity Control System 15.8.3.2 Alternate Rod Insertion 15.8.3.3 Recirculation Pump Trip 15.8.3.4 Feedwater Runback 15.8.3.5 Standby Liquid Control System 15.8.3.6 Scram Discharge Volume 15.8.3.7 HPCI Flow Split Modification 15.8.4 References 15.9 PLANT NUCLEAR SAFETY OPERATIONAL ANALYSIS (A SYSTEM LEVEL/ | |||
QUALITATIVE-TYPE PLANT FMEA) 15.9.1 Objectives CHAPTER 15 15-xiii REV. 17, SEPTEMBER 2014 | |||
LGS UFSAR TABLE OF CONTENTS (cont'd) 15.9.2 Approach to Operational Nuclear Safety 15.9.2.1 Classification of Plant Events 15.9.2.2 NSOA Development 15.9.2.2.1 Scope and Classification of Plant Events 15.9.2.2.2 Safety and Power Generation 15.9.2.2.3 Frequency of Events 15.9.2.2.4 Conservative Analysis Margins 15.9.2.2.5 Safety Function Definition 15.9.2.2.6 Envelope and Actual Event Analyses 15.9.2.2.7 Analysis Consistency 15.9.2.3 Comprehensiveness of the Analysis 15.9.2.4 Systematic Approach of the Analysis 15.9.2.5 Relationship of Nuclear Safety Operational Analysis to Safety Analyses of Chapter 15 15.9.2.6 Relationship Between NSOA and Operational Requirements, Technical Specifications, Design Bases, and Single Active Component Failure Aspects 15.9.2.7 Unacceptable Consequences Criteria 15.9.2.8 General Nuclear Safety Operational Criteria 15.9.3 Method of Analysis 15.9.3.1 General Approach 15.9.3.2 BWR Operating States 15.9.3.3 Selection of Events for Analysis 15.9.3.3.1 Normal Operations 15.9.3.3.2 Anticipated Operational Transients 15.9.3.3.3 Abnormal Operational Transients 15.9.3.3.4 Design Basis Accidents 15.9.3.3.5 Special Events 15.9.3.4 Applicability of Events to Operating States 15.9.3.5 Guidelines for Event Analysis 15.9.3.6 Steps in an Operational Analysis 15.9.4 Display of Operational Analysis Results 15.9.4.1 General 15.9.4.2 Protection Sequence and Safety System Auxiliary Diagrams 15.9.5 Bases for Technical Specifications 15.9.5.1 Surveillance Test Requirements 15.9.5.2 Limiting Condition for Operation 15.9.5.3 Maximum Allowable Out-of-Service Time 15.9.6 Operational Analyses 15.9.6.1 Safety System Auxiliaries 15.9.6.2 Normal Operations 15.9.6.2.1 General 15.9.6.2.2 Event Definitions 15.9.6.2.3 Required Safety Actions/Related Unacceptable Consequences CHAPTER 15 15-xiv REV. 17, SEPTEMBER 2014 | |||
LGS UFSAR TABLE OF CONTENTS (cont'd) 15.9.6.2.4 Operational Safety Evaluations 15.9.6.3 Anticipated Operational Transients 15.9.6.3.1 General 15.9.6.3.2 Required Safety Actions/Related Unacceptable Consequences 15.9.6.3.3 Event Definitions and Operational Safety Evaluations 15.9.6.4 Abnormal Operational Transients 15.9.6.4.1 General 15.9.6.4.2 Required Safety Actions/Related Unacceptable Consequences 15.9.6.4.3 Event Definition and Operational Safety Evaluation 15.9.6.5 Design Basis Accidents 15.9.6.5.1 General 15.9.6.5.2 Required Safety Actions/Unacceptable Consequences 15.9.6.5.3 Event Definition and Operational Safety Evaluations 15.9.6.6 Special Events 15.9.6.6.1 General 15.9.6.6.2 Required Safety Action/Unacceptable Consequences 15.9.6.6.3 Event Definitions and Operational Safety Evaluation 15.9.7 Summary and Conclusions 15.10 ACCIDENT DOSE MODEL DESCRIPTIONS 15.10.1 Offsite Dose Model 15.10.1.1 Total Body Gamma Dose 15.10.1.2 Thyroid Inhalation Dose 15.10.1.3 Beta Skin Dose 15.10.2 Control Room Doses 15.10.2.1 Control Room X/Q Model 15.10.2.2 Control Room Dose Model 15.10.3 References 15.11 PROBABILISTIC RISK ASSESSMENT 15.12 STATION BLACKOUT 15.12.1 Requirements and Limerick Response 15.12.2 Determination of Required Coping Duration 15.12.3 Use of Alternate Ac Source 15.12.4 Assessment of Ability to Cope with a Station Blackout 15.12.4.1 Condensate Inventory for Decay Heat Removal 15.12.4.2 Class 1E Battery Capacity 15.12.4.3 Compressed Gas 15.12.4.4 Effects of Loss of Ventilation CHAPTER 15 15-xv REV. 17, SEPTEMBER 2014 | |||
LGS UFSAR TABLE OF CONTENTS (cont'd) 15.12.4.5 Containment Isolation 15.12.4.6 Reactor Coolant Inventory 15.12.5 Procedures for SBO 15.12.6 References Appendix 15A Continuous Control Rod Withdrawal Transient Analysis Appendix 15B Reload Evaluation CHAPTER 15 15-xvi REV. 17, SEPTEMBER 2014 | |||
LGS UFSAR CHAPTER 15 - ACCIDENT ANALYSES LIST OF TABLES TABLE TITLE 15.0-1 Summary of Initial Core Transients 15.0-1A Transient Analysis Results at Rerate Power 15.0-2 Input Parameters and Initial Conditions for Initial Core Transients 15.0-2A Input Parameters and Initial Conditions For Rerate Power Transient Analysis 15.0-3 Summary of Accidents 15.0-4 Atmospheric Dispersion Parameters 15.0-5 Required Operating Limit CPR Values for Initial Core Transients 15.0-6 Transients Where Nonsafety-Grade Systems/Components are Actuated During the Course of the Event 15.1-1 Sequence of Events for Inadvertent RHR Shutdown Cooling Operation 15.1-2 Sequence of Events for Loss of Feedwater Heating 15.1-3 Sequence of Events for Feedwater Controller Failure 15.1-4 Sequence of Events for Pressure Regulator Failure 15.1-5 Sequence of Events for Inadvertent Main Steam Relief Valve Opening 15.2-1 Sequence of Events for Turbine-Generator Load Rejection With Bypass 15.2-2 Sequence of Events for Turbine-Generator Load Rejection Without Bypass 15.2-3 Sequence of Events for Turbine Trip with Bypass 15.2-4 Sequence of Events for Turbine Trip Without Bypass 15.2-5 Sequence of Events for MSIV Closure 15.2-6 Typical Rates of Decay for Condenser Vacuum 15.2-7 Sequence of Events for Loss of Condenser Vacuum 15.2-8 Trip Signals Associated with Loss of Condenser Vacuum 15.2-9 Sequence of Events for Loss of Auxiliary Power Transformer 15.2-10 Sequence of Events for Loss of all Grid Connections CHAPTER 15 15-xvii REV. 17, SEPTEMBER 2014 | |||
LGS UFSAR LIST OF TABLES (cont'd) 15.2-11 Sequence of Events for Loss of Feedwater Flow 15.2-12 Sequence of Events for Failure of RHR Shutdown Cooling 15.2-13 Input Parameters for Evaluation of Failure of RHR Shutdown Cooling 15.2-14 Significant Initial Conditions and Results for the Generator Load Rejection Without Bypass and EOC-RPT 15.2-15 Sequence of Events for Loss of Stator Cooling 15.3-1 Sequence of Events for Trip of One Recirculation Pump 15.3-2 Sequence of Events for Trip of Both Recirculation Pumps 15.3-3 Sequence of Events for Recirculation Pump Seizure 15.4-1 Sequence of Events for Control Rod Withdrawal Error in Power Range 15.4-2 Intentionally Left Blank 15.4-3 Deleted. | |||
15.4-4 Sequence of Events for Recirculation Flow Control Failure With Increasing Flow 15.4-5 Sequence of Events for Misplaced Bundle Accident 15.4-6 Initial Conditions and Results of Fuel Bundle Loading Error 15.4-7 This was left blank intentionally. | |||
15.4-8 This was left blank intentionally. | |||
15.4-9 This was left blank intentionally. | |||
15.4-10 This was left blank intentionally. | |||
15.4-11 CRDA - Radiological Consequences Key Inputs and Assumptions 15.4-12 X/Q Values for CRDA 15.4-13 CRDA Radiological Consequences Analysis Results 15.5-1 Sequence of Events: Inadvertent HPCI Startup 15.6-1 Sequence of Events for Instrument Line Break 15.6-2 Instrument Line Break Accident: Parameters Tabulated for Postulated Accident Analyses CHAPTER 15 15-xviii REV. 17, SEPTEMBER 2014 | |||
LGS UFSAR LIST OF TABLES (cont'd) 15.6-3 Instrument Line Failure: Activity Airborne in Reactor Enclosure 15.6-4 Instrument Line Failure: Activity Released to the Environment 15.6-5 Instrument Line Failure: Activity Airborne in Reactor Enclosure 15.6-6 Instrument Line Break: Activity Released to the Environment 15.6-7 Instrument Line Failure: Radiological Effects 15.6-8 Sequence of Events for Steam Line Break Outside Primary Containment 15.6-9 MSLB - Radiological Consequences Key Inputs and Assumptions 15.6-10 MSLB X/Q Values 15.6-11 MSLB Radiological Consequences Analysis Results 15.6-12 Not Used 15.6-13 Loss-of-Coolant Accident: Personnel Dose Inputs 15.6-14 Loss-of-Coolant Accident: Source Term 15.6-15 Loss-of-Coolant Accident: Containment Parameters 15.6-16 Loss-of-Coolant Accident: Control Room Parameters 15.6-17 Loss-of-Coolant Accident: Removal Inputs 15.6-18 Loss-of-Coolant Accident: Radiological Dose Summary 15.6-19 Loss-of-Coolant Accident: Control Room Dispersion Factors 15.6-20 Loss-of-Coolant Accident: Offsite Dispersion Factors 15.6-21 Deleted 15.6-22 Deleted 15.6-23 Sequence of Events for Feedwater Line Break Outside Primary Containment 15.6-24 Feedwater Line Break Accident: Parameters Tabulated for Postulated Accident Analyses 15.6-25 Feedwater Line Break: Activity Released to the Environment 15.6-26 Feedwater Line Break: Radiological Effects CHAPTER 15 15-xix REV. 17, SEPTEMBER 2014 | |||
LGS UFSAR LIST OF TABLES (cont'd) 15.6-27 Loss-of-Coolant Accident: Sequence of Events for Radiological Consequence Analysis 15.7-1 Sequence of Events for Main Condenser Offgas Treatment System Failure 15.7-2 Radioactive Gas Waste System Failure: Parameters Tabulated for Postulated Accident Analyses 15.7-3 Offgas Equipment Failure Release Assumptions: Release Fractions Assumed for Design Basis and Realistic Analysis 15.7-4 Main Condenser Offgas Treatment System Failure (Charcoal Adsorber Vessels): Activity Released to the Environment 15.7-5 Main Condenser Offgas Treatment System Failure (Charcoal Adsorber Vessels): Activity Released to the Environment 15.7-6 Main Condenser Offgas Treatment System Failure (Charcoal Adsorber Vessels): Radiological Effects 15.7-7 Failure of Steam Jet Air Ejector Lines: Parameters Tabulated for Postulated Accident Analyses 15.7-8 Failure of Steam Jet Air Ejector Lines: Activity Released to the Environment 15.7-9(a) Failure of Steam Jet Air Ejector Lines: Radiological Effects 15.7-9(b) Main Condenser Offgas Treatment System Failure: Radiological Effects 15.7-10 Sequence of Events: Liquid Radwaste Tank Failure 15.7-11 Liquid Radwaste Tank Failure: Parameters Tabulated for Postulated Accident Analyses 15.7-12 Liquid Radwaste Tank Failure (RWCU Phase Separator): Activity Released to the Environment 15.7-13 Liquid Radwaste Tank Failure (RWCU Phase Separator): Activity Released to the Environment 15.7-14 Liquid Radwaste Tank Failure (RWCU Phase Separator): Radiological Effects 15.7-15 Sequence of Events for Fuel Handling Accident 15.7-16 FHA - Radiological Consequences Key Inputs and Parameters 15.7-17 FHA X/Q Values CHAPTER 15 15-xx REV. 17, SEPTEMBER 2014 | |||
LGS UFSAR LIST OF TABLES (cont'd) 15.7-18 FHA Radiological Consequences Analysis Results 15.7-19 Not Used 15.7-20 Not Used 15.7-21 Not Used 15.7-22 Potential Energy of Light Loads to be Handled Over Spent Fuel 15.9-1 Normal Operation 15.9-2 Anticipated Operational Transients 15.9-3 Abnormal Operational Transients 15.9-4 Design Basis Accidents 15.9-5 Special Events 15.9-6 Unacceptable Consequences Criteria - Plant Event Category - Normal Operation 15.9-7 Unacceptable Consequences Criteria - Plant Event Category - Anticipated Operational Transients 15.9-8 Unacceptable Consequences Criteria - Plant Event Category - Abnormal Operational Transients 15.9-9 Unacceptable Consequences Criteria - Plant Event Category - Design Basis Accidents 15.9-10 Unacceptable Consequences Considerations - Plant Event Category - | |||
Special Events 15.9-11 BWR Operating States 15.10-1 Physical Data for Isotopes 15.10-2 Accident Atmospheric Dilution Factors - X/Q 15.10.3 Breathing Rates for Offsite Dose Calculations CHAPTER 15 15-xxi REV. 17, SEPTEMBER 2014 | |||
LGS UFSAR CHAPTER 15 - ACCIDENT ANALYSES LIST OF FIGURES FIGURE TITLE 15.0-1 Typical Power/Flow Map 15.0-2 Scram Position and Reactivity Characteristics 15.0-3 Minimum Operating CPR Limits versus Scram Speed 15.1-1 Feedwater Controller Failure Without Turbine Bypass 15.1-2 Intentionally Left Blank 15.1-3 Feedwater Controller Failure, Maximum Demand, with High Level Turbine Trip 15.1-4 Pressure Regulator Failure Open 15.2-1 Generator Load Rejection, Trip Scram, Bypass - On, RPT - On 15.2-2 Generator Load Rejection without Bypass 15.2-3 Turbine Trip, Trip Scram, Bypass - On, RPT - On 15.2-4 Turbine Trip without Bypass, Trip Scram 15.2-5 Three Second Closure of all Main Steam Line Isolation Valves 15.2-6 Loss of Condenser Vacuum 15.2-7 Loss of Auxiliary Power Transformer 15.2-8 Loss of All Grid Connections 15.2-9 Loss of All Feedwater Flow 15.2-10 Summary of Paths Available to Achieve Cold Shutdown 15.2-11 Use of ADS and RHR Suppression Pool Cooling to Achieve Cold Shutdown 15.2-12 Vessel Temperature and Pressure versus Time to Achieve Cold Shutdown with ADS and RHR Suppression Pool Cooling 15.2-13 Suppression Pool Temperature versus Time to Achieve Cold Shutdown with ADS and RHR Suppression Pool Cooling CHAPTER 15 15-xxii REV. 17, SEPTEMBER 2014 | |||
LGS UFSAR LIST OF FIGURES (cont'd) 15.2-14 Generator Load Rejection, No Bypass, No EOC-RPT 15.3-1 Trip of One Recirculation Pump Motor 15.3-2 Trip of Both Recirculation Pump Motors 15.3-3 Seizure of One Recirculation Pump 15.4-1 This figure has been deleted. | |||
15.4-2 Deleted 15.4-3 Recirculation Failure - Increasing Flow 15.4-4 Deleted 15.5-1 Inadvertent Startup of HPCI Pump 15.6-1 Leakage Path for Instrument Line Break 15.6-2 Steam Flow Schematic for Steam Break Outside Primary Containment 15.6-3 Leakage Flow for LOCA 15.6-4 Leakage Path for Feedwater Line Break Outside Primary Containment 15.7-1 Leakage Path for Fuel Handling Accident 15.9-1 Block Diagram of Method Used to Derive Nuclear Safety Operational Requirements System, Level Qualitative FMEA, Design Basis Confirmation Audits, and Technical Specifications 15.9-2 Possible Inconsistencies in the Selection of Nuclear Safety Operational Requirements 15.9-3 INTENTIONALLY LEFT BLANK 15.9-4 Format for Protection Sequence Diagrams 15.9-5 Format for Safety System Auxiliary Diagrams 15.9-6 INTENTIONALLY LEFT BLANK 15.9-7 Safety System Auxiliaries 15.9-8 Safety System Auxiliaries 15.9-9 Safety Action Sequences for Normal Operation in State A 15.9-10 Safety Action Sequences for Normal Operation in State B 15.9-11 Safety Action Sequences for Normal Operation in State C CHAPTER 15 15-xxiii REV. 17, SEPTEMBER 2014 | |||
LGS UFSAR LIST OF FIGURES (cont'd) 15.9-12 Safety Action Sequences for Normal Operation in State D 15.9-13 Protection Sequence for Manual or Inadvertent Scram 15.9-14 Protection Sequences for Loss of Plant Instrument and Service Air System 15.9-15 Protection Sequences for Inadvertent Startup of NSSS Pump 15.9-16 Protection Sequences for Inadvertent Startup of Idle Recirculation Loop Pump 15.9-17 Protection Sequence for Recirculation Loop Flow Control Failure (Increasing Flow) 15.9-18 Protection Sequence for Recirculation Loop Flow Control Failure (Decreasing Flow) 15.9-19 Protection Sequences for Recirculation Loop Pump Trip (One or Both) 15.9-20 Protection Sequences for Isolation of All Main Steam Lines 15.9-21 Protection Sequences for Isolation of One Main Steam Line 15.9-22 Protection Sequences for Inadvertent Opening of an MSRV 15.9-23 Protection Sequence for Control Rod Withdrawal Error for Startup and Refueling Operations 15.9-24 Protection Sequence for Control Rod Withdrawal Error - Power Operation 15.9-25 Protection Sequences for RHR - Loss of Shutdown Cooling 15.9-26 Protection Sequences for RHR (Shutdown Cooling) Increased Cooling 15.9-27 Protection Sequences for Loss of Feedwater Flow 15.9-28 Protection Sequence for Loss of a Feedwater Heater 15.9-29 Protection Sequences for Feedwater Controller Failure (Maximum Demand) 15.9-30 Protection Sequences for Pressure Regulator Failure (Open) 15.9-31 Protection Sequences for Pressure Regulator Failure (Closed) 15.9-32 Protection Sequences for Main Turbine Trip with Bypass System Operation 15.9-33 Protection Sequences for Loss of Main Condenser Vacuum CHAPTER 15 15-xxiv REV. 17, SEPTEMBER 2014 | |||
LGS UFSAR LIST OF FIGURES (cont'd) 15.9-34 Protection Sequences for Main Generator Trip with Bypass System Operation 15.9-35 Protection Sequences for Achieving Shutdown Cooling with Reactor Vessel Isolated 15.9-36 Protection Sequences for Loss of Normal Ac Power (Grid Connection Loss) 15.9-37 Protection Sequences for Main Generator Trip With Bypass System Failure 15.9-38 Protection Sequences for Main Turbine Trip With Bypass System Failure 15.9-39 Protection Sequence for Inadvertent Loading and Operation of Fuel Assembly in Improper Position 15.9-40 Protection Sequences for Recirculation Loop Pump Seizure 15.9-41 Protection Sequences for Recirculation Pump Shaft Break 15.9-42 Protection Sequences for Control Rod-Drop Accident 15.9-43 Protection Sequences for Fuel Handling Accident 15.9-44 Protection Sequences for Loss of Coolant Piping Breaks in RCPB Inside Containment 15.9-45 Protection Sequences for Piping Breaks Outside Containment 15.9-46 Protection Sequences for Gaseous Radwaste System Leak or Failure 15.9-47 Protection Sequences for Augmented Offgas Treatment System Failure 15.9-48 Protection Sequences for Liquid Radwaste System Leak or Failure 15.9-49 Protection Sequences for Liquid Radwaste System - Storage Tank Failure 15.9-50 Protection Sequences for Shipping Cask Drop 15.9-51 Protection Sequences for Reactor Shutdown/ATWS 15.9-52 Protection Sequences for Reactor Shutdown From Outside Control Room 15.9-53 Protection Sequences for Reactor Shutdown Without Control Rods CHAPTER 15 15-xxv REV. 17, SEPTEMBER 2014}} | |||
Latest revision as of 13:00, 19 January 2022
Text
LGS UFSAR CHAPTER 15 - ACCIDENT ANALYSES TABLE OF CONTENTS 15.0 GENERAL 15.0.1 Analytical Objective 15.0.2 Analytical Categories 15.0.3 Transient or Accident Evaluation 15.0.3.1 Identification of Causes and Frequency Classification 15.0.3.1.1 Unacceptable Results for Incidents of Moderate Frequency - Anticipated (Expected) Operational Transients 15.0.3.1.2 Unacceptable Results for Infrequent Incidents - Abnormal (Unexpected)
Operational Transients 15.0.3.1.3 Unacceptable Results for Limiting Faults - Design Basis (Postulated) Accidents 15.0.3.2 Sequence of Events and System Operation 15.0.3.2.1 Single Active Failures or Single Operator Errors 15.0.3.2.2 Analyzed Transients and Nonsafety-Grade Systems or Components 15.0.3.3 Core and System Performance 15.0.3.3.1 Introduction 15.0.3.3.2 Input Parameters and Initial Conditions for Analyzed Events 15.0.3.3.3 Initial Power/Flow Operating Constraints 15.0.3.3.4 Results 15.0.3.4 Barrier Performance 15.0.3.5 Radiological Consequences 15.0.4 Regulatory Guide Conformance 15.0.5 Nuclear Safety Operational Analysis Relationship 15.0.6 Licensing Basis Vs. Emergency Procedure Guidelines 15.0.7 References 15.1 DECREASE IN REACTOR COOLANT TEMPERATURE 15.1.1 Loss of Feedwater Heating 15.1.1.1 Identification of Causes and Frequency Classification 15.1.1.1.1 Identification of Causes 15.1.1.1.2 Frequency Classification 15.1.1.2 Sequence of Events and System Operation 15.1.1.2.1 Sequence of Events 15.1.1.2.2 System Operation 15.1.1.2.3 The Effect of Single Failures and Operator Errors 15.1.1.3 Core and System Performance 15.1.1.3.1 Mathematical Model 15.1.1.3.2 Input Parameters and Initial Conditions 15.1.1.3.3 Results 15.1.1.3.4 Considerations of Uncertainties 15.1.1.4 Barrier Performance 15.1.1.5 Radiological Consequences 15.1.2 Feedwater Controller Failure - Maximum Demand 15.1.2.1 Identification of Causes and Frequency Classification 15.1.2.1.1 Identification of Causes 15.1.2.1.2 Frequency Classification CHAPTER 15 15-i REV. 17, SEPTEMBER 2014
LGS UFSAR TABLE OF CONTENTS (cont'd) 15.1.2.2 Sequence of Events and System Operation 15.1.2.2.1 Sequence of Events 15.1.2.2.2 System Operation 15.1.2.2.3 The Effect of Single Failures and Operator Errors 15.1.2.3 Core and System Performance 15.1.2.3.1 Mathematical Model 15.1.2.3.2 Input Parameters and Initial Conditions 15.1.2.3.3 Results 15.1.2.3.4 Consideration of Uncertainties 15.1.2.4 Barrier Performance 15.1.2.5 Radiological Consequences 15.1.2.6 Additional Transients Evaluated 15.1.3 Pressure Regulator Failure - Open 15.1.3.1 Identification of Causes and Frequency Classification 15.1.3.1.1 Identification of Causes 15.1.3.1.2 Frequency Classification 15.1.3.2 Sequence of Events and System Operation 15.1.3.2.1 Sequence of Events 15.1.3.2.2 System Operation 15.1.3.2.3 The Effect of Single Failures and Operator Errors 15.1.3.3 Core and System Performance 15.1.3.3.1 Mathematical Model 15.1.3.3.2 Input Parameters and Initial Conditions 15.1.3.3.3 Results 15.1.3.3.4 Consideration of Uncertainties 15.1.3.4 Barrier Performance 15.1.3.5 Radiological Consequences 15.1.4 Inadvertent Main Steam Relief Valve Opening 15.1.4.1 Identification of Causes and Frequency Classification 15.1.4.1.1 Identification of Causes 15.1.4.1.2 Frequency Classification 15.1.4.2 Sequence of Events and System Operation 15.1.4.2.1 Sequence of Events 15.1.4.2.2 System Operation 15.1.4.2.3 The Effect of Single Failures and Operator Errors 15.1.4.3 Core and System Performance 15.1.4.3.1 Mathematical Model 15.1.4.3.2 Input Parameters and Initial Conditions 15.1.4.3.3 Qualitative Results 15.1.4.4 Barrier Performance 15.1.4.5 Radiological Consequences 15.1.5 Spectrum of Steam System Piping Failures Inside and Outside of Containment in a PWR 15.1.6 Inadvertent RHR Shutdown Cooling Operation CHAPTER 15 15-ii REV. 17, SEPTEMBER 2014
LGS UFSAR TABLE OF CONTENTS (cont'd) 15.1.6.1 Identification of Causes and Frequency Classification 15.1.6.1.1 Identification of Causes 15.1.6.1.2 Frequency Classification 15.1.6.2 Sequence of Events and System Operation 15.1.6.2.1 Sequence of Events 15.1.6.2.2 System Operation 15.1.6.2.3 The Effect of Single Failures and Operator Errors 15.1.6.3 Core and System Performance 15.1.6.4 Barrier Performance 15.1.6.5 Radiological Consequences 15.1.7 References 15.2 INCREASE IN REACTOR PRESSURE 15.2.1 Pressure Regulator Failure - Closed 15.2.1.1 Identification of Causes and Frequency Classification 15.2.1.1.1 Identification of Causes 15.2.1.1.2 Frequency Classification 15.2.1.2 Sequence of Events and System Operation 15.2.1.2.1 Sequence of Events 15.2.1.2.2 Systems Operation 15.2.1.2.3 The Effect of Single Failures and Operator Errors 15.2.1.3 Core and System Performance 15.2.1.3.1 Mathematical Model 15.2.1.3.2 Input Parameters and Initial Conditions 15.2.1.3.3 Results 15.2.1.3.4 Consideration of Uncertainties 15.2.1.4 Barrier Performance 15.2.1.5 Radiological Consequences 15.2.2 Generator Load Rejection 15.2.2.1 Identification of Causes and Frequency Classification 15.2.2.1.1 Identification of Causes 15.2.2.1.2 Frequency Classification 15.2.2.2 Sequence of Events and System Operation 15.2.2.2.1 Sequence of Events 15.2.2.2.2 System Operation 15.2.2.2.3 The Effect of Single Failures and Operator Errors 15.2.2.3 Core and System Performance 15.2.2.3.1 Mathematical Model 15.2.2.3.2 Input Parameters and Initial Conditions 15.2.2.3.3 Results 15.2.2.3.4 Consideration of Uncertainties 15.2.2.4 Barrier Performance 15.2.2.4.1 Generator Load Rejection 15.2.2.4.2 Generator Load Rejection with Failure of Bypass 15.2.2.5 Radiological Consequences CHAPTER 15 15-iii REV. 17, SEPTEMBER 2014
LGS UFSAR TABLE OF CONTENTS (cont'd) 15.2.3 Turbine Trip 15.2.3.1 Identification of Causes and Frequency Classification 15.2.3.1.1 Identification of Causes 15.2.3.1.2 Frequency Classification 15.2.3.2 Sequence of Events and System Operation 15.2.3.2.1 Sequence of Events 15.2.3.2.2 System Operation 15.2.3.2.3 The Effect of Single Failures and Operator Errors 15.2.3.3 Core and System Performance 15.2.3.3.1 Mathematical Model 15.2.3.3.2 Input Parameters and Initial Conditions 15.2.3.3.3 Results 15.2.3.3.4 Consideration of Uncertainties 15.2.3.4 Barrier Performance 15.2.3.4.1 Turbine Trip 15.2.3.4.2 Turbine Trip with Failure of the Bypass 15.2.3.5 Radiological Consequences 15.2.4 MSIV Closures 15.2.4.1 Identification of Causes and Frequency Classification 15.2.4.1.1 Identification of Causes 15.2.4.1.2 Frequency Classification 15.2.4.2 Sequence of Events and System Operation 15.2.4.2.1 Sequence of Events 15.2.4.2.2 System Operation 15.2.4.2.3 The Effect of Single Failures and Operator Errors 15.2.4.3 Core and System Performance 15.2.4.3.1 Mathematical Model 15.2.4.3.2 Input Parameters and Initial Conditions 15.2.4.3.3 Results 15.2.4.3.4 Consideration of Uncertainties 15.2.4.4 Barrier Performance 15.2.4.4.1 Closure of All Main Steam Isolation Valves 15.2.4.4.2 Closure of One Main Steam Isolation Valve 15.2.4.5 Radiological Consequences 15.2.5 Loss of Condenser Vacuum 15.2.5.1 Identification of Causes and Frequency Classification 15.2.5.1.1 Identification of Causes 15.2.5.1.2 Frequency Classification 15.2.5.2 Sequence of Events and System Operation 15.2.5.2.1 Sequence of Events 15.2.5.2.2 System Operation 15.2.5.2.3 The Effect of Single Failures and Operator Errors 15.2.5.3 Core and System Performance 15.2.5.3.1 Mathematical Model 15.2.5.3.2 Input Parameters and Initial Conditions CHAPTER 15 15-iv REV. 17, SEPTEMBER 2014
LGS UFSAR TABLE OF CONTENTS (cont'd) 15.2.5.3.3 Results 15.2.5.3.4 Consideration of Uncertainties 15.2.5.4 Barrier Performance 15.2.5.5 Radiological Consequences 15.2.6 Loss of AC Power 15.2.6.1 Identification of Causes and Frequency Classification 15.2.6.1.1 Identification of Causes 15.2.6.1.2 Frequency Classification 15.2.6.2 Sequence of Events and System Operation 15.2.6.2.1 Sequence of Events 15.2.6.2.2 System Operation 15.2.6.2.3 The Effect of Single Failures and Operator Errors 15.2.6.3 Core and System Performance 15.2.6.3.1 Mathematical Model 15.2.6.3.2 Input Parameters and Initial Conditions 15.2.6.3.3 Results 15.2.6.3.4 Consideration of Uncertainties 15.2.6.4 Barrier Performance 15.2.6.4.1 Loss of All Grid Connections 15.2.6.5 Radiological Consequences 15.2.7 Loss of Feedwater Flow 15.2.7.1 Identification of Causes and Frequency Classification 15.2.7.1.1 Identification of Causes 15.2.7.1.2 Frequency Classification 15.2.7.2 Sequence of Events and System Operation 15.2.7.2.1 Sequence of Events 15.2.7.2.2 System Operation 15.2.7.2.3 The Effect of Single Failures and Operator Errors 15.2.7.3 Core and System Performance 15.2.7.3.1 Mathematical Model 15.2.7.3.2 Input Parameters and Initial Conditions 15.2.7.3.3 Results 15.2.7.3.4 Consideration of Uncertainties 15.2.7.4 Barrier Performance 15.2.7.5 Radiological Consequences 15.2.8 Feedwater Line Break 15.2.9 Failure of RHR Shutdown Cooling 15.2.9.1 Identification of Causes and Frequency Classification 15.2.9.1.1 Identification of Causes 15.2.9.1.2 Frequency Classification 15.2.9.2 Sequence of Events and System Operation 15.2.9.2.1 Sequence of Events 15.2.9.2.2 System Operation 15.2.9.2.3 The Effect of Single Failures and Operator Errors CHAPTER 15 15-v REV. 17, SEPTEMBER 2014
LGS UFSAR TABLE OF CONTENTS (cont'd) 15.2.9.3 Core and System Performance 15.2.9.3.1 Methods, Assumptions, and Conditions 15.2.9.3.2 Mathematical Model 15.2.9.3.3 Input Parameters and Initial Conditions 15.2.9.3.4 Results 15.2.9.4 Barrier Performance 15.2.9.5 Radiological Consequences 15.2.10 Loss of Stator Cooling 15.2.10.1 Identification of Causes and Frequency Classification 15.2.10.1.1 Identification of Causes 15.2.10.1.2 Frequency Classification 15.2.10.2 Sequence of Events and System Operation 15.2.10.2.1 Sequence of Events 15.2.10.2.2 System Operation 15.2.10.2.3 The Effect of Single Failures and Operator Errors 15.2.10.3 Core and System Performance 15.2.10.3.1 Mathematical Model 15.2.10.3.2 Input Parameters and Initial Conditions 15.2.10.3.3 Results 15.2.10.3.4 Consideration of Uncertainties 15.2.10.4 Barrier Performance 15.2.10.5 Radiological Consequences 15.2.11 References 15.3 DECREASE IN REACTOR COOLANT SYSTEM FLOW RATE 15.3.1 Recirculation Pump Trip 15.3.1.1 Identification of Causes and Frequency Classification 15.3.1.1.1 Identification of Causes 15.3.1.1.2 Frequency Classification 15.3.1.2 Sequence of Events and System Operation 15.3.1.2.1 Sequence of Events 15.3.1.2.2 System Operation 15.3.1.2.3 The Effect of Single Failures and Operator Errors 15.3.1.3 Core and System Performance 15.3.1.3.1 Mathematical Model 15.3.1.3.2 Input Parameters and Initial Conditions 15.3.1.3.3 Results 15.3.1.3.4 Consideration of Uncertainties 15.3.1.4 Barrier Performance 15.3.1.4.1 Trip of One Recirculation Pump 15.3.1.4.2 Trip of Two Recirculation Pumps 15.3.1.5 Radiological Consequences 15.3.2 Recirculation Flow Control Failure - Decreasing Flow 15.3.2.1 Identification of Causes and Frequency Classification CHAPTER 15 15-vi REV. 17, SEPTEMBER 2014
LGS UFSAR TABLE OF CONTENTS (cont'd) 15.3.2.1.1 Identification of Causes 15.3.2.1.2 Frequency Classification 15.3.2.2 Sequence of Events and System Operation 15.3.2.2.1 Sequence of Events 15.3.2.2.2 System Operation 15.3.2.2.3 The Effect of Single Failures and Operator Errors 15.3.2.3 Core and System Performance 15.3.2.3.1 Mathematical Model 15.3.2.3.2 Input Parameters and Initial Conditions 15.3.2.3.3 Results 15.3.2.3.4 Consideration of Uncertainties 15.3.2.4 Barrier Performance 15.3.2.5 Radiological Consequences 15.3.3 Recirculation Pump Seizure 15.3.3.1 Identification of Causes and Frequency Classification 15.3.3.1.1 Identification of Causes 15.3.3.1.2 Frequency Classification 15.3.3.2 Sequence of Events and System Operation 15.3.3.2.1 Sequence of Events 15.3.3.2.2 System Operation 15.3.3.2.3 The Effect of Single Failures and Operator Errors 15.3.3.3 Core and System Performance 15.3.3.3.1 Mathematical Model 15.3.3.3.2 Input Parameters and Initial Conditions 15.3.3.3.3 Results 15.3.3.3.4 Consideration of Uncertainties 15.3.3.4 Barrier Performance 15.3.3.5 Radiological Consequences 15.3.4 Recirculation Pump Shaft Break 15.3.4.1 Identification of Causes and Frequency Classification 15.3.4.1.1 Identification of Causes 15.3.4.1.2 Frequency Classification 15.3.4.2 Sequence of Events and System Operation 15.3.4.2.1 Sequence of Events 15.3.4.2.2 System Operation 15.3.4.2.3 The Effect of Single Failures and Operator Errors 15.3.4.3 Core and System Performance 15.3.4.4 Qualitative Results 15.3.4.5 Barrier Performance 15.3.4.6 Radiological Consequences 15.4 REACTIVITY AND POWER DISTRIBUTION ANOMALIES 15.4.1 Rod Withdrawal Error - Low Power 15.4.1.1 Control Rod Removal Error During Refueling 15.4.1.1.1 Identification of Causes and Frequency Classification CHAPTER 15 15-vii REV. 17, SEPTEMBER 2014
LGS UFSAR TABLE OF CONTENTS (cont'd) 15.4.1.1.2 Sequence of Events and System Operation 15.4.1.1.3 Core and System Performances 15.4.1.1.4 Barrier Performance 15.4.1.1.5 Radiological Consequences 15.4.1.2 Continuous Rod Withdrawal During Reactor Startup 15.4.1.2.1 Identification of Causes and Frequency Classification 15.4.1.2.2 Sequence of Events and System Operation 15.4.1.2.3 Core and System Performances 15.4.1.2.4 Barrier Performance 15.4.1.2.5 Radiological Consequences 15.4.2 Rod Withdrawal Error - at Power 15.4.2.1 Identification of Causes and Frequency Classification 15.4.2.1.1 Identification of Causes 15.4.2.1.2 Frequency Classification 15.4.2.2 Sequence of Events and System Operation 15.4.2.2.1 Sequence of Events 15.4.2.2.2 System Operation 15.4.2.2.3 The Effect of Single Failures and Operator Errors 15.4.2.3 Core and System Performance 15.4.2.4 Barrier Performance 15.4.2.5 Radiological Consequences 15.4.3 Control Rod Maloperation (System Malfunction or Operator Error) 15.4.4 Startup of Idle Recirculation Pump 15.4.4.1 Identification of Causes and Frequency Classification 15.4.4.1.1 Identification of Causes 15.4.4.2 Sequence of Events and System Operation 15.4.4.2.1 Sequence of Events 15.4.4.2.2 System Operation 15.4.4.2.3 The Effect of Single Failures and Operator Errors 15.4.4.3 Core and System Performance 15.4.4.3.1 Mathematical Model 15.4.4.3.2 Input Parameters and Initial Conditions 15.4.4.3.3 Results 15.4.4.3.4 Consideration of Uncertainties 15.4.4.4 Barrier Performance 15.4.4.5 Radiological Consequences 15.4.5 Recirculation Flow Control Failure with Increasing Flow 15.4.5.1 Identification of Causes and Frequency Classification 15.4.5.1.1 Identification of Causes 15.4.5.1.2 Frequency Classification 15.4.5.2 Sequence of Events and System Operation 15.4.5.2.1 Sequence of Events 15.4.5.2.2 System Operation 15.4.5.2.3 The Effect of Single Failures and Operator Errors CHAPTER 15 15-viii REV. 17, SEPTEMBER 2014
LGS UFSAR TABLE OF CONTENTS (cont'd) 15.4.5.3 Core and System Performance 15.4.5.3.1 Mathematical Model 15.4.5.3.2 Input Parameters and Initial Conditions 15.4.5.3.3 Results 15.4.5.3.4 Consideration of Uncertainties 15.4.5.4 Barrier Performance 15.4.5.5 Radiological Consequences 15.4.6 Chemical and Volume Control System Malfunctions 15.4.7 Misplaced Bundle Accident 15.4.7.1 Identification of Causes and Frequency Classification 15.4.7.1.1 Identification of Causes 15.4.7.1.2 Frequency Classification 15.4.7.2 Sequence of Events and System Operation 15.4.7.2.1 The Effect of Single Failures and Operator Errors 15.4.7.3 Core and System Performance 15.4.7.4 Barrier Performance 15.4.7.5 Radiological Consequences 15.4.8 Spectrum of Rod Ejection Accidents 15.4.9 Control Rod-Drop Accident 15.4.9.1 Identification of Causes and Frequency Classification 15.4.9.2 Sequence of Events and System Operation 15.4.9.3 Core and System Performance 15.4.9.3.1 Mathematical Model 15.4.9.3.2 Input Parameters and Initial Conditions 15.4.9.3.3 Results 15.4.9.4 Barrier Performance 15.4.9.5 Radiological Consequences for the CRDA 15.4.9.5.1 Regulatory Approach 15.4.9.5.2 Dose Acceptance Criteria 15.4.9.5.3 Computer Codes 15.4.9.5.4 Source Terms 15.4.9.5.5 Methodology 15.4.9.5.6 Atmospheric Dispersion Factors (X/Qs) 15.4.9.5.7 Summary and Conclusions 15.4.10 References 15.5 INCREASE IN REACTOR COOLANT INVENTORY 15.5.1 Inadvertent HPCI Startup 15.5.1.1 Identification of Causes and Frequency Classification 15.5.1.1.1 Identification of Causes 15.5.1.1.2 Frequency Classification 15.5.1.2 Sequence of Events and System Operation CHAPTER 15 15-ix REV. 17, SEPTEMBER 2014
LGS UFSAR TABLE OF CONTENTS (cont'd) 15.5.1.2.1 Sequence of Events 15.5.1.2.2 System Operation 15.5.1.2.3 The Effect of Single Failures and Operator Errors 15.5.1.3 Core and System Performance 15.5.1.3.1 Mathematical Model 15.5.1.3.2 Input Parameter and Initial Conditions 15.5.1.3.3 Results 15.5.1.3.4 Consideration of Uncertainties 15.5.1.4 Barrier Performance 15.5.1.5 Radiological Consequences 15.5.2 Chemical Volume Control System Malfunction (or Operator Error) 15.5.3 Other BWR Transients Which Increase Reactor Coolant Inventory 15.6 DECREASE IN REACTOR COOLANT INVENTORY 15.6.1 Inadvertent Main Steam Relief Valve Opening 15.6.2 Instrument Line Pipe Break 15.6.2.1 Identification of Causes and Frequency Classification 15.6.2.1.1 Identification of Causes and Event Description 15.6.2.1.2 Frequency Classification 15.6.2.2 Sequence of Events and System Operation 15.6.2.2.1 Sequence of Events 15.6.2.2.2 System Operation 15.6.2.2.3 The Effect of Single Failures and Operator Errors 15.6.2.3 Core and System Performance 15.6.2.3.1 Qualitative Summary 15.6.2.3.2 Quantitative Results 15.6.2.3.3 Consideration of Uncertainties 15.6.2.4 Barrier Performance 15.6.2.4.1 General 15.6.2.5 Radiological Consequences 15.6.2.5.1 Design Basis Analysis 15.6.2.5.2 Realistic Analysis 15.6.3 Steam Generator Tube Failure 15.6.4 Steam System Piping Break Outside Primary Containment 15.6.4.1 Identification of Causes and Frequency Classification 15.6.4.1.1 Identification of Causes 15.6.4.1.2 Frequency Classification 15.6.4.2 Sequence of Events and System Operation 15.6.4.2.1 Sequence of Events 15.6.4.2.2 System Operation 15.6.4.2.3 The Effect of Single Failures and Operator Errors 15.6.4.3 Core and System Performance CHAPTER 15 15-x REV. 17, SEPTEMBER 2014
LGS UFSAR TABLE OF CONTENTS (cont'd) 15.6.4.3.1 Input Parameters and Initial Conditions 15.6.4.3.2 Results 15.6.4.3.3 Consideration of Uncertainties 15.6.4.4 Barrier Performance 15.6.4.5 Radiological Consequences for the MSLB 15.6.4.5.1 Regulatory Approach 15.6.4.5.2 Dose Acceptance Criteria 15.6.4.5.3 Computer Codes 15.6.4.5.4 Source Terms 15.6.4.5.5 Methodology 15.6.4.5.6 Atmospheric Dispersion Factors (X/Qs) 15.6.4.5.7 Summary and Conclusions 15.6.5 Loss-of-Coolant Accidents (Resulting from Spectrum of Postulated Piping Breaks Within the Reactor Coolant Pressure Boundary) Inside Primary Containment 15.6.5.1 Identification of Causes and Frequency Classification 15.6.5.1.1 Identification of Causes 15.6.5.1.2 Frequency Classification 15.6.5.2 Sequence of Events and System Operation 15.6.5.2.1 Sequence of Events 15.6.5.2.2 System Operation 15.6.5.2.3 The Effect of Single Failures and Operator Errors 15.6.5.3 Core and System Performance 15.6.5.3.1 Mathematical Model 15.6.5.3.2 Input Parameters and Initial Conditions 15.6.5.3.3 Results 15.6.5.3.4 Consideration of Uncertainties 15.6.5.4 Barrier Performance 15.6.5.5 Radiological Consequences for the LOCA 15.6.5.5.1 Regulatory Approach 15.6.5.5.2 Dose Acceptance Criteria 15.6.5.5.3 Computer Codes 15.6.5.5.4 Source Terms 15.6.5.5.5 Methodology 15.6.5.5.6 Atmospheric Dispersion Factors (X/Qs) 15.6.5.5.7 Summary and Conclusions 15.6.6 Feedwater Line Break Outside Primary Containment 15.6.6.1 Identification of Causes and Frequency Classification 15.6.6.1.1 Identification of Causes 15.6.6.1.2 Frequency Classification 15.6.6.2 Sequence of Events and System Operation 15.6.6.2.1 Sequence of Events 15.6.6.2.2 System Operation 15.6.6.2.3 The Effect of Single Failures and Operator Errors 15.6.6.3 Core and System Performance 15.6.6.3.1 Qualitative Summary CHAPTER 15 15-xi REV. 17, SEPTEMBER 2014
LGS UFSAR TABLE OF CONTENTS (cont'd) 15.6.6.3.2 Qualitative Results 15.6.6.3.3 Consideration of Uncertainties 15.6.6.4 Barrier Performance 15.6.6.5 Radiological Consequences 15.6.6.5.1 Design Basis Analysis 15.6.6.5.2 Realistic Analysis 15.6.7 Loss of Feedwater Flow 15.6.8 References 15.7 RADIOACTIVE RELEASES FROM SUBSYSTEMS AND COMPONENTS 15.7.1 Radioactive Gas Waste System Leak or Failure 15.7.1.1 Main Condenser Offgas Treatment System Failure 15.7.1.1.1 Identification of Causes and Frequency Classification 15.7.1.1.2 Sequence of Events and System Operation 15.7.1.1.3 Core and System Performance 15.7.1.1.4 Barrier Performance 15.7.1.1.5 Radiological Consequences 15.7.1.2 Malfunction of Main Turbine Gland Sealing System 15.7.1.2.1 Identification of Causes and Frequency Classification 15.7.1.2.2 Sequence of Events and System Operation 15.7.1.2.3 Core and System Performance 15.7.1.2.4 Barrier Analysis 15.7.1.2.5 Radiological Consequences 15.7.1.3 Failure of Steam Jet Air Ejector Lines 15.7.1.3.1 Identification of Causes and Frequency Classification 15.7.1.3.2 Sequence of Events and System Operation 15.7.1.3.3 Core and System Performance 15.7.1.3.4 Barrier Analysis 15.7.1.3.5 Radiological Consequences 15.7.2 Liquid Radioactive Waste System Failure 15.7.2.1 Identification of Causes and Frequency Classification 15.7.2.1.1 Identification of Causes 15.7.2.1.2 Frequency Classification 15.7.2.2 Sequence of Events and System Operation 15.7.2.3 Core and System Performance 15.7.2.4 Barrier Performance 15.7.2.5 Radiological Consequences 15.7.2.5.1 Design Basis Analysis 15.7.2.5.2 Realistic Analysis 15.7.3 Postulated Radioactive Releases Due to Liquid Radwaste Tank Failure 15.7.4 Fuel Handling Accident 15.7.4.1 Identification of Causes and Frequency Classification CHAPTER 15 15-xii REV. 17, SEPTEMBER 2014
LGS UFSAR TABLE OF CONTENTS (cont'd) 15.7.4.1.1 Identification of Causes 15.7.4.1.2 Frequency Classification 15.7.4.2 Sequence of Events and System Operation 15.7.4.2.1 Sequence of Events 15.7.4.2.2 Identification of Operator Actions 15.7.4.2.3 System Operation 15.7.4.2.4 The Effect of Single Failures and Operator Errors 15.7.4.3 Core and System Performance 15.7.4.3.1 Mathematical Model 15.7.4.3.2 Input Parameters and Initial Conditions 15.7.4.3.3 Results 15.7.4.4 Barrier Performance 15.7.4.5 Radiological Consequences for the FHA 15.7.4.5.1 Regulatory Approach 15.7.4.5.2 Dose Acceptance Criteria 15.7.4.5.3 Computer Codes 15.7.4.5.4 Source Terms 15.7.4.5.5 Methodology 15.7.4.5.6 Atmospheric Dispersion Factors (X/Qs) 15.7.4.5.7 Summary and Conclusions 15.7.5 Spent Fuel Cask-Drop Accident 15.7.6 Movement of Loads Without Secondary Containment 15.7.7 References 15.8 ANTICIPATED TRANSIENTS WITHOUT SCRAM 15.8.1 Requirements 15.8.2 Plant Capabilities 15.8.3 Equipment Description 15.8.3.1 Redundant Reactivity Control System 15.8.3.2 Alternate Rod Insertion 15.8.3.3 Recirculation Pump Trip 15.8.3.4 Feedwater Runback 15.8.3.5 Standby Liquid Control System 15.8.3.6 Scram Discharge Volume 15.8.3.7 HPCI Flow Split Modification 15.8.4 References 15.9 PLANT NUCLEAR SAFETY OPERATIONAL ANALYSIS (A SYSTEM LEVEL/
QUALITATIVE-TYPE PLANT FMEA) 15.9.1 Objectives CHAPTER 15 15-xiii REV. 17, SEPTEMBER 2014
LGS UFSAR TABLE OF CONTENTS (cont'd) 15.9.2 Approach to Operational Nuclear Safety 15.9.2.1 Classification of Plant Events 15.9.2.2 NSOA Development 15.9.2.2.1 Scope and Classification of Plant Events 15.9.2.2.2 Safety and Power Generation 15.9.2.2.3 Frequency of Events 15.9.2.2.4 Conservative Analysis Margins 15.9.2.2.5 Safety Function Definition 15.9.2.2.6 Envelope and Actual Event Analyses 15.9.2.2.7 Analysis Consistency 15.9.2.3 Comprehensiveness of the Analysis 15.9.2.4 Systematic Approach of the Analysis 15.9.2.5 Relationship of Nuclear Safety Operational Analysis to Safety Analyses of Chapter 15 15.9.2.6 Relationship Between NSOA and Operational Requirements, Technical Specifications, Design Bases, and Single Active Component Failure Aspects 15.9.2.7 Unacceptable Consequences Criteria 15.9.2.8 General Nuclear Safety Operational Criteria 15.9.3 Method of Analysis 15.9.3.1 General Approach 15.9.3.2 BWR Operating States 15.9.3.3 Selection of Events for Analysis 15.9.3.3.1 Normal Operations 15.9.3.3.2 Anticipated Operational Transients 15.9.3.3.3 Abnormal Operational Transients 15.9.3.3.4 Design Basis Accidents 15.9.3.3.5 Special Events 15.9.3.4 Applicability of Events to Operating States 15.9.3.5 Guidelines for Event Analysis 15.9.3.6 Steps in an Operational Analysis 15.9.4 Display of Operational Analysis Results 15.9.4.1 General 15.9.4.2 Protection Sequence and Safety System Auxiliary Diagrams 15.9.5 Bases for Technical Specifications 15.9.5.1 Surveillance Test Requirements 15.9.5.2 Limiting Condition for Operation 15.9.5.3 Maximum Allowable Out-of-Service Time 15.9.6 Operational Analyses 15.9.6.1 Safety System Auxiliaries 15.9.6.2 Normal Operations 15.9.6.2.1 General 15.9.6.2.2 Event Definitions 15.9.6.2.3 Required Safety Actions/Related Unacceptable Consequences CHAPTER 15 15-xiv REV. 17, SEPTEMBER 2014
LGS UFSAR TABLE OF CONTENTS (cont'd) 15.9.6.2.4 Operational Safety Evaluations 15.9.6.3 Anticipated Operational Transients 15.9.6.3.1 General 15.9.6.3.2 Required Safety Actions/Related Unacceptable Consequences 15.9.6.3.3 Event Definitions and Operational Safety Evaluations 15.9.6.4 Abnormal Operational Transients 15.9.6.4.1 General 15.9.6.4.2 Required Safety Actions/Related Unacceptable Consequences 15.9.6.4.3 Event Definition and Operational Safety Evaluation 15.9.6.5 Design Basis Accidents 15.9.6.5.1 General 15.9.6.5.2 Required Safety Actions/Unacceptable Consequences 15.9.6.5.3 Event Definition and Operational Safety Evaluations 15.9.6.6 Special Events 15.9.6.6.1 General 15.9.6.6.2 Required Safety Action/Unacceptable Consequences 15.9.6.6.3 Event Definitions and Operational Safety Evaluation 15.9.7 Summary and Conclusions 15.10 ACCIDENT DOSE MODEL DESCRIPTIONS 15.10.1 Offsite Dose Model 15.10.1.1 Total Body Gamma Dose 15.10.1.2 Thyroid Inhalation Dose 15.10.1.3 Beta Skin Dose 15.10.2 Control Room Doses 15.10.2.1 Control Room X/Q Model 15.10.2.2 Control Room Dose Model 15.10.3 References 15.11 PROBABILISTIC RISK ASSESSMENT 15.12 STATION BLACKOUT 15.12.1 Requirements and Limerick Response 15.12.2 Determination of Required Coping Duration 15.12.3 Use of Alternate Ac Source 15.12.4 Assessment of Ability to Cope with a Station Blackout 15.12.4.1 Condensate Inventory for Decay Heat Removal 15.12.4.2 Class 1E Battery Capacity 15.12.4.3 Compressed Gas 15.12.4.4 Effects of Loss of Ventilation CHAPTER 15 15-xv REV. 17, SEPTEMBER 2014
LGS UFSAR TABLE OF CONTENTS (cont'd) 15.12.4.5 Containment Isolation 15.12.4.6 Reactor Coolant Inventory 15.12.5 Procedures for SBO 15.12.6 References Appendix 15A Continuous Control Rod Withdrawal Transient Analysis Appendix 15B Reload Evaluation CHAPTER 15 15-xvi REV. 17, SEPTEMBER 2014
LGS UFSAR CHAPTER 15 - ACCIDENT ANALYSES LIST OF TABLES TABLE TITLE 15.0-1 Summary of Initial Core Transients 15.0-1A Transient Analysis Results at Rerate Power 15.0-2 Input Parameters and Initial Conditions for Initial Core Transients 15.0-2A Input Parameters and Initial Conditions For Rerate Power Transient Analysis 15.0-3 Summary of Accidents 15.0-4 Atmospheric Dispersion Parameters 15.0-5 Required Operating Limit CPR Values for Initial Core Transients 15.0-6 Transients Where Nonsafety-Grade Systems/Components are Actuated During the Course of the Event 15.1-1 Sequence of Events for Inadvertent RHR Shutdown Cooling Operation 15.1-2 Sequence of Events for Loss of Feedwater Heating 15.1-3 Sequence of Events for Feedwater Controller Failure 15.1-4 Sequence of Events for Pressure Regulator Failure 15.1-5 Sequence of Events for Inadvertent Main Steam Relief Valve Opening 15.2-1 Sequence of Events for Turbine-Generator Load Rejection With Bypass 15.2-2 Sequence of Events for Turbine-Generator Load Rejection Without Bypass 15.2-3 Sequence of Events for Turbine Trip with Bypass 15.2-4 Sequence of Events for Turbine Trip Without Bypass 15.2-5 Sequence of Events for MSIV Closure 15.2-6 Typical Rates of Decay for Condenser Vacuum 15.2-7 Sequence of Events for Loss of Condenser Vacuum 15.2-8 Trip Signals Associated with Loss of Condenser Vacuum 15.2-9 Sequence of Events for Loss of Auxiliary Power Transformer 15.2-10 Sequence of Events for Loss of all Grid Connections CHAPTER 15 15-xvii REV. 17, SEPTEMBER 2014
LGS UFSAR LIST OF TABLES (cont'd) 15.2-11 Sequence of Events for Loss of Feedwater Flow 15.2-12 Sequence of Events for Failure of RHR Shutdown Cooling 15.2-13 Input Parameters for Evaluation of Failure of RHR Shutdown Cooling 15.2-14 Significant Initial Conditions and Results for the Generator Load Rejection Without Bypass and EOC-RPT 15.2-15 Sequence of Events for Loss of Stator Cooling 15.3-1 Sequence of Events for Trip of One Recirculation Pump 15.3-2 Sequence of Events for Trip of Both Recirculation Pumps 15.3-3 Sequence of Events for Recirculation Pump Seizure 15.4-1 Sequence of Events for Control Rod Withdrawal Error in Power Range 15.4-2 Intentionally Left Blank 15.4-3 Deleted.
15.4-4 Sequence of Events for Recirculation Flow Control Failure With Increasing Flow 15.4-5 Sequence of Events for Misplaced Bundle Accident 15.4-6 Initial Conditions and Results of Fuel Bundle Loading Error 15.4-7 This was left blank intentionally.
15.4-8 This was left blank intentionally.
15.4-9 This was left blank intentionally.
15.4-10 This was left blank intentionally.
15.4-11 CRDA - Radiological Consequences Key Inputs and Assumptions 15.4-12 X/Q Values for CRDA 15.4-13 CRDA Radiological Consequences Analysis Results 15.5-1 Sequence of Events: Inadvertent HPCI Startup 15.6-1 Sequence of Events for Instrument Line Break 15.6-2 Instrument Line Break Accident: Parameters Tabulated for Postulated Accident Analyses CHAPTER 15 15-xviii REV. 17, SEPTEMBER 2014
LGS UFSAR LIST OF TABLES (cont'd) 15.6-3 Instrument Line Failure: Activity Airborne in Reactor Enclosure 15.6-4 Instrument Line Failure: Activity Released to the Environment 15.6-5 Instrument Line Failure: Activity Airborne in Reactor Enclosure 15.6-6 Instrument Line Break: Activity Released to the Environment 15.6-7 Instrument Line Failure: Radiological Effects 15.6-8 Sequence of Events for Steam Line Break Outside Primary Containment 15.6-9 MSLB - Radiological Consequences Key Inputs and Assumptions 15.6-10 MSLB X/Q Values 15.6-11 MSLB Radiological Consequences Analysis Results 15.6-12 Not Used 15.6-13 Loss-of-Coolant Accident: Personnel Dose Inputs 15.6-14 Loss-of-Coolant Accident: Source Term 15.6-15 Loss-of-Coolant Accident: Containment Parameters 15.6-16 Loss-of-Coolant Accident: Control Room Parameters 15.6-17 Loss-of-Coolant Accident: Removal Inputs 15.6-18 Loss-of-Coolant Accident: Radiological Dose Summary 15.6-19 Loss-of-Coolant Accident: Control Room Dispersion Factors 15.6-20 Loss-of-Coolant Accident: Offsite Dispersion Factors 15.6-21 Deleted 15.6-22 Deleted 15.6-23 Sequence of Events for Feedwater Line Break Outside Primary Containment 15.6-24 Feedwater Line Break Accident: Parameters Tabulated for Postulated Accident Analyses 15.6-25 Feedwater Line Break: Activity Released to the Environment 15.6-26 Feedwater Line Break: Radiological Effects CHAPTER 15 15-xix REV. 17, SEPTEMBER 2014
LGS UFSAR LIST OF TABLES (cont'd) 15.6-27 Loss-of-Coolant Accident: Sequence of Events for Radiological Consequence Analysis 15.7-1 Sequence of Events for Main Condenser Offgas Treatment System Failure 15.7-2 Radioactive Gas Waste System Failure: Parameters Tabulated for Postulated Accident Analyses 15.7-3 Offgas Equipment Failure Release Assumptions: Release Fractions Assumed for Design Basis and Realistic Analysis 15.7-4 Main Condenser Offgas Treatment System Failure (Charcoal Adsorber Vessels): Activity Released to the Environment 15.7-5 Main Condenser Offgas Treatment System Failure (Charcoal Adsorber Vessels): Activity Released to the Environment 15.7-6 Main Condenser Offgas Treatment System Failure (Charcoal Adsorber Vessels): Radiological Effects 15.7-7 Failure of Steam Jet Air Ejector Lines: Parameters Tabulated for Postulated Accident Analyses 15.7-8 Failure of Steam Jet Air Ejector Lines: Activity Released to the Environment 15.7-9(a) Failure of Steam Jet Air Ejector Lines: Radiological Effects 15.7-9(b) Main Condenser Offgas Treatment System Failure: Radiological Effects 15.7-10 Sequence of Events: Liquid Radwaste Tank Failure 15.7-11 Liquid Radwaste Tank Failure: Parameters Tabulated for Postulated Accident Analyses 15.7-12 Liquid Radwaste Tank Failure (RWCU Phase Separator): Activity Released to the Environment 15.7-13 Liquid Radwaste Tank Failure (RWCU Phase Separator): Activity Released to the Environment 15.7-14 Liquid Radwaste Tank Failure (RWCU Phase Separator): Radiological Effects 15.7-15 Sequence of Events for Fuel Handling Accident 15.7-16 FHA - Radiological Consequences Key Inputs and Parameters 15.7-17 FHA X/Q Values CHAPTER 15 15-xx REV. 17, SEPTEMBER 2014
LGS UFSAR LIST OF TABLES (cont'd) 15.7-18 FHA Radiological Consequences Analysis Results 15.7-19 Not Used 15.7-20 Not Used 15.7-21 Not Used 15.7-22 Potential Energy of Light Loads to be Handled Over Spent Fuel 15.9-1 Normal Operation 15.9-2 Anticipated Operational Transients 15.9-3 Abnormal Operational Transients 15.9-4 Design Basis Accidents 15.9-5 Special Events 15.9-6 Unacceptable Consequences Criteria - Plant Event Category - Normal Operation 15.9-7 Unacceptable Consequences Criteria - Plant Event Category - Anticipated Operational Transients 15.9-8 Unacceptable Consequences Criteria - Plant Event Category - Abnormal Operational Transients 15.9-9 Unacceptable Consequences Criteria - Plant Event Category - Design Basis Accidents 15.9-10 Unacceptable Consequences Considerations - Plant Event Category -
Special Events 15.9-11 BWR Operating States 15.10-1 Physical Data for Isotopes 15.10-2 Accident Atmospheric Dilution Factors - X/Q 15.10.3 Breathing Rates for Offsite Dose Calculations CHAPTER 15 15-xxi REV. 17, SEPTEMBER 2014
LGS UFSAR CHAPTER 15 - ACCIDENT ANALYSES LIST OF FIGURES FIGURE TITLE 15.0-1 Typical Power/Flow Map 15.0-2 Scram Position and Reactivity Characteristics 15.0-3 Minimum Operating CPR Limits versus Scram Speed 15.1-1 Feedwater Controller Failure Without Turbine Bypass 15.1-2 Intentionally Left Blank 15.1-3 Feedwater Controller Failure, Maximum Demand, with High Level Turbine Trip 15.1-4 Pressure Regulator Failure Open 15.2-1 Generator Load Rejection, Trip Scram, Bypass - On, RPT - On 15.2-2 Generator Load Rejection without Bypass 15.2-3 Turbine Trip, Trip Scram, Bypass - On, RPT - On 15.2-4 Turbine Trip without Bypass, Trip Scram 15.2-5 Three Second Closure of all Main Steam Line Isolation Valves 15.2-6 Loss of Condenser Vacuum 15.2-7 Loss of Auxiliary Power Transformer 15.2-8 Loss of All Grid Connections 15.2-9 Loss of All Feedwater Flow 15.2-10 Summary of Paths Available to Achieve Cold Shutdown 15.2-11 Use of ADS and RHR Suppression Pool Cooling to Achieve Cold Shutdown 15.2-12 Vessel Temperature and Pressure versus Time to Achieve Cold Shutdown with ADS and RHR Suppression Pool Cooling 15.2-13 Suppression Pool Temperature versus Time to Achieve Cold Shutdown with ADS and RHR Suppression Pool Cooling CHAPTER 15 15-xxii REV. 17, SEPTEMBER 2014
LGS UFSAR LIST OF FIGURES (cont'd) 15.2-14 Generator Load Rejection, No Bypass, No EOC-RPT 15.3-1 Trip of One Recirculation Pump Motor 15.3-2 Trip of Both Recirculation Pump Motors 15.3-3 Seizure of One Recirculation Pump 15.4-1 This figure has been deleted.
15.4-2 Deleted 15.4-3 Recirculation Failure - Increasing Flow 15.4-4 Deleted 15.5-1 Inadvertent Startup of HPCI Pump 15.6-1 Leakage Path for Instrument Line Break 15.6-2 Steam Flow Schematic for Steam Break Outside Primary Containment 15.6-3 Leakage Flow for LOCA 15.6-4 Leakage Path for Feedwater Line Break Outside Primary Containment 15.7-1 Leakage Path for Fuel Handling Accident 15.9-1 Block Diagram of Method Used to Derive Nuclear Safety Operational Requirements System, Level Qualitative FMEA, Design Basis Confirmation Audits, and Technical Specifications 15.9-2 Possible Inconsistencies in the Selection of Nuclear Safety Operational Requirements 15.9-3 INTENTIONALLY LEFT BLANK 15.9-4 Format for Protection Sequence Diagrams 15.9-5 Format for Safety System Auxiliary Diagrams 15.9-6 INTENTIONALLY LEFT BLANK 15.9-7 Safety System Auxiliaries 15.9-8 Safety System Auxiliaries 15.9-9 Safety Action Sequences for Normal Operation in State A 15.9-10 Safety Action Sequences for Normal Operation in State B 15.9-11 Safety Action Sequences for Normal Operation in State C CHAPTER 15 15-xxiii REV. 17, SEPTEMBER 2014
LGS UFSAR LIST OF FIGURES (cont'd) 15.9-12 Safety Action Sequences for Normal Operation in State D 15.9-13 Protection Sequence for Manual or Inadvertent Scram 15.9-14 Protection Sequences for Loss of Plant Instrument and Service Air System 15.9-15 Protection Sequences for Inadvertent Startup of NSSS Pump 15.9-16 Protection Sequences for Inadvertent Startup of Idle Recirculation Loop Pump 15.9-17 Protection Sequence for Recirculation Loop Flow Control Failure (Increasing Flow) 15.9-18 Protection Sequence for Recirculation Loop Flow Control Failure (Decreasing Flow) 15.9-19 Protection Sequences for Recirculation Loop Pump Trip (One or Both) 15.9-20 Protection Sequences for Isolation of All Main Steam Lines 15.9-21 Protection Sequences for Isolation of One Main Steam Line 15.9-22 Protection Sequences for Inadvertent Opening of an MSRV 15.9-23 Protection Sequence for Control Rod Withdrawal Error for Startup and Refueling Operations 15.9-24 Protection Sequence for Control Rod Withdrawal Error - Power Operation 15.9-25 Protection Sequences for RHR - Loss of Shutdown Cooling 15.9-26 Protection Sequences for RHR (Shutdown Cooling) Increased Cooling 15.9-27 Protection Sequences for Loss of Feedwater Flow 15.9-28 Protection Sequence for Loss of a Feedwater Heater 15.9-29 Protection Sequences for Feedwater Controller Failure (Maximum Demand) 15.9-30 Protection Sequences for Pressure Regulator Failure (Open) 15.9-31 Protection Sequences for Pressure Regulator Failure (Closed) 15.9-32 Protection Sequences for Main Turbine Trip with Bypass System Operation 15.9-33 Protection Sequences for Loss of Main Condenser Vacuum CHAPTER 15 15-xxiv REV. 17, SEPTEMBER 2014
LGS UFSAR LIST OF FIGURES (cont'd) 15.9-34 Protection Sequences for Main Generator Trip with Bypass System Operation 15.9-35 Protection Sequences for Achieving Shutdown Cooling with Reactor Vessel Isolated 15.9-36 Protection Sequences for Loss of Normal Ac Power (Grid Connection Loss) 15.9-37 Protection Sequences for Main Generator Trip With Bypass System Failure 15.9-38 Protection Sequences for Main Turbine Trip With Bypass System Failure 15.9-39 Protection Sequence for Inadvertent Loading and Operation of Fuel Assembly in Improper Position 15.9-40 Protection Sequences for Recirculation Loop Pump Seizure 15.9-41 Protection Sequences for Recirculation Pump Shaft Break 15.9-42 Protection Sequences for Control Rod-Drop Accident 15.9-43 Protection Sequences for Fuel Handling Accident 15.9-44 Protection Sequences for Loss of Coolant Piping Breaks in RCPB Inside Containment 15.9-45 Protection Sequences for Piping Breaks Outside Containment 15.9-46 Protection Sequences for Gaseous Radwaste System Leak or Failure 15.9-47 Protection Sequences for Augmented Offgas Treatment System Failure 15.9-48 Protection Sequences for Liquid Radwaste System Leak or Failure 15.9-49 Protection Sequences for Liquid Radwaste System - Storage Tank Failure 15.9-50 Protection Sequences for Shipping Cask Drop 15.9-51 Protection Sequences for Reactor Shutdown/ATWS 15.9-52 Protection Sequences for Reactor Shutdown From Outside Control Room 15.9-53 Protection Sequences for Reactor Shutdown Without Control Rods CHAPTER 15 15-xxv REV. 17, SEPTEMBER 2014