Issue 79: Unanalyzed Reactor Vessel Thermal Stress During Natural Convection Cooldown
DESCRIPTION
Historical Background
On March 18, 1983, B&W expressed[1]concern for unanalyzed reactor vessel thermal stress
Issue 78: Monitoring of Fatigue Transient Limits for Reactor Coolant System
DESCRIPTION
Historical Background
STS for newer OLs require licensees to keep account of the number of transient occurrences to ensure that transient limits, based on design assumptions, are not exceeded.
Issue 77: Flooding of Safety Equipment Compartments by Back-Flow Through Floor Drains
DESCRIPTION
Historical Background
On November 11, 1981, the DAILY REPORT-REGION I carried a "prompt report" from Calvert Cliffs Units 1 and 2 indicating the licensee had been notified th
Issue 76: Instrumentation and Control Power Interactions
DESCRIPTION
Historical Background
This issue was identified[1]when a number of concerns regarding DC power systems were raised
Issue 75: Generic Implications of ATWS Events at the Salem Nuclear Plant
DESCRIPTION
Historical Background
On two occasions (February 22 and 25, 1983), Salem Unit 1 failed to scram automatically due to failure of both reactor trip breakers to open on receipt
Issue 74: Reactor Coolant Activity Limits for Operating Reactors
DESCRIPTION
Historical Background
This issue was raised[1]by DSI in June 1983 and addresses the concern that several operating PWRs and BWRs either lack iodi
Issue 73: Detached Thermal Sleeves
DESCRIPTION
Historical Background
During the period 1978 to 1980, there were reports of fatigue failure of thermal sleeve assemblies in the piping systems of both PWRs and BWRs.
Issue 72: Control Rod Drive Guide Tube Support Pin Failures
DESCRIPTION
Background
This issue was raised in Board Notification No.
Issue 70: PORV and Block Valve Reliability
DESCRIPTION
Historical Background
PORVs and block valves were originally designed as non-safety components in the reactor pressure control system for use only when plants are in operatio