Precursors to potential severe core damage accidents, 1986: A status report: Appendixes D, E, and F

Reactor plant operational events for 1986 were selected for documentation as precursors to potential severe core damage based on the selection criteria described in this report. These events are documented here. For each precursor, a precursor description sheet and a conditional core-damage calculation are included. The precursor description sheet briefly describes the event sequence, provides plant and event data pertinent to the evaluation, and documents the modeling considerations and decisions made. Included with the conditional core-damage calculations are individual sequences probabilities for the more significant core-damage (CD), core-vulnerability (CV), and anticipated-transient-without-scram (ATWS) sequences; identification of dominant sequences for each end state; and a listing of the branch probabilities and frequencies utilized. Individual sequences were lised if their probability was >0.03 times the probability of the dominant sequence for each end state. Licensee event reports associated with the precursors and operational event listings are also provided.