ABSTRACT
This chapter summarizes the TMI-2 Accident Evaluation Program that is being conducted for the US Department of Energy and briefly describes the important results that have been achieved. The Program is divided into four parts: Sample Acquisition and Plant Examination, Accident Scenario, Standard Problem Exercise, and Information and Industry Coordination. Because of decreasing liquid inventory in the primary cooling system and continued heating by decay heat in the fuel, coolant void fraction increased sufficiently over the next hour to cause the reactor pumps to vibrate excessively from cavitation. To help achieve the maximum benefit of the lessons learned from the accident, the AEP includes a special task to collect, organize, and disseminate information about the accident and the results of the plant examinations and analyses to the world nuclear community, the news media, and other interested persons. The accident at Three Mile Island Unit 2 resulted in severe fuel damage, much beyond that expected to occur during design-basis accidents.
