Recent events have renewed long-standing congressional interest in safe management of spent nuclear fuel (SNF) and other high level nuclear waste. These issues have been examined and debated for decades, sometimes renewed by world events like the 9/11 terrorist attacks. The incident at the Fukushima Dai-ichi nuclear reactor complex in Japan, combined with the termination of the Yucca Mountain geologic repository project, have contributed to the increased interest. This book focuses on the current situation with spent nuclear fuel storage in the United States. It addresses the SNF storage situation, primarily at current and former reactor facilities and former reactor sites for the potentially foreseeable future. Although no nation has yet established a permanent disposal repository for SNF and other forms of high-level radioactive waste, there is broad consensus that a geological repository is the preferred method for these wastes.