Year
2014
Abstract
After the September 11, 2001 terrorist attacks, the risk of ra diological sabotage of spent fuel pools became an issue of public concern. Also, the March 2011 Fukushima Daiichi accident reminded the world of the disruption to people's lives and property that can result from a release of cesium - 137 to the environment. A rapid loss of cooling water from a spent fuel pool, whether caused by a severe natural catastrophe or a terrorist attack, could potentially release far more cesium - 137 into the environment than the damaged Fukushima Daiichi plants did . Yet the Nuclear Re gulatory Commission has refused to order nuclear plants in the United States to thin out densely packed spent fuel pools by transferring more fuel to dry casks. Such a requirement could reduce the risk of a zirconium fire that could lead to a hydrogen expl osion and significant radionuclide release. However, the NRC argues that expedited spent fuel transfer is not necessary because the likelihood of an accident severe enough to cause such an event is very low and that such accidents can be effectively mitiga ted in any event. It also argues that the measures it required after September 11, including means to provide emergency makeup cooling to spent fuel pools in the event of an aircraft attack, coupled with physical protection requirements, are sufficient to alleviate the risk of spent fuel sabotage. This paper argues that the NRC's position does not take into account the additional defense - in - depth expedited transfer could provide to cope with large uncertainties in its assessments of severe accident and sabo tage risks.