A Nuclear Regulatory Commission task force has called for tightening safety regulations at the nation’s 104 nuclear powerplants and requiring plants to make upgrades when necessary, in areas such as seismic protection, electric power and cooling water for spent-fuel pools. Related Links: NRC task force report In a 90-day report released on July 13, the NRC panel concludes that a sequence of events like those following the Japanese accident is “unlikely to occur” in the United States. Still, the existing U.S. regulatory approach, developed piece by piece over decades, is a “patchwork,” and needs to be improved, the task force
Arch dams, classically curved monoliths situated in narrow valleys, are not as common as other types of dams, such as embankment dams and gravity dams. ENR takes a look at some of the biggest arch dams in the world, both completed and under construction.