Part of the president’s energy plans also calls for the construction of the country’s fist new nuclear plants in a generation. The proposal comes as the world marks the 19th anniversary of the worst ever nuclear disaster at Chernobyl. A leading Russian scientist warned this week that a second disaster looms in Chernobyl because of cracks in the reactor’s decaying shell. If the shell collapsed it could cause a catastrophe on the same scale as the original accident almost 20 years ago.