China is drawing up plans to use nuclear explosions, in violation of the Comprehensive Test Ban Treaty, to blast a 10-mile tunnel through the Himalayas in order to build the world’s largest hydroelectric plant. Work on the project, which is expected to produce more than twice as much power as the controversial Three Gorges Dam now being built, would begin after 2009. Meanwhile, Chinese officials defended the Three Gorges project yesterday, insisting that construction and the necessary resettlement of more than 1.1 million people are proceeding smoothly, despite stolen and misused funds. China, determined to divert water from its wet south and west to its drought-stricken north, is on a dam-building spree; the nation has constructed more dams in the past 30 years than the rest of the world’s countries combined and it has many more on the drawing board.