TOKYO - Japan saw some success in its race to avert disaster at a tsunami-damaged power plant, though minor radiation leaks underlined perils from the world's worst nuclear crisis since Chernobyl 25 years ago. Three hundred engineers have been battling inside a danger zone to salvage the six-reactor Fukushima plant since it was hit by an earthquake and tsunami that also killed 7,653 people and left 11,746 more missing in northeast Japan. The unprecedented multiple crisis will cost the world's third largest economy nearly $200 billion and require Japan's biggest reconstruction push since post-World War II. It has also set back nuclear power plans the world over. Encouragingly for Japanese transfixed on work at the Fukushima complex, the most critical reactor - No. 3 which has highly toxic plutonium - stabilized after fire trucks doused it for hours with hundreds of metric tons of water. Work also advanced on bringing power back to water pumps used to cool overheating nuclear fuel. "We are making progress ... (but) we shouldn't be too optimistic," said Hidehiko Nishiyama, deputy-general at Japan's Nuclear Safety Agency. Technicians attached a power cable to the No. 1 and No. 2 reactors, hoping to restore electricity later in the day prior to an attempt to switch the pumps on. They aim to reach No. 3 and 4 soon after that. If successful, that could be a turning point in a crisis classed as bad as America's 1979 Three Mile Island accident. If not, drastic measures may be required such as burying the plant in sand and concrete as happened at Chernobyl after the world's worst nuclear reactor disaster in 1986. Facing criticism of its early handling of the situation, plant operator TEPCO's president issued a public apology for "causing such great concern and nuisance". Even after restoring power, the company faces a tricky task reactivating the cooling pumps, with parts of the system probably damaged from the quake or subsequent explosions. "The workers need to go through the plant, figure out what survived and what didn't, what can be readily repaired and get the cooling systems back up and running to deal with the cores and the spent fuel pools," said David Lochbaum, of US nuclear watchdog the Union of Concerned Scientists.
