New quake reported off Honshu

TOKYO, April 14 (UPI) -- Japan's quake-ruined Honshu Island was hit by a 6.1-magnitude offshore temblor Thursday, the U.S. Geological Survey said.

As workers toil to end the crisis at the Fukushima Daiichi nuclear power plant on the island while facing unrelenting aftershocks, the latest of those shocks off the east coast, 333 miles northeast of Tokyo, struck at 5:57 a.m., the U.S. Geological Survey said. There were no immediate reports of damage locally or at the power plant.

No tsunami warning was issued.

The severity of the crisis at the six-reactor Fukushima plant, 140 miles north of Tokyo, was raised this week from level 5 to the maximum level 7, bringing it on par with the world's worst nuclear disaster, which hit the Chernobyl power plant in Ukraine in 1986. However, Japanese officials have said the Fukushima plant's radioactive emissions are only about 10 percent of what resulted from Chernobyl.

It was a horrific tsunami on the heels of a 9-magnitude earthquake on March 11 that not only triggered the nuclear crisis but also killed at least 13,300 people, left another 15,000 missing and inflicted an estimated $300 billion in economic damage on a country just beginning to enjoy a recovery after years of crippling deflation.

Fukushima plant operator Tokyo Electric Power confirmed Wednesday some of the 1,331 stored spent nuclear fuel rods in the No. 4 reactor building had been damaged but most were believed to be in sound condition, Kyodo News reported.

That confirmation came after the utility's analysis of water from the reactor's spent nuclear fuel pool showed higher levels of radioactive iodine-131, cesium-134 and cesium-137. The No. 4 reactor had been idled prior to March 11 for regular inspection, which required storing both its spent and new fuel rods in its pool. The quake and tsunami, however, may have caused the fuel to overheat, thus damaging the rods, which in turn raised the levels of radioactive materials caused by nuclear fission.

The No. 4 reactor building lost its roof and some of its upper walls in a hydrogen explosion and fires in the March 11 disaster. Explosions also badly damaged the No. 1, 2 and 3 reactors.

Earlier, Tokyo Electric had estimated 25 percent to 70 percent of the nuclear fuel rods in the Nos. 1, 2 and 3 reactors may have been damaged.

The utility said the fuel rods may also have been damaged by steel frames falling into the pool already without its cooling function. It planned to deploy a small unmanned helicopter to see if the damaged rods can be extracted.

The urgent task for the workers is to remove highly radioactive water collecting in the basements of the reactors.

Kyodo News said workers have pumped out 700 tons of the estimated 60,000 tons of the highly contaminated water from an underground trench into a condenser. Once all the contaminated water is removed, which may take weeks, the next task would be to store the tanks.

In other developments, the Health Ministry said radioactive cesium 25 times over the legal limit was found Wednesday in young sand lance fish off Fukushima prefecture, Kyodo News reported.

In an interview to Kyodo News, the vice chairman of the Japan Atomic Energy Commission urged a thorough investigation of the crisis by an independent panel that could include outside experts to ensure openness and transparency with verification by the international community.

CNN reported the president of Tokyo Electric has announced efforts with the government to provide short-term compensation to those affected by the nuclear crisis. His comments came after Japanese Prime Minister Naoto Kan assured no expense would be spared to bring an end to the crisis.