`Japan nuke reactors` pressure vessels punctured`

A Tokyo Electric Power Corp. source said Monday that pressure vessels in nuclear reactors Nos. 1 and 3 at Fukushima Nuclear Power Plant 1 are believed to have punctures.

The corporation previously admitted that nuclear fuel rods were damaged by the overheating of nuclear reactors, but denied damage to pressure vessels. A pressure vessel is a core sealing device that blocks radioactive materials from leaking, and if punctured, radioactive damage could become uncontrollable.

In a news conference Monday evening, a corporation source said, “Pressure vessels Nos. 1 to 3 were damaged and open to the air. You can imagine images of pressure vessels with punctures,” adding, “Water has not been filled to capacity in nuclear reactors despite efforts to inject water perhaps because pressure vessels have punctures.”

If the 16-centimeter thick pressure vessels have punctures, melted nuclear fuel could have fallen into the bottom of the vessels to form a puncture or the inner wall of the vessels could have melted, the corporation said.

Japanese nuclear authorities say they have no choice but to continue injecting water to cool down the reactors. If pressure vessels are damaged, they cannot prevent high-density, radiation-contaminated water from constantly leaking.

The power corporation also said Sunday that the level of radioactive iodine 134 in water contained in turbine room of reactor No. 2 reached 2.9 billion becquerels, or 10 million times the normal level. It issued a correction Monday morning that the level of cesium 134 was found to be 29 million becquerels, 100,000 times the normal level.

changkim@donga.com