U.S. side eyed blasting hole in reactor

Kyodo

An informal panel of experts in the U.S. Department of Energy discussed using military explosives to bring the crisis at the Fukushima No. 1 nuclear plant under control, said panel member and physicist Richard Garwin, who pitched the idea.

“I wanted to make a hole through the great shielding slabs, which are more than a meter of reinforced concrete, and one of the opportunities was to use the military shaped charge,” Garwin said in a telephone interview, referring to the proposal he made to Energy Secretary Steven Chu at the panel meeting last April 5.

Although the idea was not adopted, such an extraordinary proposal of using a shaped charge, an explosive shaped to focus the blast energy in one direction, reflected the sense of alarm within the U.S. government that the situation at the Fukushima complex would worsen if the cooling system failed.

Garwin proposed using a shaped charge containing gunpowder from a distance of 1 meter from the surface of the concrete encasing the nuclear vessel. Such a blast would create a hole about 5 cm in diameter, through which a tube could be inserted from the outside to cool the pressure vessel containing the melted fuel.

“It was not a matter of decision but a matter of selection and analysis” at the department’s laboratories as “the reactor pressure vessel was not being cooled very well,” Garwin said.

He said he also suggested another method of using a high-pressure water jet with abrasive powder to bore a hole through the concrete wall.