Japan Nuclear Agency: Top Priority Is To Pour Water Into No. 3, No. 4 Reactors

Japan 's nuclear plant regulator said Wednesday the top priority now is to pump water into the No. 3 and No. 4 reactors in the quake-stricken plants in northern Japan to keep spent nuclear fuel stored in them from emitting radiation.

Water inside the two troubled reactors in the Dai-ichi Fukushima plant are likely boiling, as indicated by vapor-like white smoke coming out of the No. 3 reactor, an official at the Nuclear and Industrial Safety Agency said at a press briefing.

"It is our top priority to address problems concerning the water pools for spent fuel," he said.

Conditions of the spent-fuel pools are luring increasing attention as Japan 's worst nuclear-plant crisis continues. If used nuclear fuel rods---which tend to grow hotter on their own without coolant water--were left heating up, they could eventually melt and spat out deadly radiation into the air, according to officials from the agency.

Tokyo Electric Power Co., the operator of the Fukushima complex, may consider using a helicopter to drop water on the No. 3 reactor if conditions are good enough to safely carry out such operations, the first official said.

He added that the No. 3 reactor's pressure containment vessel, one of the key layers surrounding the fuel room, is unlikely to have suffered damage, as a sharp rise in radiation levels recorded around noon near the complex was short lived.