Fire breaks out again at Fukushima’s No. 4 reactor: TEPCO

Fire breaks out again at Fukushima’s No. 4 reactor: TEPCO
# 16 March 2011 04:12 (UTC +04:00)
The fire came a day after a blast caused a blaze at the reactor, where it is feared spent nuclear fuel may be exposed, posing the risk of leaks of high-level radioactive materials.

TEPCO, the plant operator, also said an estimated 70 percent of the nuclear fuel rods have been damaged at the plant’s No. 1 reactor and 33 percent at the No. 2 reactor.

The cores of both reactors are believed to have partially melted with their cooling functions lost in the wake of Friday’s magnitude 9.0 earthquake.

Around 5:45 a.m., a worker at the plant saw flames on the fourth floor of the building housing the No. 4 reactor, believed to be the same spot where an apparent hydrogen explosion caused a fire at 9:38 a.m. Tuesday. The reactor had been halted for regular checks from before the quake.

TEPCO said it had stopped fire-fighting operations after judging that the Tuesday morning fire had been extinguished. It said it promptly reported the latest incident to firefighters and local governments.

Flames were seen through the two square-shaped holes about 8 by 8 meters created in the walls of the building by Tuesday’s 6:14 a.m. blast, but were no longer visible when workers at the plant tried to confirm them at 6:15 a.m. Wednesday, the utility said.

On Tuesday, the utility said water in a pool storing spent nuclear fuel rods at the reactor may be boiling and that its level may have dropped, exposing the rods. The government ordered the firm to inject water into the pool ’’as soon as possible to avert a major nuclear disaster.’’

Unless the spent fuel rods are cooled down, they could suffer damage and emit radioactive substances.