Nuclear Meltdown

Fuel rods damaged at reactor's 1 and 2

(Xinhua)
Updated: 2011-03-16 13:45

TOKYO - Tokyo Electric Power Co (TEPCO) said early on Wednesday that a fire had broken out at the same reactor building as the scene of a blaze Tuesday at the troubled Fukushima No 1 nuclear power plant where high amounts of radiation have been detected.

According to the plant's officials, the fire was spotted at 05: 45 am local time at the northwestern corner of the building that houses the No 4 reactor.

Special coverage: Earthquake Hits Japan Related readings:  Japan suspends work at stricken nuclear plant  Fukushima No 3 reactor's container feared damaged  Engineer quitted 35 yrs ago over reactor design

Although half an hour following the first sighting of flames, the blaze could no longer be seen the utility said.

TEPCO said they are concerned as the location of the blaze was the same place at which instruments that adjust the speed of a pump sending cooling water to the reactor are located.

The company said that their workers could not get any closer to inspect the instruments because the radiation level remains high there.

TEPCO added that it may spray boric acid by helicopter into the reactor in an effort to prevent the reactor's spent nuclear fuel rods from reaching criticality again and restarting a lethal nuclear chain reaction.

The cause of the fire remains unclear at this point a spokesperson for TEPCO said Wednesday, adding that the fire apparently went out of its own accord.

The No 4 Reactor was undergoing checks at the time of Friday's quake and was not operating, TEPCO said, adding that but they have been having problems cooling down a storage pool for spent nuclear fuel rods inside the building.

On Tuesday, the utility said water in a pool storing the spent fuel rods may be boiling and that the level may have dropped exposing the fuel rods.

The government ordered TEPCO to inject seawater into the pool immediately to avert a nuclear catastrophe, however dangerous levels of radiation around the reactor have prevented workers from pouring water into the faltering pool.

Subsequently, the utility pulled 730 of the 800 workers from the stricken site.

"The possibility of recriticality is not zero," TEPCO said Wednesday, as it announced the planned step to control the situation and cool the rods using boric acid.

Unless the rods are sufficiently cooled, they could melt and release harmful radioactive substances.

At the plant's No 1 reactor TEPCO said 70 percent of the fuel rods have been damaged as have 33 percent of the rods at its No 2 reactor.

Both reactors are believed to have undergone a partial meltdown following critical cooling functions being knocked out following Friday's massive quake and ensuing tsunami, the utility said.