Japan steps up efforts to cool reactors at quake-hit N-plant

Fukushima/Tokyo: Japan on Thursday intensified efforts to cool overheating reactors at its quake-crippled Fukushima nuclear plant, with military choppers dumping tonnes of water in an attempt to prevent a meltdown of fuel rods which could emit highly contaminated radioactive material.

Two CH-47 helicopters of the Self-Defense Force (SDF) scooped up sea water and released it over the reactors after another chopper checked radiation levels in the air, a week after the magnitude-9 quake and devastating tsunami rocked the country leaving 14,650 people dead or unaccounted for.

Today`s mission was part of efforts to cool the storage pools at the No.3 and No.4 reactors, whose cooling systems were not functioning, raising fears that spent fuel rods could melt and release radioactive material outside the building, national broadcaster NHK reported.

The choppers dumped four loads before leaving the site.

Yesterday, they were forced to abort a similar operation due to concerns over high radiation levels.

The unprecedented operation is expected to gain force on the ground soon as Tokyo police prepared to spray water with water cannon truck, with the focus of the nuclear crisis shifting to the pools storing spent fuel rods at each of the plant`s six reactors, located outside the steel containment vessels for enclosing toxic radioactive substances.

The government`s Nuclear and Industrial Safety Agency said the first priority should be pouring water into the pools at the No.3 and No.4 reactors, which may be boiling and are not fully covered by roofs, that would reduce any radiation leaks, Kyodo news agency reported. The two reactors were rocked by explosions earlier this week.

A rise in the temperature, usually at 40C, causes water to reduce and expose the spent nuclear fuel rods, which could heat up further and melt, and discharge highly intense radioactive material in the worse case, experts said.

Also, the US military is poised to operate a Global Hawk unmanned high-altitude reconnaissance aircraft to take images of the inside of the building that houses the No.4 reactor, Japanese government sources were quoted as saying by Kyodo.

Although the No.1, No.2 and No.3 reactors that were operating at the time of the quake halted automatically with jolts, their cores are believed to have melted as they lost cooling functions in an ensuing tsunami.

An estimated 70 per cent of the nuclear fuel rods had been damaged at the No.1 reactor and 33 per cent at the No. 2 reactor, Tokyo Electric Power Company (TEPCO), the operator of the plant, said.

The water level also dropped in the fuel pool at the No.5 reactor, posing the risk of overheating, according to the nuclear safety agency. The No.4, No.5 and No.6 reactors have had fuel rods taken out of their cores for regular checks.

Police put at 14,650 the number of those killed or unaccounted for in last Friday`s quake and tsunami.

The number of confirmed dead climbed to 5,321, while the official number of missing touched 9,329, the National Police Agency (NPA) said. A total of 2,383 people were injured.

However, in Ishinomaki, Miyagi prefecture, Mayor Hiroshi Kameyama told a municipal task force meeting that the number of missing people in the city of 160,000 was estimated to reach 10,000.

According to NPA, 2,000 recovered bodies were identified in Iwate, Miyagi and Fukushima prefectures this morning, out of which 870 were handed over to their families.

In the severely-hit coastal city of Rikuzentakata in Iwate prefecture, the rubble removal work picked up pace, enabling the SDF to build roads so that rescue workers could search for victims across wider areas.

Mayor Futoshi Toba said, "There were some areas where we could not enter, but now we can go anywhere (in the city) by car." He, however, said, "We need fuels to heat, activate heavy machines and deliver relief goods to shelters, but we face difficulties."

Sendai airport, which was submerged by a giant tsunami wave following the quake, reopened a part of its runway for use by police and SDF planes to transport relief material. It has not been decided when the commercial flights will resume.

Express bus lines between Sendai and Morioka as well as Morioka and Aomori were resumed today, connecting all of the six prefectural capitals, including Akita, Yamagata and Fukushima, in the Tohoku region, Kyodo said.

In another heavily-damaged coastal city of Ofunato in Iwate prefecture, elementary as well as junior and senior high schools reopened for the first time since the massive quake struck the region.

At the prefecture-run Ofunato High School, around 250 students arrived on foot or by bicycle. Ayumi Urashima, a 16-year-old student, was quoted as saying by Kyodo that "on the way to school, I met one of my friends who I had not been able to contact. We hugged each other."

In an unprecedented televised address, Emperor Akihito yesterday told the grief-stricken Japanese people that he was saddened by the devastation caused by the quake and tsunami.

"I am deeply hurt by the grievous situation in the disaster-hit areas," he said. "I sincerely hope that people will overcome this unfortunate time by engendering a sense of caring for other people."

Amid increasing concerns about radiation exposure, the US asked its nationals within 50-mile radius of Japanese nuclear power plants to evacuate.

"Those American citizens who are within a 50-mile radius of the reactors evacuate from that area," White House Press Secretary Jay Carney said, after US President Barack Obama was briefed on the current situation in Japan by his national security team, including the Nuclear Regulatory Commission Chairman Gregory Jackzo.