More than 300 workers are racing to prevent a meltdown and spread of radiation at the crippled Fukushima Dai-Ichi power station today, an increase from a core group of 50 engineers yesterday, Tokyo Electric Power Co. said.
Workers plan to connect a power line to start damaged cooling systems later today and intend to spray water on a damaged reactor from a cannon used by the police for riot control, Tepco spokesman Kaoru Yoshida said. Helicopters doused 30 metric tons of water on pools used to cool spent uranium and platinum fuel rods. No change in radiation levels were reported after four bombing runs, Kyodo News said citing Tepco.
Tokyo Electric’s failure to end the threat of radiation from the Fukushima plant has prompted governments including the U.K. and Germany to advise their citizens to consider leaving Tokyo. The crisis has wiped 2.26 trillion yen ($29 billion) off Tepco’s market value since the March 11 quake, subsequent tsunami and a series of explosions and fires devastated the 40- year-old power station.
Japan’s Nuclear and Industrial Safety Agency said today there is a possibility of no water at the No. 4 reactor’s spent fuel cooling pool. The agency has detected no smoke or steam rising from the reactor, spokesman Hidehiko Nishiyama said.
Exposure of spent fuel rods to air “could result in fracturing of the fuel rod cladding and escape of dangerous radioactive fission products” such as iodine-131, cesium-137 and strontium-90, said Stephen Lincoln, an environmental chemist at the University of Adelaide.
All water in the No. 4 reactor’s spent-fuel pond has drained, U.S. Nuclear Regulatory Commission Chairman Gregory Jaczko told a congressional panel in Washington yesterday. Fuel rods stored in three reactors at the Tokyo Electric plant are exposed and releasing radiation, Yukiya Amano, head of the International Atomic Energy Agency, said in Vienna before departing for Tokyo. The plant has six reactors, three of which have been damaged by explosions following the March 11 quake.
Helicopters are also being used to determine radiation readings, water levels in the pool and damage to the reactors, Tepco spokesman Kaoru Yoshida told reporters in Tokyo today. Technicians were unable to inspect the facilities because of high levels of radiation. Water may also be sprayed from a water cannon used by the National Police for riot control.
The United Nations’ nuclear agency plans an emergency meeting on the crisis. Japan faces a “serious situation,” Amano said before departing for talks with authorities today.
“Radiation levels are extremely high, which could possibly impact the ability to take corrective measures,” Jaczko told U.S. lawmakers.
Workers at Tokyo Electric, or Tepco, are struggling to prevent a nuclear meltdown at the complex, 135 miles (220 kilometers) north of Tokyo. The No. 2 reactor’s containment vessel may have been breached, Tepco official Masahisa Otsuku said yesterday.
“We haven’t been able to get any of the latest data at any spent fuel pools,” Otsuku said. “We don’t have the latest water levels, temperatures, none of the latest information for any of the four reactors.”
Tepco said it’s building a power line to the Dai-Ichi plant’s cooling systems, which were knocked out by the quake, but was unable to say when the cable would be completed.
Series of Disasters
The failure of backup generators used to pump cooling water caused explosions in at least three of structures surrounding the station’s reactors, as well as a fire in a pond containing spent fuel rods.
Temperatures in the spent-fuel cooling pools of the shuttered No. 5 and No. 6 reactors were rising to as high as 63 degrees Celsius (145 degrees Fahrenheit) at 2 p.m. yesterday, said Tsuyoshi Makigami, head of nuclear maintenance at Tepco. Water levels at the pools at the inactive reactor Nos. 4, 5 and 6, dropped by about 2 meters, exposing the fuel rods, Amano said.
The NRC’s Jaczko said radiation at the Japanese site is fluctuating and at peak levels “would be lethal within a fairly short period of time.”
He told reporters later that the information came from NRC staff that were dispatched to Japan to help with the response and have been in contact with industry officials there. Jaczko’s assessment prompted the U.S. to recommend American citizens living within 50 miles (80 kilometers) of the plant evacuate or take shelter indoors as a precaution against possible radiation exposure. That exceeded the Japanese government’s recommendation of a 12-mile (20-kilometer) zone.
There have been more than 450 aftershocks since the magnitude-9 temblor left hundreds of thousands stranded and without power, with disruptions to food and water supplies. The Japanese government has dispatched 100,000 troops to the northeastern region.
The official death toll at 8 a.m. Tokyo time was 4,314 people, with 8,606 missing, the National Police Agency said. The tsunami and fears of a meltdown at the plant forced 451,059 people from their homes.
Eleven of Japan’s 54 reactors have been operating for 35 years or more. Two of those rank among the 10 oldest operating units in the world, according to the World Nuclear Association.