Fuel rods in three reactors at the Fukushima Dai-ichi nuclear plant in Japan appear to be melting, again raising the likelihood of at least a partial meltdown.
All three had lost their cooling systems in the devastating 9.0-magnitude earthquake and massive 23-foot tsunami that struck Japan last Friday.
Millions in Crisis, Death Toll Climbing
Millions of people were facing a fourth night Monday still without electricity, water, food or heat in near-freezing temperatures. The death toll continued to climb, with estimates exceeding 10,000 in the Miyagi prefecture alone, according to local police.
Two Israelis are still unaccounted for – one tourist, and one person who has lived in Japan for years. Just after the earthquake struck, the number of Israelis unaccounted for was as high as 28.
Aftershocks continue to rock the country, with the strongest so far measuring 7.1 on the Richter scale. An additional 180,000 people followed an initial evacuation of 350,000 from a 20-kilometer radius of the Fukushima nuclear complex after a partial meltdown of one of the reactors on Saturday.
Meltdown Likely, Fuel Rods Exposed
A total of four nuclear plants were damaged in the twin disasters. But it is the Fukushima Dai-ichi complex, with its three operational reactors located close to the Pacific coast, that was badly damaged in the tsunami.
“Although we cannot directly check it, it's highly likely [a partial meltdown is] happening,” Chief Cabinet Secretary Yukio Edano told reporters late Monday.
According to Nuclear and Industrial Agency official Ryohei Shiomi, uranium fuel rods were completely exposed – twice -- in one of the reactors when water levels dropped suddenly. The second drop came following a hydrogen explosion that blew the roof off a building in the plant complex Monday morning.
Eleven workers were injured in the blast, ABC News reported.
The first time, the drop came due to an explosion that followed the tsunami. Water levels were restored by flooding the reactor with sea water. But the second time the rods remained exposed, and by late Monday night there appeared to be an increased risk for an eventual meltdown.
“Units 1 and 3 are at least somewhat stabilized for the time being. Unit 2 now requires all our effort and attention,” he said.
It was in Unit 3 that two separate explosions occurred – the most recent Monday morning – after scientists flooded the overheated reactor cores with sea water in a desperate bid to cool them down to prevent a meltdown.
Flooding the reactor with sea water was bound to cause a buildup of pressure in the reactor containment vessels, and that might have led to an explosion, according to scientists. But there appeared to be no other choice.
Ultimately, the hydrogen in the steam that was released mixed with the oxygen in the air, thus igniting the two explosions.
Ironically, the blast also reduced the pressure that had been building up inside the reactor in Unit 3. In addition, the containment shell, a thick wall of concrete around the reactor, remained intact.
US Soldiers Cite Radiation Exposure
Officials imposed a quarantine and anyone within a 12-mile radius was ordered to remain indoors even though Cabinet Secretary Noriyuki Shkata told journalists at a news conference, “We have no evidence of harmful radiation exposure.”
U.S. officials were not so sure, however.
Military personnel involved in helicopter relief missions from the USS Ronald Reagan, an aircraft carrier waiting some 100 miles offshore, returned to ship showing signs of radiation exposure.
The 17 soldiers were found to have been exposed to a level equal to one month's normal exposure to natural background radiation. They were decontaminated by scrubbing with soap and water, while the carrier and other 7th Fleet vessels took precautions by moving to another area.
Fears of Radiation Sickness
Many Japanese and others living in the country are afraid of developing radiation sickness, despite reassurances by officials that the risk is low.
At least three Fukushima workers have already suffered acute radiation sickness, according to a report by CTV.
The Japanese government has ordered the distribution of iodine pills to everyone in the area of the disabled nuclear reactors. The iodine is intended to prevent thyroid cancer by flooding the gland, thereby inhibiting its absorption of radioactive iodine from the atmosphere.
There are conflicting reports on how much radiation has actually leaked from the reactors, and how much might yet escape. However, it is clear that any significant exposure to radiation increases one's risk of developing radiation-related health problems.