Pictures: A Rare Look Inside Fukushima Daiichi Nuclear Plant

After Dark Days, Some Light

Photograph from Japan Nuclear and Industrial Safety Agency via AP

Workers continued to need flashlights on Wednesday to read gauges in the control room for Units 1 and 2 reactors at Japan's Fukushima Daiichi nuclear power plant, although some power was being restored.

Only two of the six reactors at the plant, Units 5 and 6, were considered under control, but new problems emerged in the cooling system at Unit 5 on Wednesday, according to plant operator Tokyo Electric Power Company.

Workers' efforts to get the cooling pumps working have been hampered, as the crews have repeatedly been forced to evacuate due to bursts of gray smoke from the reactors. Observers say that such smoke may not necessarily be radioactive, but it demonstrates that the plant is not yet under control.

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Published March 23, 2011

Comrades in Crisis

Photograph from Japan Nuclear and Industrial Safety Agency via AP

Correction appended.

Half in darkness, workers huddle in one of Fukushima Daiichi’s control rooms.

The group of scientists and low- and middle-level managers who have stayed behind to deal with the crisis—authorities say there actually may be a hundred of them—have been hailed as national heroes in Japan.

Japan's Health Ministry more than doubled the legal limit on the amount of radiation to which each worker could be exposed, in order to maintain the workforce at the site.

Little information has been offered on the workers, except that they are rotating in shifts to limit their exposure to radiation. It is known that two workers have been missing since the earthquake and tsunami, 15 were injured in two of the reactor explosions, and more than 20 have been treated or observed for radiological contamination.*

(Related: "How Is Japan's Nuclear Disaster Different?")

Their plight recalls the "liquidators," the cleanup workers at the Chernobyl nuclear plant meltdown in Ukraine 25 years ago. Twenty-eight of those workers died from radiation exposure within weeks of the accident.

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*An earlier version of this story said it is known that five workers have died, a figure included in some early accident reports. The International Atomic Energy Agency only confirms the missing workers and injuries based on reports from Japan's Chief Cabinet Secretary. IAEA issued a report on the workers on March 17.

Published March 23, 2011

A Control Room’s Eerie Quiet

Photograph from Tokyo Electric Power Company via Kyodo/AP

The central control room of Unit 3 at Fukushima Daiichi power plant, pictured just after the lights went on Tuesday, gives little hint of the crisis inside the reactor. Unit 3’s reactor is of particular concern because its fuel is a so-called “mixed oxide” assembly. With both uranium and plutonium, it is potentially more dangerous than the uranium fuel in the other reactors in case of an explosion.

The reactors at Fukushima Daiichi, one of Japan’s oldest nuclear power plants, are of the so-called “Generation II” design of the 1970s, without “passive safety” systems that would enable the plant to continue to operate its cooling in the case of a power loss. But the vast majority of nuclear power plants now under construction around the world are also considered Generation II design; only four of the reactors now being built in China have integrated passive safety systems.

(Related: “Would a New Nuclear Plant Fare Better than Fukushima?”)

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Published March 23, 2011

Outside the Plant, More Peril

Photograph from Tokyo Electric Power Company via Kyodo/AP

In white protective suits, workers just outside the concrete containment walls work to restore electricity to the Unit 3 and 4 reactors at Fukushima Daiichi.

The restoration of power and the pumping system is crucial to get cooling to the fuel and spent fuel in the reactors, which give off decay heat and radiation for years after fission is halted.

But Japan’s concerns have turned to the spread of radiation risk outside the plant in Okumamachi.

Radioactive iodine has been detected in the water supply of Tokyo, more than 130 miles (220 kilometers) to the south. Authorities warned that infants in Tokyo and the surrounding areas should not drink tap water.

The government also said it had found radioactive material in vegetables in the Fukushima Prefecture, where the plant is located. Shipments of those vegetables were halted.

Hong Kong has banned food imports from the area, and the United States was prohibiting imports of dairy goods or produce from the region.

The emerging food and water concerns indicate that Japan’s nuclear woes may well continue long after workers stabilize Fukushima Daiichi’s radioactive fuel.

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Published March 23, 2011