Confusion in a Crisis: Just How High Is Japan’s Radiation Risk?

It was a surreal sight: two helicopters from the Japanese Self-Defense Forces hovered above the crippled Reactor 3 at the Fukushima Daiichi nuclear plant, a huge red bucket carrying tons of seawater swaying beneath each. The helicopters made two runs above the reactor, dumping a total of seven tons of seawater into a depleted pool of water housing the spent fuel rods. Officials had acknowledged that there was a risk of radiation being released directly into the atmosphere from the increasingly exposed spent fuel rods in Reactors 3 and 4. The secondary containment buildings at each facility had been badly damaged by a massive hydrogen blast at Reactor 3 on Monday. It was not immediately clear whether the seawater was dumped on target, but by late afternoon on Thursday, the Tokyo Electric Power Co. (TEPCO), the plant’s operator, was reporting that radiation levels 300 ft. (100 m) from the plant were stable.

On the ground, meanwhile, the Self-Defense Forces moved 11 trucks bearing water cannons into position to aid in the cooling effort, while the Japanese nuclear regulator said on Thursday morning that it was working on reconnecting electric power cables to the plant, which might enable TEPCO to restart the cooling pumps. That, say nuclear experts, would mark the first bit of seriously good news since the onset of the nuclear crisis on March 11. “There’s a high probability that [reconnecting power to the plant] could change the situation for the better,” says Taira Okita, a professor at Tokyo University’s department of nuclear engineering and management.

(See pictures of the Fukushima Daiichi nuclear plant crisis.)

The ongoing struggle to snuff out the nuclear crisis occurred amid mounting confusion about key elements of risk now in play. At a hearing in Washington on Wednesday, the chairman of the U.S. Nuclear Regulatory Commission (NRC), Gregory Jaczko, called the radiation levels at one of the plant’s units “extremely high.” He added that “for a comparable situation in the United States, we would recommend evacuation for a much larger radius than is currently being provided in Japan.” And he said his information suggested that there was no water left in the pool containing the spent fuel rods in Reactor 4, an assertion which, if true, makes a significant release of radioactive gases from the burning fuel rods stored there much more likely.

On Thursday morning, the Japanese government responded to Jaczko’s assertions. Government spokesman Noriyuki Shikata said, “We have not received radiation levels that are alarming.” The Japanese nuclear regulatory agency, however, has acknowledged that it doesn’t know if there is water left in the pool. Spokesman Yoshitaka Nagayama told reporters, “Because we have been unable to go to the scene, we cannot confirm whether there is water left or not in the spent fuel pool at Reactor No. 4.” By Thursday evening, national broadcaster NHK was saying that a report had come from one of the Self-Defense Forces helicopters that had dumped seawater saying there was water present in the storage pool, but how much was unclear.

(See TIME’s exclusive pictures of the devastation in Japan.)

However, Jaczko had told the New York Times on Wednesday night that NRC representatives in Tokyo confirmed that the pool at Reactor 4 was empty. He said TEPCO and other officials in Japan had also confirmed it, though he didn’t say how they had been able to do so. Japanese government spokesman Shikata, meanwhile, disputed reports that there was any “panic” in Tokyo, adding, “We do not believe the situation in Fukushima poses any risks for people in Tokyo.”

For the moment that seems to be true. But there is no denying that the unfolding nuclear debacle has eroded some trust in Prime Minister Naoto Kan’s besieged government. Just after he was scanned for radiation in a treatment center outside Fukushima, evacuee Shigeki Watanabe said, “The government said it was safe to live here; that’s why we all do. There were never any evacuation drills, and TEPCO never told us about any risky or dangerous situations.” And people outside the evacuation zone around the plant in Fukushima are voting with their feet: some families from Fukushima have shown up in Tsuruoka, about 75 miles (121 km) to the west, residents there say.

(See how Japan became a leader in disaster preparation.)

Many Japanese were jarred when Kan said on Tuesday that there was a high risk that radiation levels around the plant would rise. He was right, but until then, there hadn’t been much talk of the risks surrounding the stricken reactor from public officials. The Prime Minister also publicly berated TEPCO executives on Tuesday for keeping him in the dark about key events at Fukushima Daiichi. “Although the explosion [at Reactor 3] was being covered on TV networks, it wasn’t reported to the Prime Minister’s office for about an hour. What’s going on here?” he asked. That unquestionably prompted some Japanese to wonder just how good the information was that they were getting. Hiroko Kano, a Tokyo housewife, was planning on delivering food and water to elderly friends who live near Sendai. She delayed the trip. “I’m just not sure I’m trusting what I’m hearing from the government,” she said.

The conflicting information about the water levels in the pool storing the spent fuel rods in Reactor 4 is emblematic of the confusion the nuclear crisis has engendered. For at least two days prior to TEPCO’s statement on Thursday that it was unclear whether there was any water left in the storage pool, international nuclear scientists had pointed to this issue as a potential danger. TEPCO must have known, experts say, that the water was boiling and being turned into steam by the red-hot fuel rods, thus increasing the exposure of those rods to the air. The same risks, the Union of Concerned Scientists pointed out, exist in Reactors 5 and 6, which are also offline and store spent fuel rods. But it was not until Thursday — after U.S. nuclear regulator Jaczko’s jarring statement about the state of Reactor 4 — that TEPCO officials publicly addressed the issue of water levels in the storage pools, and even then it did so in a way that did little to clarify the situation.

(See “After Disaster: What Defines a Country’s Resilience?”)

If millions of Japanese wondering what they need to do to get out of harm’s way are confused, there is good reason for it.

See TIME’s complete coverage of the Japan quake.

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