TOKYO—For months now, it has been hard to escape the continuing deluge of bad news from the devastated Fukushima nuclear power plant.
Even after the company that operates the plant admitted this summer that tons of contaminated groundwater was leaking into the Pacific Ocean every day, new accidents have added to the uncontrolled releases of radioactive materials. This week, newly tainted rainwater overflowed dikes. Two weeks before that, workers mistakenly disconnected a pipe, dumping 10 more tons of contaminated water onto the ground and dousing themselves in the process.
Those accidents have raised questions about whether the continuing leaks are putting the environment, and by extension the Japanese people, in new danger more than two and a half years after the original disaster—and long after many had hoped natural radioactive decay would have allowed healing to begin.
Interviews with scientists in recent weeks suggest that they are struggling to determine which effects—including newly discovered hot spots on a wide swath of the ocean floor near Fukushima—are from recent leaks and which are leftovers from the original disaster. But evidence collected by them and the plant’s operator, the Tokyo Electric Power Company, or Tepco, shows worrisome trends.
The latest releases appear to be carrying much more contaminated water than before into the Pacific. And that flow may not slow until at least 2015, when an ice wall around the damaged reactors is supposed to be completed. Beyond that, although many Japanese believed that the plant had stopped spewing radioactive materials long ago, they have continued to seep into the air.
"This has become a slowly unfolding environmental misery," said Atsunao Marui, a geochemist at the Geological Survey of Japan who has studied contaminated groundwater flowing from the plant. "If we don’t put a stop to the releases, we risk creating a new man-made disaster."
Even the most alarmed of the scientists who were interviewed did not extend their worries about the new releases to human health. With more than 80,000 residents near the plant evacuated almost immediately after the disaster, and fishing in nearby waters still severely restricted, they say there is little or no direct danger to humans from the latest releases. But, they say, that does not rule out other impacts on the environment.
And while the air and water releases are a small fraction of what they were in the early days of the disaster, they are still significantly larger than what would normally be permitted of a functioning plant.
Besides the discovery of widespread radioactive hot spots, the government’s fisheries agency said that more than 1 in 10 of some species of bottom-feeding fish caught off Fukushima are still contaminated by amounts of radioactive cesium above the government’s safety level.
Less attention has been paid to the continued airborne releases of cesium from the site’s crippled reactors, whose layers of protection were damaged or destroyed. The plant still emits 10 million becquerels per hour into the atmosphere, according to Tepco.
Tepco has tried to stop these continuing releases by taking steps like erecting a cover over one damaged reactor, but it acknowledges that radioactive materials still escape through tiny gaps in the cover, or through damaged ventilation systems and cracks in the reactor buildings. So long as such air and water releases continue, experts warn, there will be no end to Fukushima’s slowly unfolding environmental damage.
"These aren’t levels that are going to directly affect human health," Masashi Kusakabe, a researcher at an institute that has monitored cesium in the ocean for the government, said, referring to releases into the Pacific.
"But that doesn’t mean that therefore these releases are good or acceptable," he said. "There is no precedent for what is happening, so we are on untrodden ground."
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