Japan's nuclear power industry is among the world's most ambitious. Spurred by fears of global warming, planners envision a rapid expansion of plants, capacity and cutting-edge technologies.
But a series of radioactive leaks at the world's largest atomic plant following a killer earthquake in northwestern Japan this week has given the industry a public relations headache that will be difficult to cure.
"You cannot have nuclear power without public trust," said Jan Beranek, nuclear energy project leader for the Greenpeace environmentalist group. "And you cannot trust people who don't tell you the truth or who build nuclear plants in earthquake zones."
The sprawling, seven-reactor Kashiwazaki-Kariwa plant — the world's largest in capacity — suffered in Monday's 6.8-magnitude quake. A fire charred an electrical transformer, planks toppled into a pool of spent nuclear fuel and some 400 barrels of atomic waste tipped over.
Disclosures of radioactive leaks seeped out over several days, exacerbated by operator Tokyo Electric Power Co.'s delays in notifying the public. First came word, 12 hours after the quake, that some 315 gallons of radioactive water had sloshed out of a tank and was flushed out to sea.
In following days, TEPCO — Japan's largest power company — released a list of 50 malfunctions, damages and mistakes, announced that radioactive materials had spewed from an exhaust vent, and had to acknowledge the water leak contained 50 percent more radioactivity than initially reported. The list was later updated to 63 cases.
The company was further embarrassed on Thursday when yet another leak was discovered from an exhaust vent, indicating leaks continued as late as Wednesday night, nearly three days after the quake.
TEPCO, regulators and even environmentalists agreed the amounts of radioactivity involved were minuscule and posed no threat.
But the most damaging result from the troubles was the realization that the world's largest nuclear power plant was not structurally equipped to withstand such a powerful earthquake — this despite Japan's long history as one of the most seismically active places on Earth.
Until last year, Japan had required plants to be built to withstand a 6.5-magnitude quake. In September, the government began implementing tougher guidelines, though they have not set a fresh magnitude level.
Regulators acknowledge they need to take a fresh look at the rules.
"Earthquake safety at nuclear facilities is an issue of utmost concern to the public, and it's imperative that we ensure safety as soon as possible," said Atsuyuki Suzuki, chairman of the Nuclear Safety Commission.
For some scientists, however, no guidelines would be enough to protect a plant.
Katsuhiko Ishibashi, earthquake specialist at Kobe University's Research Center for Urban Safety and Security, said one problem is that scientists are unable to pinpoint fault lines with any accuracy.
"This situation clearly showed the insufficiency of the old guidelines for examining the seismic design of nuclear power plants," he said, arguing no plant could survive a direct hit from an earthquake.
The troubles facing Japan's nuclear industry come just as it is getting a boost because of concern over climate change. Atomic power figured high in the government's proposal to cut world greenhouse gas emissions in half by 2050.
Japan has 55 reactors producing about 30 percent of its electricity, with plans to build another 11 reactors by 2017, eventually boosting nuclear power's share of electricity production to 40 percent.
Down the road, the government is pushing for development of next generation light water reactors around 2030, and so-called "fast-breeder" reactors that produce plutonium that can be reused as fuel, fulfilling a Japanese dream of energy self-sufficiency.
Japan, however, already faces difficulties in finding communities willing to host reactors, mostly because of a long list of past accidents and cover-ups of malfunctions — including some at TEPCO.
The problems at Kashiwazaki could make that expansion even more difficult. While many Japanese understand the need for energy to power the world's second-largest economy, they are hesitant to trust operators.
"It is impossible to guarantee 100 percent safety," conceded Yumi Shimoda, a 40-year-old marketing consultant in Tokyo. "But what scares me is the fact that they tried to cover up the truth in order to claim safety."