On many Friday evenings, 38-year-old Tomo Iwabuchi and six friends can be found on a street corner in Fukushima City, banging drums, chanting and singing. "Zero nukes!" Iwabuchi yells into a microphone as a few pedestrians stride by.
"The Fukushima disaster — it's not over yet," chimes in Kazushi Machida, another demonstrator, referring to the nuclear power plant about 50 miles southeast that experienced a triple meltdown after Japan's massive March 2011 earthquake and tsunami. "The cleanup is still going on, and yet the government wants to restart other nuclear plants!"
Nearly four years after Japan shut down all of its atomic energy plants in the wake of the disaster, the country is inching toward a momentous decision on whether to bring some of them back on line, perhaps within the next year.
Such a move would have been unthinkable immediately after the disaster, which struck terror in the hearts of many Japanese and caused concern around the world. Though nuclear power provided 30% of Japan's energy before the accident, the government of then-Prime Minister Naoto Kan called on the country to give up its reliance on the technology, and opinion surveys showed that up to three-quarters of the public supported such a move.
An October poll by Kyodo News found 60% of respondents still opposed to restarts, but the conversation has started to shift because of a variety of factors, including the introduction of more robust regulation and the creation of new oversight bodies, and the installation in late 2012 of a government led by Shinzo Abe, who introduced a new energy policy last year backing nuclear power.
Japan is the only nation to have nuclear bombs dropped on it, and emotions about radiation here are deep and complex. But mounting concern about higher electricity costs, greater dependence on imported fossil fuels and rising carbon emissions are also figuring into Japan's calculus. After an initial summer of brownouts, the country replaced lost nuclear power by revving up plants fueled by natural gas and coal.
Progress at the Fukushima Daiichi nuclear power plant may be softening some opposition as well. The four damaged reactors have been in "cold shutdown" mode for more than three years, and about 7,000 people are on site doing decommissioning work. They reached a milestone in December by completing the removal of all spent and fresh fuel from the spent-fuel pool in Unit 4.
But decommissioning activities are expected to take at least two decades, and inspectors from the International Atomic Energy Agency said last month that the situation at Fukushima remains "very complex." Worker safety is still a critical concern, and high radiation means technicians are still unable to enter some structures and must rely on robots to inspect some damaged reactors.
One of the most pressing issues highlighted by the IAEA is what to do with nearly 158 million gallons — or 600,000 cubic meters — of contaminated water being stored in an ever-growing tank farm on the site. With engineers still unable to stop groundwater from flowing into the damaged reactors, 300 cubic meters of water is added to the inventory each day. In January, a worker inspecting a tank fell and died.
This month, Tokyo Electric Power Co., known as Tepco, said 750 tons of water contaminated with strontium-90 may have seeped from the tank area into the ground. Small amounts of contaminated water have also been leaking into the Pacific Ocean, Tepco acknowledged last month, though it called the amounts inconsequential.
Tests in January found that only 0.3% of all seafood samples caught by the Fisheries Agency of Japan exceeded legal limits for radiation. But with fresh leaks occurring, concern about the effect on marine life has not abated, and coastal fishing off Fukushima prefecture remains suspended, as it has been since the accident.
Whether the government can find a technically feasible — and politically palatable — solution to the water issue is crucial both for reducing hazards for workers at the Fukushima site and building confidence at home and abroad that Japan is turning the corner on the disaster and is ready to restart other nuclear plants.
"This issue of water, it involves everyone — from fishermen, to the Ministry of Agriculture, Forestry and Fisheries, to civil engineers at the Ministry of Land, Infrastructure, Transport and Tourism," said Tatsuya Shinkawa, director of the Cabinet Office's Contaminated Water and Decommissioning Issues Team. "Other countries are asking questions too, so the Ministry of Foreign Affairs is involved as well."
Edwin Lyman, coauthor of "Fukushima: The Story of a Nuclear Disaster" and a nuclear expert at the Union of Concerned Scientists, said the post-accident management of water "has been a lot more complex than anyone imagined."
"If they are going to be restarting plants in Japan, they need to think harder about it," he said.
Over the last four years, Tepco and the government have tried, with limited success, to halt the inflow of groundwater, and now are even trying to freeze the ground around the reactors. They've installed systems to treat the contaminated water, removing a variety of radioactive contaminants, including cesium and strontium. The company said March 16 that 90% of stored water would be processed through those systems by May.
But those systems can't remove radioactive tritium, which is closely related to hydrogen. Water is a compound of hydrogen and oxygen, and tritium bonds like hydrogen with oxygen to produce "tritiated water." Tritiated water is odorless and colorless, and the tritium is hard to isolate.
Tritium is not considered as dangerous as cesium or strontium, because it emits very low-energy radiation, has a short half-life and if ingested leaves the body relatively quickly. Tritium is one of the least dangerous radionuclides, according to the U.S. Environmental Protection Agency. The IAEA has even called on Japan to consider releasing its stores of tritiated water, presumably into the ocean.
"But any release of radioactivity is very emotional," said Lake Barrett, director of the U.S. Nuclear Regulatory Commission's Three Mile Island cleanup site office from 1980 to 1984, who is now a special advisor to Tepco's president.
"Fishermen will tell you if this is released, no one will buy our fish. South Korea and China may protest and act holier-than-thou, even though they have reactors that release tritium on a regular basis," Barrett said. "My opinion is it should be released, but Japan is looking at all the available technology to deal with this."
A tritium task force has been studying the issue.
"We've got about one year to figure this out," said Teruaki Kobayashi, general manager in Tepco's nuclear power and plant siting division. "As of now, inside the company, we have no certain direction about what to do, but after we hear the suggestions from them, we will decide our course of action."
Central to the deliberations is an Orange County company, Kurion, which received a multimillion-dollar contract from Tepco last year to try to devise a solution for the tritiated water.
Gaetan Bonhomme, chief technical officer for Kurion, said the company has a system that can separate tritium from water but needs to show that it can scale it up to deal with the massive amounts of liquid at Fukushima. Kurion's system, he believes, could remove the tritium from 800,000 cubic meters of water so that only about a cubic meter of the radioactive material remained.
By his estimates, the process would take five to eight years, and cost about $1 billion to set up, plus several hundred million dollars a year to operate.
"Some people will say that's expensive, but compared to what? I'd be very interested to talk to someone who says you should release this water, and discuss the costs of that," he said. "How would you do it? What would be the impact? And how would you compensate people who might be affected?"
(Decommissioning is already expected to cost $8.5 billion, Kobayashi said, but Tepco believes it will need an additional $8.7 billion over the next 10 years for "unanticipated" expenses.)
In Japan, cost considerations may take a back seat to other concerns, such as convincing the public that Tepco is adhering to national guidelines on releases of radioactive material.
Japan, Bonhomme said, has regulations both on the concentration of tritiated water that can be released and annual total volume limits. Tepco could find ways to dilute the tritiated water, he said, but the amount of tritium it has on hand now is 40 times the annual release limit.
Barrett said that the rules should be changed and that technology to remove tritium is "not practical." But he noted that "the Japanese are much less sensitive to cost than we Americans." The Three Mile Island cleanup cost about $2.3 billion in today's dollars, he said, but the Fukushima cleanup "is much more expensive than I would have thought."
No matter what Tepco or the government spends on remediation and decommissioning at Fukushima, it's unlikely to convince people like Hiromitsu Ito that restarting nuclear plants is a good idea.
The fisherman from the northern town of Ogatsu near Sendai says he's long been against nuclear power and he's outraged by the fact that no one has been criminally prosecuted for the Fukushima meltdowns.
"I think the Tepco people are criminals but they have never been dealt with," he said. "People in the nuclear industry have learned from this that they will never be punished."
Eiju Hangai is another skeptic. A former Tepco board member, he retired from his position a year before the Fukushima disaster and now has thrown himself into promoting solar power.
In the city of Minamisoma, just north of the mandatory evacuation zone around the nuclear plant, he has built a small solar park and conducts workshops for schoolchildren, teaching them about green energy.