OCTOBER 31, 2011

Radiation Cleanup Confounds Japan

KORIYAMA, Japan—Nearly eight months after the Fukushima Daiichi nuclear accident scattered radioactive material over surrounding communities, Japan still is struggling to figure out how to clean up the mess, exacerbating fears about health risks and fanning mistrust of the government.

Thirty miles away from Japan's crippled Fukushima Daiichi nuclear plant, the residents of Koriyama are on a mission to help rid their town of harmful radioactive materials. WSJ contributor Sebastian Stein reports.

Government guidelines provide scant detail about the $14-billion-plus effort. A new cleanup law doesn't take effect until January. Cities across Fukushima prefecture are scraping contaminated topsoil off school grounds and parks, but Tokyo hasn't yet decided where to store the tainted material. Frustrated residents of some towns have planted sunflowers in a fruitless effort to suck radioactive cesium out of the farmland.

Here in this city of 332,500 nearly 40 miles from the crippled reactors, local volunteers regularly hose down sidewalks where radiation readings are high, even though that could spread contamination into sewage systems. "Everybody is groping in the dark," says Hiroto Nishimaki, a 48-year-old executive of a gardening company near here. Japan Real Time

Nuclear Cleanup Faces Nimby Challenge

After a client asked to have contaminated grass removed, Mr. Nishimaki called the local labor-inspection office to check if he needed a license to handle radioactive material. The labor office referred him to the education ministry, which passed him on to the environment ministry, which passed him back to the education ministry, he says. Frustrated, Mr. Nishimaki went to a local assemblyman and was told no license was required.

Japan's struggle to come up with a cleanup plan has exposed a critical shortcoming: weak central decision making. Since the March 11 earthquake and tsunami, a lack of clear leadership on the issue, combined with bureaucratic divisions, has slowed the government's response and diluted accountability.

A volunteer hoses down the sidewalk near Koriyama Daiichi Junior High School earlier in October in an effort to reduce the radiation level.

In the crucial early days after the tsunami knocked out power to cooling systems at the Fukushima Daiichi nuclear plant, the government and plant operator Tokyo Electric Power Co. argued over who was in charge of containing the escalating disaster. Officials delayed the evacuation of residents in hot spots, despite information that radiation levels were high. They didn't distribute iodine pills to protect against thyroid cancer, despite calls from some experts to do so. They insisted that meat and vegetables produced around the nuclear facilities were safe, although they didn't adequately test for radiation.

How Japan fares in cleaning up the radioactive contamination will determine, in part, the extent of any long-term damage. The longer Japan waits to take action, the greater the chances that radioactive materials will spread through wind or rain and get into water and food supplies. Radioactive cesium, which experts say can stick around for as long as 300 years, has a tendency to bind to earth and be carried by silt in water. Earlier in October, Japan detected the highest radiation levels yet outside of Fukushima prefecture in a community 125 miles from the plant, raising new fears about the extent of contamination.

; Uncertainty about the health effects of low-level contamination has complicated the cleanup challenge. Science doesn't provide clear answers about the point at which contamination becomes an unequivocal health risk. High radiation levels, such as from an atomic bomb, are clearly dangerous, even deadly. But the effects of lower levels, which play out over many years, are murkier, fueling debate over how much of Japan needs to be cleaned up.

Some experts say some ad hoc cleanup efforts risk spreading radiation further. Schools across Fukushima are temporarily storing contaminated soil in holes dug within the school compounds and lined with plastic sheets. But plastic isn't a long-lasting seal against radioactive substances leaking, says Kimberlee Kearfott, a University of Michigan nuclear-engineering professor who has served on U.S. government panels for nuclear cleanups. If radioactive materials get into the ground water and are concentrated there, she says, that could be worse than soil contamination because it could spread rapidly.

"This type of shallow-pit burial has not been used in the U.S. since the 1960s," she says. "This is definitely not a good idea."

Officials at Japan's environment ministry, which will officially take charge of the cleanup in January, say the responsibilities should become clearer, but concede the task is daunting. "We don't have experience in this field," Vice Minister Hideki Minamikawa said in an interview. "We're talking about such a vast area," especially when including contaminated sludge piling up in places beyond Fukushima prefecture. "Currently, there are no clear signs yet on what needs to be done to make decontamination a success," he said.

Other nuclear cleanup efforts have taken years. In Chernobyl, 25 years after the nuclear accident, radiation is still detected in the surrounding forests, experts say. The U.S. government has spent more than $34 billion over two decades at a nuclear-cleanup site in Hanford, Wash., a 586-square-mile site contaminated over four decades. Underground waste-storage containers there, thought to be impermeable, leaked. The cleanup is expected to take another 50 years and cost an additional $115 billion, according to the Department of Energy.

Human exposure to radiation is measured in units called sieverts. World-wide, the average person is exposed to about 2.4 millisieverts a year from the environment, cosmic rays and food, not including X-rays and some other man-made sources. In Japan, prior to the disaster, the average exposure was 1.5 millisieverts, according to the Japanese government.

Japan's ceiling for what it calls safe—20 millisieverts per year—is one-fifth the level at which many scientists say clear evidence of health risks emerges. But 20 millisieverts per year is at the top of a range that the International Commission on Radiological Protection, an independent international body, says shouldn't be exceeded over the long-term after an accident. In the long run, Japan is aiming to reduce radiation levels to one millisievert per year or less—a goal that may be hard to achieve in some places, experts say.

In September, Japan's environment ministry suggested the government would fund a thorough decontamination of areas with radiation exposure of five millisieverts per year or more. After local officials complained, the government expanded the cleanup area to a zone with exposure of one millisievert or more—an estimated 4,500 square miles of land.

Japanese government officials say the nation didn't have a plan for a widespread nuclear accident, and in the first months after the disaster, no ministry was fully in charge of the cleanup. The Nuclear and Industrial Safety Agency, which was most knowledgeable about nuclear issues, dealt only with contamination at the nuclear plant. The environment ministry only monitored radioactive levels in remote islands, in part to detect weapons tests overseas.

Responsibilities were narrowly divided among various ministries: the education and science ministry monitored radiation levels and advised schools; the agriculture ministry monitored farm soil; the land ministry was in charge of contaminated sludge in the sewer system. The nuclear-emergency response headquarters at the prime minister's office, made up of representatives from various ministries, was supposed to coordinate all nuclear-related measures. But government officials acknowledge they didn't make some big decisions, such as crafting a decontamination plan and deciding where to permanently store radioactive waste.

In August, five months after the accident, parliament passed a law putting the environment ministry in charge of the cleanup. Officials haven't yet determined how best to clean the most contaminated areas before the law takes effect Jan. 1.

One challenge: Keeping track of all the different plans popping up. The national government intends to devise a cleanup plan soon for the most highly contaminated areas, which are currently evacuated, where exposure exceeds 20 millisieverts per year. For cities with lower-level contamination, the new law directs local governments to come up with their own plans based on government guidelines, which Tokyo will fund.

Local officials In Koriyama say that, in April, one school detected radiation that would amount to more than 20 millisieverts over the course of a year. At that time, the government's guidance was to restrict outdoor activity for schools with high radiation levels, but there were no guidelines on how to reduce the contamination levels.

Koriyama officials contacted nuclear experts and were told that removing a layer of topsoil from school grounds could reduce radiation levels, because cesium tends to collect in the top layers. A half-hour experiment confirmed that advice, so in late April, officials started a soil-scraping drive at schools.

Fumiyasu Hirashita, chief of the education-ministry unit handling inquiries about school decontamination, says the ministry didn't stop Koriyama's effort but didn't actively support it at first. Then it conducted its own experiment and found that soil-scraping worked. In May, it said Japan would pay for the effort. More than 300 schools in Fukushima prefecture have used the technique.

Of the four areas in Koriyama tracked by the education ministry, the highest radiation level currently detected is 9.8 millisieverts per year.

But the soil-scraping created another dilemma: what to do with the contaminated dirt. No ministry was in charge of that issue. The education ministry suggested one option—bury it.

The government recently directed each municipality to find a temporary storage space for the waste while it secures an "interim storage facility" and debates the sensitive issue of where to store the waste permanently.

Koriyama initially planned to bury the soil in a city landfill, but local residents objected. The city asked each school to store the soil on their own property while awaiting direction from Tokyo.

Koriyama Daiichi Junior High School, one of the first schools to remove topsoil, piled the dirt in the corner of the school grounds. Eventually, it dug a hole underneath the faculty parking lot and lined it with plastic, fresh soil and pebbles.

Nuclear experts say the trick to successful decontamination is to swiftly collect and isolate radioactive material—not to move it from one temporary storage space to another. Schools all over Fukushima, for now, either have buried contaminated soil or piled it in one corner of their properties. It isn't clear how long the soil will stay there. If cesium breaches the layer of plastic, bugs, weeds and mice could draw it to the surface again, creating new radiation hot spots, some say.

Jim Tarpinian, who worked on the Hanford, Wash., cleanup and now is chief safety officer at a U.S. Department of Energy lab in Menlo Park, Calif., says ad hoc cleanup efforts are risky. "It has to be carefully planned so you don't make the situation worse," he says.

Cleaning up Fukushima's sprawling farmlands could create an even bigger storage problem. Farms haven't planted rice in soil where emitted radiation has been measured in excess of 5,000 becquerels per kilogram. The agriculture ministry now says removing that contaminated topsoil may be effective. If just four centimeters of topsoil is scraped off the contaminated farmland, the ministry says, it would create 3.3 million tons of waste.

Some Koriyama residents feel more action is needed. Mitsutoshi Hori, a 62-year-old owner of a housing-materials company, says his daughter and her two children left in May for fear of health risks.

Mr. Hori has organized 70 volunteers to clean the streets around the schools every Sunday. On a recent weekend, Mr. Hori, decked out in raingear and a surgical mask, aimed a high-pressure hose at small cracks in a muddy sidewalk, where cesium tends to collect. Another volunteer measured the radiation level: 1.5 microsieverts an hour. The goal is to get it down to 0.2 microsieverts.

Mr. Hori acknowledged that the cesium he was washing off sidewalks may end up in the city's sewage system. But he said the volunteers were following the city's decontamination manual—and helping to make the area safe for children walking to school. "I want the people who have left to come back, and to make Koriyama's economy vibrant again," he said. —Peter Landers contributed to this article.

Write to Yumiko Ono at yumiko.ono@wsj.com

Your comments and suggestions are appreciated.



Don't cite this page:
It has links to article all separately copyrighted.
Each article will be used only by those few (if any)
students in any year needing the material.
[Saturday, 20-Oct-2018 21:25:06 EDT]
Edited by: wilkins@mps.ohio-state.edu on Monday, 31-Oct-2011 17:41:50 EDT