- Associated Press - Thursday, March 8, 2012

FUKUSHIMA, JAPAN Workers in rubber boots chip at the frozen ground, scraping until they’ve removed the top 2 inches of radioactive soil from the yard of a single home.

Total amount of waste gathered: roughly 60 tons.

One down, tens of thousands to go.

And since wind and rain spread radiation easily, even this yard may need to be dug up again.

The work is part of a monumental task: a costly and uncertain effort by Japan to try to make radiation-contaminated communities inhabitable again.

Some contractors are experimenting with chemicals; others stick with shovels and high-pressure water. One government expert says it’s mostly trial and error.

The radiation leak has slowed considerably at the Fukushima Dai-ichi nuclear plant, nearly one year after the March 11 earthquake and tsunami sent three of its reactors into meltdown.

Work continues toward a permanent shutdown, but the Japanese government declared the plant stable in December, setting the stage for the next phase: decontaminating the area so at least some of the 100,000 evacuated residents can return.

Specialists leading the government-funded project cannot guarantee success. They say there’s no prior model for what they’re trying to do.

Even if they succeed, they’re creating another problem they don’t yet know how to solve: where to dump all the radioactive soil and debris they haul away.

• Uncertain outcome

The government has budgeted $14 billion through March 2014 for the cleanup, which could take decades.

The uncertainty plays out at many levels. One of the workers at the house with the frozen ground said they weren’t sure how to measure 2 inches from the uneven ground or what to do with the snow on top of it.

“We often encounter situations that are not in the manual and wonder if we are doing the right thing,” Takahiro Watanabe said as they wrapped up on a chilly February day. “Just to be safe, we packed the snow into the bags.”

The 60 tons of radioactive waste sat in 60 waterproof bags, waiting to be carted away from the house in Fukushima city’s Onami district.

Some 40 miles from the nuclear plant, the neighborhood is a “hot spot” - an area with high radiation readings that is outside the 12-mile ring that has remained closed since the early days of the crisis.

Residents of hot spots were encouraged, but not ordered, to leave, and some, including the residents of the house that was being decontaminated, did not moved out.

In the fading late afternoon light, Mr. Watanabe took a dosimeter in his bare hand and placed it on the ground, now covered with a fresh layer of replacement soil. It read 0.24 microsieverts per hour - close to the target level of 0.2 and about one-fifth of what it had been before.

“Looks like it has come down a bit,” he said.

But for how long? With so much radiation in the area, workers probably will have to return to redo this neighborhood.

And areas where children gather, such as parks, schools and playgrounds, will be held to an even stricter standard than homes and offices.

“You have to keep cleaning up,” said Toshiaki Kusano, Fukushima city’s top crisis management official.

The city has a five-year decontamination plan, which he said could be extended.

For evacuees, a major step forward may come in the next few weeks, when officials hope to redefine the evacuation zone, possibly opening up some areas, based on radiation data.

• Decontaminating earth

Radiation accumulates in soil, plants and exterior walls of buildings. Workers start cleaning a property by washing or chopping off tree branches and raking up fallen leaves.

Then they clean out gutters and hose down the roof with high-pressure water. Next come the walls and windows.

Finally, they replace the topsoil with fresh earth.

Historically, the only parallel situation is Chernobyl, where the contaminated area - once home to 110,000 people - remains off-limits nearly 26 years after the nuclear power plant exploded.

“They abandoned the land,” Environment Minister Goshi Hosono told a meeting of local officials and residents last month. “We won’t give up. The land belongs to each village, to each resident.

“As long as there are people who want to return home, we’ll do everything we can to help.”

In an interview with a group of reporters, though, he conceded that such a massive cleanup is “untested.”

Experts say it may be possible to clean up less-contaminated areas, but nothing is promising in the most contaminated places, where any improvement is quickly wiped out by radiation falling from trees, mountains and other untreated areas.

Most of the cleaning is taking place in less-contaminated areas, but the government also launched pilot projects in 12 districts around the plant, most of them highly contaminated, in December.

Major construction companies and others won government contracts to experiment with methods to remove and compact the overwhelming volume of waste. Those found effective will be chosen for further cleanup starting in April.

The dozens of methods range from the relatively basic - soil removal and washing and scrubbing surfaces - to the more experimental, such as using chemicals to remove radioactive cesium from farmland, and dry ice to get it out of roads and other hard surfaces.