Story highlights 350 people from the Miyakoji district of Tamura city will be allowed to head home

20-kilometer (12-mile) exclusion zone declared around crippled nuclear plant since 2011

Devastating earthquake and tsunami knocked out the Fukushima nuclear plant

Many residents remain concerned about radiation levels despite decontamination efforts

Japan's government is to allow some residents around the crippled Fukushima nuclear plant to return to their homes to live for the first time since the March, 2011 disaster.

Tens of thousands of people were evacuated and a 20-kilometer (12-mile) exclusion zone declared around the plant after a devastating earthquake and tsunami triggered a reactor meltdown -- the world's worst nuclear disaster since Chernobyl in 1986 -- causing high levels of radioactive contamination.

Once bustling communities in this pocket of eastern Japan were turned into ghost towns.

But on April 1, some 350 people from the Miyakoji district of Tamura city will be allowed to head back to their homes permanently, according to the country's Reconstruction Agency. Some 31,000 people could eventually return home, it added.

The government says about 138,000 Fukushima residents are still living in temporary accommodation.

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At a meeting Sunday, Miyakoji residents were told that radiation contamination levels had lowered sufficiently for their return to the area -- though some voiced concern over existing radiation levels despite decontamination efforts around some communities.

Areas are declared suitable for habitation if residents are exposed to a maximum of 20 millisieverts of radiation per year. Officials have said they would like to get radiation exposure down to one millisievert a year.

Fukushima leaks

The containment effort at the wrecked Fukushima-Daichi plant has been beset by problems, with regular reports of leaks of contaminated material. Last week, an estimated 100 metric tons of highly contaminated water flowed over a barrier around a containment tank and is being absorbed into the ground, plant operators, Tokyo Electric Power Company (TEPCO), said in a statement -- though it denied there was any leakage into the nearby Pacific Ocean.

Prime Minister Shinzo Abe's government vowed to step in to deal with the toxic water crisis at the plant that caused concern in Japan and abroad about the scale of the problem faced by TEPCO.

The leak reported Thursday is one of the largest since TEPCO reported last summer that about 300 tons of radioactive water had leaked from a tank.