"The situation around Iwaki is unsettled and unruly," said Ryosuke Takaki, a professor of sociology at Iwaki Meisei University, who has studied the town's developing divide. "There are many people who have evacuated to Iwaki, and there are all kinds of incidents caused by friction."
Hosts weary, guests frightened
Residents across Fukushima prefecture hailed the first wave of workers who arrived to contain the nuclear disaster in 2011 as heroes. Cities like Iwaki also welcomed evacuees from towns closer to the meltdowns and explosions. At the time, Japan's stoicism and sense of community were praised around the world for helping those who survived an earthquake and tsunami that killed nearly 19,000 and triggered explosions at the nuclear plant.
But that solidarity and sense of shared purpose has frayed, according to dozens of interviews. Many Iwaki residents say they have grown weary of hosting evacuees in temporary housing.
And the newcomers themselves are frightened, says Hideo Hasegawa, who heads a non-profit group looking after evacuees at the largest temporary housing complex in Iwaki.
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"When they move in to an apartment, they don't talk to neighbors and hide," said Hasegawa, who works from a small office located between rows of grey, prefabricated shacks housing the evacuees. "You hear this hate talk everywhere you go: restaurants, shops, bars. It's relentless."
The 2011 nuclear crisis forced more than 160,000 people in Fukushima prefecture to evacuate and leave their homes. Half of them are still not allowed to return to the most badly contaminated townships within 20 kms (12.4 miles) of the destroyed plant known as the exclusion zone.
Since April, the government has allowed some residents to return to parts of the evacuation zone. But the area remains sparsely populated and riddled with hot spots where radiation is as much as four times the government's target for public safety. Work crews in white decontamination suits have poured radiation-tainted topsoil and debris into black-plastic bags piled at improvised storage sites on roadsides and public parks awaiting a shift to a more permanent nuclear waste dump.
By contrast, Iwaki has prospered. On a recent Saturday, parking lots near downtown were packed - along with restaurants near Taira, the city's downtown. Chuo-dai Kashima, a newly developed area in Iwaki where many of the temporary housing units have been built, saw an almost 12 percent rise in land prices in the past year, according to government data. That was among the highest increases across Japan and behind only Ishinomaki, Miyagi, a coastal city that was destroyed by the 2011 tsunami and has only just begun to rebuild.
The new millionaires
At the heart of the tensions is an unresolved debate about how much people across Fukushima should be compensated for the suffering, dislocation and uncertainty that followed the nuclear accident.
Some Iwaki residents grumble they are being forced to shoulder the burden of hosting evacuees who receive far more compensation from the government and do not have to pay rent on their government-provided prefab temporary homes.
In January 2013, vandals threw paint and broke windows on cars parked in evacuee housing at multiple locations. Less than a month earlier, someone had painted graffiti reading, "Evacuees Go Home" at the entrance to a city office.
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Tokyo Electric Power, the operator of the Fukushima plant, has paid almost $41 billion in compensation as a result of the nuclear accident. Payments vary depending on the amount of radiation recorded in a particular area, a system that evacuees have complained appears arbitrary. A family of four in one part of an evacuated town might receive $1 million, while a similar family in a less contaminated part of the same evacuated town would get just over half of that amount, according to data from Japan's trade ministry.
The radioactive plume that erupted after a partial meltdown at the Fukushima plant traveled northwest, missing Iwaki. Most of Iwaki's residents evacuated for a while, but most then returned. Their compensation was also limited: the majority received about 120,000 yen ($1,200) each.
Many established residents in Iwaki complain government payouts to the newcomers have been frittered away on luxury cars and villas, locally dubbed "disaster relief mansions."
"The food the evacuees eat and the clothes they wear are different," said Hiroshi Watahiki, 56, a chiropractor in Iwaki. "They can afford it from their compensation funds. They have time and money to go gambling since they're not working."
A poll in January by Takaki showed residents had conflicting feelings about the evacuees. More than half of those surveyed expressed sympathy for them, but 67 percent also said they "feel envious of their compensation."
The tensions are unlikely to be resolved any time soon.
The government is planning to build 3,700 permanent apartments to replace the temporary units for evacuees, most of them in Iwaki. The first 1,600 apartments, however, are nine months behind schedule and will not be ready until 2017, officials say.