Kazuo Ouchi drives down a single-lane road through sheets of rain until he reaches a gravel driveway leading to a weathered farmhouse. Yellowing lace curtains are drawn tight over the windows, shutting out the weak winter light.

"Sorry about the dark," Ouchi says, stepping over children's toys. "I shut off the electricity a while ago."

Ouchi is back in his hometown of Iitate, a village in Fukushima Prefecture. His two-story house has sat empty for nine years after a massive earthquake and tsunami triggered meltdowns at a nuclear plant 48 km (30 miles) away, spewing radiation into the air and forcing the entire village to evacuate.