KAMAISHI, Japan, (AFP) - Workers were close to restoring power to a nuclear plants overheating reactors Sunday as the toll of dead or missing from Japans worst natural disaster in nearly a century neared 21,000. Amid the devastation on the northeast coast left by a March 11 quake and tsunami, police reported an astonishing tale of survival with the discovery of an 80-year-old woman and her 16-year-old grandson alive under the rubble. They were in the kitchen when their house collapsed but the teenager was able to reach food from the refrigerator, helping them survive for nine days, broadcaster NHK quoted rescuers as saying. But with half a million tsunami survivors huddled in threadbare, chilly shelters and the threat of disaster at the Fukushima No. 1 nuclear plant stretching frayed nerves, the mood in the worlds third-biggest economy remained grim. Food contaminated with radiation was found for the first time outside Japan - where milk and spinach have already been tainted by a plume from Fukushima - as Taiwan detected radioactivity in a batch of imported Japanese fava beans. The discovery of traces of radioactive iodine in Tokyo tap water, well to the southwest of the crippled atomic power plant on the Pacific coast, compounded public anxiety but authorities said there was no danger to health.