Nevertheless, Japanese officials remained hopeful on Monday they could stick to their freshly minted "road map" for cleaning up the radiation leak and stabilising the plant by year's end so they could begin returning tens of thousands of evacuees to their homes.
"Even I had expected high radioactivity in those areas. I'm sure [Tokyo Electric Power Co (TEPCO), operators of the Fukushima Daiichi power station] and other experts have factored in those figures when they compiled the 'road map'," Yukio Edano, Japan's chief cabinet secretary, said.
Officials said on Monday that radiation had jumped in a water tank in Unit 2 and contaminated water was discovered in other areas of the plant, underscoring the growing list of challenges facing TEPCO in cleaning up and containing the radiation. They also described in more detail the damage to fuel in three troubled reactors, saying pellets had melted.
Workers have not been able to enter the reactor buildings at the plant since the first days after the cooling systems were wrecked by the March 11 earthquake and tsunami that left more than 27,000 people dead or missing in Japan's northeastern coast. (read more)