Japan quake causes emergencies at 5 nuke reactors

Japan declared states of emergency for five nuclear reactors at two power plants after the units lost cooling ability in the aftermath of Friday's powerful earthquake. Thousands of residents were evacuated as workers struggled to get the reactors under control to prevent meltdowns. A single reactor in northeastern Japan had been the focus of much of the concern in the initial hours after the 8.9 magnitude quake, but the government declared new states of emergency at four other reactors in the area Saturday morning. The earthquake knocked out power at the Fukushima Daiichi plant, and because a backup generator failed, the cooling system was unable to supply water to cool the 460-megawatt No. 1 reactor. Although a backup cooling system is being used, Japan's nuclear safety agency said pressure inside the reactor had risen to 1.5 times the level considered normal. Authorities said radiation levels had jumped 1,000 times normal inside Unit 1 and were measured at eight times normal outside the plant. They expanded an earlier evacuation zone more than threefold, from 3 to 10 kilometers (2 miles to 6.2 miles). Some 3,000 people had been urged to leave their homes in the first announcement.The government declared a state of emergency, its first ever at a nuclear plant. And plant operator Tokyo Electric Power Co. warned of power shortages and an "extremely challenging situation in power supply for a while." 

The utility, which also operates reactors at the nearby Fukushima Daini plant, later confirmed that cooling ability had been lost at three of four reactors there, as well as a second Fukushima Daiichi unit. The government promptly declared a state of emergency there as well. The reactor core remains hot even after a shutdown. If the outage persists, it could in a worst-case scenario cause a reactor meltdown, an official with Japan's nuclear safety agency said on condition of anonymity, citing sensitivity of the issue. 

Japan Nuclear and Industrial Safety Agency official Ryohei Shiomi said radiation levels surged inside the control center at the Fukushima Daiichi No. 1 reactor, while a monitoring device at the front gate of the compound detected radiation that is eight times higher than normal. The level outside the 40-year-old plant in Onahama city, about 170 miles (270 kilometers) northeast of Tokyo, is still considered very low compared to the annual exposure limit, Shiomi said. It would take 70 days of standing at the gate to reach the limit, he said.