Damage at a nuclear power plant has made leaking radiation the primary threat facing a country grappling with devastation from a 9.0-magnitude earthquake and tsunami
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Water from units 1-4 has contaminated adjacent seawater with iodine-131 and cesium-137. Engineers are processing about 60,000 tons of contaminated water found in the turbine buildings of units 1, 2 and 3, diverting it to reactor condensors and temporary storage tanks, with plans to send it to a radiation waste treatment facility before discharging the water into the sea |
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Effects of radiation A blast of radiation often causes immediate, obvious symptoms, but damage from low levels of exposure -- generally 100 mSv or less -- may not appear for decades, if ever. Japanese officials have set a dose limit of 250 mSv for nuclear workers during emergencies. |
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Evacuation
Japanese officials expanded the evacuation zone from 12.5 miles to 19 miles on March 25.
This article was first published in Washington Post
