need up to 24 hours to cool Without working pumps to replace water that’s boiling away to steam fuel rods heat so much that they can melt together This molten mass can burn through the protective container releasing life-threatening radiation into the air Meltdown is a nuclear plant worker’s nightmare Rushing around the dark control room with flashlights workers shared a single concern Were the fuel rods safe Without working gauges no one knew Plant manager Yoshida scrambled to make a plan What was happening was beyond what we trained for on a daily basis 5 a plant worker later explained He called it a race against time Workers collected car batteries to hook up to gauges Around 9 p m instruments came weakly to life with alarming news The water level inside unit 1 normally 20 feet 6 m above the fuel rods had dropped to just inches Meanwhile pressure soared as steam and gas filled the reactor vessel Unit 1 was a time bomb Yoshida planned to relieve the pressure the way a whistling teapot releases steam through a small opening Winds would carry radioactive steam over towns But an explosion inside the reactor vessel would release far more radiation Japan’s prime minister Naoto Kan ordered anyone living within 6 miles 10 km of the plant to evacuate People abandoned their search for loved ones in the tsunami-wrecked zone to flee a wave of radiation
The epicenter of the earthquake was 80 miles 129 km off the east coast of Japan Venting the reactor vessel is easy if the plant has electricity Workers simply open valves remotely from the control room On Saturday morning workers wearing gas masks and head-to-toe protective suits entered the reactor building to open valves by hand Yoshida feared that his men were a suicide squad 6 Their dosimeters machines to measure radiation registered shockingly high radiation levels Workers struggled with a valve and by midafternoon steam leaked from unit 1’s exhaust tower Just an hour later relief turned to panic As the container’s heat spiked to
5,072 degrees Fahrenheit 2,800 degrees Celsius more than half the surface temperature of the sun the zirconium coating around the uranium had produced explosive hydrogen gas AN INVISIBLE ENEMY Cameras captured frightening explosions in Fukushima Daiichi but not the greatest danger We were fighting an invisible enemy out-of-control reactors 7 engineer Takeyuki Inagaki remembered later It was like fighting a war Radiation absorbed by human tissue is measured in units called sieverts Most people are exposed to natural radiation of 2 or 3 millisieverts mSv a year On March 15 Fukushima Daiichi released its highest level of radiation 400 mSv per hour That is 20 times the annual exposure for uranium miners and employees in the nuclear industry Radiation in the form of visible light heat microwaves and radio waves moves through the air as harmless waves But the radiation inside a nuclear reactor is dangerous It is released by new elements that are created by fission during chain reactions Certain elements are unstable because they hold too much energy The excess energy radiates into the air Radiation waves can pass through the skin Radiation can also get into people’s mouths or lungs Once inside the body radiation damages living cells and destroys the genetic information inside them A single high dose can cause vomiting hair loss and bleeding gums But even small doses can cause cancer because radiation collects in the body A community-run lab about 40 miles 60 km from the Fukushima plant tracks radiation levels in soil water and food In universities data is handled by qualified students who have taken exams qualifying them to measure radiation Here it’s done by mothers working part-time It’s a crazy situation 8 said Kaori Suzuki director of Tarachine the nonprofit organization that runs the lab As ordinary citizens we had no knowledge about radiation at all All we knew was that it is frightening Suzuki said We can’t see smell or feel radiation levels Given this invisibility it was extremely difficult for us How do we fight it The only way is to measure it
A baby and her mother were scanned for radiation at a Fukushima evacuation center in March 2011 Houses that were swept out to sea by the devastating tsunami burned out of control in northeastern Japan Twenty-four hours earlier TV screens had broadcast video of dark seawater destroying the coast Now TV viewers watched the explosion at unit 1 Among them were Japan-based photojournalists who shoot images of unfolding news
