Chapter One
DANGEROUS WAVES
Atsufumi Yoshizawa was just finishing his shift at Japans Fukushima Daiichi nuclear plant. Two seawalls stretched into the Pacific Ocean like arms protecting the collection of turquoise-blue and white buildings. Yoshizawa, a nuclear engineer, helped run the plant, which produced electricity for millions of customers, including people in Tokyo, 177 miles (285 kilometers) away. It was a relaxed Friday afternoon, March 11, 2011. But the seafloor was restless.
The bottom of the sea is part of Earths crust, which is made of massive plates that fit loosely together like puzzle pieces. They usually slide past each other about as slowly as fingernails grow. But off the eastern coast of Japan, along a crack in the crust called a fault, the edges of two plates pushed against each other, locked in battle.
No one at Fukushima Daiichi was aware of the struggling undersea plates on March 11. It was business as usual at the plant. Since the 1880s many electrical plants have burned coal to make steam power to generate electricity. But uranium, a silvery metal made of atoms that split easily.
A satellite image of the Fukushima Daiichi nuclear plant was taken before disaster struck.
On this Friday afternoon, as Yoshizawa walked down a plant corridor, tremendous energy was about to be released but not inside the plants reactors. At 2:46 p.m., about 80 miles (129 km) off the coast, the seafloor rose violently. It was the epicenter of an earthquake.
Japan experiences more than 2,000 earthquakes a year, ranging from weak tremors to quakes that sway buildings. Sensors detect the traveling waves of motion and send warnings to TV and radio stations and cellphones. Students duck under desks, surgeons pause operations, and high-speed trains stop.
But It lasted five or six minutes. The magnitude 9.0 earthquake was one of the strongest ever recorded. Thousands of miles away, it caused water to slosh in Norways fjords and ice in Antarctica to crack. It shoved Japan about 8 feet (2.4 meters) east, and it even changed the way Earth spins.
Sensors at the plant triggered the automatic shutdown of fission inside Fukushima Daiichis three active reactors, units 1, 2, and 3. When the earthquake cut off electricity to the plant, generators switched on to keep lights and equipment running. Yoshizawa joined manager Masao Yoshida in the plants earthquake-proof bunker. They determined that the plants employees were safe, and the 40-year-old plant was undamaged.
The devastating tsunami that followed the magnitude 9.0 earthquake carried boats far inland.
But the jolting plates had disturbed the ocean. Large waves were traveling away from the epicenter of the earthquake. They approached Japans coast at 100 mph (160 kph). Almost an hour after the seawalls.
The huge oncoming tsunami hit Japan with tremendous force, sweeping away everything in its path.
Lights went out and machines went silent. Tsunami waves had flooded basements, destroying generators and electrical circuits. Plant engineer Water did not belong around the plants electronics. Yet it was essential inside reactors.
Electric pumps normally circulate water through the reactor containers to keep fuel rods from overheating. Even after fission is shut down, hot fuel rods need up to 24 hours to cool. Without working pumps to replace water thats 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 workers 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 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. Japans 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 Their dosimeters, machines to measure radiation, registered shockingly high radiation levels. Workers struggled with a valve, and by midafternoon steam leaked from unit 1s exhaust tower.
Just an hour later, relief turned to panic. As the containers 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 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 peoples mouths or lungs. Once inside the body, radiation damages living cells and destroys the 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 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 cant 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.