Mammoth Meltdown On March 11 2011 Japanese nuclear worker Takashi Sato wrote reports on his computer It was just another day at the Fukushima Daiichi nuclear power plant about 160 miles 267 kilometers northeast of Tokyo The skies were clear The sun shone But at 2 46 p m everything changed An enormous earthquake rattled Japan Centered 80 miles 129 kilometers offshore in the Pacific the Tohoku Earthquake measured 9 0 on the Richter Scale It shook buildings for a full five minutes sending workers ducking for cover 4
That colossal quake was just the beginning Forty-five minutes later a wall of water struck the shore engulfing the nuclear plant It was a tsunami American Carl Pillitteri who also worked at the plant said the wave was so massive it swept away the walls of the plant What Takashi and Carl did not know was that the earthquake and tsunami would kick off one of the worst nuclear disasters in history a meltdown China Russia North Korea Sea of Japan East Sea earthquake’s epicenter Sendai South Korea East China Sea Japan Fukushima Daiichi Pacific Ocean Japan sits in an area known as the Ring of Fire This part of the Pacific Ocean experiences frequent volcanic eruptions earthquakes and tsunamis The Tohoku Earthquake was one of many devastating earthquakes that have affected the country 5
After the initial earthquake workers rushing from buildings saw pipes bursting Some pipes carried water to cool three nuclear reactors The power went out plunging the entire plant into darkness Without power pumps couldn’t circulate cool water through the reactor When temperatures climb high enough the fuel rods melt This is a nuclear meltdown During a meltdown the fuel may melt through the floor and dump radioactive material into the ground or water or release it into the air Even after the nuclear reactions stop automatically as they did at Fukushima Daiichi nuclear cores stay hot Fast Fact At Fukushima temperatures reached 4,800 degrees Fahrenheit 2,649 Celsius A powerful explosion ripped the roof off reactor Number 1 at the Fukushima Dai-ichi nuclear power plant The meltdown damaged four of the six reactors at the plant beyond repair 6
Fortunately the power plant’s backup power system came on after the earthquake Diesel-fuel-powered generators switched on to make electricity and keep the cooling pumps operating Unfortunately those backup generators were located in the plant’s basement When the tsunami waves struck they ruined the generators Diesel generators use diesel fuel a form of gasoline to create electricity Aside from these bus-sized generators nuclear power plants in the United States also have portable steam generators 7
