On March 11, 2011, a tsunami hit the Eastern coast of Japan. The Fukushima Daiichi nuclear plant was flooded, and on the following day, it began to leak radioactive fluid. Reactor 3 underwent full meltdown, with the fuel material melting through the reactor unit’s base. In other reactors, pressure of radioactive gases was building up. The operators made the decision to release the gas before the reactor units exploded. Hydrogen gas from the reactors exploded, propelling the radioactive material across the surrounding area.
In addition to this, the operators released the reactor coolant into the ocean. This radioactive fluid quickly spread throughout the surrounding ocean, and began to bioaccumulate in the organisms. Ocean currents have since then spread the radioactive water across the Pacific Ocean, all the way to the California coast.
The Fukushima disaster is the second worst nuclear disaster in history, contaminating massive quantities of ocean. Several years after the disaster, the radiation has spread out evenly across the entire Pacific Ocean, contaminating billions upon billions of gallons of water.