Another Day, Another Spill of Radioactive Water From Fukushima

A new day and a new spill of radioactive water Kimimasa Mayama/Pool/Reuters

The Fukushima nuclear plant is a relentless disaster. Another plume of radioactive water — the biggest in the last six months — has escaped from the plant, its operator Tepco announced Thursday. The 100-ton spill was traced to two valves left open by mistake, Tepco said.

Each liter of escaped water contains an average of 230 million becquerels (a unit of radioactivity) of particles emitting beta radiation, the New York Times reports. Half of the particles are likely strontium 90, which means the leak contains 3.8 million times the legal limit for drinking water. Strontium 90 can cause bone cancer and leukemia, and is absorbed by the human body much like calcium, the Times reports.

That's 46 times more radioactive than the groundwater near the plant, where contamination was disclosed earlier this month.

It is hard to comprehend the number of radioactive water accidents at Fukushima since an earthquake and tsunami crippled the plant in 2011. At a point last August, the Japanese government announced that roughly 330 tons (about 80,000 gallons) of radioactive water leaked into the Pacific Ocean from the Fukushima plant every day. The same month, experts feared that a vast underground reservoir of radioactive water was perilously close to reaching the ocean. The following October, radioactive water leaked while workers transferred water between two tanks. A few days later, Tepco announced a smaller amount of radioactive water had leaked into the ocean after workers miscalculated the capacity of the tank due to it sitting on a slope. The list goes on.

The evacuation and other drastic life changes prompted by the event is also taking a toll, especially on the elderly. More people have died of stress and other related conditions than from immediate injuries in the 2011 disaster, The Japan Times reported. While the long-term medical impact of elevated radiation in the area is largely unknown, 2,000 Fukushima workers face a heightened risk of thyroid cancer.

Concern over potential harm from the disaster has recently spread to the U.S. military. Over the past year, more than 70 U.S. sailors and Marines who were deployed to Japan in 2011 to aid tsunami victims have joined a billion-dollar lawsuit against Tepco. According to the suit, they suffered serious health issues after the mission, and allege that the company did not disclose information about the level of danger associated with radiation exposure near the nuclear plant.

Medical experts who spoke with CNN are skeptical of a connection between the soldiers' ailments and their mission, saying that it is too soon to attribute their illnesses to radiation. But plaintiffs like Lindsay Cooper and Kim Gieseking, who both say they've suffered from debilitating thyroid issues, are sure their time in Japan was the cause. Navy Officer Steve Simmons, another plaintiff in the case, lost all control of his legs a year after the mission. The Navy has acknowledged that the USS Ronald Reagan sailed through the nuclear plume, but maintain that it sailed far farther from the coast than the lawsuit alleges, according to CNN.