Timeline of the Fukushima Daiichi nuclear disaster pumps could be retrofitted to deliver concrete for that purpose. Prior to the elevation to level 7 by the Japanese authorities James Acton, Associate of the Nuclear Policy Program at the Carnegie Endowment for International Peace, was of the opinion that "Fukushima is not the worst nuclear accident ever but it is the most complicated and the most dramatic, was a crisis that played out in real time on TV. Chernobyl did not." A survey of radiation in seawater outside unit 2 shows radioactive isotope concentrations (iodine-131, caesium-134 and caesium-137) falling for the third consecutive day since the leak was
Fukushima Daiichi nuclear disaster On 13 February 2014, TEPCO reported 37 kBq (1.0 microcurie) of caesium-134 and 93 kBq (2.5 microcuries) of caesium-137 were detected per liter of groundwater sampled from a monitoring well. Dust particles gathered 4 km from the reactors in 2017 included microscopic nodules of melted core samples encased in caesium. After decades of exponential decline in ocean caesium from weapons testing fallout, radioactive isotopes of caesium in the Sea of Japan increased after Fukushima from 1.5 mBq/L to about 2.5 mBq/L and are still rising as of 2018, while those just off the western coast of Japan have declined. According