Unit 3 of the Fukushima Daiichi Nuclear Power Plant ( 福島第一原子力発電所3号機の建設 '' Fukushima Daiichi Genshiryoku Hatsudensho Sangoki no Kensetsu '' ) was one of the reactors in operation on 11 March 2011 , when the plant was struck by the tsunami produced by the Tohoku earthquake . In the aftermath , the reactor experienced hydrogen gas explosions and suffered a partial meltdown , along with the other two reactors in operation at the time the tsunami struck , unit 1 and unit 2 . Efforts to remove debris and coolant water contaminated with radiation are ongoing and expected to last several decades . The was a series of equipment failures , nuclear meltdowns , and releases of radioactive materials at the Fukushima I Nuclear Power Plant , following the Tōhoku earthquake and tsunami on 11 March 2011 . It is the largest nuclear disaster since the Chernobyl disaster of 1986
Tōhoku earthquake and tsunami
2011 Tōhoku earthquake and tsunami
Fukushima Daiichi nuclear disaster (Unit 3 Reactor)