Robot finds likely melted nuclear fuel deposits inside Fukushima reactor

TOKYO – Images captured by an underwater robot showed massive deposits believed to be melted nuclear fuel covering the floor of a damaged reactor at Japan's crippled Fukushima nuclear plant. The robot found large amounts of solidified lava-like rocks and lumps in layers as thick as 3 feet on the bottom inside of a main structure called the pedestal that sits underneath the core inside the primary containment vessel of Fukushima's Unit 3 reactor, said the plant's operator, Tokyo Electric Power Co. On Friday, the robot spotted suspected debris of melted fuel for the first time since the 2011 earthquake and tsunami caused multiple meltdowns and destroyed the plant. The three-day probe of Unit 3 ended Saturday. Locating and analyzing the fuel debris and damage in each of the plant's three wrecked reactors is crucial for decommissioning the plant. The search for melted fuel in the two other reactors has so far been unsuccessful because of damage and extremely high radiation levels.