New photographs show what may be melted nuclear fuel sitting under one of Japan’s wrecked Fukushima reactors, a potential milestone in the search and retrieval of the fuel almost six years after it was lost in one of the worst atomic disasters in history.
Tokyo Electric Power Co. Holdings Inc., Japan’s biggest utility, released images on Monday showing a grate under the Fukushima Dai-Ichi No. 2 reactor covered in black residue. The company, better known as Tepco, may send in a scorpion-like robot as soon as February to determine the temperature and radioactivity of the residue.
Finding the location “will let them know how much material is there, the configuration of the material, and then they can determine the best way to remove it,” Dale Klein, an adviser to Tepco and a former chairman of the U.S. Nuclear Regulatory Commission, said in an interview in Tokyo. “The fact that they accomplished this technical objective is good.”
Using a team that worked remotely and on site, the utility guided a camera through a hole drilled into a wall obstructing access to the reactor’s primary containment vessel.
If confirmed, the photographs would provide the first view of the fuel melted during the triple reactor accident at Fukushima almost six years ago. For Tepco, which bears most of the clean-up costs, the discovery would help the utility design a way to remove the highly-radioactive material.
Decommissioning the reactors will cost 8 trillion yen ($70.4 billion), according to an estimate in December from the Ministry of Economy, Trade and Industry. Removing the fuel is one of the most important steps in a cleanup that may take as long as 40 years.
The unprecedented nature of the Fukushima disaster means that Tepco is pinning its efforts on technology not yet invented to get the melted fuel out of the reactors.
The company aims to decide on a fuel removal procedure for the first reactor during the fiscal year ending March 2019, and to begin removing fuel in 2021.