A container is designed to safely store radioactive debris from, for example, a nuclear reactor meltdown, in water or air. The container, with preferably although not necessarily all metal parts, has an overpack having an elongated cylindrical body extending between a top end and a bottom end, a planar bottom part at the bottom end, an open top at the top end, and a circular planar lid mounted over the open top. A basket is situated inside of the overpack. The basket has a plurality of elongated cylindrical canisters that are in parallel along their lengths. Each of the canisters has an elongated cylindrical body extending between a top end and a bottom end, a planar bottom part at the bottom end, an open top at the top end, and a circular planar lid mounted over the open top.