(x)"waste" means unusable unserviceable movable property, including solid, liquid and gaseous matter, which the possessor or generator wants to discharge, or the controlled disposal of which is called for in order to preserve public welfare and in particular, the protection of the environment; or residual radioactive matter or radioactive components of disassembled or dismantled facilities, the controlled disposal of which shall be made in accordance with the Atomic Energy Act, 1962.