The No . 6 unit appears safe , for now , Nishiyama said . The Nos . 1 and 3 reactors are prime reactors at the northeastern Japan plant . Authorities are trying to determine the source of an apparent leak in reactor No . 3 . An official says No . 1 seems ` ` rather stable '' after challenges with temperature and pressure .
The Nos . 1 and 3 reactors are prime reactors at the northeastern Japan plant . Authorities are trying to determine the source of an apparent leak in reactor No . 3 . An official says No . 1 seems ` ` rather stable '' after challenges with temperature and pressure .