It rises from springs in the peaks of the Nasu Mountains . It collects water from tributaries leaving the Å u Mountains and the Abukuma Highlands ( é æ é é `` å ) . It runs through Fukushima Prefecture and Miyagi Prefecture , rising from springs in the peaks of the Nasu Mountains , collecting water from tributaries leaving the Å u Mountains and the Abukuma Highlands , then emptying into the Pacific Ocean as a major river .