Four nuclear power plants located on the eastern coastline close to the epicenter were affected: Onagawa (3 reactors), Fukushima-Daiichi (6 reactors), Fukushima-Daini (4 reactors) and Tokai (1 reactor). These reactors are all using boiling water technology, and enter services in the 1970s and 1980s.
The next nearest nuclear power plant is Kashiwazaki-Kariwa (7 reactors) that sits on the opposite site of Honshu island (the main Japanese island, where Tokyo is), on its western coast.
Fukushima-Daiichi (operated by TEPCO):
Fukushima-Daini (operated by TEPCO):
Onagawa (operated by Tohoku):
Tokai 2 (operated by Japco):