Neither the seismic event nor the megatsunami caused a release of radioactive material into waters at Fukushima. The failing of cooling because backup generators were flooded in the basement, leading to an explosion did. After that, they've released contaminated water into the ocean that can no longer be stored on site. Mistakes were made at Fukushima, but what radioactive waste release from seismic events is not what happened, and has never happened.