As reported by the Asahi Shimbun:
"The operator of the crippled Fukushima No. 1 nuclear power plant sat on its hands for more than two years despite having pledged to seal a leaking hole in a turbine building, The Asahi Shimbun has learned.
Tokyo Electric Power Co. said in April 2011, just one month after the Great East Japan Earthquake and tsunami triggered the Fukushima nuclear disaster, that it would block the connection between a turbine building and an underground pit to prevent radioactive water from leaking into the sea. However, the utility only began preparing for shielding tests this summer, after contaminated water was found to be leaking into the sea.
TEPCO's inaction is likely responsible for the spread of radiation...".