TOKYO (Kyodo) -- Japan's nuclear watchdog decided Wednesday to resume a probe into the cause of the 2011 meltdowns at the Fukushima Daiichi power plant after determining that radiation levels have fallen enough to allow investigators into the site.
The Nuclear Regulation Authority said it will seek to uncover whether one of the plant's reactors failed to properly vent radioactive steam, among other questions, and expects to report its findings before the end of 2020.
An interim report released in October 2014 based on investigations conducted from 2013 attributed the meltdowns of three reactors at the coastal plant to a tsunami which caused a catastrophic power loss that led to the failure of its cooling system.
The probe has since been suspended after it was deemed unsafe to enter some buildings in the plant operated by Tokyo Electric Power Company Holdings Inc.
The NRA said it will work with the Natural Resources and Energy Agency, which gives instructions to TEPCO on its decommissioning efforts, to ensure that the relevant facilities at the plant are preserved.