TOKYO — The utility that operates Japan’s crippled atomic plant said Friday that it deserves most of the blame for the country’s nuclear crisis, in its strongest remarks about its own shortcomings.
Tokyo Electric Power Co. acknowledged in a report that it was not adequately prepared to deal with the massive earthquake and tsunami that ravaged northeastern Japan in March 2011.
The twin disasters cut power at TEPCO’s Fukushima Dai-ichi nuclear plant, causing meltdowns at three reactors. Massive radiation leaks contaminated air, water, and soil around the plant, forcing about 160,000 residents to evacuate.
‘‘Our safety culture, skills, and ability were all insufficient,’’ TEPCO president Naomi Hirose told a news conference. ‘‘We must humbly accept our failure to prevent the accident, which we should have avoided by using our wisdom and human resources to be better prepared.’’
The report said TEPCO’s equipment and safety provisions were inadequate and that the meltdowns should have been avoided. TEPCO said it was complacent about safety measures and delayed upgrading them until after the accident. It also said TEPCO didn’t adequately inform the public of risks and troubles at the plant.
The acknowledgment is a major reversal from TEPCO’s initial investigation report.
In the June 2012 report, TEPCO maintained that the tsunami was mostly to blame for the world’s worst nuclear disaster since Chernobyl in 1986. It defended its crisis management and criticized excessive interference from the prime minister’s office.
After the company’s reluctance to come to terms with its responsibility triggered public outcry, it launched an internal reform task force, led by Hirose, to reinvestigate the crisis.
The task force was overseen by a five-member committee of outside experts, including former US Nuclear Regulatory Commission chief Dale Klein.
In October, TEPCO acknowledged that it underestimated the tsunami risk and could have mitigated the impact of the accident if it had backup power and cooling systems and trained employees with practical crisis management skills.
Friday’s report urged TEPCO to introduce effective training programs and oversight by outside experts.