Updated

Japan's tsunami-hit Fukushima power plant remains fragile nearly a year after it suffered multiple meltdowns, its chief said Tuesday, with makeshift equipment -- some mended with tape -- keeping crucial systems running.

An independent report, meanwhile, revealed that the government downplayed the full danger in the days after the March 11 disaster and secretly considered evacuating Tokyo.
Journalists given a tour of the Fukushima Daiichi plant on Tuesday, including a reporter from The Associated Press, saw crumpled trucks and equipment still lying on the ground. A power pylon that collapsed in the tsunami, cutting electricity to the plant's vital cooling system and setting off the crisis, remained a mangled mess.

Officials said the worst is over but the plant remains vulnerable.

"I have to admit that it's still rather fragile," said plant chief Takeshi Takahashi, who took the job in December after his predecessor resigned due to health reasons. "Even though the plant has achieved what we call 'cold shutdown conditions,' it still causes problems that must be improved."

The government announced in December that three melted reactors at the plant had basically stabilized and that radiation releases had dropped. It still will take decades to fully decommission the plant, and it must be kept stable until then.

The operators have installed multiple backup power supplies, a cooling system and equipment to process massive amounts of contaminated water that leaked from the damaged reactors.

But the equipment that serves as the lifeline of the cooling system is shockingly feeble-looking. Plastic hoses cracked by freezing temperatures have been mended with tape. A set of three pumps sits on the back of a pickup truck.

Along with the pumps, the plant now has 1,000 tanks to store more than 160,000 tons of contaminated water.

Radiation levels in the Unit 1 reactor have fallen, allowing workers to repair some damage to the reactor building. But the Unit 3 reactor, whose roof was blown off by a hydrogen explosion, resembles an ashtray filled with a heap of cigarette butts.

A dosimeter recorded the highest radiation reading outside Unit 3 during Tuesday's tour -- 1.5 millisieverts per hour. That is a major improvement from last year, when up to 10 sieverts per hour were registered near Units 1 and 2.

Exposure to more than 1,000 millisieverts, or 1 sievert, can cause radiation sickness including nausea and an elevated risk of cancer.

Officials say radiation hot spots remain inside the plant and minimizing exposure to them is a challenge. Employees usually work for two to three hours at a time, but in some areas, including highly contaminated Unit 3, they can stay only a few minutes.

Since the March 11 crisis, no one has died from radiation exposure.

Tuesday's tour, organized by plant operator Tokyo Electric Power Co., or TEPCO, came as an independent group released a report saying the government withheld information about the full danger of the disaster from its own people and from the United States.

The report by the private Rebuild Japan Initiative Foundation delivers a scathing view of how leaders played down the risks of the reactor meltdowns while holding secret discussions of a worst-case scenario in which massive radiation releases would require the evacuation of a much wider region, including Tokyo. The discussions were reported last month by the AP.

The report, compiled from interviews with more than 300 people, paints a picture of confusion during the days immediately after the accident. It says U.S.-Japan relations were put at risk because of U.S. frustration and skepticism over the scattered information provided by Japan.

The misunderstandings were gradually cleared up after a bilateral committee was set up on March 22 and began regular meetings, according to the report.

It credits then-Prime Minister Naoto Kan for ordering TEPCO not to withdraw its staff from the plant and to keep fighting to bring it under control.

TEPCO's president at the time, Masataka Shimizu, called Kan on March 15 and said he wanted to abandon the plant and have all 600 TEPCO staff flee, the report said. That would have allowed the situation to spiral out of control, resulting in a much larger release of radiation.

A group of about 50 workers was eventually able to bring the plant under control.

TEPCO, which declined to take part in the investigation, has denied it planned to abandon Fukushima Dai-ichi. The report notes the denial, but says Kan and other officials had the clear understanding that TEPCO had asked to leave.

But the report criticizes Kan for attempting to micromanage the disaster and for not releasing critical information on radiation leaks, thereby creating widespread distrust of the government.

Kan said he was grateful the report gave a favorable assessment of his decision to prevent TEPCO workers from abandoning the plant.

"I give my heartfelt respects to the efforts of the commission," he said in a statement. "I want to do my utmost to prevent a recurrence."

Kan has acknowledged in a recent interview with AP that the release of information was sometimes slow and at times wrong. He blamed a lack of reliable data at the time and denied the government hid such information from the public.

The report also concludes that government oversight of nuclear plant safety had been inadequate, ignoring the risk of tsunami and the need for plant design renovations, and instead clinging to a "myth of safety."

"The idea of upgrading a plant was taboo," said Koichi Kitazawa, a scholar who heads the commission that prepared the report. "We were just lucky that Japan was able to avoid the worst-case scenario. But there is no guarantee this kind of luck will prevail next time."