Learn more about our four-part investigative series on Fukushima's ongoing fallout.

At the Fukushima Daiichi plant, the Tokyo Electric Power Co., or TEPCO, is struggling to contain the ongoing nuclear disaster. Since the catastrophe almost three years ago, there has been disagreement about whether the plant is safe.

The official line from the Japanese government is that the situation is under control.

“The government is moving to the forefront and we will completely resolve the matter,” said Prime Minister Shinzo Abe in September, just before Tokyo was awarded the 2020 Summer Olympics.

But others, such as then–Tokyo Gov. Naoki Inose, have said the situation is “not necessarily under control.”

“The government must acknowledge this as a national problem so that we can head toward a real solution,” said Inose, in response to Abe’s comments.

“America Tonight” traveled to Fukushima to find out whether the world still needs to be worried.

“I think this is an ongoing crisis,” said David McNeill, a journalist who has lived in Japan since 2000 and has been covering the Fukushima disaster from the beginning. “What you’ve had is a series of ad hoc strategies designed to deal with the crisis that’s right in front of you.”

The events at Fukushima unfolded in a cascade of disasters, each one more frightening than the last: the massive earthquake and tsunami, the nuclear meltdowns, the explosions, the desperate attempts to keep fuel rods from overheating and, finally, the leaks of radioactive water into the Pacific Ocean.

Now, nearly three years later, the most pressing worry is the spent nuclear fuel rods, which are still precariously stored in a pool above the damaged and unstable Reactor 4. McNeill said there are thousands of nuclear fuel rods in Reactor 4, which must be extracted one by one. Last month TEPCO began the delicate, and dangerous, yearlong task of transferring those fuel rods — more than 1,300 in all, amounting to some 400 tons of uranium — to a safer location. Some experts have pointed out the serious risks of this process, McNeill said.

“For example, if there was another earthquake, another major earthquake, it could trigger another radioactive disaster,” he said.

But the real headache comes from the hundreds of tons of melted radioactive fuel in Reactors 1, 2 and 3. McNeill said that TEPCO only has “the vaguest idea” of where the molten fuel sits, and a constant flow of water is necessary to keep the molten uranium from heating up. TEPCO has built thousands of tanks to store the daily flood of contaminated water, but it is running out of space.

“The tanks have mushroomed all over the power plant,” McNeill said. “Because if they don’t keep it cool, it heats up, radiation escapes and then we’re back to square one.”

Aoyama’s take is very different from a map that’s making the rounds on social media, which claims to show radiation from Fukushima spreading throughout the Pacific. But it’s actually an altered map from the National Oceanic and Atmospheric Administration, tracing the tsunami’s path in 2011. American officials say there is no evidence of unsafe fish in the American food supply.

These reports are reassuring, but all bets are off if TEPCO doesn’t come up with a long-term strategy to plug the leaking plant.

“The whole system is all completely ad hoc,” McNeill said. “It’s been set up as an emergency for a situation that nobody ever predicted.”