How dangerous is the Fukushima nuke plant today?

OKUMA, Japan (AP) – A decade ago, a massive tsunami crashed at the Fukushima Daiichi nuclear power plant. Three of the reactors have melted and it looks like a bombed factory. Emergency workers have risked their lives to try to prevent one of the worst nuclear crises in history from getting out of control.

Proper equipment has now replaced struggling plastic hoses held in place with adhesive tape and an outside power switch board contaminated by rats, causing eclipse. Radiation levels have dropped, enabling workers and visitors in most areas to wear ordinary clothing and surgical masks.

But deep inside the plant there is still danger. Officials do not know exactly how long the cleanup will take, whether it will be successful and what could become of the land where the plant sits.

Journalists from The Associated Press recently visited the factory to document its progress in clearing up on the 10th anniversary of the collapse and the challenges ahead.

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WHAT HAPPENED 10 YEARS AGO?

After a magnitude 9.0 earthquake on March 11, 2011, a 17-meter-high tsunami struck the coastal plant, destroying power supply and cooling systems and destroying reactor no. 1, 2 and 3.

The three other reactors at the plant were offline and survived, although a fourth building along with two of the three molten reactors had hydrogen explosions, which caused massive radiation and caused prolonged contamination in the area.

The plant’s operator, Tokyo Electric Power Co., said the tsunami could not be foreseen, but government reports and independent investigations and recent court decisions have made the plant a disaster as a human being and, due to safety negligence, lax supervision. describe. by regulators and collusion.

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WHAT’S INSIDE THE MELTING REACTORS?

About 900 tons of molten nuclear fuel remains inside the three damaged reactors, and their removal is a daunting task that, according to officials, will take 30-40 years. Critics say this is too optimistic.

Separate attempts to remove spent fuel from cooling baths in the reactor buildings are hampered by high levels of radiation and debris and have been delayed for up to five years. If the plant’s pools lose their cooling water in another major earthquake, exposed fuel rods can quickly overheat and cause an even worse collapse.

The molten cores in units 1, 2 and 3 mostly fell to the bottom of their primary containers, some of which penetrated and mixed with the concrete foundation, making removal extremely difficult.

Remote controlled robots with cameras gave only a limited picture of the molten fuel in areas that are still too dangerous for humans to navigate.

The head of the plant, Akira Ono, says the inability to see what is happening inside the reactors means that the details of the molten fuel are still unknown.

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ARE there any underground leaks?

Since the disaster, polluted cooling water has continuously escaped from the damaged primary vessels in the basement of the reactor building, where it mixes with groundwater flowing in. The water is pumped and treated. A portion is recycled as cooling water, while the rest is stored in 1,000 large tanks.

Early in the crisis, highly contaminated water that leaked from damaged basements and maintenance ditches escaped into the ocean, but the main leaks were closed, TEPCO said. Tons of contaminated sandbags used to prevent the leaks early in the disaster remain in two basements.

Small amounts of radiation are still leaking into the sea and elsewhere through underground passages, although the amount is small today and fish caught on the coast are safe to eat, scientists say.

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WHAT HAPPENS TO THE DISTURBED RADIOACTIVE WATER?

The 1,000 tanks are filled with treated but still radioactive water towers over workers and visitors to the plant.

TEPCO says the storage capacity of the tanks of 1.37 million tons will be full in 2022. A government panel recommendation that the water be released into the sea is being harassed by locals, especially fishermen who are concerned about further damage to the area’s reputation. A decision on the recommendation is pending.

TEPCO and government officials say tritium, which is not harmful in small amounts, can not be removed from the water, but all other isotopes selected for treatment can be reduced to safe levels.

TEPCO has managed to reduce the amount of polluted water to one third of what it was through a series of measures.

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WHAT IS IT TO VISIT THE PLANT?

The first thing visitors see is a stylish office building that houses the TEPCO dismantling unit.

In another building, factory workers – now about 4,000 a day – go through automated security checkpoints and radiation measurements.

Because the radiation levels dropped significantly after the disinfection, complete protective equipment is only needed in a few places in the plant, including in and around the molten reactor buildings.

On a recent visit, AP journalists donated partial protective gear to cover an area with low radiation: a helmet, double socks, cotton gloves, surgical masks, goggles and a vest with a personal dosimeter.

Complete protective equipment, which means a shadow cover, a face mask, a head covering, triple socks and double rubber gloves, is required at a shared storage pool where fuel removal from the reactor pool no. 3 was recently completed.

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WHAT ARE THE ENDGAME?

A decade after the crash, Japan still has no plan to dispose of the highly radioactive molten fuel, debris and debris at the plant. Technology is also not yet advanced enough to manage the waste by reducing its toxicity.

TEPCO says they need to get rid of the water storage tanks to free up space at the plant so workers can build facilities used to study and store molten fuel and other waste.

There are about 500,000 tons of solid radioactive waste, including contaminated rubbish and soil, sludge from water treatment, scrapped tanks and other waste materials.

It is unclear what the plant will look like if the work is done there. Local officials and residents say they expect the complex to one day be an open space where they can walk freely. But there is no clear idea whether or when this could happen.

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Tokyo correspondent Mari Yamaguchi has visited the Fukushima nuclear power plant nine times since 2012.