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Decades of complications and cleanup remain at Japan's Fukushima nuclear plant

The Unit 1 reactor at the Fukushima Daiichi Nuclear Power Station was the first to blow after it overheated and produced a lethal cloud of hydrogen gas in March 2011. The explosion reduced the reactor building to a shell; workers have capped it to contain the radiation inside.

COURTESY OF TEPCO

By SETH ROBSON | STARS AND STRIPES Published: December 17, 2014

FUKUSHIMA DAIICHI NUCLEAR POWER STATION, Japan — The Fukushima Daiichi Nuclear Power Station disaster may be the ultimate challenge for neatness-obsessed Japan.

“Cleansing” the power plant and the surrounding area is expected to take three decades as engineers wrangle with complications that include keeping contaminated water from reaching the sea and storing not only radioactive material, but the gear used to remove it, which becomes radioactive, too.

TIMELINE | Disaster strikes Japan

On March 11, 2011, the seaside power station was hit by a magnitude-9 earthquake and a 45-foot-high tsunami that damaged four of its six reactors. Two exploded, contaminating large swathes of eastern Japan, in the worst nuclear disaster since Chernobyl in 1986.

Thousands of white-suited workers are still struggling to contain the environmental impact, a task as complex as the nuclear reactions that caused the accident.

A tour of the plant last week started at the edge of a 12-mile exclusion zone where radioactivity has forced tens of thousands of residents to evacuate.

J Village, on the southern edge of the zone, was a soccer training facility before the earthquake struck. After the plant explosions, it became a staging area for emergency crews to put on protective gear before heading north. It still serves the same purpose; clean-up crews park on the soccer fields each morning before boarding buses to the plant.

Their employers are keen to trumpet the clean-up effort. The side of one of the buildings at J Village looks like a sponsors wall at a sports event with the logos of companies involved in the work, including those which supplied the Fukushima reactors: Toshiba, Hitachi and General Electric.

The plant’s former operator, Tokyo Electric Power Co. (TEPCO), measures background radiation levels in the exclusion zone in microsieverts, which gauge the risk of radiation absorbed by the body. At J Village, radiation levels are only 0.1 microsieverts per hour — less than natural background radiation in many parts of the world.

The road from J Village to the plant passes a 7-Eleven convenience store serving coffee and snacks to those working in the exclusion zone. To the north lie towns abandoned since the disaster.

Houses in the southern part of the exclusion zone are in good condition. The relatively low level of contamination here means former residents can visit their properties during the day, according to Nakayama Tadashi, a TEPCO visitor guide.

The fields are no longer farmed, but they’ve been “cleansed” — contaminated topsoil has been removed and stored in large plastic bags that are clumped together under green netting at 20 different storage sites, each the size of several football fields.

At Naraha village, buildings show damage from the 2011 disaster, but six miles from the reactors, the radiation level still registers only 0.1 microsieverts.

Just up the road, in the town of Tomioka, the level is 0.3 microsieverts — not enough to be much of a hazard to construction workers fixing the damaged buildings. Nearby there’s a turn-off for the Fukushima Daini Nuclear Power Station. The facility was also struck by the tsunami, but workers managed to stabilize the reactors, averting a second disaster.

Near the shore, Tomioka’s train station was destroyed by the tsunami, but much of the town is further inland and still standing.

The next town is Okuma. Residents fled on short notice the day of the disaster. At 3.5 miles from the damaged plant, it’s not safe to go back. Cleansing hasn’t begun here yet.

Mannequins collect dust in shop windows, and vines creep over abandoned homes. Vehicles rust in driveways. A wading bird in a small stream was the only sign of animal life, although there are head-high weeds at the golf driving range and surrounding rice paddies.

Near the turn-off for the power station, radiation levels are 10 microsieverts — 100 times higher than at J-Village.

“It’s a hot spot,” Tadashi explains.

Getting into the plant involves a security check and protective gear. In some areas, that means a white hazmat suit, gloves and a surgical mask. Those working in more contaminated places use full facemasks and air filters. Some workers toil here for less than $1,700 a month.

The work site is a maze of plastic pipes, earthworks, wet concrete, cranes, cables and wires. Hundreds of concrete boxes store radioactive objects removed from the reactors. Massive tanks of radioactive water stand where a forest has been cut. The contaminated timber is stacked north of the reactors.

The challenges in the cleanup are legion.

Many relate to water being used to cool melted nuclear fuel inside the wrecked reactor buildings. The earthquake cracked the structures, so the cooling water seeps out and ground-water seeps in. Each day, hundreds of tons of contaminated water are collected and stored in massive tanks, some of which leak, too.

TEPCO’s solution involves diverting ground water around the reactors and removing radioactivity from the cooling water so it can be recycled. The company is also building an “ice wall” that will freeze soil under the reactors to keep contaminated water from leaking into the sea.

The reactor buildings loom like monoliths over the facility. Each has its own character — and its own challenges.

At the time of the earthquake, three of the reactors were shut down for maintenance. The three that were operating shut down automatically, but the tsunami damaged systems needed to cool the uranium that powered them.

Unit 1 was the first to blow after it overheated and produced a lethal cloud of hydrogen gas. The explosion reduced the reactor building to a shell; workers have capped it to contain the radiation inside.

Unit 2 also overheated, but the gas was able to escape through a doorway, averting an explosion. The large blue-and-white building that houses it looks normal.

Unit 3 exploded, destroying the top 50 feet of the building. Workers use tall cranes to remove radioactive debris.

It’s possible to drive right up to the building that houses Unit 4, which was shut down for maintenance but still sustained damage from an explosion of gas from pipes connected to Unit 3. Workers started removing spent fuel in November and hope to finish by the end of the year. Last Thursday, the radiation level here was 45 microsieverts, but TEPCO says it can spike as high as 100.

Many of the vehicles used at the plant don’t have license plates. They are so contaminated that they can never leave. On-site workshops and filling stations keep them running.

At the waterfront, in front of the reactors, thousands of concrete “tetrapods” have been stacked on top of an old breakwater to provide additional protection from future tsunamis.

robson.seth@stripes.com
Twitter: @SethRobson1

Contaminated water is one of the biggest challenges for white-suited workers cleaning up pollution at the Fukushima Daiichi Nuclear Power Station. The site is tangled with a vast array of pipes designed to prevent radioactive water from leaking into the ground.
COURTESY OF TEPCO

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