Ian Williams / NBC News

Junko Takashi, 79, stands outside her temporary home in the tsunami-devastated town of Otsuchi, Japan. All of the town's residents over 65 have a yellow flag they put out in the morning and take down in the evening. If no flag appears in the morning, then officials come and check on them.

OTSUCHI, Japan – When 79-year-old Junko Takashi saw the tide fast receding in the bay below her house, she remembered the warnings of her mother and her grandmother, that this was a sign of a tsunami.

But still she hesitated.

"I lived on high ground, on the hillside," she said. "I never thought the water could reach here."

She decided to take no chances, and leaving all her belongings behind her, she climbed to higher ground. She didn't see the tsunami rolling in, but remembers the terrible noise – like a waterfall, only far, far louder, she recalled.

By the time it was over, all that was left of her house were its foundations.

Some 70 percent of her town, Otsuchi, was destroyed and 10 percent of the town’s population of 16,000 are dead or missing. Its fishing industry, the backbone of the local economy, was obliterated.

Yellow flag marks sign of life
One year on and Takashi lives in a temporary home, consisting of a tiny living room, narrow kitchen and bathroom. It's one of a cluster of 80 temporary homes erected on the outskirts of what remains of Otsuchi.

She lives alone, her belongings neatly arranged in little cubicles around her. We could barely squeeze into her living room as she pointed to the television, fridge, microwave and heater, all donated by charities who were at the forefront of a massive aid operation in the weeks and months after the disaster.

Toru Yamanaka / AFP - Getty Images

This combination of pictures from Otsuchi, Japan shows a catamaran sightseeing boat washed by the tsunami onto a two-storey home on April 16, 2011 (top) and the same area on January 16, 2012 (bottom). Click on the photo to see a SLIDESHOW of before and after pictures.

Now much of that initial support has gone. "We're on our own now," she said.

"You've got to be positive. I am 79-years-old, who knows how many years I have left."

She told me that before the tsunami she was pretty self-sufficient, since she had land to grow all the vegetables she needed, and her two brothers were fishermen. Now she had to buy everything with her pension, while trying to save for an uncertain future.

But free temporary housing, in which 2,000 of Otsuchi's people now live, is only available for two years.

Outside her home, and outside those of many of her neighbors, flutters a little yellow flag. I asked her what that was for.

"They are for everybody over 65 and living alone," she replied. They are asked to put the flags out in the morning and take them down in the evening. If no flag appears in the morning, then officials will come and check on them.

Ian Williams / NBC News

A mountain of debris in the Japanese town of Otsuchi.

Mountains of debris and uncertain plans
Otsuchi appears to have made great strides in cleaning up the twisted wreckage that was once their town, and removing the fishing boats flung inland.

Looking down from the surrounding hills and all you see is a flat plain with a dusting of snow, just the foundations marking where buildings used to stand.

But the remains of the town has essentially been scooped up and piled into vast mountains of debris, which will take years to dispose of.

Takashi believes she will be allocated a new apartment once she leaves her temporary home, but the town of Otsuchi has been slow to draw up plans for the future. There is still no blueprint for what will replace a town virtually wiped from the map.

The local mayor has pledged to build a new 50-foot high seawall, more than twice the height of the one tossed aside by the tsunami. But there is no agreement as to where any new town will be built, nor how it can be made economically viable.

Elderly people, who dominate many of these small coastal towns, are wary of grand plans for new (and more economically sustainable) towns. They form an important political group.

"I want to live where I used to live," Takashi said. "I was comfortable there."

Staying positive
The future looks daunting, but Takashi is remarkably upbeat, showing me photos of some of the charity workers and celebrities who have visited over the months.

"I like visitors. I like to talk with people," she said.

"It's always been my policy to be positive about what lies ahead."

By Richard Engel
NBC News Chief Foreign Correspondent

It’s what an insurance company might call “a write-off” – a place that seems beyond salvation, and certainly too expensive to fix. I’d never thought of land that way. You smash up a car, and then it’s compacted into a square and maybe even recycled. Finito. But land? 

Last year, Japan’s disaster at the Fukushima nuclear power plant contaminated the land around it so badly that the area was effectively a write-off.  It’s been excised from terra cognita, uninhabitable, unwanted. Today the radiation-infected area is known by a name Ray Bradbury would like: “the exclusion zone.” 

With radiation detectors clipped to our white hazmat suits, we drove into this decimated pocket of our planet. 

Before we could get inside, a policeman stopped our car. There are checkpoints all around the exclusion zone, which extends in a twelve-mile radius around the crippled Fukushima nuclear power plant. 

The people who lived in the zone left in a hurry. They had no time to pack up their homes and businesses. Only recently, and with special permission, the Japanese government has allowed former residents to return to collect family heirlooms, important documents or equipment. The former residents are only permitted to stay for a few hours. It’s a grab-and-go operation.

We joined a man who was returning to his factory to pick up expensive cutting tools he needed to manufacture electronic components. Without the machines, he can’t run his business.   

The man showed the police officer at the checkpoint his identification and permission. With a polite and decisive wave, the officer let us pass. We drove into the zone.

Suburban scenes
When I first imagined the exclusion zone, I pictured a desolate open-air microwave. I thought of burned trees, scorched earth, crumbed houses. Maybe it was the name that conjured up the image of a nuclear wasteland. I had movie-fed visions of the radiation leaving me glowing. Friends, only half in jest, offered suggestions as to how I could use tin foil to protect myself and potential progeny.

But the exclusion zone didn’t look like that at all. Instead, it was a suburbs-fringed town surrounded by cattle farms. There were neat three- and four-bedroom houses on half-acre plots. There were tricycles and big-wheels on the driveways. There were swing sets in the yards. The only thing missing was people. If space travelers arrived after an extinction-level event, this is what they might find. A traffic light on the main street blinking red cautioned drivers who weren’t there to slow down.

I walked down the center of the street. It’s an odd feeling to walk down the middle of a main street, down the dotted line. I walked into a large drug store. The door was open. It was an American-style drugstore that sold everything from candy bars to razors to toilet paper. The shelves were still stocked. There were half-filled baskets in the aisles. It was silent. No people. No cash registers. No background music. Nothing.

A sushi restaurant was next door. It was locked. The menu on the front window showed the lunch special, a combo of sushi and miso soup, that was offered on the day of the explosion.

I walked into a man’s home. I opened his fridge. It was full. The food was rotten. 

There was a laundromat nearby. There were carts half full of clothing in front of the washing machines. 

But suddenly we heard movement. Cows, which have broken out of their enclosures, have taken over the town. They seemed more wild and aggressive than usual. The cows were led by bulls. We had to hide behind a tree as the bulls raced past, cows charging behind them. They ran so quickly I saw a cow slip on the street and crash into storefront. She scampered to her feet and joined the feral herd.

Good schools
The town is Okuma. A year ago it had a population of around 10,000. It was a fairly wealthy community, not rich but comfortable middle-class. It had some of the best schools in the area. There was a popular softball league. A lot of people worked as engineers and technicians at the nearby nuclear plant.

The radiation levels are high in Okuma, but I learned that the real danger is the dust. Don’t touch your eyes in the exclusion zone. Don’t rub your mouth. Don’t pick your nose. And never, under any circumstances, eat anything at all. 

When the Fukushima plant was destroyed, billions of microscopic particles of radioactive cesium were shot into the sky like a volcano belching ash. The cesium mixed with steam into what were effectively radioactive clouds. Then, it started to snow. The snow brought the cesium to the ground. 

The cesium is still all around, even though you can’t see it. It’s on the trees, on the roads and on the houses. It’s on the cows, and it’s in the cows. It’s in the wood and the dirt and the worms. Every time it rains, the cesium moves around. It’s in the water too.

We were dressed in white oversuits. They don’t do much to protect against radiation per se -- they’re not made of lead like the blankets that cover you during x-rays – they’re more like waterproof slickers. They zip up to your chin and down to your shoes, all in an effort to keep off the dust particles. The tiny cesium particles are light enough that if you stir up dust as you walk, the cesium will swirl in the air. You don’t want to breathe it in.

Deadly particles
During our trips into the zone – we went three times – we used radiation detectors to test different areas. Radiation isn’t constant. It all depends on the particles. Where they collect, there’s more radiation.

Paved surfaces generally had low levels of radiation. The wind blows off the dust from the smooth pavement. Our detectors showed that the grass and bushes had much higher concentrations. The plants grab the dust. Gullies, depressions and gutters were even worse, since the cesium tended to collect there. The feral cow dung was bad, too. I thought of all the cesium in their stomachs and intestines and throats. Don’t step in the dung in the exclusion zone.

An exclusion zone, of course, is just a line. The radiation doesn’t stop at the checkpoint. Fukushima City is just 40 miles away. With a population of about 300,000, it was never evacuated. Cesium fell on Fukushima too.  But instead of abandoning the city, the government is trying to clean it up. It is a monumental task.  

It is like dusting every nook and crack in a city to remove an invisible powder. So how do you even try?

A lawn buried
First, the city will hose down your roof to wash off the particles. They use high-power hoses, like the ones window washers use to reach upper floors. Then, you or a city official cuts all the leaves off all the trees around your house. Then you dig up the top two inches in your lawn, removing the grass, pebbles, topsoil, shrubs, flowers and everything. Finally, depending on where you live, the city will either collect your radioactive lawn, or you have to dig a big hole in your yard and bury all the debris there.

The process does reduce radiation levels, but residents complain it doesn’t make the radiation go away. When it rains, the water seems to find nooks that were never washed out. Particles get blown in from other areas. Particles run down hills. They run through gutters. You might wash your house, but get particles from a neighbor upwind.

I kept thinking about how hard it is to keep the dust out of my apartment. I couldn’t imagine what that would be like if I worried the dust would kill me over time. This is the procedure for a single house. Fukushima is trying to clean an entire city.   

A year has passed since the worst nuclear disaster since Chernobyl. The Japanese government hopes to reduce radiation in Fukushima to a level on par with other cities. But some activists say, in the meantime, all children should be evacuated from Fukushima. They’re even educating parents on how to leave. The government hopes to reclaim some parts of the exclusion zone that show low levels of radiation. Residents we spoke to thought that would be difficult, if not impossible. What’s certainly clear, however, is that Japan will be dealing with this for a long time to come. Japan is an organized, wealthy, industrial, disciplined country. It has bullet trains that always seem to run on time. Japan is struggling with a cleanup that may be impossible. Many other countries would probably fare even worse.

Editor's note: Click here to watch Richard Engel's full report, 'The Fallout,' from NBC's Rock Center with Brian Williams.