When reactor #4 exploded at the Chernobyl nuclear power plant in the Ukraine on April 26, 1986, it became the most terrible nuclear accident that the world had ever known. But it was days before people knew exactly what had happened.
CHERNOBYL SETS OFF DETECTORS IN SWEDEN
"I didn't discover it. I just happened to be there," Cliff Robinson tells Radio Sweden at his home in Uppsala.
Before the world found out that a huge accident had happened at Chernobyl, Robinson knew something was wrong. He was working as a chemist at Forsmark, a nuclear power plant a couple hours north of Stockholm.
It was early Monday morning on April 28, 1986, and he had just eaten breakfast in the coffee room at the plant. He'd gone to the washroom, on the border of the controlled and uncontrolled areas of the plant, to brush his teeth. On the way back to the locker room, he had to pass through a radiation detector.
Robinson set the alarm off.
"It was so strange, because I hadn't even been in the controlled area!" he says.
He went through a couple more times, and the third time, the alarm didn't go off. He and one of the workers who monitored the detector thought it was a mistake and that the detector simply need some adjustment.
Robinson went about his duties, monitoring radioactivity within the power station. When he got back, he recalls, there was a long line of workers waiting at the detector. No one could get through, he says, because the alarm kept going off.
Robinson borrowed a shoe from one of the people there and took it into the lab, where he put it on a germanium detector.
"Then, I saw a sight that I will never forget," he says. "The shoe was highly contaminated. I could see this spectrum rising up very quickly. And it was just amazing, because there were many radioactive elements there that we normally didn't see in the cooling water at Forsmark."
"I remember vaguely that I had some idea that perhaps a nuclear bomb had been exploded somewhere," says Robinson.
Robinson called his boss, who at this point, knew that something was up. The boss asked him to double-check the plant's chimneys to see if it was possible that Forsmark had released the radiation.
Suddenly, Robinson heard another alarm: this one was for workers to evacuate the plant.
Robinson stayed behind, though, to analyze the samples. "Nothing indicated any malfunction or problem at Forsmark. It was just that the surroundings were very heavily contaminated," he says, adding, "I remember I was very stressed and whatever I was doing it felt like it was going very slow."
USSR ADMITS TO ACCIDENT
Leif Moberg worked at the Swedish Radiation Safety Authority at the time – in fact he still does – dealing with nuclear research projects. He remembers when the Authority got the call from Forsmark that Monday morning.
At first, the Authority thought it could be possible that the radiation was coming from Forsmark, but Moberg says that within a couple of hours, it became clear that Forsmark wasn't the culprit.
One initial thought was that the radiation could have come from a nuclear bomb. But chemical anaylsis ruled out this possibility.
The Authority received reports of high radioactivty from other plants as well, and so, they charted the course of the wind and saw that it had originated in the Southeast. Chernobyl was one of the points they plotted on the map.
So, how did the situation move from Sweden realizing that something had gone seriously awry to the world finding out?
That day, Swedish diplomats were in touch with Moscow inquiring about whether there could have been a nuclear accident there. But the answer they got was "no". Sweden warned that they were going to file an official alert with the International Atomic Energy Authority, and it was only then that the Soviet Union admitted that there'd been an accident at Chernobyl.
Moberg says that's when his Authority got nervous, because they didn't know the extent of the contamination yet.
RADIOACTIVITY AFFECTED SWEDEN
The radioactive cloud from Chernobyl rode the wind over Sweden like an invisible dragon. The dragon didn't breathe fire. Instead it spit out rain. As raindrops landed, so did radiation, especially in parts of north and central Sweden, for example, the areas around Uppsala and Gävle, along with Västerbotten and others.
Keeping food from getting contaminated was an issue in some places.
Northern Sweden absorbed a whole 5% of the radioactive cesium-137 that Chernobyl released into the air. Like other forms of radiation, this Cesium-137 can increase the risk of getting cancer.
Atoms of it wound up in the lichen that reindeer graze on. And that year, after the slaughter, almost 80 percent of the Swedish reindeer meat was too contaminated for sale.
Reindeer farmers had to change their practices, slaughtering earlier in the year before the animals had a chance to eat the moss.
The Swedish authorities raised the limit for permissible radiation in game, freshwater fish, wild berries and mushrooms, based on their view that these foods made up only a little bit of the Swedish diet. But even to this day, a small portion of reindeer can't be sold because they have too much of the radioactive element.
After 25 years, what's left of Chernobyl in the food and in people's bodies? Leif Moberg from the Swedish Radiation Safety Agency, says that the vast majority of radioactive chemicals have spent out their half lives. But not Cesium 137. That's the one that had caused problems for reindeer herders. Its half life is 30 years, which means that about half of it is still here.
But he says a lot of it is fixed in clay, which means it's not available for plants to take it up. Certain mushrooms can still have higher contents of the radioactive particle, but he says people don't have to worry unless they have a diet heavy on specific mushrooms, reindeer, game and lake fish.
Moberg says that Chernobyl has had no noticeable impact on cancer rates or the death rate here in Sweden.
In the end, it's hard to tell exactly how big Chernobyl's impact really was on Sweden.
In terms of policy, it wasn't much. The partial meltdown at the Three Mile Island nuclear power plant in the U.S. a few years before Chernobyl had already prompted Swedes to vote for phasing out atomic energy. But the government reversed this decision last year and will allow new plants to be built as the existing ones get older. Sweden has 10 nuclear reactors and they supply the nation with a little less than half of the nation's energy.
But Chernobyl did kindle discussions about how to get plant workers to embrace a culture of safety.
As one museum here in Sweden prepares to bury the memories that Sweds have of Chernobyl, how long will it really be though before the dust of Chernobyl is really cleaned away, both literally and metaphorically?
Cliff Robinson, the scientist who set off alarm bells at Forsmark 25 years ago, says the event doesn't haunt him per se, but every now and then, it still goes through his mind.
"When I hear news from Japan like today, then it makes me really think about it," he says.