[ SCIENCE ] Radiation from Fukushima: an interview with Dr. Ken Buesseler (Part 2)
You can read the first part of Dr. Buesseler’s interview right here!
Dr. Buesseler is a Senior Scientist at Woods Hole Oceanographic Institution in Woods Hole, Massachusetts. His research interests include studies on the fallout from atmospheric nuclear weapons testing, assessments of Chernobyl impacts on the Black Sea, and the examination of radionuclide contaminants in the Pacific resulting from the Fukushima nuclear power plants. He is leading the Radiation from Fukushima segment of research for The Longest Swim.
When a tsunami flooded Japan’s Fukushima Dai-ichi Nuclear Power Plant in 2011 it initiated the largest accidental release of radioactive contaminants into the ocean in history. Scientists estimate that the majority of these contaminants moved offshore, where ocean currents diluted and transported them westward from Japan to North America. During his swim Ben will follow a similar track as these currents; using both a wearable “RadBand” cesium collector and conventional water sampling, The Longest Swim crew can provide a look at how far and how fast these particles are moving, as well as their concentration across the Pacific Ocean.
What kind of research will you be doing with The Longest Swim?
We’ve been looking at Fukushima Dai-ichi and the radioactivity released to the coast off Japan since 2011, right after this horrible disaster started. As we think about those types of events, they release contaminants into the ocean. In this case, radioactive forms of cesium are what we track coming from a particular site. The questions we ask as oceanographers are: where does it go, how fast does it get there, and what are the transport pathways? That involves ocean currents and mixing. So what we’re excited about with The Longest Swim is that the track that’s being followed will take advantage of those same currents going from Tokyo across to San Francisco, which would be the same path that the radioactive cesium is taking.
When you talk about this contamination in the ocean, can you measure it with a Geiger counter? Isn’t the detection procedure much more complex?
Yes. Even when we went to Japan in 2011 we carried thousands of kilos of water back home with us. We actually used Geiger counters on the ship to make sure we weren’t in harm’s way, but we put those as close as possible to the samples and still couldn’t detect anything. Once cesium gets in the water the concentration immediately decreases because of mixing. That’s completely different than on land when it falls on soil and sticks in the first couple centimeters of clay material. It doesn’t go anywhere. So on the ocean side, when you get within one kilometer, the radioactivity levels are lower than in New England where we have all these granite rocks that release natural radon and other gases that are radioactive. The ocean actually has a lower background radiation and nothing you can detect on a Geiger counter in terms of the cesium contaminants. But they’re there and we shouldn’t be dismissive of concerns about them.