Fallout particle offers insight into Fukushima nuclear accident

Researchers used high-powered imaging technology to produce a 3D image of a particle contaminated by uranium from a Fukushima reactor. Photo by University of Bristol/Diamond Light Source

June 26 (UPI) — Researchers have found and studied a fallout particle containing uranium released by the Fukushima nuclear accident. The study offered scientists insights into the sequence of events that led to the Fukushima meltdown.

Researchers successfully isolated a sub-millimeter particle from an environmental sample collected near the Fukushima Daiichi Nuclear Power Plant. Using the powerful light beam at the Diamond Light Source in the United Kingdom, researchers performed high-resolution combined X-ray tomography and X-ray fluorescence mapping. The high-powered imaging technology revealed the presence of uranium trapped around the outside of the highly porous particle.

The so-called microfocus spectroscopy beam at the Diamond Light Source allowed scientists to observe the physical and chemical properties of the uranium incursions. By analyzing the spectral signature that bounced back when targeting incursions with the highly-focused X-ray beam, scientists were able to confirm that the uranium came from Fukushima’s reactor Unit 1.

Though the uranium came from Fukushima’s nuclear reactors, scientists determined that the uranium exists in an environmentally stable state. Its stability has been enhanced by an insulating layer of silicate material.

“While unlikely to represent an environmental or health hazard, such assertions would likely change should break-up of the Si-containing bulk particle occur,” scientists wrote in their paper. “However, more important to the long-term decommissioning of the reactors at the FDNPP … is the knowledge that core integrity of reactor Unit 1 was compromised with nuclear material existing outside of the reactors primary containment.”

Researchers suggest the findings — published this week in the journal Nature Communications — can help them understand the series of events that led to the meltdown at reactor Unit 1.

“I am very pleased that this research has been recognized in Nature Communications. It is a tribute to the excellent collaboration of our partners at JAEA and Diamond Light Source,” Peter Martin, physicist at the University of Bristol, said in a news release. “We have learned an invaluable amount about the long-term environmental effects of the Fukushima accident from this single particle as well as develop unique analytical techniques to further research into nuclear decommissioning.”

https://www.upi.com/Science_News/2019/06/26/Fallout-particle-offers-insight-into-Fukushima-nuclear-accident/1471561558100/