The race against radon

By | May 13, 2022

Chris Baraniuk writes:

Deep in the frozen ground of the north, a radioactive hazard has lain trapped for millennia. But UK scientist Paul Glover realized some years back that it wouldn’t always be that way: One day it might get out.

Glover had attended a conference where a speaker described the low permeability of permafrost — ground that remains frozen for at least two years or, in some cases, thousands. It is an icy shield, a thick blanket that locks contaminants, microbes and molecules below foot — and that includes the cancer-causing radioactive gas radon.

“It immediately occurred to me that, well, if there is radon underground, it will be trapped there by a layer of permafrost,” recalls Glover, a petrophysicist at the University of Leeds in England. “What happens if that layer suddenly isn’t there anymore?” Ever since then, Glover has worked on methods to estimate how much radon — which is released as the element radium decays — might be liberated as climate change causes the permafrost to thaw.

Significant areas of Arctic and sub-Arctic ground contain permafrost — but today it is melting, and the rate of that thaw is accelerating. In a report published in January, Glover and coauthor Martin Blouin, now technical director at the mapping software firm Geostack, used modeling techniques to show that homes with basements built on areas of permafrost could be exposed to high levels of radon gas in the future. “As the permafrost melts, this reservoir of active radon can flood to the surface and get into buildings — and by being in buildings, cause a health hazard,” Glover says. [Continue reading…]