[ RadSafe ] Feds puzzled by gamma radiation higher than normal near wildfire

[Michael McNaughton]

Following the Cerro-Grande fire at Los Alamos, I and my colleagues 
investigated the increased airborne radiation measured during the fire. 
Almost all the increased radioactivity we detected is from the long-lived 
radon decay product, lead-210, and its progeny: bismuth-210 and 
polonium-210. However, I am puzzled by the word "gamma" that appears 
several times in the article below. Pb-210, Bi-210, and Po-210 emit few 
gammas, mostly of low energy. Does anyone on this list have more information?

mike

At 01:35 PM 07/13/2007, Sandy Perle wrote:
>Feds puzzled by gamma radiation higher than normal near wildfire
>
>The Salt Lake Tribune, Jul 13 -  A puzzle has sprung from the flames
>of the Milford Flat Fire: What's pumping radiation into the air? The
>National Nuclear Security Administration said Thursday its radiation
>monitors in the area are showing gamma radiation spikes seven times
>higher than the normal background. But before anyone runs to the
>doctor, it's worth pointing out that even those spikes, if someone
>breathed them for seven hours straight, produce less than one-2,000th
>of the radiation dose a Utahn normally gets in a year. "You're
>talking about a very small dose," said NNSA spokesman Darwin Morgan.
>The agency, which had proposed a massive, non-nuclear explosion
>experiment at the Nevada Test Site last year, monitors the air for
>radiation at 29 monitoring stations in Utah, California and Nevada.
>The agency canceled the so-called Divine Strake test after hearing
>from thousands of Utahns who complained that the explosion would send
>radiation-tainted debris into their air and onto their landscape. "We
>heard loud and clear from the people of Utah they are concerned about
>radiation," said Morgan, explaining his agency's reasons for
>publicizing the radiation-meter findings. Morgan said filters from
>the Milford monitoring station are being analyzed at a laboratory.
>The agency thinks that naturally occurring radon is being released
>from the ground, but only study of the material captured on the air
>filters will tell them for sure. Dane Finerfrock, director of the
>Utah Division of Radiation Control, said the fact that radiation is
>released during combustion is no secret. "There's a radioactivity in
>that forest and brush," he said, "and some of it stays in the ash and
>some of it goes into the atmosphere." Morgan said there is no data
>about the radiation from the Neola North Fire in eastern Utah. The
>agency does not have monitors in that part of the state.
>----------------------

Mike McNaughton
Los Alamos National Lab.
email: mcnaught at LANL.gov or mcnaughton at LANL.gov
phone: 505-667-6130; page: 505-664-7733