[ RadSafe ] Tumbleweeds and other vectors

[S L Gawarecki]

This is an "interesting" tale.  I didn't know about the bunnies at
Hanford.  No mention of Oak Ridge's hot frogs, though.

http://gizmodo.com/how-tumbleweeds-spread-radiation-from-old-nuclear-sites-1508617887

How Tumbleweeds Spread Radiation From Old Nuclear Sites

The tumbleweed, which seems so at home rolling down an American highway, is
actually an invasive plant from the Russian steppes. In the relatively
short time it's been invading the plains--just over a century--the tumbleweed
has managed to establish itself as an indelible symbol of the western
landscape. It is the ultimate sleeper cell, we might say, an enemy plant,
if we were to resort to Cold War metaphors.

For last month's issue of *National Geographic*, George Johnson wrote an
eloquent hate letter<http://ngm.nationalgeographic.com/2013/12/tumbleweeds/johnson-text>to
the tumbleweed. Johnson has been fighting a losing battle against the
tumbleweed on his patch of New Mexico land; the plant is ubiquitous and
tenacious, making it a ready invader.

What especially caught our attention, however, was this paragraph, which
shows just how persistent the damn weed is. A note on terminology here:
"tumbleweed" can refer to any number of plants that break free of their
roots and tumble around spreading their seeds, but the most common one is
the Russian thistle, also known by its scientific name *Salsola tragus.*

*During the early 1960s, after aboveground nuclear testing finally ceased
at the Nevada Test Site, the first thing said to grow back was Russian
thistle. **Radioactive Salsola has come tumbling out of the old Hanford
Nuclear Reservation in Washington**, where plutonium was manufactured
during the Cold War. I half expect to hear someday that Russian thistle has
been found on the moon.*

The Hanford site in Washington state, which is the most contaminated
nuclear site in the U.S., has recently encountered trouble with leaking
waste tanks<http://www.huffingtonpost.com/2013/06/21/hanford-nuclear-site-tank_n_3479387.html>.
What intrigues me is that the containment problems at Hanford have also
long been compounded by what one internal
presentation<http://www.hanford.gov/files.cfm/Attachment_3_Bio_Cont_Pro_Update.pdf>calls
"biological vectors," aka tumbleweeds but also fruit flies, mud
dauber wasps, pigeons, swallows, mice, and rabbits, species on the loose
potentially spreading radiation beyond the site. Hanford even has a whole
Biological Control program to deal with these vectors.

In 1959, in what may be the worst pest incident in Hanford history, a
badger broke into a radioactive waste pit setting off a biological chain
reaction. Bunnies tromped in looking for salt, spreading 200 curies worth
of radioactive poop over 2,000 acres of the Hanford site, according to
*Science* <http://www.sciencemag.org/content/236/4809/1616.extract>*.
*The appearance
of radioactive doo
doo<http://online.wsj.com/news/articles/SB20001424052748704694004576019280235026892>today
would launch a whole manhunt--or rabbithunt--for the offending rodent.
After all, we can't have radioactive bunnies dropping cesium-filled pellets
all over the landscape. A former nuclear reactor still needs pest control.

Nuclear's long-lasting legacy, whether for electricity or for war, forces
us to act as permanent stewards of the earth. Hanford has been a massive
cleanup site for decades, and its tanks will need monitoring for many more
to come. When Yucca Mountain was being proposed as a nuclear waste
repository<http://bldgblog.blogspot.com/2009/11/million-years-of-isolation-interview.html>,
the EPA mandated warnings that could be intelligible for 10,000 years to
come<http://sarahzhang.kinja.com/preview/In%201959,%20in%20what%20may%20be%20the%20worst%20pest%20incident%20in%20Hanford%20history,%20a%20badger%20broke%20into%20a%20radioactive%20waste%20pit.%20Bunnies%20then%20tromped%20in%20looking%20for%20salt,%20spreading%20200%20curies%20of%20radioactive%20poop%20over%202000%20acres%20of%20the%20Hanford%20site,%20according%20to%20Science.>.
That's a blink in geologic time--but how many 10,000 year-old, or even 1,000
year-old, languages are readily understandable to us now?

But anyway: tumbleweeds. The plant's taproots can creep 20 feet
down,<http://articles.latimes.com/2001/apr/15/local/me-51273>bringing
up radioactive waste from underground burial sites. Then winds can
carry these radioactive bundles up to four miles away. A few years ago,
Hanford's staff was removing 30 of them a
year<http://online.wsj.com/news/articles/SB20001424052748704694004576019280235026892>.
"Our dream is that we have this place tumbleweed-free," the site's then
biological control manager for radiation protection told the *L.A.
Times*<http://articles.latimes.com/2001/apr/15/local/me-51273>in 2001.
"But that's about as likely as a Soviet reunion," quipped the
paper in response.

As the most visible of radioactive "biological vectors" at Hanford,
tumbleweeds seem to have especially captured the imagination. The idea of
radioactive waste tumbling about is radically at odds with, say, a gif of
tumbleweeds meant to convey, "Nothing here, move along." But there's plenty
to ponder here--most of all how a radioactive danger of our own doing ended
up being spread by Russian invaders. [*National
Geographic*<http://ngm.nationalgeographic.com/2013/12/tumbleweeds/johnson-text>
*--**Science* <http://www.sciencemag.org/content/236/4809/1616.extract>*--**Wall
Street Journal*<http://online.wsj.com/news/articles/SB20001424052748704694004576019280235026892>
*--**L.A. Times* <http://articles.latimes.com/2001/apr/15/local/me-51273> |
Thanks to Matt Mirandi <https://twitter.com/MattMirandi> for the tip]


Regards,
*Susan Gawarecki*

ph: 865-494-0102
cell:  865-604-3724
SLGawarecki at gmail.com