Monday, May 5, 2008

Earthquakes near the Nevada Test Site

Earthquakes near the Nevada Test Site

A magnitude 6.0 earthquake struck in northeastern Nevada today at
about 6:16am local time and was felt as far away as southern Idaho,
Las Vegas, and Southern California, and other locales. The event was
not as disastrous as it could have been due to the fact that the
quake's epicenter was 6.2 miles below the surface. About 300 miles
to the south-southwest of the epicenter, seismograph readings from
the USGS near the Nevada Test Site registered shocks at about 1.0 -
perhaps 2.0 - in magnitude.

Although you won't be hearing this from the Nevada Site Office of the
DOE/NNSA, there is always a danger even with low magnitude
ground-shaking in southern Nevada from regional quakes. On the
grounds of the Nevada Test Site are capped underground testing wells
that are permanent gaseous repositories for the radioactive fumes
from past nuclear tests. There is always the danger of those wells leaking.

That is a main reason why the CEMP network (cemp.dri.edu) of
monitoring stations was put into place - to detect off-site leaks -
although that network is poorly equipped and run (in most cases) by
inexperienced volunteers and contractors with conflicts of
interests. We discuss this topic in details on our site - www.idealist.ws

The other danger is that the NTS is a repository for surface low- to
high-grade nuclear waste especially from the nuclear materials from
past nuclear testing. The radioactive debris from the NTS testing
legacy is contained mostly in the top few centimeters of the soil,
and hundreds of square miles are off-limits due to these dangerous
levels. In 1970, the Atomic Energy Commission (A.E.C.) reported that
the safety tests, aka plutonium dispersal experiments, contaminated
about 250 sq. miles of the 1,350 sq. mile testing grounds. The
radioactivity is still just below on the soil's surface and mostly
NOT cleaned up. Regrettably, the NNSA - in cahoots with the DTRA -
planned to detonate Divine Strake in 2006 (and 2007 before being
stopped by citizen protests) in the NTS's Area 16, which contains
dangerous levels of this 'fallout' in the topsoil.

Divine Strake posed two main threats to downwinders. One risk was
from the soils being ejected up from the explosion; those soils from
the ANFO emplacement hole were inadequately tested for radioactivity
in all (esp. the last) of the DOE's Environmental Assessments. The
other risk was the soils surrounding the test location for Divine
Strake that spanned a few football fields - that entire area was at
risk for radioactivity soil resuspension from the test's
shockwave. The shockwave, from Divine Strake's estimated 3.1-3.4
magnitude explosion, would disturb the top soil layers, and expose
dust from plutonium and other radionuclides to the air currents.

An earthquake in northern Nevada, or anywhere within a few hundred
miles from the NTS, could shake and disturb these toxic soils or
result in well leakage. Slow (or fast) air currents would be able to
carry the contaminated air to downwind communities.

You can view the seismograph readings from today's quake at the
USGS's website; here's a direct link to the map of Nevada:

http://earthquake.usgs.gov/eqcenter/recenteqsus/Maps/US10/32.42.-120.-110.php

Radioactive (gamma only) monitoring around the NTS can be viewed near
real-time at cemp.dri.edu .

This is all not to say that a radiological event at the NTS has
occurred. Rather, it is to say that we all must be vigilant in
watching for radiation leakages for ourselves and communicate our
findings to the public because, as we all should know, the DOE won't
do that for us.

-Andrew Kishner
www.idealist.ws

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