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When the wind was blowing at night - the perfect
time to test the worst-case scenario - the Air Force conducted what
amounted to eight intentional meltdowns of small nuclear reactors in
the Utah desert in 1959.
Resulting radiation clouds were tracked by sensors placed up to 20
miles downwind and across a 210-square-mile area at Dugway Proving
Ground, according to documents obtained through a Freedom of
Information Act request.
But the clouds traveled beyond that. When last detected, they were
spreading toward U.S. 40 (now Interstate 80), the major highway
between Utah and northern California. The communities of Wendover and
Knolls may have been in the paths of some clouds.
The total amount of radiation released by the tests was 14 times more
than the infamous Three Mile Island reactor accident, a near-meltdown.
But it was more than a million times less than the huge Chernobyl
reactor plant meltdown in the Ukraine.
"It is large enough to be significant, but it's not the worst thing
they've ever done. The atmospheric testing (of nuclear bombs) was much
worse," said Daniel Hirsch, former director of a nuclear policy
institute at the University of California-Santa Cruz.
His opinion is typical of many scientists interviewed, who say tests
used radiation amounts that were probably larger than necessary, may
have been useless because they were for a useless program and may have
unwittingly endangered Utahns.
Hirsch, for example, says the tests might have caused an extra "tens
to hundreds" of cases of cancer downwind.But some scientists say the
tests posed virtually no public danger because they were remote and
used relatively small quantities of radioactive materials that were
spread thin.
Activists are upset that yet more secret tests at Dugway are
involuntarily emerging. Thousands of other secret radiological,
chemical and germ warfare ex-per-iments have been revealed there in
recent years.
"It makes you wonder what all did happen out there," said Downwinders
President Preston J. Truman.
The beginning
Documents say the tests were ordered because the Air Force and the
Atomic Energy Commission were trying to develop nuclear-powered
aircraft - and decided they should assess the hazards of a
runaway-reaction meltdown in an airplane reactor.
Critics - such as retired biochemist H. Peter Metzger, who has studied
the program - say the military had long known that such airplanes
would need so much shielding to protect crews from radiation that they
would be too heavy to fly.
They would also emit radioactive exhaust. But Congress kept the
program alive anyway. "The program was stupid, so the tests were
stupid," Metzger said.
But to continue research and simulate a meltdown, the Air Force
decided to burn portions of reactor fuel in high-temperature furnaces.
Forced air would blow the resulting radiation to the winds. Radiation
clouds would be tracked downwind and deposits measured.
The first series of tests occurred in 1958 near Arco, Idaho - but were
tracked only 5 miles downwind. In 1959, larger tests were moved to the
Army's Dugway base because it was big enough to allow measuring clouds
for 20 miles downwind without coming near civilization.
The main test area was a roadless, barren salt flat described as
having only sparse pickleweed growing.
The Air Force said it wanted the tests to show how meltdown radiation
disperse, how much of the radioactive fuel would be released to the
atmosphere, how large particles would be and what biological and
ecological effects would occur.
The Dugway tests
At midnight on Aug. 5, 1959, the first test occurred under clear skies
with a temperature of 75 degrees and the wind blowing an average 24
miles an hour toward the north-northwest.
It and seven more tests that followed were conducted only at night
when a steady wind was blowing - because radiation could travel
farthest under those conditions. Documents said that was needed "to
obtain data required to establish the upper limits of the possible
hazards of a nuclear accident of the meltdown type."
The furnace was placed on a pad near Granite Mountain. Inside was
material that had been freshly irradiated at a reactor in Idaho. It
was then placed inside the lead-shielded furnace and shipped to
Dug-way. After the test, the furnace and leftover reactor fuel would
be returned to Idaho for burial.
The fuel had been irradiated in such a way as "to provide an inventory
of the biologically hazardous isotopes that are found in abundance in
an operational aircraft," documents said.
Experimenters were most interested in 11 such isotopes (radioactive
forms of elements), ranging from strontium-90 to cesium-137,
iodine-131 and barium-140.
The furnace was ignited, and radioactive iodine-131 began spreading
away almost immediately. After 15 minutes, the reactor fuel was molten
- and was kept that way for another 13 minutes as parts of all the
other isotopes vaporized.
About 450 sampling stations that were spread up to 20 miles downwind
across a fan-shaped area (see map on B1) measured how much radiation
was dropping where, how big particles were and what directions they
spread. Some dogs and rats were also exposed for study.
The same procedure was followed at the same place and under similar
conditions for other tests on Aug. 10; Sept. 8, 12, 18 and 30; and
Oct. 24 and 25.
Three other tests also occurred but reportedly released no radiation
to the atmosphere. All the furnace exhaust from them was captured for
measurement and filtered before release.
The Air Force was able to figure out averages for how much of
different isotopes would vaporize in a meltdown with the results.
It figured, for example, that 19 percent of iodine-131 would escape.
The source fuel cells used in the tests originally had a total of
126.1 curies of iodine-131. The 19 percent it figured was released
totalled 23.96 curies - or about 60 percent more iodine radiation than
released by Three Mile Island. The release fraction for other isotopes
was as small as 2 percent. The tests had started with 2,412.04 curies
of the 11 isotopes the Air Force studied.
Based on what the Air Force figured to be average release fractions,
the Deseret News calculated that 215.57 curies of total radiation were
released.
Other findings included that the vast majority of particles released
were smaller than 10 microns - meaning released gases were considered
an aerosol, which could travel much farther than if it consisted of
heavy particles.
In one test, jet fuel was also burned near the furnace - as would
happen in an airplane crash. The Air Force found that about half of
the released radioactive iodine attached itself to the smoke and
spread with it.
It also found that maximum concentrations of radiation remained within
8 feet of the ground as the cloud traveled.
University of Utah teams also dug up 6-inch soil samples three months
after the tests and found 90 percent of the deposited radioactivity
remained in the top 2 inches.
No results on how test animals fared was ever released. An Energy
Department history says the University of Rochester, which was in
charge of biological portions of the tests, reported problems with the
data collected that prevented their use.
Also, tests found that the further from the furnace, the less
radiation was deposited. The cloud also tended to widen with distance
and in some tests was possibly headed toward Wendover (about 50 miles
away) or Knolls (40 miles away), and definitely toward the US-40
highway.
How dangerous?
Scientists disagree how dangerous the test were to the public. Some
say virtually no risk resulted, while others say it may have been
significant.
Dr. Richard Wilson, a Harvard physics professor who specializes in
nuclear reactor safety, believes little or no risk occurred - nor
would any persist today.
"I doubt they violated any standards at the time," he said. "In the
early days, nuclear power plants released about that much in a year -
although they no longer do. They didn't cause any real trouble."
He added about lingering isotopes from the tests in the desert, "You
likely won't detect any of them now anywhere. . . . They would have
been swamped by (radiation from) Chinese atmospheric testing."
Metzger, the retired chemist/nuclear energy historian - who is often
critical of similar testing, also said, "These are all very small
numbers. You couldn't do testing with that much today because of all
the laws . . . but it's nothing to get too excited about."
But Hirsch, from UC-Santa Cruz, said, "For me to consider this
insignificant, the amounts would have had to be in the level of
millicuries - or thousandths of curies. But it is in the level of
curies and hundreds of curies."
He said, "They could have done the same thing with much smaller
amounts or even used surrogate materials that are less dangerous." At
least, he said, releases were much smaller than if the Air Force had
actually melted down an entire airplane reactor instead of just a
portion of a fuel cell.
Roland Finston, a retired health physicist from Stanford University,
added, "It's not a trivial release. But because of where it was, it
was probably of minor consequence acutely (in the short term)."
Finston noted that the source amounts of radiation used before release
in Utah were only a millionth of what modern power-plant reactors use.
He also said they were about a thousandth of the amount used in the
atomic bomb on Hiroshima.
Over the long term, he said some material could cause problems
depending on how much entered the food chain but guessed, "The area
now might be a little `hotter' than other areas, but because of world
nuclear fallout I would guess it's not by much."
Dr. Karl Z. Morgan, who was director of health physics at Oak Ridge
National Laboratory, said he was also concerned about some
long-persistent isotopes used in the test that could get into the
desert food chain.
"Strontium-90 has a half-life of about 30 years, meaning that 30 years
or so later now, half of it would still be around," he said. But only
small amounts (about a half curie) were released and scattered over a
large area.
Hirsch said even small doses of strontium-90 and iodine-131 can cause
big problems.
"Strontium is a `bone-seeker.' Because of its chemistry, it mimics
calcium and can replace it in bones. If it is ingested, it can
concentrate in the bones and cause cancer.
"Strontium stays around and can continue to be resuspended in dust. It
can remain toxic for 600 years and is very potent. So it's not only
what happened the day of the test but also the danger that persists,"
he said.
Also, he said iodine-131 concentrates in the thyroid gland, "so quite
small doses can cause big problems" - and can be problematic if cows
eat grass contaminated with it and children drink the milk.
Hirsch said his off-the-top-of-his head guess - based on the amount of
radiation released and the potential downwind population - is "that
the amounts are sufficient for some tens or hundreds of cases of
cancer" through the years.
Even if scientists say amounts were relatively small, Truman with the
activist group Downwinders said, "That's not the point. They shouldn't
be releasing that kind of stuff. Anytime you release this stuff around
where people may be, it's dangerous.
"If you're looking at developing a model on how this stuff will act,
you don't need to use 215 curies - you could use a lot less."
What now?
Truman said he plans to ask a state advisory committee on radiation to
further explore what happened with the tests and why the state
apparently never heard about them.
"My biggest concern is that you had to dig to find this out instead of
them telling the state about it - especially when the state asked
Dugway for all documents about radiation testing," Truman said.
"It's another example of how careless agencies have been in the past
and how important it is to keep a close eye on everything in the
future."
The disclosure also comes as President Clinton has created the
Presidential Advisory Committee on Human Radiation Experiments to
explore such tests during the Cold War.
A staffer at that committee noticed a mention of the tests and tipped
the Deseret News about them - which used the Freedom of Information
Act to obtain detailed documents about them.
The panel is expected to review the tests as part of its work. But
that group has focused more on medical tests that intentionally
targeted people, rather than weapons tests that may have affected
people without specifically targeting them.
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Additional Information
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