Nevada Test Site tourists are assured it’s perfectly safe
Sun, May 18, 2008 (2 a.m.)
Sam Morris
Tourists at the Nevada Test Site on April 17 look out over the Sedan Crater, a massive caved-in area left behind by an underground atomic explosion in 1962.
Beyond the Sun
Nearly every month, two tour buses rumble past a ghost town of blown-out houses and concrete bomb shelters, throwing up a cloud of dust.
Sixty-five miles north of Las Vegas, the free tours, booked to capacity months in advance, roll through “the most nuked parcel of ground on Earth,” as lawyer Bob Hager puts it.
Visitors gaze out at the craters made by massive underground atomic explosions, the galleries and trenches where some unsuspecting viewers were exposed to dangerous levels of radiation, the mess halls and dorm rooms where workers whiled away hours between building bombs.
Starting in 1951, 928 nuclear explosions were detonated either above or beneath the desert of the Nevada Test Site.
Sedan Crater, the caved-in wound left behind by a massive 1962 underground test, is one of the two short stops at which Test Site tourists are allowed to escape the climate-controlled confines of their buses. The other is Icecap ground zero, the structure built for a planned explosion that couldn’t be popped off before a 1992 treaty banning testing.
Hager, who has been fighting government efforts to try out non-nuclear bombs at the Test Site, says anyone walking around at the federal property ought to be wearing “full protective gear, including a respirator.”
On the April tour, the visitors wore Disney shirts and fanny packs.
A guide, Robert Keller, a government employee for almost 50 years, 20 of them at the site, told the tourists he wasn’t worried and they need not be either.
“Try not to be afraid of it,” he told his busload. “Try to understand it.”
Despite the yellow and black warning signs posted alongside them, the roads the tour takes through the federal property aren’t “hot” anymore, Nevada Test Site spokesman Kevin Rohrer said. Some of the signs, like the ones at Sedan Crater, are actually historical artifacts. Others mark off areas where underground testing was conducted, areas with a “potential” risk.
Over the past five decades, radioactive dust on much of this 1,375 square miles of land has been worn away by wind and weather, has settled deeper into the ground or has simply decayed, Test Site officials say.
Tourists are perfectly safe during the minutes they spend walking to the lip of a crater or strolling into the ice-cold silo, Rohrer said. Spending 12 hours on a tour bus with 50 other tourists and their tuna sandwiches has its own hazards, but the radiological threats are said to be minimal.
He allowed, however, that there has been the occasional accusation that dust inhaled during a tour has caused illness. Rohrer says there’s no way a modern tour could be to blame.
The dust is where the danger lies, Hager argues, because “there are nuclear particles in that dirt at the Test Site.” Although there are areas that do not pose a health risk, there are also “some very hot spots” and ingesting just one hot speck “can cause cancer,” Hager said.
“If you were to kick up any dirt and you were to inhale one particle, it’s curtains.”
Hager made similar arguments in federal court last year on behalf of Indian tribes and other people who live downwind of the tightly guarded federal property. They opposed the federal government’s plan to explode ammonium nitrate and rocket fuel at the site. They argued such tests would stir up and spread radioactive dust.
That test was canceled, but future non-nuclear weapons tests at the site have not been ruled out.
But Hager is not the only one who says the scars left behind by Nevada’s legacy of atomic testing are deeper than just Yucca Flat’s moonscape, a once crystal-smooth dry lake bed now marred by hundreds of bomb-created pockmarks.
He brought in experts from across the country to testify at hearings in June about the non-nuclear bomb test, called Divine Strake. Although it has been 16 years since nuclear weapons tests were halted, radioactive material still escapes the Test Site on the wind, they said.
The National Nuclear Security Administration and the Test Site, of course, have their own experts, who emphasize that many half-lives, 57 years of them, have passed since the first mushroom cloud of radioactivity billowed above Frenchman Flat. They say the passage of time has rendered the earth there inert — lifeless but harmless.
That’s why, in one of its gestures of openness, the Energy Department, which still performs drastically scaled-back atomic testing on the site, can allow the public to visit the flat.
Manuel Carreon of Las Vegas took the tour for the fourth time in April. He said he remains hale and hearty and “never had any fear.”
One might expect Claudia Stringer of Henderson, on the other hand, to be a bit more suspicious of promises of safety, of every speck of dust blowing in the wind. Her father and uncle both died of cancer after decades as mechanics at the site.
She remembers the day her father, who retired in 1984 and died in 1994, came home from work after getting a dose of radiation. Doctors at the site had made him drink beer, although Stringer said he wasn’t sure why. Turns out it wasn’t just pop science or a home remedy; research has shown that beer reduces radiation-induced changes to chromosomes.
Stringer’s uncle once worked on a vehicle that, after he’d repaired it, was found to be so hot it had to be buried.
Both men began working at the site in 1961 — the same year a short-lived moratorium on testing was observed by the United States and the then-Soviet Union, and a year before the last above-
ground test in Nevada. The pace of testing at the site has waxed and waned over time, with a flurry of aboveground tests in the ’50s and a rush of underground testing just before the ban took effect in 1992.
“Their deaths were caused by radiation,” Stringer said. She said she’s still unsure whether the government knowingly placed her relatives and other Test Site workers in harm’s way.
“I have spent hundreds of hours thinking about it, I really have, because I was so mad when my dad died. That might not be healthy, but it made me mad at the Test Site.
“My dad was a Depression baby and he would go to work no matter what, no matter how bad he felt, because he needed the dollars. And to think they did that to him, it made me really mad.”
The deaths of her father and uncle didn’t persuade her cousin to stop working at the Test Site, though. She does not have cancer.
Asked whether she thinks the tours are safe, Stringer said she’d never thought about it.
“I figured they wouldn’t have tours out there nowadays if it wasn’t safe,” she said.
•••
Tom Enyeart, a radiation protection specialist for the Energy Department, says it’s true that people who live around the Test Site might still be exposed to radiation. Exposure alone is not the issue, however; what counts is the amount of exposure. The radiation that comes off the Test Site is about 0.2 milirem (a measure of radiation) a year, Enyeart said. A move from Las Vegas to St. George, Utah, would give you that same dose, as a result of the elevation change.
“For the history of the human race we’ve been living with natural radiation,” Enyeart said. “Any dose that is a small fraction of what we get from the environment is considered a negligible dose.”
An average person is exposed to about 360 milirem each year. He might increase his yearly dose by 30 to 70 milirem just by taking a few flights from Las Vegas to Reno, or by moving from Las Vegas to, say, Winter Park, Colo., an elevation change of a few thousand feet.
The legal limit for medical professionals and other workers exposed to radiation on their jobs is 5,000 milirem a year. Test Site employees who toiled over radioactive material every day from 1996 to 2005, stewarding the nation’s nuclear arsenal and ensuring our bombs are still deadly, walked away with a yearly dose of only between 30 and 77 milirem of radiation, Enyeart said.
But not everyone believes touring the Test Site is as safe as flying home to see family.
Dr. Diane Stearns, a professor of chemistry who works with uranium at Northern Arizona University and who testified at the Divine Strake hearings, compared visiting, working at or living near the Test Site with a game of chance.
“It becomes a matter of statistics. I wouldn’t feel safe walking around without any protective clothing at a site where there was testing,” she said. “There is radioactive soil. It’s in the air. But it’s a matter of chance. How many people will develop cancer from being exposed? I think there is a risk.”
Stearns reviewed the science the Energy Department was using to prove the safety of the Divine Strake test and found that its pass through the site with a Geiger counter was less than adequate. After the department took soil samples, it found that even in areas where weapons testing had not been performed, such as the area where the Divine Strake test would have taken place, radioactive soil had blown in from original test areas.
Most scientists have to stand up to peer review, but the federal government doesn’t, Stearns said.
“They can use issues of national security. They can hide behind that to do sloppy science,” she said.
Test Site officials say science is their specialty, and their scientific expertise is what enables them to keep all visitors and workers safe.
All Test Site workers who deal with radioactive material wear dosimeters that measure their exposure. Chuck Costa, a former director of testing for Los Alamos National Lab in New Mexico and a Test Site employee from 1962 until January, said in all the years he worked at the Test Site, no employees or members of the public ever got more than the allowed dose of radiation at the site.
Test Site tour guides also wear dosimeters, part of efforts to fend off claims of harm from former tour attendees who allege their ailments relate to an eight-hour drive through the dusty site.
“We’ve had 10 years with no positive hit on a (tour guide’s) dosimeter,” said Rohrer, adding that the majority of workers who carry the devices also score a zero.
Experts on both sides agree on at least this point, however: A dosimeter wouldn’t necessarily measure radiation from airborne particles.
So, as the debate continues, so do the tours.
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