When We Are History

Steve McCracken has overseen a 13-year, $800 million cleanup and burial of the radioactive waste at Weldon Spring. Now that the odyssey is nearing its end, one thought haunts him -- how to warn people in the future not to dig it up.

These materials are radioactive in that their atoms hold surplus energy that they're constantly trying to get rid of. An atom spins off its excess energy until it finally becomes normal, or "stable," and the discarded, high-speed energy is the radiation.

If you had a little time on your hands and could sit and watch an atom of, say, uranium-238 decay from its unstable, highly radioactive state all the way down to its stable state, you would see the atom change from one substance to another every time it shed some of its energy. That's because when an atom sheds part of itself, its structure changes, so what started out as uranium-238 turns into thorium-234. This thorium-234 also tries to dump extra energy and in doing so turns into protactinium-234. The process continues until there's no more energy to get rid of and the final material is stable. It's called "radioactive disintegration," and in the case of uranium-238, which decomposes 15 times before stabilizing as lead-206, it takes about 4.5 billion years.

Meanwhile, the radiation is being released at very high speeds in one of three forms: gamma rays, beta particles and alpha particles. If you held up a stack of Kleenex, gamma rays would move through it like a bullet through fog. Beta particles would move through about 2 centimeters of the stack, and alpha particles -- the stuff floating around in the waste pits at Weldon Spring -- would only travel through about 1 or 2 micrometers. A layer of dead skin cells on a person's body would be thick enough to deflect them.

Ingested into the human body, however, alpha radiation causes major chromosomal damage. So long as the sludge was underwater in the pits and not flying around in the air or prowling through somebody's lunch, there was no immediate danger.

But around the pits, piled in tangled webs of contaminated concrete and steel debris that wasn't underwater, were the 4,000 barrels full of contaminants like asbestos, PCB-laced oils, trichloroethylene and uranium wastes. The overgrown fields surrounding the pits were also strewn with canisters, crates, tanks and drums, swelling and sweating their unknown toxins.

The other major problem at this part of the site was the 44 buildings to the east of the waste pits. And 20 years of neglect had worsened the danger. "Really all they did was put a guard at the gate, so the buildings and structures deteriorated very quickly because they weren't maintained," McCracken says. "So over that 20 years, these buildings started falling apart, and because air and water was able to contact these waste materials, they began migrating off-site."

The more immediate threat, however, was posed by the quarry. Sitting like a giant septic tank a few miles south of the chemical-plant area, the limestone quarry was first used by the Army back in the '40s as a humongous trash can for rubble contaminated with TNT. When the AEC came in a decade later, it piled uranium and radium contaminated equipment and soil right on top. And over the next 20 years, while the guards stood at the gate, groundwater seeped out through the porous limestone floor of the quarry. By the time McCracken and his team tackled the quarry in the mid-'80s, it contained a toxic stew: about 120,000 cubic yards of contaminated metal, concrete, rock, soil and building material was floating in 3 million gallons of equally contaminated water.

McCracken and his team were looking at poisons that were leaching, leaking and blowing off-site at rates no one could definitely pin down. And the seriousness of the public-health danger was yet unknown.

The most immediate concern was the contaminated water in the quarry. It wasn't just sitting there like tepid water in a ceramic bowl. It was leaking through the fractured limestone and heading toward the county well fields, a quarter-mile away, that supplied water to 60,000 people living in St. Charles County.

In addition, a 1.5-mile natural channel from the chemical-plant site down to the Missouri River became the conduit for no-one-knows how much radioactive material that washed down from the exposed debris around the pits, in the fields and in the buildings. Moreover, the waste pits weren't lined with any protective material, so toxins from the sludge began seeping into the groundwater beneath the pits.

At least three lakes in the surrounding August A. Busch Memorial Wildlife Area were contaminated with uranium, and down by the quarry, contaminants were leaking into the Femme Osage Slough.

To compound the problem, just half-mile north of the site, in the path of prevailing winds, sat Francis Howell High School, attended by 2,500 students each day.

The job was huge, it was complex and -- worst of all, from McCracken's point of view, anyway -- it was scaring the hell out of the people all around.

Communication Breakdown
It was like mobilizing for the invasion of a small country. Decisions had to be made on how to pick up and store materials that would be radioactive for the next 4.5 billion years. Task forces were set up. Environmental reports were issued. Cost estimates were sent to Washington, D.C. The Missouri Department of Natural Resources and the United States Geological Survey began groundwater testing, and the DOE sampled fish in nearby lakes, soil in surrounding fields and air around the high school.

« Previous Page
Next Page »