Imagine sweeping your kitchen floor and then having to throw away not only the dirt you've swept up but also the broom, the dustpan and even the trashcan you threw everything into. That scenario gives you a glimpse of the difficulty and expense of cleaning up radioactivity; workers have to address the source of the radiation and everything that source has contaminated. Yet as difficult as the process can be, it's not always complicated. In many cases, workers are tasked with simple chores like sweeping up low-level radioactive material, wiping down surfaces with decontaminating chemicals and collecting debris for disposal.
Much of the challenge comes from the fact that radioactive material can spread to the environment in several ways -- particularly when things go wrong -- making cleanup exponentially more difficult. For instance, radioactive particles can seep into groundwater, flow into nearby lakes, rivers and oceans, float through the atmosphere and even contaminate livestock and crops. Each type of environmental contamination requires a different response.
When radioactive material contaminates groundwater, organizations like the U.S. Environmental Protection Agency (EPA) oversee the construction of groundwater extraction and treatment facilities. If the soil itself is contaminated, on the other hand, it may need to be extracted and buried at a containment facility or even encased in concrete. When radioactive material spreads into large bodies of water or into the atmosphere, decontamination can be impossible. In such cases, fish, livestock and produce are closely monitored for increased levels of radioactivity.
Regardless of the type of contamination, mopping up radioactive materials is a dangerous task, and patience is sometimes the best approach to safely decontaminating a site. All radioactive material decays over time, eventually breaking down into stable -- and safe -- daughter elements. And while this process takes thousands of years for high-level radioactive waste, it occurs much more quickly for low-level waste like safety equipment and water used inside of a nuclear power plant. Accordingly, waste is often stored at the site where it was generated for years or even decades before it's properly disposed of.
Because the process of cleaning up radioactive material is so dangerous, it's highly regulated around the world. In the United States, federal agencies like the EPA, the Department of Energy and the Nuclear Regulatory Committee set safety guidelines, issue licenses to operate nuclear power plants and oversee any cleanup efforts.