After the nuclear meltdown of the reactors at Japan’s Fukushima Daiichi nuclear power plant in 2011, scientists from around the globe have begun a renewed study into the effects of radioactive material interacting with the surrounding soil and water; this includes examining existing waste containment facilities.
Considering that most of the waste produced from nuclear power in America is stored at only a few locations, including the Hanford site in Washington and the Savannah River site in South Carolina. Both sites currently house nuclear waste, some of which has been stored since the 1950s with no immediate plans to properly dispose of the waste.
Radionuclides that are a major by-product of nuclear fission, and are causes for immediate concern include radioiodine and plutonium isotopes. The half-life, or the time it takes for half a given radioactive sample to decay, can range from 14.4 years for plutonium to 16 million years for radioiodine. These radionuclides, along with other radioactive material can seep through protective barriers and leach into groundwater. The contaminated groundwater can transport the radioactive isotopes into the surrounding land or waterways where bioaccumulation can take place.
Scientists from Texas A&M University at Galveston, along with other universities from across the United States and Japan have teamed up to find out what happens to radioactive material once it leaves a nuclear waste facility.
“Anytime you use energy, it causes pollution and accidents,” Dr. Peter Santschi, lead scientist on the project from Texas A&M University at Galveston, said.
“Among the different energy sources, coal is more of a threat than nuclear power,” he said. “For example, more radionuclides are released annually from coal-powered power plants than emissions from nuclear power plants. We need to use power sources which cause the least amount of damage and pose the lowest risk.”
The collaborative research project has discovered that nature may have a solution to contaminated environments. Microbes that exist in the contaminated areas are producing natural products such as enzymes that may change the chemical properties of these radioisotopes.
Researchers also discovered that organic compounds that strongly bind to iron can also play a key role in determining how certain radionuclides, such as plutonium, are absorbed to cells or soils.
All of these processes essentially do the same thing — pull radioactive material out of the water and into the soil to become part of the sediment cycle. The difference being the amount of time we are willing to give it to allow natural processes to ameliorate pollutant radionuclides. More research is needed to determine the conditions where natural organic compounds such as enzymes are most effective in immobilizing nuclear waste nuclides at contaminated sites.
Editor’s note: Robert Hosler is an Ocean and Coastal Resources major at Texas A&M University-Galveston. This article was written by as part of a seminar class and published to give the author some experience in writing for a general-readership periodical.