Public Release: 

Plants Have Future As Environmental Clean-Up Agents

Kansas State University

MANHATTAN -- It's a problem occurring across the country. Hazardous chemicals left behind in landfills and dump sites threaten water supplies and health. Clean-up is expensive and time-consuming.

But research at Kansas State University into a process known as plant-based bioremediation is showing that an answer to those problems could be helped by something as simple as planting a tree.

"Essentially, bioremediation is using organisms to clean up contaminants," said Larry Davis, professor of biochemistry. "Usually it means bacteria or fungi-emphasizing plants which are present in the root zone."

In essence, the vegetation serves as a pump bringing contaminated water close to the surface. Depending on the type of chemical present, bacteria on the plant roots can feed on some types of chemicals, while other chemicals are brought closer to the surface, which can hasten their degradation because oxygen is present.

"In some cases, we have actually seen 10 pounds per acre a day removed," Davis said. "It really depends on what's present there."

In either case, using plant-based bioremediation is cheaper then more traditional methods of clean-up such as pumping and treating or excavation, according to Larry Erickson, professor of chemical engineering.

"I would say society is going to save many millions of dollars," he said. "We're finding the use of vegetation has use in a number of environments and a number of problems."

That's hopefully going to be the case in Riley County, which is the home county of both K-State and the city of Manhattan. Facing clean-up costs at a closed landfill, they drew on K-State's expertise in the area of bioremediation for a solution.

Drawing on work by both students and faculty, the county decided to adopt bioremediation as a solution. This spring, 5,000 poplar trees will be planted at the site.

"It's really an application of university research to a county level," said Ann Feyerharm, special projects assistant for Riley County. "I never would have heard of it if it hadn't been for Dr. Erickson and Dr. Davis."

Feyerharm said one of the most attractive aspects of bioremediation to Riley County was the cost. Traditional clean-up methods could have cost an estimated $4 million in the first year, and $8 million over 20 years. The total cost of the bioremediation is expected to be around $15,000.

But the aesthetic qualities of bioremediation were also an attraction. Feyerharm said the planting of the trees will help control erosion problems and attract wildlife, something traditional treatments wouldn't do.

"We think this a no lose opportunity for us," Feyerharm said.

Erickson and Davis, along with other K-State professors, are continuing research into bioremediation, both in areas of genetic research and practical application. The Great Plains/Rocky Mountain Hazardous Substance Research Center, a consortium of 14 universities with headquarters at K-State, funds a number of bioremediation research projects across the country.

Considering there are approximately 300,000 sites across the United States in need of clean-up, many are hoping research will lead to a cleaner environment.

"We're doing some cutting edge work," Erickson, who serves as director of the center, said. "One of our goals is to bring useful technology to the field.

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