UF Using New Technology To Speed Contamination Cleanup
August 13, 1998
GAINESVILLE — University of Florida researchers are using a new technology that could reduce the cleanup time of some stubborn hazardous waste sites from years to days.
“We are developing and testing faster, cheaper and better cleanup technologies compared to today’s common technologies,” said Suresh Rao, a graduate research professor in UF’s Institute of Food and Agricultural Sciences and director of the university’s Center for Natural Resources.
“Cleanup of hazardous waste sites is a nationwide problem, with one in four Americans living near one of the thousands of sites spread across the country,” Rao said. “Analysts estimate that nearly $1 trillion would be needed over the next 30 to 50 years to clean up hazardous waste sites nationwide.”
The new cleanup technology is removing cleaning solvents trapped underground in tests under way at a former dry cleaner’s site in Jacksonville. “Today’s standard approach would have taken years to get the same result that we are getting in only a few weeks,” Rao said.
The Jacksonville project is a follow-up to tests UF conducted with the U.S. Environmental Protection Agency (EPA) at Hill Air Force Base in Utah from 1995 to 1997. In Utah, the new approach removed about 1,000 times more contaminants than flushing with water alone, currently the standard method, according to Rao.
The Florida Department of Environmental Protection (DEP) and EPA each have provided about $200,000 for the Jacksonville project, which the environmental consulting firm Levine-Fricke-Recon of Tallahassee is conducting in cooperation with UF’s colleges of agriculture and engineering. UF’s Center for Solid and Hazardous Waste Management is providing $40,000.
The EPA is involved because of the promise of the technology in removing chlorinated organic solvents, said Walter Kovalick, director of the agency’s Technology Innovation Office. These contaminants — used as dry-cleaning fluid and industrial solvents — are heavier than water and are tough to budge once they settle in pockets or pools underground.
“We don’t know how to remove this type of pollution effectively at a reasonable cost,” Kovalick said. “This project is the first effort to clean up the main source of contamination for an entire site with this innovative technology.
“Public-private partnerships like this one that push the envelope of applied research into practice are exciting.”
The DEP is involved because it is exploring innovative technologies for its dry-cleaning solvent cleanup program, which the Florida Legislature established in 1995. Fees on dry cleaners and dry-cleaning services pay for this program, which has been funded for $14 million this fiscal year and has annual revenues of $7 million.
“It’s tough to remove dry-cleaning solvents that seeped into the ground years ago due to accidental discharges or poor ways of disposing of solvent,” said Doug Fitton, a DEP environmental specialist.
“We expect to fall short of funds if we cannot find cost-effective ways to address the more than 975 sites identified in the program statewide,” Fitton said. “Cost-effective innovative technologies would allow our program to address more sites, and the technologies could well be carried over to similar programs in other states.”
The technology UF is testing involves flushing contaminated sites with a mixture of alcohols, detergents and water instead of using only water, said Mike Annable, a UF associate professor of environmental engineering. In Jacksonville, a flushing solution is being pumped into the ground through three injection wells and then extracted through six other wells.
“There has been a fear that using alcohols and detergents as flushing agents would further contaminate sites,” Annable said. “However, the oil industry has used this technology for years to recover crude oil, and we’re just extending its application.
“In the Utah project, we showed that the flushing agents didn’t pose a problem, and we were able to pump all of the injected alcohols and detergents from the test area.”
UF and EPA researchers also are examining how well helpful bacteria that digest toxic chemicals will perform after the alcohol flushing is completed.
“It’s possible that after the flushing removes the vast majority of the dry-cleaning solvents, the microbes will be able to do the mop-up,” said Andrew Ogram, a UF assistant professor of soil and water science. “But the flushing solution is bound to kill some of the helpful bacteria and could reduce their effectiveness in the final cleansing of the site.”
“Cleaning up contaminated sites faster and less expensively benefits everyone,” said Kevin Warner, an engineer with Levine-Fricke-Recon. “If the approach being used becomes widely accepted, citizens no longer will have hazardous waste sites in their neighborhoods, and the number of hazardous industrial and military waste sites will be reduced.”
Collaboration between public agencies and private companies on projects such as the Jacksonville one is needed, said Rao, who recently headed a 16-member National Research Council committee on new approaches to toxic-waste cleanup.
“It is important to leverage public funds to help restore the promise of the Superfund law and to clean up more sites as innovative technologies are deployed,” he said. “Today, many companies prefer to pay legal fees to delay starting cleanup efforts instead of absorbing the high cost of the standard treatment, which often is not guaranteed to meet required cleanup goals. We hope to reduce the costs and improve the effectiveness of cleanup technologies to the point that companies will prefer to get the job done instead of stalling.”