Bioremediation may be effective in helping to clean up contaminated soil, water.
Buried under 243 acres in an East
Tennessee valley adjacent to the Oak Ridge National Laboratory's
Y-12 National Security Complex, toxic waste from weapons manufacturing at the
facility between 1951 and 1983 leaches into ground water that extends in
radioactive plumes for miles from the contaminated site.
But soon, Florida State University
(FSU) associate professor Joel Kostka and his oceanography department team will
help clean up the mess.
During the course of a forthcoming
five-year study funded by the U.S. Department of Energy, FSU researchers will
be testing a natural method called bioremediation -- the stimulation of
naturally occurring microbes that Kostka calls "hidden heroes" -- to
promote bacterial growth in the soil subsurface that scrub it of potentially
deadly radioactive metal.
If bioremediation proves successful
on the uranium, technetium, nitrate and other potentially lethal leftovers at
the Oak Ridge site, the process
should work to mitigate contamination at more than 7,000 other sites nationwide
-- and do so more economically and effectively than most conventional methods.
"The stakes are high and the
impact potentially huge," Kostka reveals. Together, those 7,000 U.S.
sites encompass an estimated 1.7 trillion gallons of contaminated water --
that's about four times the nation's daily water consumption -- and about 40
million cubic meters of contaminated soil.
Kostka has a five-year, $1 million
share of the total $15 million in U.S. DOE funding for the project, which
includes research teams from FSU and multiple universities and national
laboratories across the country.
Together, the partners will develop
models to help predict the rate at which contamination levels drop when using
natural methods such as bioremediation and artificial techniques such as
chemical additions and pH adjustments. Subsurface changes are monitored using
geophysical methods that send acoustic, electric and other signals into the
Kostka's research team from FSU's
oceanography department will lead the subsurface microbiology portion of the
contamination such as that found at the Oak Ridge Field Research Center (ORFRC)
where we will be working is a huge global issue," Kostka says. "It
affects not only the U.S.
but in particular, also Eastern Europe, Canada
and South America, and the costs of cleanup are
projected in the billions, if not trillions, of dollars in the U.S.
"As it now stands,
bioremediation, which is potentially much cheaper than current technologies,
has not been used much at all, but it should be," he asserts.
"Subsurface aquifers, where
most of the radioactive contamination resides, are primary sources of ground
water used for drinking, and contaminated aquifers tend to be extreme environments
where microorganisms dominate. These microbes are the 'hidden heroes' that do
the work of bioremediation. Our new project will provide the basic science
necessary to deploy bioremediation technologies at the scales necessary for
them to be effective at U.S. DOE sites."
In addition, the ORFRC has funded
Kostka's FSU lab to develop and maintain a genetic database of genes of
organisms that are present in the Oak Ridge
"With the genetic database and
associated cutting-edge genomics techniques, my lab will determine and predict
the functioning or metabolism of subsurface microbial groups that catalyze key
chemical reactions for contaminant removal from ground water," he says.
Microbes May Help Remediate Toxic Sites
February 14, 2007