Currently,
when a company has a chemical spill, the company will use a pumping system in
attempt to remove the chemical out of the ground so that it will not
contaminate the ground water. Michael Ball, owner of Kansas WATER Training,
said that it is nearly impossible to pump out all the contaminants and it is an
expensive method. However,
Dr. J.F. Devlin, a geology professor and hydrologist at the University of
Kansas is researching the new method of removing these chemicals, Permeable
Reactive Barriers (PRB). Permeable Reactive Barriers use iron to as a reactant
to remove harmful chemicals from the ground water as it flows through a trench.
Devlin's
research includes trying to get a direct measure of how fast the water moves in
the ground along with the study of granular iron and how it reacts with
different pollutants in groundwater. Working with Devlin in his research is Dr.
George Tsoflias, also a geology professor at the University. Tsoflias uses
ground-penetrating radar (GPR) to test how the water and its contaminants are
moving throughout the subsurface. Tsofias said that the traditional method for
measurement is to use wells, but that only gives you the velocity of the ground
water at that particular point and it is not possible to predict what is
happening away from the well. His non-invasive method of the GPR allows him to
see how the water moves and the flow pattern of the contaminants, which is how
it helps Devlin. "It's
sort of like a cat scan like doctors use on the human body, it gives us a
three-dimensional view of the sub-surface," Tsofias said. Devlin's
students are helping him with the other half of his research. The students in
his Special Studies in Geology class are setting up experiments in preparation
for testing different types of contaminants and how they react to iron. Garrett
Johnson, Fredonia senior, said that he is setting up two gems (beakers) with
100 percent carbonate solution with a magnetic rod inserted that includes the
iron. These beakers will set and let the iron age for about three days. When
the experiment begins, Garrett will be taking samples every five minutes. After
he is completed with the carbonate solution, he will do the same thing with a
solution of perchlorate and analyze the samples. "We
are hoping that one solution will speed up the reaction with iron and one will
slow it down, but we don't know which one." Johnson said. Devlin
said that these permeable reactive barriers apply to people's everyday lives. "It
takes decades to get things out of the ground and this is a system that doesn't
require pumping or maintenance." Devlin said. He said that even though pouring
one of these trenches and filling it with iron is very expensive, it will be
more economic in the long run--unlike the pumping method. Devlin said that there
are 100-200 PRBs in the ground now and most of them are performing well. One
PRB is located at the U.S. Department of Energy's Kansas City Plant in Kansas
City, Mo. It was installed in April of 1998. Devlin said that the Kansas City
PRB is interesting because it is a split from the river and the river changed
course, making the trench not quite accurate. However, it is still successful
with only a ten percent leak. Other
PRB locations include Sunnyvale, CA, Colorado, New York, Florida, as well as
Europe and the Far East. Although
the installation of a PRB is more expensive to begin than the traditional
pumping method, Devlin believes that it will be cheaper in the long run and is
necessary during this economic downfall.
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