BLACKSBURG, Jan. 31, 1997 -- Virginia Tech
environmental engineers, working with the railroad, an Iowa tree
company, and a consulting firm, are attempting to use Mother Nature
to restore a site contaminated by a leaking creosote holding pond.
More importantly, they hope the knowledge gained from this project
will enhance the use of natural biological means to correct environmental
For railroads, the use of creosote to preserve
ties has been common practice since the 1800s. An easy method
to treat a railroad tie with the preservative was to dip it in
a creosote holding pond. One of these ponds is in Oneida, Tenn.,
where the lagoon was in use until 1973.
Seventeen years later, when the U.S. Army
Corps of Engineers rechanneled a nearby creek, areas of contamination
were then exposed and free to enter the newly constructed channel.
Despite measures that eventually eliminated the flow of the contaminated
groundwater to the channel, the site itself remains polluted.
The solution may be in the planting of the
stately poplar tree. The use of these fast growing, deciduous
plants was proposed by a consulting firm, Geraghty and Miller
Inc. Recent data indicate poplar trees can remediate a contaminated
water area due to their ability to draw the polluted groundwater
to their roots. Although the process is not yet well understood,
it appears that the contaminants are rendered harmless as they
interact in the area of the trees' roots. Plants, in general,
create a microbial environment near their roots that result in
the more rapid demise of pollutants.
"Engineers try to fight nature,"
says Simone Grace, an environmental engineer with Ecolotree, the
Iowa firm promoting the use of poplar trees. She adds, "Now,
the engineers are using nature."