Conveyor system used to
transport and prepare army
garbage before it's ground
into a pulp. Garbage is
put through a hydrolyzer
that uses high temperature
and steam pressure to sterilize
it. Photo taken at and provided
by the U.S. Army Engineer
Research and Development Center,
Construction Engineering Research
Laboratory, Champaign, Illinois.
The U.S. Army is trying to address several environmental problems.
One is that it's running out of space for trash disposal. The Army spends
$100 million to dispose of 2 million tons of garbage each year in 12
landfills. These landfills are filling up and new ones can't be built.
A second problem is that heavily used Army training areas are becoming
bare of vegetation because of constant traffic from heavy equipment
and foot soldiers. This leads to soil erosion and compaction problems,
which make it difficult to revegetate these areas.
The Agricultural Research Service
(ARS) has teamed up with the Army to help solve these problems by converting
trash into a pulp that can be used to improve soil and help establish
Instead of being dumped in landfills, garbage is placed on a conveyor
system that separates out metals. The leftover material can then be
ground into a pulp. This system also uses high-temperature and high-pressure
steam to sterilize and help break down the pulp. It's then dried and
air-separated to remove plastics. The final product has a neutral pH
and contains nitrogen, phosphorus, and potassium.
ARS, led by soil scientist H. Allen Torbert of the National Soil Dynamics
Laboratory, Auburn, Alabama, planted native grasses on two Army bases
after this pulp material was applied to the Army's land. Torbert is
studying the chemical properties of soil after pulp introduction. Soil
scientist Ken Potter of ARS's Blacklands Research Center, in Temple,
Texas, works with Torbert in studying physical properties of soil after
pulp is added.
On the first 2-year research plots, located at Fort Campbell, Kentucky,
native grasses were successfully established and a significant increase
in plant biomass occurred between the first and second year of study,
according to Torbert. The researchers were able to make the soil fertile
"We're doing an excellent job of revegetating training areas in
Fort Benning, Georgia," Torbert says of their second research location.
These soils were very poor and required more pulp material. Restoration
efforts were a huge success in the first year, with the planted native
grass species becoming well established.
The Army agrees with Torbert's assessment. "I'm convinced it is
indeed a success at both locations," says Dick Gebhart, project
manager at the U.S. Army Engineer Research & Development Center,
Champaign, Illinois. Deborah Curtin, another project manager, says there
is great interest in expanding these projects to other military bases.
What the researchers learn in this study should be applicable to civilian
turfs as well, such as home lawns, golf courses, and parks. The findings
could also help improve degraded agricultural soils.By David Elstein, Agricultural
Research Service Information Staff.
This research is part of Soil Resource Management (#202) and Manure
and Byproduct Utilization (#206), two ARS National Programs described
on the World Wide Web at www.nps.ars.usda.gov.
H. Allen Torbert is with
the USDA-ARS National
Soil Dynamics Laboratory, 411 S. Donahue Drive, Auburn, AL 36832;
phone (334) 844-3979, fax (334) 887-8597.
"From Trash to Grass: Revegetating Army Training Grounds"
was published in the July
2004 issue of Agricultural Research magazine.