U.S. Army Europe
is using a new composting system to improve management
of solid waste. The results are increased Soldier safety
and a better quality of life in the field.
Armies around the globe have
always had to deal with the problem of solid waste. Today,
a large percentage of the Army’s
solid waste is packaging materials (such as cardboard, paper,
and plastic), waste food, and sewage sludge. While much of
the solid waste generated at base camps is biologically degradable,
it presents significant waste management challenges for the
Army. This is a particular concern when the Army operates in
countries that have few, if any, modern waste disposal facilities.
During the last 2 years, the U.S. Army Europe (USAREUR) Engineer
Support Operations Office tested a commercially available composting
system that converts up to 85 percent of the putrescible waste
(waste that decomposes and becomes putrified) generated at
base camps into a usable product. This system also greatly
reduces pathogens and minimizes odors and bio-aerosol emissions.
The compost produced by the system can be used in a variety
of ways, including erosion control, soil amendment, or application
to agricultural, forest, or reclaimed mined lands. [A soil
amendment is material added to soil to improve the soil’s
physical properties, such as its ability to retain water or
|A crew sets
up the AGILE Flex system. They place aeration tubes
on the ground before dumping waste heap on top of
the tubes. The semipermeable membrane cover is seen
on top of the green ISO shipping container, which
also houses blower fans, a computer, and office space.
Solid Waste Management Challenges
When contingency operations base camps are established initially,
solid waste landfills normally are not available and solid
waste is usually taken to a burn box to be incinerated using
diesel fuel. The incineration process requires approximately
1 gallon of fuel for each cubic meter of waste and reduces
the volume of waste by approximately
80 to 90 percent. The residual materials (for example, ash
and incompletely burned solid waste) then must be transported
to some other location for disposal.
However, many local waste disposal sites are burial pits or
excavation sites, and most of them lack liners, daily cover,
run-off controls, or other modern techniques used for managing
sanitary landfills. These disposal site conditions present
another set of significant environmental problems, such as
toxic leachate, vector attraction, and even greenhouse gas
creation. [Vector attraction refers to the characteristic of
sewage sludge to attract rodents, flies, mosquitoes, or other
organisms capable of transporting infectious agents.]
is placed on top of the aeration tubes, and the cover
is laid over the heap. Temperature- and oxygen-monitoring
probes are installed in the heap through the cover.
The process of burning solid waste, including wastes with
low BTU values such as dining facility and other organic
waste, creates other problems. [A “BTU” is
a “British thermal unit” and equals the amount
of heat required to raise the temperature of 1 pound of water
by 1 degree Fahrenheit. The BTU often is used in the United
States to describe the heat value of fuels.] The burning
waste emits toxic, acrid smoke, which has caused military
to complain about eye and lung irritation. At Camp Bondsteel
in Kosovo, Soldiers have sent numerous complaints up the
chain of command about smoke produced by incinerators.
Since troop safety is a vital concern, it is critical to
treat solid waste and sewage sludge effectively. Soldiers’ safety
and quality of life are enhanced by reducing pathogens associated
with sewage sludge and reducing the amount of solid waste
burned. It also is essential to minimize the volume and toxicity
solid waste disposed of at land disposal sites that lack
modern environmental controls. The USAREUR Engineer Support
Office has tested different methods to improve solid waste
management during contingency operations and thereby reduce
long-term environmental liabilities and risks.
compost in this photograph was used as soil amendment
in erosion-control projects at Camp Bondsteel.
A New Composting System
The practice of burning solid waste ended at Camp Bondsteel
in October 2005. The USAREUR Engineer Support Operations
Office, along with the German firm COMP–ANY GmbH and
Kellogg Brown & Root (KBR), now are using composting
combined with recycling and landfill disposal. After successful
pilot program testing during 2004 and 2005, a full-production
mobile aerated static heap composting system was deployed
at Camp Bondsteel in September 2005.
The new commercial system, AGILE Flex, incorporates semipermeable
membrane technology that—
Mitigates the effects of extreme weather on composting.
Accelerates the natural composting process.
Minimizes manpower costs.
Allows composting to occur within the confines of a small base
camp because the system reduces odors and vector attraction
by more than 90 percent.
Odors are reduced by the scrubbing effect of the semipermeable
GORE–TEX membrane cover, which also blocks vectors.
Currently, the Camp Bondsteel Directorate of Public Works
and KBR manage and compost solid waste consisting of sewage
dining facility waste, wood chips, shredded cardboard, paper,
and hay. These ingredients are mixed and placed in a heap
over air feeder aeration tubes that extend from a standard
Organization for Standardization] shipping container. A GORE–TEX
fabric cover is placed over the heap and held to the ground
with a water-filled fire hose. Temperature- and oxygen-monitoring
probes are inserted through the cover into the heap to record
temperature and oxygen
data. Blower fans, controlled by a computer located in the
ISO container, force air into the heap based on real-time
feedback from the probes.
During the initial 3-week processing period, bacterial activity is controlled
as the computer automatically adjusts the air flow to maintain optimum temperature
and oxygen levels in the heap. Internal compost temperatures easily reach 150
to 165 degrees Fahrenheit. After the initial 3-week period, the compost heap
is uncovered and moved to the opposite side of the ISO container. The heap then
is treated using the same procedure for an additional 3 weeks. After the total
6-week period, the compost is ready to be tested and used for soil amendment.
The AGILE Flex system has shown excellent results by minimizing pathogens and
other problems created by solid waste in contingency operations. The AGILE Flex
system increases composting efficiency by using cardboard and paper waste generated
by the base population to balance the carbon-to-nitrogen ratio in the heap. This
is critical to the successful composting of waste with a high nitrogen content,
such as sewage sludge and food or catering waste.
boxes of sewage sludge are stockpiled at Camp Bondsteel
in Kosovo. All of the sewage sludge in this photo
was composted during the early days of the pilot
study in 2004.
Composting will reduce fuel costs associated with burning solid waste. In
the past, the Army paid $65,000 for 1 year’s worth of JP–8 fuel
used as an accelerant to burn waste. Because of composting, that entire expense
will no longer be necessary. The USAREUR Engineer Support Operations Office
that composting also will require fewer man-hours of labor. After successfully
treating 100 percent of the sewage sludge and dining facility waste generated
by two base camps in Kosovo during 2004 and 2005, the Engineer Support Operations
Office firmly believes that this composting process will lead the Army into
the next generation of solid waste management systems for contingency operations.
The AGILE Flex treatment system has proven to be a powerful solid waste management
tool through its simplicity, reduced operating costs, reliability in all
weather conditions, and short processing time for the treatment. More importantly,
this system enhances force protection by reducing the need to use Soldiers
or escort solid wastes to off-site waste disposal areas. Because of its compact
(ISO container), mobile, and self-contained characteristics, this innovative
system is especially beneficial in contingency operations. The ability of
system to treat large amounts of solid waste successfully on site within
a short time period increases its value to the Army’s mission.
Stephen D. Stouter is a program manager in the Afghanistan
Engineer District, Army Corps of Engineers, in Kabul, Afghanistan.
He has a B.S. degree from Middle Tennessee State University.
Joseph Bost is the Chief of the Engineer Support Operations
Office, Office of the Deputy Chief of Staff, Engineer, at U.S.
Army Europe. A retired lieutenant colonel, he holds a B.S.
degree from Troy University and an M.S. degree from the University
of Southern California and is a graduate of the Army Command
and General Staff College.
James F. Lee is an environmental management officer in the
Engineer Support Operations Office, Office of the Deputy Chief
of Staff, Engineer, at U.S. Army Europe. He has a degree in
energy and environmental management from City University in