United States
Environmental Protection
Agency
Solid Waste
and Emergency Respci
(5306W)
Compost—New Applications
For an Age-Old Technology
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What Are the Environmental
to Using Compost?
The use of compost can result in a variety of environmental benefits. The following are a few of the most
important benefits in three main areas.
Soil Enrichment:
• Adds organic bulk, humus,
and cation (positively
charged ions) exchange to
regenerate poor soils.
• Suppresses certain plant
diseases and parasites.
• Increases soil nutrient
content and water reten-
tion in both clay and
sandy soils.
• Restores soil structure
after natural soil micro-
organisms have been
reduced by the use of
chemical fertilizers.
• Reduces fertilizer require-
ments by at least 50 per-
cent.
• Solves specific soil, water,
and air problems, when
specially tailored.
Pollution Remediation:
• Absorbs odors and
degrades VOCs.
• Binds heavy metals and
prevents them from
migrating
to water resources, being
absorbed by plants, or
being bioavailable to
humans.
• Degrades or completely
eliminates wood preserva-
tives, petroleum products,
pesticides, and certain chlo-
rinated and nonchlorinated
hydrocarbons in contami-
nated soils.
Pollution Prevention:
• Avoids methane produc-
tion and leachate forma-
tion in landfills by
diverting organics from
landfills into compost.
" Prevents pollutants in
storm-water runoff from
reaching water resources.
• Prevents erosion and silt-
ing on embankments adja-
cent to creeks, lakes, and
rivers.
• Prevents erosion and turf
loss on roadsides, hillsides,
playing fields, and golf
courses.
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Believe it or not, compost can:
• Cost-effectively remediate cont-
aminated soils similar to those
found at brownfields and
Superfund sites.
• Remove solids, oil, grease, and
heavy metals from stormwater
runoff.
• Capture and destroy 99.6 per-
cent of industrial volatile organ-
ic chemicals (VOCs) in
contaminated air.
• Degrade or completely elimi-
nate wood preservatives,
petroleum products, pesti-
cides, and certain chlorinated
and nonchlorinated hydrocar-
bons in contaminated soil.
Drastically reduce the need for
pesticides and fertilizers.
Facilitate reforestation, wedands
restoration, and habitat revital-
ization efforts by amending con-
taminated, compacted, and
marginal soils.
Provide cost savings of at least
50 percent over conventional
soil, water, and air pollution
remediation technologies,
where applicable.
1 Utilize 70 percent of the organ-
ic waste generated in the
United States as feedstock for
various composts.
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Innovative Uses of Compost
Bioremediation and
Pollution Prevention
ach year agricultural effluents, industrial residues, and industri-
al accidents contaminate surface waters, soils, air, streams, and
reservoirs. A new compost technology, known as compost biore-
mediation, is currently being used to restore contaminated soils, manage
stormwater, control odors, and degrade volatile organic compounds (VOCs).
Compost bioremediation refers to the use of a biological system of
micro-organisms in a mature, cured compost to sequester or break down
contaminants in water or soil. Micro-organisms consume contaminants in
soils, ground and surface waters, and air. The contaminants are digested,
metabolized, and transformed into humus and inert byproducts, such as
carbon dioxide, water, and salts. Compost bioremediation has proven effec-
tive in degrading or altering many types of contaminants, such as chlori-
nated and nonchlorinated hydrocarbons, wood-preserving chemicals,
solvents, heavy metals, pesticides, petroleum products, and explosives.
Compost used in bioremediation is referred to as "tailored" or "designed"
compost in that it is specially made to treat specific contaminants at spe-
cific sites.
The ultimate goal in any remediation project is to return the site to its
precontamination condition, which often includes revegetation to stabilize
the treated soil. In addition to reducing contaminant levels, compost
advances this goal by facilitating plant growth. In this role, compost pro-
vides soil conditioning and also provides nutrients to a wide variety of
vegetation.
) Printed on paper that contains at least 20 percent postconsumer fiber.
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Soil Bioremediation
Heavy Metal Contamination
r. Rufus Chaney, a senior research
agronomist at the U.S. Department of
Agriculture, is an expert in the use of
compost methods to remediate metal-
contaminated sites. In 1979, at a denud-
ed site near the Burle Palmerton zinc smelter
facility in Palmerton, Pennsylvania, Dr. Chaney
began a remediation project to revitalize 4 square
miles of barren soil that had been contaminated
with heavy metals.
Researchers planted Merlin Red Fescue, a metal-
tolerant grass, in lime fertilizer and compost made
from a mixture of municipal wastewater treatment
sludge and coal fly ash. The remediation effort was
successful, and the area now supports a growth of
Merlin Red Fescue and Kentucky Bluegrass.
Chaney has also investigated the use of com-
post to bioremediate soils contaminated by lead
and other heavy metals at both urban and rural
sites. In Bowie, Maryland, for example, he found a
high percentage of lead in soils adjacent to houses
painted with lead-based paint. To determine the
effectiveness of compost in reducing the bioavail-
ablility of the lead in these soils, Chaney fed both
the contaminated soils and contaminated soils
mixed with compost to laboratory rats. While both
compost and soil bound the lead, thereby reducing
its bioavailability, the compost-treated soil was
more effective than untreated soil. In fact, the rats
exhibited no toxic effects from the lead-contami-
nated soil mixed with compost, while rats fed the
untreated soil exhibited some toxic effects.
Photo courtesy of U.S. Department of Agriculture. ARS, Beltsville, MD.
Soil near the Burle Palmerton zinc smelter facility was so contaminated
with heavy metals that residents of nearby towns were unable to grow
grass lawns and instead used stones and pebbles as shown above.
In another study, Dr. Lee Daniels and P.D.
Schroeder of Virginia Polytechnic Institute,
Blacksburg, Virginia, remediated a barren site con-
taminated with sand tailings and slimes from a
heavy mineral mining plant. The application of
yard waste compost revitalized the soil for agricul-
tural use. The compost was applied at the rates of
20 tons per acre for corn production and 120 tons
per acre for a peanut crop.
Photos courtesy of Virginia Polytechnic Institute, Blacksburg, VA.
A heavy mineral mining plant site with sand tailings and slime was
remediated for corn and peanut production with the application of
yard waste compost.
Organic Contaminants
Dr. Michael Cole, an expert in the degradation
of organic contaminants in soil, remediated soil
containing 3,000 parts-per-million (ppm) of
Dicamba herbicide to nondetectable levels in 50
days. Cole mixed wood chips and mature compost
into soil to make the combined substrate 10 per-
cent (by volume) compost and wood chips and 90
percent contaminated soil. According to Dr. Cole,
Dicamba does eventually degrade in nonamended
soil; however, that process takes years instead of
days. In addition to speeding up the bioremedia-
tion process, use of compost can also save money.
Traditional remediation by landfilling and inciner-
ation can cost up to five times more than bioreme-
diation by composting technology.
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According to Dr. Cole, compost bioremediation,
more than any other soil cleanup technique,
results in an enriched soil end product and leaves
the earth in better condition than before it was
contaminated.
Petroleum Hydrocarbon Contamination
Soil at the Seymour Johnson Air Force Base
near Goldsboro, North Carolina, is contaminated as
a result of frequent jet fuel spills and the excava-
tion of underground oil storage tanks (USTs).
Remediation of several sites on the base is an ongo-
ing project since materials are continually loaded
or removed from USTs, and jets are continually
refueled. The base deals with a variety of petrole-
um contaminants, including gasoline, kerosene,
fuel oil, jet fuel, hydraulic fluid, and motor oil.
In 1994, the base implemented a bioremediation
process using compost made from yard trimmings
and turkey manure. Prior remediation efforts at
Seymour involved hauling the contaminated soil to
a brick manufacturer where it was incinerated at
high temperatures. Compared to the costs of haul-
ing, incinerating, and purchasing clean soil, biore-
mediation with compost saved the base $133,000
in the first year of operation. Compost bioremedia-
tion also has resulted in faster cleanups, since pro-
jects are completed in weeks instead of months.
The remediation process at Seymour includes
spreading compost on a 50- by 200-foot unused
asphalt runway, applying the contaminated soil,
then another layer of compost. Workers top off the
pile with turkey manure. Fungi in the compost
produce a substance that breaks down petroleum
hydrocarbons, enabling bacteria in the compost to
metabolize them. Clean-up managers determine the
ratio of soil to compost to manure, based on soil
type, contaminant level, and the characteristics of
the contaminants present. A typical ratio consists
of 75 percent contaminated soil, 20 percent com-
post, and 5 percent turkey manure. A mechanical
compost turner mixes the layers to keep the piles
aerated. After mixing, a vinyl-coated nylon tarp
covers the piles to protect them from wind and
rain, and to maintain the proper moisture and
temperature for optimal microbial growth.
Stormwater Management
tormwater runoff is excess water not
absorbed by soil after heavy rains. It
flows over surfaces such as roads,
parking lots, building roofs, driveways,
lawns, and gardens. On its journey to
larger bodies of water (streams, lakes, and
rivers), municipal and industrial stormwater can
carry a wide range of potentially harmful envi-
ronmental contaminants, such as metals, oil and
grease, pesticides, and fertilizers. These types of
contaminants pollute rural water, damage recre-
ational and commercial fisheries, and degrade
the beauty of affected waterways, among other
things.
Stormwater runoff must be treated before it is
discharged into water to meet the U.S.
Environmental Protection Agency's National
Pollutant Discharge Elimination System regula-
tions. To comply, some municipalities and
industries are turning to solutions that involve
compost technology instead of more expensive
traditional treatment methods, such as vegetated
filter strips or grassy swales (phytoremediation)
and holding ponds. These traditional methods
require much larger tracts of land than methods
utilizing compost and are limited in their
removal of contaminants. In one industrial area,
for example, a traditional holding pond required
3.5 acres and cost $45,000, while a compost
stormwater system, designed to handle the same
amount of runoff, required only 0.5 acre,
required less maintenance, and cost $17,300.
Compost Stormwater Filters
The compost stormwater filter (CSF), one type
of bioremediator, is a large cement box with
three baffles to allow water to flow inside (see
figure on page 4). The CSF is designed to remove
floating debris, surface scum, chemical contami-
nants, and sediment from stormwater by allow-
ing it to pass through layers of specially tailored
compost. The porous structure of the compost
filters the physical debris while it degrades the
chemical contaminants. Scum baffles along the
side of the unit trap large floating debris and
surface films.
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Typical CSF Unit
Flow
Spreader I
Energy
Dissipator
The CSF bioremediator removes contaminants from stormwater by allowing water to flow through layers of
specially tailored compost.
This innovative stormwater filtration and biore-
mediation system uses a relatively small volume of
specially tailored compost made from leaves. The
compost is formulated to remove over 90 percent of
all solids, 85 percent of oil and grease, and between
82 to 98 percent of heavy metals from stormwater
runoff. A CSF typically has low operating and
maintenance costs and has the ability to treat large
volumes of water—up to 8 cubic feet per second.
When the compost filter is no longer effective, it
can be removed, tested, recomposted to further
remove any contaminants, and used in other com-
post applications, such as daily landfill cover since
the metals are bound by the compost.
Disposal of VOCs and Odor Control
ompost bioremediation technologies
also have been developed to remove
VOCs that cause disagreeable or harm-
ful odors in air. The removal process
involves passing the contaminated air
through a patented, tailored compost. The compost
functions as an organic medium containing micro-
organisms that digest the organic, odor-causing
compounds. Industrial facilities have made use of
this compost technology to remove VOCs at the 99
percent level.
Billions of aerosol cans are manufactured and
used annually in the United States in households,
businesses, and industry. Many of these cans carry
residues of paints, lubricants, solvents, cleaners,
and other products containing VOCs. Disposing of
used aerosol cans represents a significant expendi-
ture, both to the communities that collect them
through household hazardous waste programs and
to the businesses and industry that generate, han-
dle, treat, or store these wastes.
Activated carbon is one technology that tradi-
tionally has been employed to treat these cans prior
to disposal. Canisters of carbon are used to physi-
cally adsorb VOCs from the cans. Activated carbon,
however, does not destroy the VOCs, but merely
stores them. Thus, once the carbon canisters
become saturated, they, in turn, must be
Biofiltration vs. Bioremediation
Biofiltration implies physically separat-
ing particles based on their sizes.
Bioremediation, by contrast, implies a
biochemical change as contaminants
or pollutants are metabolized by micro-
organisms and broken down into harm-
less, stable constituents, such as
carbon dioxide, water, and salts.
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disposed of. This adsorbtive compost technology is
more suitable for some types of VOC-containing
products than is activated carbon, which is a poor
adsorber of acetone.
Vapor-phase biofilters using compost are gaining
increasing attention as an alternative technology for
treating aerosol cans. This growth is due, in part, to
the high cost of conventional treatment and disposal
methods, as well as to new regulations concerning
VOC emissions from hazardous waste storage tanks
and containers. Unlike conventional VOC control
technologies, such as activated carbon, biofilters actu-
ally break down hazardous contaminants into harm-
less products. They also offer low capital, life-cycle,
and operating costs—and require minimal mainte-
nance and energy. The energy required to power a
100 cfm airflow unit, according to the manufacturer,
is rated at 20 amps. At 8 cents per kilowatt hour, the
cost of the requisite electricity is estimated at $1.80
per day. Additionally, according to one manufacturer,
vapor-phase biofilters maintain a consistent VOC
removal efficiency of 99.6 percent, even when
exposed to heavy or uneven surges of toxics.
Control of Composting Odors
Rockland County, New York, recently
announced construction of a composting facility
with America's first large, industrial-sized, odor-
control bioremediation system. The enclosed
55,000-square-foot facility will be fitted with a
compost filtration system that can process 82,000
cubic feet of air per minute. The air will be treated
using ammonia scrubbers, then forced into an
enclosure stacked with compost and other organic
materials that function together as an air filtration
system. The system binds odorous compounds,
which the micro-organisms in the compost then
degrade. This system has allowed the Rockland
County Authority to obtain a contractual guarantee
of no detectable odor at or beyond the site proper-
ty line from the contractor awarded the design,
construction, and operating contract.
Biofilters in Municipal Use
By converting its disposal operation from strictly
landfilling to one that utilizes a vapor-phase biofil-
ter, the Metro Central Household Hazardous Waste
collection facility in Portland, Oregon, saved nearly
$47,000 in hazardous waste disposal costs over an
18-month period. The facility used vapor-phase
Vapor-Phase Biofiltration
One application of biofiltration technology
involves placing punctured cans, contami-
nated rags, or other items in the lower
chamber of the biofilter. Next, the entire unit
is heated to vaporize the contaminants.
A small amount of air is then injected into
the system to draw the now gaseous conta-
minants through two separate layers of a
compost-rich biomatrix. The bulk of the con-
taminants are absorbed by the biomatrix at
the first level, where most of the microbial
activity takes place. The upper level serves
as a surge control layer (to treat heavy or
uneven surges of VOCs). Micro-organisms
living in the biomatrix metabolize the
absorbed organics as food, converting the
pollutants into carbon dioxide and water
vapor.
Compost
Tray
Direction of
Air Flo
Compost -
Tray
In a vapor-phase biofilter, air draws volatilized contam-
inants upward through two trays of tailored compost.
Micro-organisms in the compost metabolize the contam-
inants, converting them into carbon dioxide and water
vapor.
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Benefits and Disadvantages of Using Vapor-Phase Biofilters
Benefits
• Low capital costs
• Low operating costs
• Limited energy and
maintenance requirements
• High reliability
• Consistent pollutant
removal
Consistent destruction
rates
No hazardous combustion-
related byproducts
Destroys VOCs, and thus
does not require secondary
disposal (unlike activated
carbon)
Disadvantages
• Requires consistent
loadings
• Requires more square
footage of space than con-
ventional disposal methods
biofilters to remediate over 38,000 aerosol cans. As
a result, it lowered its disposal costs from $505 per
loose-packed drum to $265 per drum (from $2.35
per can to $1.30), since the cans were no longer haz-
ardous and did not need to be handled as such.
References
Cole, M.A., X. Liu, and L. Zhang. 1995. Effect of compost
addition on pesticide degradation in planted soils. In
Bioremediation of recalcitrant organics. Edited by R.E.
Hinchee, D.B. Anderson, and R.E. Hoeppel. Columbus:
Battelle Press.
Chaney, R.L., and J.A. Ryan. 1994. Risk based standards
for arsenic, lead, and cadmium on urban soils. Frankfort:
Dechema.
Chaney, R.L. et al. Phytoremediation potential of Thlaspi
caerulescens and bladder campion for zinc-and-cadmi-
um-contaminated soil. Journal of Environmental Quality.
23: 1151-1157.
Fordham, Wayne. 1995. Yard trimmings composting in
the Air Force. Biocyde. 36: 44.
Garland, G.A., T.A. Grist, and R.E. Green. 1995. The com-
post story: From soil enrichment to pollution remedia-
tion. Biocyde. 36: 53-56.
SEPA
United States
Environmental Protection Agency
(5306W)
Washington, DC 20460
Official Business
Penalty for Private Use
$300
Schroeder, Philip D. 1997. Restoration of prime farm land
disturbed by mineral sand mining in the upper coastal
plains of Virginia. Master's Thesis, Virginia Tech.
Stewart, W.C., and R.R. Thorn. 1997. Test results and eco-
nomics of using an innovative, high-rate, vapor-phase
biofilter in industrial applications. Portland. Typeset.
Stewart, W.C. 1994. Compost stormwater filter engineer-
ing system. Environmental Excellence Award and
Innovator of the Year Award Presented by the Association
of Washington State Business. Mimeographed.
For More Information
This fact sheet and other information about solid waste
issues are available in electronic format on the Internet at
http://www.epa.gov/osw; select "Reduce, Reuse, Recycle."
Use Internet e-mail to order paper copies of documents.
Include the requestor's name and mailing address in all
orders. Address e-mail to: rcra-docket@epamail.epa.gov.
Paper copies also may be ordered by calling the RCRA
Hotline. Callers within the Washington Metropolitan
Area must dial 703 412-9810 or TDD 703 412-3323
(hearing impaired). Long-distance callers may call
800 424-9346 or TDD 800 553-7672. The RCRA Hotline
operates weekdays, 9 a.m. to 6 p.m.
Mail written document requests to the RCRA
Information Center (5305W), U.S. EPA, 401 M Street,
SW., Washington, DC 20460.
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Innovative Uses of Compost
Erosion Control, Turf
Remediation, and Landscaping
ompost has been viewed as a valuable soil amendment for
centuries. Most people are aware that the use of compost is an
effective way to improve plant growth. Compost-enriched soil
can also reduce erosion, alleviate soil compaction, and help
control disease and pest infestation in plants. These beneficial uses of
compost can increase healthy plant production, help save money, reduce
the use of chemical fertilizers, and conserve natural resources.
Compost used for a specific purpose or with a particular soil type
works best when it is tailor-made or specially designed. For example,
compost that is intended to prevent erosion might not provide the best
results when used to alleviate soil compaction, and vice versa. Technical
parameters to consider when customizing a compost mixture include
maturity, stability, pH level, density, particle size, moisture, salinity, and
organic content, all of which can be adjusted to fit a specific application
and soil type.
Compost Technology to Control Erosion
ccording to the U.S. Department of Agriculture, the United
States loses more than 2 billion tons of topsoil through ero-
sion each year. Erosion occurs when wind and rain dislodge
topsoil from fields and hillsides. Stripped of its valuable top
layer, which contains many essential nutrients, the soil left behind is
often too poor to sustain good plant growth. Eroded topsoil can also be
carried into rivers, streams, and lakes. This excess sediment, sometimes
containing fertilizers or toxic materials, threatens the health of aquatic
organisms. It can also compromise the commercial, recreational, and aes-
thetic value of water resources. As a result, preventing erosion is essen-
tial for protecting waterways and maintaining the quality and
productivity of soil.
) Printed on paper that contains at least 20 percent postconsumer fiber.
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Controlling Erosion in Construction
and Road Building
Erosion is a naturally occurring process; howev-
er, it is often aggravated by activities such as road
building and new construction. At the beginning
of some construction projects, all vegetation and
topsoil is removed, leaving the subsoil vulnerable
to the forces of erosion. On steep embankments
along roads and highways, compost can be more
effective than traditional hydromulch at reducing
erosion and establishing turf because compost
forms a thicker, more permanent growth due to its
ability to improve the infrastructure of the soil.
Depending on the length and height of a partic-
ular slope, a 2- to 3-inch layer of mature compost,
screened to 1/2 to 3/4 of an inch and placed
directly on top of the soil, has been shown to con-
trol erosion by enhancing planted or volunteer
vegetation growth. On steep slopes, berms
(mounds) of compost at the top or bottom of
slopes can be used to slow the velocity of water
and provide additional protection for receiving
waters. Because of its ability to retain moisture,
compost also helps protect soil from wind erosion
and during droughts. ± A
I Controlling Erosion in Road Construction
The Federal Highway Administration (FHWA), of
the U.S. Department of Transportation and the
U.S. Environmental Protection Agency, recently
conducted an erosion control demonstration project
that compared mature yard trimmings compost that
met FHWA specifications with hydromulch, a sub-
stance traditionally used for controlling erosion on
roadside embankments. The purpose of the study
was to determine the effectiveness of mature yard
trimmings compost compared with hydromulch in
establishing Fescue grass.
The project site was at a newly constructed inter-
section in suburban Washington, DC. Two
embankments with steep slopes were selected.
The first embankment had a 2 to 1 slope; the sec-
ond had a 3 to 1 slope. A hydromulch/fertilizer
treatment also was applied to a section of each of
the slopes. Adjacent to these sections, 2-1/2 inch-
es of mature yard trimmings compost was spread.
On the 2 to 1 slope, a small amount of fertilizer
was also applied, while the 3 to 1 slope was left
unfertilized. Fescue grass seed was added and
covered with a thin layer of compost to conceal the
seed from birds.
-Rain
Field Water
Layer of Compost
Compost Berm
On steep slopes, berms (mounds) of compost at the top or bottom of slopes can ,^^^^,
be used to slow the velocity of water and provide additional protection for receiving waters.
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Photos courtesy of The Federal Highway Administration, Office of
Environment &• Planning, and Federal Lands Highway Program
Embankment adjacent to new intersection. Top left photo
shows hillside before seeding. Photo at right shows grass
cover. Compost-treated plot displays darker green color and
thicker growth.
Results of the project revealed that compost used
alone produced better results than either of the
areas treated with hydromulch or the area treated
with compost and fertilizer. While the areas with
the hydromulch/fertilizer combination showed quick
initial vegetative growth, the areas treated with only
compost persevered within 6 months, out-perform-
ing the traditional method by establishing a thick,
healthy vegetative cover. The growth in the com-
post/fertilizer plot was superior to that found in the
hydromulch/fertilizer plots. A possible explanation
for compost alone out-performing the area treated
with compost and fertilizer is that chemical fertiliz-
ers often increase soil salinity, which in turn could
negatively affect the beneficial micro-organisms in
compost and inhibit the establishment of healthy
grasses.
Using Compost to Remediate
Turf Grasses
Hroviding safe, uniform playing surfaces
for recreational activities, such as golf,
football, soccer, and other field sports,
requires intensive turf management.
Recreational turf grasses are subjected to
extensive wear and tear, making them difficult to
manage and highly susceptible to turf diseases,
pests, and soil compaction. To address these prob-
lems, turf managers traditionally use a combination
of fertilizers, pesticides, fungicides, and aeration
techniques that usually result in high costs and
potential for negative environmental impacts.
Some turf managers are now using compost to
replace peat moss in their topdressing applications
based on its proven success in suppressing plant
disease. Compost, when properly formulated,
unlike peat moss, is teeming with nutrients and
micro-organisms that stimulate turf establishment
and increase its resistance to common turf diseases,
such as snow mold, brown patch, and dollar spot.
For example, after 3 years of using compost as a
topdressing, the Country Club of Rochester, New
York, has nearly eliminated the need for fungicide
applications for such diseases.
Alleviating Soil Compaction
Soil compaction is another persistent landscape
management problem, particularly in areas of heavy
traffic, such as parks, zoos, golf courses, and athlet-
ic playing fields. Compacted soil impedes healthy
turf establishment by inhibiting the movement of
air, water, and nutrients within the soil. Bare soil,
weeds, increased runoff, and puddling after heavy
rains are the most obvious signs of a soil com-
paction problem.
Traditional methods for alleviating soil com-
paction—aeration, reseeding, or complete resod-
ding—are labor-intensive and expensive, and
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> What Are the Benefits of Using
Compost?
Soil Enrichment:
• Adds organic bulk and humus to regenerate
poor soils.
• Helps suppress plant diseases and pests.
• Increases soil nutrient content and water
retention in both clay and sandy soils.
• Restores soil structure after reduction of
natural soil microbes by chemical fertilizer.
• Reduces or eliminates the need for fertilizer.
• Combats specific soil, water, and air problems.
Pollution Remediation:
• Absorbs odors and degrades volatile organic
compounds.
• Binds heavy metals and prevents them from
migrating to water resources or being
absorbed by plants.
• Degrades, and in some cases, completely elim-
inates wood preservatives, petroleum products,
pesticides, and both chlorinated and nonchlori-
nated hydrocarbons in contaminated soils.
Pollution Prevention:
• Avoids methane production and leachate
formation in landfills by diverting organics for
composting.
• Prevents pollutants in stormwater runoff from
reaching water resources.
• Prevents erosion and silting on embankments
parallel to creeks, lakes, and rivers.
• Prevents erosion and turf loss on roadsides,
hillsides, playing fields, and golf courses.
Economic Benefits:
• Results in significant cost savings by reducing
the need for water, fertilizers, and pesticides.
• Produces a marketable commodity and a
low-cost alternative to standard landfill cover
and artificial soil amendments.
• Extends municipal landfill life by diverting
organic materials from the waste stream.
• Provides a less costly alternative to
conventional bioremediation techniques.
provide only short-term solutions. Some turf man-
agers are starting to use compost and compost
amended with bulking agents, such as aged
crumb rubber from used tires or wood chips, as
cost-effective alternatives. Incorporating tailor-
made composts into compacted soils improves
root penetration and turf establishment, increases
water absorption and drainage, and enhances
resistance to pests and disease. Using tailored
compost can also significantly reduce the costs
associated with turf management. Research con-
ducted at a U.S. Air Force golf course in Colorado
Springs, Colorado, for example, indicated that turf
grown in areas improved with tailored compost
required up to 30 percent less water, fertilizer,
and pesticides than turf treated conventionally.
I Greening the Links
The U.S. Army Golf Course Operations Division
at Fort George Meade, Maryland, and the U.S.
Environmental Protection Agency began a 3-year
pilot demonstration in 1995 to determine the effec-
tiveness of compost amended with crumb rubber
in alleviating soil compaction, erosion, and turf dis-
ease problems. The golf course superintendent esti-
mates that using compost technology would save
nearly $50,000 a year in maintenance costs.
Photo courtesy of U.S. Army, Fort George Meade, Maryland
At the U.S. Army Golf Course at Fort George Meade,
Maryland, erosion can clearly be seen on the untreated right
side of the path, while rubber amended compost is helping
keep erosion in check on the left.
-------
Mature yard trimmings compost amended with
crumb rubber was incorporated into compacted
soils at 13 different locations around the two golf
courses. Many of the selected sites included areas
adjacent to, or at the end of golf cart paths, on
slopes surrounding greens, or in tee boxes. These
sites were selected because of their susceptibility
to compaction and erosion caused by heavy traffic
and water runoff. The compost mixture was tilled
into the soil to a depth of about 3 to 5 inches and
then uniformly seeded. To act as a control, one of
the plots was amended only with crumb rubber.
In the first year of the pilot, course operators report-
ed that healthy, green turf grass took hold at most of
the sites, with no signs of compaction or erosion.
Results were particularly impressive in eroded ditch-
es along cart paths. The areas treated with the com-
post mixture showed full growth of turf grasses and
total abatement of erosion, whereas the plot amend-
ed only with crumb rubber showed few signs of
improvement.
Using amended compost
can significantly reduce
the costs associated with
turf management
Using Compost in
Landscaping Activities
upplies of high-quality, low-cost top-
soil are declining, particularly in urban
areas where the demand is greatest.
Compost is, therefore, becoming partic-
ularly important in applications requir-
ing large amounts of topsoil. Increasingly,
compost is being used as an alternative to natural
topsoil in new construction, landscape renova-
tions, and container gardens. Using compost in
these types of applications is not only less
expensive than purchasing topsoil, but it can
often produce better results when trying to estab-
lish a healthy vegetative cover.
After a lawn or garden has been established,
maintaining it can be a challenge for both home
gardeners and commercial landscape contractors.
While aeration, topdressing, and chemical fertil-
izer applications are some of the techniques com-
monly employed in landscaping applications,
compost can be a successful alternative. When
used as a topdressing, or periodically tilled into
the soil, compost can stimulate plant growth,
reduce pests and plant infestation, and improve
soil structure.
Compost is also an effective landscaping
mulch. Placed over the roots of plants, compost
mulch conserves water and stabilizes soil tem-
peratures. In addition, compost mulch keeps
plants healthy by controlling weeds, providing a
slow release of nutrients, and preventing soil loss
through erosion. Landscapers and gardeners also
use compost as mulch because its dark, rich
color accents the vibrant colors of flowering
plants.
-------
I Landscaping Constitution Gardens
In 1973, the U.S. National Park Service used a
compost mixture made of digested sewage
sludge, wood chips, leaf mold, and a small
amount of topsoil to transform a badly compacted
40-acre tract of land located in Washington, DC,
into a landscaped park. This project is one of the
earliest successful large-scale landscaping appli-
cations using compost.
The original plans for the park renovations
included planting azalea beds and thousands of
annuals around a 6-acre lake. However, the site
assessment revealed that the soil was almost as
hard as concrete, with little pore space for plant
roots and for water infiltration. The soil was too
low in nutrients for healthy plant growth. In addi-
tion, the water table was high, causing flooding
and root rot in existing plants.
Park Service staff spread over 9,400 cubic yards
of the compost mixture over the site. Fertilizer,
woodchips, and seed were added, and the soil
was tilled to a depth of 2 feet. Impressed by the
hardiness and beauty of a stand of hardwood
trees along the area's western edge, Park Service
staff decided to plant several varieties of native
trees rather than the planned azalea beds. Data
taken 3 years after the project ended indicated
that most of the nearly 2,000 trees initially planted
had flourished in the park.
Photo courtesy of U.S. National Park Service
More than 9,400 cubic yards of compost was used to
remediate heavily compacted soil at Constitution Gardens
in Washington, DC.
Photo courtesy of U.S. National Park Service
Three years after compost was applied, the vegetation at
Constitution Gardens flourishes.
The compost use in this project not only
improved the quality of the existing soil, but also
saved taxpayers over $200,000. Park Service staff
also reviewed other options for remediating the
soil at the park, including the purchase of topsoil
to spread over the existing poor soil. If the Park
Service staff had chosen to use topsoil, the cost of
the project would have doubled.
I Using Compost for Rooftop Gardens
Several years ago, officials at Pace School in
Pittsburgh, Pennsylvania, proposed building a
playground and garden for their students. They
soon discovered, however, that the only space
available was on the school's roof, so they
designed a unique rooftop garden.
Plans for the garden included building large,
6-foot deep planters. Before the planters were
constructed, several important factors had to be
taken into consideration. The planter mix used had
to be light enough for the roof to withstand the
weight, yet dense enough to prevent rapid evapo-
ration caused by the wind and summer heat. In
addition, the planter mix had to be able to endure
freezing temperatures in winter, and provide ade-
quate drainage to prevent the planters from over-
flowing during rainstorms.
-------
Photo courtesy of AgRecycle Inc.
Tailor-made compost was the key to success for the rooftop garden at Pace School in Pittsburgh,
Pennsylvania.
To meet these special needs, the school decided
to use a tailor-made mature compost blend,
chosen because its bulk density is much lighter
than soil-based mixes. The compost mix is also
extremely absorbent, maintains good drainage,
and protects plant roots from climatic fluctuations.
A local compost producer tailor-made a mature
yard trimmings compost mixture to meet the
project's specifications. A layer of polystyrene
packaging peanuts was placed in the bottom of
each planter box to enhance drainage, and a
5-foot layer of the compost mixture was placed on
top.
Four years after the project began, the school
continues to use its rooftop garden for a number
of activities, including teaching science classes
and gardening methods. The compost has per-
formed very well as a growing medium and contin-
ues to produce beautiful, healthy plants that both
the students and teachers can enjoy.
I Using Compost in Landscape Maintenance
Each year, millions of people visit Point State
Park in Pittsburgh, Pennsylvania. Heavy traffic
and 12 continuous years of chemical fertilizer
applications caused the park's grassy areas to
become increasingly compacted, eroded, and
depleted of vital nutrients.
After considering several options, park officials
decided to aerate the grassy areas and apply a
special blend of mature yard trimmings compost
and fire calcined clay. This compost mixture was
designed to alleviate compaction, add nutrients to
the soil, and to improve water-holding capacity.
Workers spread a 1/4-inch topdressing of the
compost mixture and then uniformly applied grass
seed. Soon after the compost was applied, park
officials noted that the turf was healthier and that
the soil no longer exhibited signs of compaction.
-------
References
Cazenas, P. and R.E. Green. 1997. Erosion preven-
tion on steep enbankments by mature yard trim-
mings compost compared to hydromulch.
Washington. (In manuscript).
Castagnero, C. 1996. Conversation with Dr. R.E.
Green. Establishment of Pace School Rooftop
Garden with the use of tailored, mature compost.
Pittsburgh.
—. 1996. Conversation with Dr. R.E. Green.
The use of mature compost in state park landscape
maintenance. Pittsburgh.
Federal Highway Administration. 1996. Standard
Specifications For Construction of Roads and
Bridges on Federal Highway Projects, U.S.
Department of Transportation. FP-96, Sec. 713,
p.719.
Lincoln, T. Rebound—the New Product Turf
Managers Dream About, Jai Tire Industries. Denver.
Nelson, E.B. 1992. The biological control of turf-
grass diseases. Golf Course Management.
April: 78-90.
Patterson, J. 1994. The successful remediation of
severely-compacted soil at the U.S. Constitution
Gardens. Paper presented at a workshop in
Washington.
Wilkinson, J.F. 1992. Applying compost to the golf
course. Golf Course Management. April: 78-90.
For More Information
This fact sheet and other information about solid waste
issues are available in electronic format on the Internet at
http://www.epa.gov/osw; select "Reduce, Reuse, Recycle."
Use Internet e-mail to order paper copies of documents.
Include the requestor's name and mailing address in all
orders. Address e-mail to: rcra-docket@epamail.epa.gov.
Paper copies also may be ordered by calling the RCRA
Hotline. Callers within the Washington Metropolitan Area
must dial 703 412-9810 or TDD 703 412-3323 (hearing
impaired). Long-distance callers may call 800 424-9346 or
TDD 800 553-7672. The RCRA Hotline operates weekdays,
9 a.m. to 6 p.m.
Mail written document requests to the RCRA Information
Center (5305W), U.S. EPA, 401 M Street, SW., Washington,
DC 20460.
SEPA
United States
Environmental Protection Agency
(5306W)
Washington, DC 20460
Official Business
Penalty for Private Use
$300
-------
Innovative Uses of Compost
Disease Control for Plants
and Animals
ompost technology is a valuable tool already being used to
increase yields by farmers interested in sustainable agriculture.
Now, professional growers are discovering that compost-
enriched soil can also help suppress diseases and ward off
pests. These beneficial uses of compost can help growers save money,
reduce their use of pesticides, and conserve natural resources. In the poul-
try industry, composting has also become a cost-effective method of mortal-
ity management. It destroys disease organisms and creates a nutrient-rich
product that can be used or sold.
Plant Disease Control
ach year, more than 10 percent of the vegetables planted in the
United States are lost to root rot alone, according to researchers
at the University of Florida's Tropical Research and Education
Center. Additional crop losses are caused by other soilborne
plant pathogens, such as the micro-organisms that cause ashy stem blight
and chili pepper wilt. Compost can help control plant disease and reduce
crop losses. Disease control with compost has been attributed to four possi-
ble mechanisms: (1) successful competition for nutrients by beneficial
micro-organisms; (2) antibiotic production by beneficial micro-organisms;
(3) successful predation against pathogens by beneficial micro-organisms;
and (4) activation of disease-resistant genes in plants by composts.
Scientists have enhanced the natural ability of compost to suppress
diseases by enriching it with specific disease-fighting micro-organisms or
other amendments. This amended or "tailored" compost can then be
applied to crops infected by known diseases. Research has shown that tai-
lored compost significantly reduced or replaced the application of pesti-
cides, fungicides, and nematicides—which could adversely affect water
resources, food safety, and worker safety.
) Printed on paper that contains at least 20 percent postconsumer fiber.
-------
The use of tailored compost can also be more
cost-effective than chemical soil treatments, such as
methyl bromide. Soil treated with compost retains
irrigation water better, which lowers water costs.
Chemicals also must be applied more often than
compost. In addition, some chemicals have re-entry
requirements that prohibit workers from entering a
field immediately after chemicals have been applied,
reducing worker productivity.
Compost Impedes Pythium
Root Rot
Dr. Harry Hoitink of The Ohio State University,
has conducted compelling research on compost's
effects on plants afflicted with Pythium root rot. As
the photo below illustrates, the application of tai-
lored compost had a dramatically positive effect on
plant growth and impeded the spread of the disease.
Photo courtesy of Dr. Harry Hoitink, University of Ohio
The plant on the right was treated with compost. The plant on
the left was not and suffered the effects o/Pythium root rot.
Dr. Hoitink views the disease-suppressive charac-
teristics of compost as a reason to consider widen-
ing compost applications, "Those who believe
composting is not practical for large acreages would
find Brazil interesting. I visited a sugar cane farm of
some 150,000 acres where the bagasse [stalks left
after harvest] was composted and applied back on
the land. Every acre got a treatment once every 5
years with 15 percent increases in yield. Some of
that increase is apparently due to a suppression of
disease organisms."
Compost Combats Chili Wilt
Researchers from New Mexico State University
applied a compost made from municipal wastewater
sludge and yard trimmings to chili crops in a field
known to be infested with Phytophthora root rot, or
chili wilt. Four different quantities of compost were
applied: 10, 20, 30, and 50 tons per acre. Another
section of the field, where no compost was applied,
was used as a control area. Data collected included
damping off disease effects, plant height, chili wilt
infection, and yields.
The study showed that salt content in compost
plays an integral role in suppressing diseases and
increasing crop yields. The 10-ton and 20-ton com-
post applications provided the greatest suppression
of chili wilt and the highest yields. The 50-ton treat-
ment resulted in the poorest yields. The control
acreage and the 30-ton application also produced
poor yields. The losses in the 30- and 50-ton
acreages were attributed to high salt concentrations
in the compost, which weakened the plants and
made them more susceptible to chili wilt. For opti-
mal results, therefore, salt concentrations in compost
should be measured and application rates adjusted
accordingly. Plant salt sensitivity requires a tailored
compost controlled for salt concentration.
Compost Abates Ashy Stem
Blight and Root Rot
University of Florida researchers tested the effects
of Agrisoil (compost made of mixed municipal solid
waste) and Daorganite (a heat-treated biosolids mix),
on test plots in a field in Homestead, Florida. The
Agrisoil compost was applied at rates of 36 tons per
acre and 72 tons per acre, and the Daorganite sludge
was applied at rates of 0.67 tons per acre and 1.33
tons per acre. Sections of the field also were left
-------
untreated as a control. Six weeks after the materials
were incorporated into the soil, researchers planted
bush beans throughout the field. A second crop,
black-eyed peas, was planted following the bean
harvest, and Agrisoil compost and Daorganite were
applied at the same rates as in the bush bean project.
The field was also fertilized according to accepted
local agricultural practices.
The health and yields of the bush bean crops
were significantly improved by compost. Beans
grown in the Agrisoil compost were larger and
healthier. Yields from the 36 and 72 tons per acre
application areas were both 25 percent higher than
control area yields. Beans grown in the Daorganite
mix showed low yields similar to those grown in the
control areas. In addition, ashy stem blight severely
affected beans grown in both the control and
Daorganite-treated areas, but not the plots with
Agrisoil compost.
The health and yields of the black-eyed pea crops
grown in compost were also significantly improved.
These crops had greener foliage and were larger than
those grown in the control or Daorganite-treated
plots. Yields from the compost-enriched areas were
more than double the control yields in the 72 tons
per acre application sections and also significantly
higher in the 36 tons per acre sections. By compari-
son, yields in the Daorganite-treated areas were only
slightly higher or comparable to those in the control
sections. Rhizoctonia root rot severely affected plants
in the Daorganite-treated and control areas, but the
disease was considerably less prevalent in the com-
post-enriched areas.
In this particular study, yields and disease infec-
tion proved to be directly related in both the bean
and pea crops. Mature Agrisoil compost was more
effective at disease suppression than the Daorganite
heat-treated biosolids mix. Thus, yields were uni-
formly higher in the Agrisoil-treated areas than in the
Daorganite-treated and control areas.
Mortality Composting
More than 7.3 billion chickens, ducks, and
turkeys are raised for commercial sale in the
United States each year, according to U.S.
Department of Agriculture's National Agricultural
Statistics Service. About 37 million birds (18-25
percent) die from disease or other natural causes
before they are marketable. As more poultry is
consumed, these numbers are expected to climb.
Composting is a viable and cost-effective option
for disposing of poultry mortalities as compared to
incineration or burial. Pathogens in poultry carcasses
are destroyed during composting by the high temper-
atures (130-155 degrees Fahrenheit) inherent in the
process.
During composting, various odor control tech-
niques can be used. As a result, this type of com-
post is not only safe for crop application, but it
also can be safely sold by farmers. In fact, selling
excess compost could even be a source of addi-
tional income for farmers. Markets for high-quality
compost include professional growers (such as
horticultural greenhouses and nurseries), home-
owners, turf growers, and crop farmers (such as
corn and wheat farmers). Professional growers
alone purchase $250 million per year in compost
products.
Pest Control
ompost also can eradicate some types of
pests, such as parasitic nematode
(worm) infections, in addition to its use
in controlling disease. Specially formu-
lated (tailored) compost can include chemicals that
actually kill nematodes or prevent their eggs from
hatching. Most types of compost help control para-
sitic nematodes by providing nutrients to the soil,
which encourage the growth of fungi and other
organisms, which, in turn, compete with or destroy
nematodes. Compost also contributes to plants'
basic health, making them less susceptible to pests.
-------
Compost's ability to halt soil nematode invasion
was identified by the staff of Dr. Herbert Bryan of the
University of Florida. While studying plant response
to different compost applications and irrigation rates,
the staff, who had a background in nematology,
noted the unexpected results while conducting rou-
tine observations. "Where compost was used, even
without a fumigant, there was a significant reduction
in rootknot nematodes," said Dr. Bryan.
Later research by Dr. Tom Obreza, a soil and
water scientist at Southwest Florida Research and
Education Center, turned up similar results. Dr.
Obreza's experiment consisted of growing tomatoes
in composts from several different sources and com-
paring them to control plots treated with the usual
Biopesticides (Tailored Compost)
Biopesticides are becoming effective alternatives
to chemical pesticides. Biopesticides are made by
adding controlled amounts of pest-fighting micro-
organisms to compost, which results in "tailored"
compost with a specific pesticidal capability. Biopesti-
cides must be registered with the U.S. Environmental
Protection Agency (EPA) and undergo the same
level of testing as chemical pesticides to determine
their effectiveness and their safety for public health
and the environment. Although one type of tailored
compost that is inoculated by a patented process is
already registered as a biopesticide with EPA, many
more are expected to follow suit.
&EPA
United States
Environmental Protection Agency
(5306W)
Washington, DC 20460
Official Business
Penalty for Private Use
$300
fertilizers. Dr. Obreza found no disease problems in
any of the plots except one. Dr. Obreza noted, "We
had a little invasion of rootknot nematode in one
corner of the field. The infection was evident in the
plants right up to the compost treated plots and
stopped right there. The difference was as plain as
night and day."
References
Hoitink, H.A.J., and P.C. Fahy. 1986. Basics for the con-
trol of soil-borne plant pathogens with composts.
Annual Review of Phytopathology 24: 93-114.
Hoitink, H.A.J., Y. Inbar, and M. J. Boehrn. 1991.
Compost can suppress soil-borne diseases in container
media. American Nurseryman. September: 91-94.
Hoitink, H.A.J. 1990. Production of disease suppressive
compost and container media, and microorganisms
culture for use therein. U.S. Patent 4,960,348.
Marvil, J., J. Pinochet, and R. Rodriguez-Kabana. 1997.
Agricultural and municipal composts residues for con-
trol of root-knot nematodes in tomato and peppers.
Compost and Utilization 5(1): 6-15.
For More Information
This fact sheet and other information about solid waste issues
are available in electronic format on the Internet at
http://www.epa.gov/osw; select "Reduce, Reuse, Recycle." Use
Internet e-mail to order paper copies of documents. Include the
requestor's name and mailing address in all orders. Address e-
mail to: rcra-docket@epamail.epa.gov.
Paper copies also may be ordered by calling the RCRA Hotline.
Callers within the Washington Metropolitan Area must dial
703 412-9810 or TDD 703 412-3323 (hearing impaired). Long-
distance callers may call 800 424-9346 or TDD 800 553-7672.
The RCRA Hotline operates weekdays, 9 a.m. to 6 p.m.
Mail written document requests to the RCRA Information
Center (5305W), U.S. EPA, 401 M Street, SW., Washington, DC
20460.
-------
Innovative Uses of Compost
Composting of Soils
Contaminated by Explosives
Introduction
oil at more than 30 munitions sites across the United States is
contaminated with explosives. The U.S. military has discovered
that the composting process, and the use of finished (mature,
cured) compost can effectively remediate munitions-contaminat-
ed soils. To incorporate such soil into the composting process, the soil is
excavated and mixed with other feedstocks. The end-product is a contami-
nant-free soil, containing nutrient-rich humus that can enhance landscap-
ing and horticultural applications. Composting costs considerably less
than soil excavation and incineration, the traditional method used for
these cleanups.
The Umatilla Army Depot in Hermiston, Oregon, has successfully used
composting to convert 15,000 tons of contaminated soil into safe soil con-
taining humus. By using composting instead of incineration, Umatilla
saved approximately $2.6 million. Clean-up goals for Umatilla were estab-
lished at concentrations of less than 30 milligrams per kilogram for 2,4,6-
Trinitrotoluene (TNT) and Royal Demolition Explosives (RDX). The project
exceeded these expectations by achieving nondetectable levels of explo-
sives. Contaminant byproducts were either destroyed or permanently
bound to soil or humus.
The success at Umatilla indicates that composting of explosive-contam-
inated soil is a cost-effective and environmentally sound clean-up method.
Millions of dollars could be saved if the composting process were used
rather than conventional incineration to clean up contaminated soils at
these and other military operations in the United States. Other sites using
composting for explosives include the U.S. Naval Submarine Base in
Bangor, Washington; the Navy Surface Warfare Center in Crane, Indiana;
and the Sierra Army Depot in Herlong, California.
) Printed on paper that contains at least 20 percent postconsumer fiber.
-------
How Contamination Occurred
at Umatilla
ver a 15-year period during the 1950s
and 1960s, workers at Umatilla used
water and steam to clean TNT, RDX,
and other explosives out of decom-
missioned 500- and 750-pound bombs. In the
process of cleaning these bombs, more than 80
million gallons of explosive-contaminated "pink
water" (named for its characteristic color) were
washed into two 10,000 square-foot lagoons.
When the water evaporated, workers excavated
and transported the residual solids to another area
and burned them. While the use of evaporative
ponds was the accepted wastewater disposal tech-
nique at the time, it caused an unforeseen prob-
lem. Contaminants seeped into the soil and the
ground water underlying the evaporation lagoons.
In 1987, Umatilla was put on the Superfund list
for hazardous waste cleanup because of TNT and
RDX levels of 4,800 parts per million.
Photo courtesy of Bioremediation Service, Inc.
Workers, using highly specialized mixing equipment, turn steaming windrows of soil
amendments mixed with explosive-contaminated soil from the Umatilla Army Depot.
How Composting of Explosive-
Contaminated Soils Works
hrough the process in which compost is
made, naturally occurring micro-organ-
isms break down the explosive contami-
nants in the soil. Using the
contaminants as "food," the micro-organisms
convert them into harmless substances consisting
primarily of water, carbon dioxide, and salts. In
addition to this food source, micro-organisms
require nutrients, such as carbon, nitrogen, phos-
phorous, and potassium, in order to thrive,
digest, and reproduce. To provide these nutrients
in sufficient quantities, soil amendments, such as
manure and potato waste, were added to the con-
taminated soil at Umatilla.
Before beginning work at Umatilla, extensive
tests were performed to determine the best mix-
ture of contaminated soil and soil amendments to
be used in the composting process. Numerous
factors influence what mix of these ingredients
provides micro-organisms
with the optimum environ-
ment in which to live. The
most important factor is the
carbon to nitrogen ratio.
Other factors influencing the
choice of soil amendments
include moisture, pH,
degradability, percentage of
organic matter, and availabil-
ity of specific soil amend-
ments. The composting
feedstocks used at Umatilla
were 30 percent contaminat-
ed soil, 21 percent cattle
manure, 18 percent sawdust,
18 percent alfalfa, 10 percent
-------
potato waste, and 3 percent chicken manure. In
other geographical areas, substitutions may be
made depending on the cost and availability of
ingredients.
Large, temporary mobile buildings were con-
structed to control fumes and ensure optimum
conditions for the composting process. The mix-
ture of contaminated soil and soil amendments
was placed into windrows. Workers, using highly
specialized mixing equipment, turned these
steaming piles three times daily to: (1) ensure that
the compost received sufficient oxygen; (2) release
trapped heat, water vapor, and gases; and (3) to
break up clumps. Treatment time for a 2,700-
cubic-yard batch of soil was 10 to 12 days.
Benefits of Composting
Explosive-Contaminated Soils
omposting of explosive-contaminated
soils has significant economic and
environmental benefits. At Umatilla,
composting saved an estimated $2.6
million over incineration for cleanup of the entire
site. Clean-up costs at Umatilla were estimated to
be $527 per ton for combustion and $351 per ton
for composting, resulting in a savings of $176 per
ton.
In addition, the end-product of the composting
process, humus-rich soil, generally sells for at least
$10 per ton, resulting in potential revenues of
$150,000. Together, the savings ($2.6 million) and
potential revenue ($150,000) from using the com-
posting process to remediate explosive-contaminat-
ed soil could be $2.75 million. By contrast, the
end-product of combustion has limited commercial
value, and represents minimal potential revenue.
Combustion Versus Composting at Umatilla Army Depot
COST
Total Clean-up Cost for 15,000 Tons
of Contaminated Soil*
BENEFIT
Value Added from Sale of 15,000
Tons of Treated Soil
$8,000,000
7,000,000
6,000,000
5,000,000
4,000,000
3,000,000
2,000,000
1 ,000,000
0
-
$7,905,000
$5,305,000
!: Saves !
$2.6
Million
I
Combustion Composting
$150,000
120,000
90,000
60,000
30,000
0
$0
$150,000
Thousand
Combustion Composting
Savings and Revenue From Composting $2,600,000 + $150,000 = $2,750,000
Based on information contained in "First Production-Level Bioremediation of Explosives-Contaminated
Soil in the U. S." by David D, Emery and Patrick C. Faessler, Bioremediation Service, Inc.
-------
Photo courtesy of Bioremediation Service, Inc.
Large, temporary buildings controlled fumes and ensured
optimum conditions for the composting of explosive-
contaminated soil at the Umatilla Army Depot.
The U.S. Army Corps of Engineers has estimat-
ed that if composting were used to clean up the
remaining U.S. munitions sites, $200 million
could be saved.
While incinerators use large quantities of fossil
fuel, a nonrenewable resource, only a small amount
of fuel is needed for the machines that stir compost-
ing windrows. Incinerating soil at hazardous materi-
al disposal facilities results in ash that must be
handled and disposed of as hazardous residue. By
contrast, composting produces a nutrient-rich prod-
uct comparable to an enriched top soil that can be
used in landscaping and agricultural applications.
In fact, tests on plants grown in remediated soil
showed no toxic effects from the contaminants and
that the contaminants were no longer present.
According to Dr. Michael Cole, an expert in the
v=,EPA
United States
Environmental Protection Agency
(5306W)
Washington, DC 20460
Official Business
Penalty for Private Use
$300
degradation of organic contaminants in soil,
composting, more than any other soil cleanup
technique, results in an enriched soil end-product
and restores the earth to a better condition than
before it was contaminated.
References
Emery, D.D., and P.C. Faessler. 1996. First produc-
tion-level bioremediation of explosives-contaminat-
ed soil in the U.S..
Weston, R.F., Inc. 1993. Windrow composting
demonstration for explosives-contaminated soils at
the Umatilla Depot Activity. Hermiston. Document
No: CETHA-TS-CR-93043.
Williams, R.T., and P.J. Marks. Optimization of
composting of explosives-contaminated soil.
Washington: U.S. Army Corps of Engineers.
CETHA-TS-CR-91053.
Williams, R.T., P.S. Zieganfuss, and W.E. Sisk.
1992. Composting of explosives and propellant
contaminated soils under thermophilic and
mesophilic conditions. Journal of Industrial
Microbiology. 9:137-144.
For More Information
This fact sheet and other information about solid waste issues
are available in electronic format on the Internet at
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Use Internet e-mail to order paper copies of documents.
Include the requestor's name and mailing address in all
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Paper copies also may be ordered by calling the RCRA
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must dial 703 412-9810 or TDD 703 412-3323 (hearing
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TDD 800 553-7672. The RCRA Hotline operates weekdays,
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Center (5305W), U.S. EPA, 401 M Street, SW., Washington,
DC 20460.
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Innovative Uses of Compost
Reforestation, Wetlands
Restoration, and Habitat
Revitalization
he native plants that inhabit America's countrysides—from the
sunflowers on the Great Plains to the oak seedlings in the
Appalachians—are a source of great beauty. But the plants within
a habitat contribute much more to their surroundings than mere
beauty. They provide a vital food source for many members of the habitat.
They enrich the air through the gases they produce and minerals they
exchange. Even when plants die, they continue to support grasses, flow-
ers, and trees by becoming part of the humus, or organic material in soil,
that is so vital to living plants.
Unfortunately, much of the organic material in the soils in the United
States has been stripped by natural and man-made stresses such as ero-
sion, flooding, and logging. But barren soils can be restored with the help
of compost. Compost adds the missing infrastructure, humus, and nutri-
ents that plants need to re-establish themselves in decimated areas.
Organic matter in the soils of wetlands in the United States has
decreased steadily over the last three centuries. According to Dr. Donald
Hey, an expert in flood plain management, over 100 million acres of U.S.
wetlands have been drained, and our watersheds now contain only about
half the amount of organic matter they contained in the 17th century. As a
result, annual floods have worsened, ground water quality has deteriorat-
ed, and wildlife diversity has declined. Compost, with its high organic
content, can absorb up to four times its weight in water and can replace
essential organic material in wetlands.
In addition to wetlands restoration, compost also can help restore
forests and revitalize habitats. Compost can play an important part in
reforestation efforts by providing an excellent growing medium for young
seedlings. In the same way, compost can help to revegetate barren habi-
tats, providing the necessary sustenance for native wildlife populations.
By enhancing the chemical and mineral properties of soil, compost facili-
tates native plant growth, which provides food for native and endangered
animal populations.
) Printed on paper that contains at least 20 percent postconsumer fiber.
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Reforestation:
Nantahela National Forest and
the Qualla Cherokee Reservation
nn 1996, the U.S. Forest Service, Bureau of
Indian Affairs, Cherokee Tribal Council, and
the U.S. Environmental Protection Agency
(EPA) launched a 3-year, joint study
(1995-1998) to test the effectiveness of straw
• (fj
! I
. w
Photo courtesy of U.S. Forest Service
U.S. Forest Rangers and Cherokee workers
cleared plots for the compost study.
compared to three different kinds of composts in
stimulating tree seedling growth and reducing soil
erosion. The three composts, made from yard
trimmings, municipal waste water sludge
(biosolids), and municipal solid waste (MSW),
were used as a 2-inch mulch on white pine soft-
wood, chestnut oak, and Chinese chestnut hard-
wood seedlings.
The project was carried out at three different
sites within the Cheoah Ranger District,
Nantahela Forest and the adjoining Qualla
Cherokee Reservation at Cherokee, North
Carolina. U.S. Forest Rangers and Cherokee work-
ers cleared and planted the plots for this study.
The study sites were chosen because they con-
tained compacted, eroded areas or disturbed steep
slopes. Each of the three composts and the straw
were tested on two plots each, and the seedling
types were grown on each plot.
After 20 months, results showed that height,
diameter, and survival rates for seedlings planted
in the composted test plots exceeded the straw
test plots. In addition, volunteer revegetation by
herbaceous plants was remarkable in the com-
posted plots. After 30 months, erosion was evi-
dent in the straw plots but not in the composted
plots.
Photos courtesy of
U.S. Forest Service
Seedlings planted in compost mulch flourish and show
greater growth than seedlings planted in straw mulch.
Average Seedling Diameter
(inches after 20 months)
0.05
White Pine
Chestnut Oak
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year
Habitat Restoration:
Patuxent Wildlife Research
Center Project
r. Matthew C. Perry, a habitat manage-
ment scientist at the Patuxent Wildlife
Research Center in Maryland, in coop-
eration with the EPA, is leading a 2-
ly (1996-1998) to show the value of using
composts to restore wildlife habitats. Past military
and farming operations at Patuxent degraded
native plant populations, resulting in a serious
decline of many animal populations in the area.
The aim of the new study is to revegetate a 4.8-
acre site with native plants in an effort to restore
the food sources for indigenous wildlife popula-
tions, including songbirds, game species, small
mammals, amphibians, reptiles, and insects.
The study is comparing the effectiveness of
two compost materials, one made from municipal
wastewater sludge (biosolids), and the other made
from yard debris. These two soil treatments, with
two types of controls, were randomly assigned to
eight plots and replicated twice. Control plots
received no compost and were of two types: one
that was planted with a hand-collected mixture of
native grasses and legumes and one that was not
planted. Plots with compost were also planted
with the native plant mixture.
Preliminary results, in the late fall of 1996,
indicated the greatest revegetation of plots
occurred in areas treated with compost made
from yard debris; but, all of the plots with com-
post had superior growth compared to the control
plots.
Piles of compost await spreading on a degraded area of
Patuxent Wildlife Research Center.
Regaining Wetlands:
Clean Washington Center Project
t a site in Everett, Washington, the
Clean Washington Center sponsored a
2-year project, from 1994-1996, to test
two types of compost in the restora-
tion of damaged wetlands. The restoration site
consisted of two large wetlands joined by a cul-
vert 550 feet long and 18 inches deep. Decades
ago, a sawmill sat in the sandy area between the
wetlands. Once the mill was torn down, the area
was left relatively barren, which made the rail-
road tracks and bike path adjacent to the upper
wetland prone to flooding. The project utilized
compost extensively to keep the adjacent railroad
tracks and bike path from flooding.
The project's construction team deposited a
yard debris compost and a mixed compost made
of biosolids and yard debris into 14 separate test
plots. A control plot containing no compost was
also developed. Workers then introduced a selec-
tion of indigenous wetland plant species into
each plot and monitored the growth of the plants
every six months, through 1996.
The project showed that the compost enriched
soils closely mimicked the natural wetland sub-
strate. In addition, the plants in both compost test
plots exhibited 20 percent more growth, and a 10
to 15 percent higher survival rate than the control
plots. The site also handled the flow of 1996's
heavy winter rains quite well, and the railroad
tracks and bike path did not flood.
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Photo courtesy of the Clean Washington Center
Damaged wetlands near railroad tracks in Everett, Washington,
flooded the tracks constantly. Restoration with compost prevent-
ed flooding and helped support the native beaver population.
Des Plaines River Flood Plain
r. Donald Hey, an expert in flood plain
management, tested the value of using
compost to restore 37 acres of wetlands
in a project he conducted on the banks
of the Des Plaines River in northern Illinois. He
and his staff used compost to encourage the
growth of native plants in four marshes. One por-
tion of the marshes, functioning as a control, was
not treated with compost.
Positive results were observed within 2 years of
incorporating compost into the soil along the
river. Flood storage of the area—the ability of the
soil to absorb and contain the excess water from
floods—had improved dramatically compared to
the control area. River water quality also
improved significantly, with reduced nitrogen
values and fewer suspended solids in rehabilitat-
ed areas of the river. In fact, the revitalized soil
and plant life removed 90 to 95 percent of the
nitrogen and suspended solids from the water.
References
Bonnette, J., and R.E. Green. 1995. Report on the effec-
tiveness of composts in stimulating tree seedling
growth and reducing soil erosion. Clemson: U.S.
Southeaster Forest Service.
Lynch, Mary E. 1995. Report on Wetland restoration of
barren flood area with the use of compost. Pittsburgh:
National Recycling Congress.
Hey, Donald. 1994. Report on the use of compost for
the Des Plains River Flood Plain. Beltsville, Maryland:
U.S. Department of Agriculture.
Kennamer, J.E. 1994. Role of winter habitat in wild
turkey survival. Turkey Call 94:8-9.
Martin, A.C., A.S. Zim, and A.L. Nelson. 1951.
American Wildlife and Plants. New York: McGraw-Hill.
For More Information
This fact sheet and other information about solid waste issues
are available in electronic format on the Internet at
http://www.epa.gov/osw; select "Reduce, Reuse, Recycle." Use
Internet e-mail to order paper copies of documents. Include the
requestor's name and mailing address in all orders. Address
e-mail to: rcra-docket@epamail.epa.gov.
Paper copies also may be ordered by calling the RCRA Hotline.
Callers within the Washington Metropolitan Area must dial
703 412-9810 or TDD 703 412-3323 (hearing impaired). Long-
distance callers may call 800 424-9346 or TDD 800 553-7672.
The RCRA Hotline operates weekdays, 9 a.m. to 6 p.m.
Mail written document requests to the RCRA Information
Center (5305W), U.S. EPA, 401 M Street, SW., Washington, DC
20460.
United States
Environmental Protection Agency
(5306W)
Washington, DC 20460
Official Business
Penalty for Private Use
$300
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