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What Are the Options
For Waste Disposal?
Many cities have no controlled system for waste disposal. Waste is
either burned in pits, dumped in random locations, or disposed
of in uncontrolled dumps without any further management. All
these actions harm public health and the environment. Controlled waste
disposal can help improve and protect the health of local populations and
preserve valuable environmental resources, such as groundwater and
drinking water. You have two options for waste disposal: operate a properly
designed, constructed, and managed landfill or burn the waste in a
controlled facility that converts waste to energy. This fact sheet describes the
dangers of open dumping and burning and explains procedures for proper
landfill disposal and controlled burning. At the end of this fact sheet is an
example of how using one of these options benefitted the Gaza Strip.
What Problems Can Uncontrolled Dumping and Burning
Cause?
Most uncontrolled dumps are many years old, having grown over time from small dumps
to large, unmanaged waste sites. Uncontrolled dumps have significant environmental
impacts. As the waste decomposes, it creates leachate—a mix of toxic and nontoxic
liquids and rainwater—which may get into local water supplies and contaminate the
drinking water. Uncontrolled dumps also release gases that are explosive and flammable.
In some instances, waste is burned at these dumps, which poses a direct safety threat
because of the danger of explosion. The air pollution created by burning harms local
communities. Improper waste disposal also produces greenhouse gases (GHGs), which
contribute to climate change. In contrast, properly designed, constructed, and managed
landfills aim to prevent or minimize health and environmental impacts. They have liners
and leachate collection systems that protect groundwater, and gas collection systems that
contain or safely burn methane from landfills.
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Properly Designed, Constructed, and
Managed Landfills
To protect human health and the environment,
communities should discourage the use of existing
open dumps and establish a managed site for solid
waste disposal. Safe, well-controlled waste placement
distinguishes a landfill from an open dump. If you
want to provide a properly designed, constructed, and
managed landfill in your community, you can either
convert an existing uncontrolled dump or construct a
new landfill.
Converting Existing Open Dumps to
Properly Designed, Constructed, and
Managed Landfills
Existing open dumps can be converted to landfills in
three phases:
Phase 1: Convert open dumps to
controlled dumps. The steps involved in this
phase include: (1) covering exposed wastes with soil,
sand, or clay; (2) installing passive gas vents to safely
control methane emissions; (3) establishing rules for
onsite scavenging or wastepicking; and (4) organizing
wastepickers into recycling groups.
Phase 2: Convert controlled dumps to
Simple landfills During this phase, basic
engineering techniques are gradually employed to
stabilize the waste and control environmental releases.
The waste is spread and compacted in layers and
leachate is collected. At this point, scavenging or
wastepicking activities should be confined to areas of
the landfill away from compaction areas and heavy
equipment.
Phase 3: Transition from simple landfills
to properly designed, constructed, and
managed landfills. Activities during this phase
include: (1) developing formal engineering designs;
(2) providing daily onsite management by trained
workers; (3) placing waste in small working areas
with daily cover; (4) collecting and burning landfill
gas; and (5) installing liners and piping to collect and
treat leachate.
Establishing a New Properly Designed,
Constructed, and Managed Landfill
The process of developing a properly designed,
constructed, and managed landfill can be divided into
four steps:
Step 1: Selecting the site. Several factors
should be considered when selecting a site for a
landfill:
• Geological factors. Landfills produce leachate
when waste is exposed to rainwater while it is
decomposing. If leachate leaks out of the landfill, it
can contaminate groundwater and drinking water.
To protect local water supplies, the site must have
a geology that naturally prevents or limits the
release of leachate to the environment. For
example, locating the landfill in an area with clay
soils—through which water cannot flow—will
provide this protection.
• Distance to the location of the waste. The
farther a landfill site is from the point where the
waste is generated and collected, the more waste
transport costs. It is generally most cost-effective to
use a site a relatively short distance away.
• Landfill capacity. Determine how many years the
landfill will be able to accept waste. Calculate the
volume (or capacity) of the landfill by using the
following factors: amount of waste generated per
person per year, population size, anticipated
population and economic growth, and the number
of years the landfill will be in operation.
• Areas to avoid. Landfills should not be located
near airports, schools, drinking water sources, or
flood-prone areas.
Step 2: Gaining public acceptance.
Residents who live near the chosen landfill site may
have concerns about its environmental and health
impacts. You can increase public acceptance by
educating local residents and business owners about
how the landfill will benefit the community (e.g., by
improving public health and safety, creating local
jobs, and stimulating economic development). You
also can describe what steps will be taken to protect
public health and the environment.
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Step 3: Designing the landfill. Design
requirements for a properly designed, constructed,
and managed landfill include the following (see
Figure 1):
• Liners. Liners are used to prevent leachate from
entering groundwater by keeping fluids within the
landfill area. Liners must be made of relatively
impermeable material such as compacted soil or
clay, synthetic materials (e.g., plastic), or a
composite of earthen and synthetic materials. They
are placed in the bottom of a new landfill before
disposing of any waste. Liners are important for
landfills located on sandy or other soils through
which water can easily flow.
• Leachate collection and treatment. In a properly
lined landfill, leachate accumulates within the
landfill. Therefore, the landfill should include
equipment to collect and divert the leachate from
the landfill and treat it. Perforated piping, for
example, can be installed to collect the leachate
and divert it to a nearby treatment facility (similar
to a water treatment facility). Treated leachate can
then be safely released to the environment.
• Gas collection and treatment. Bacteria that are
naturally present in landfills produce methane as
they decompose and break down the waste.
Methane poses a danger because it is explosive and
can start fires. In addition, methane from landfills
and other sources is harmful to the atmosphere
and climate because it is a greenhouse gas.
Therefore, monitoring the amount of and
controlling methane is very important. Typically, a
system is installed to monitor, collect, and burn
the gas. In some instances, power stations can
collect the gas and use it to generate electricity.
Figure 1—Cross-Section of a Typical, Properly
Designed, Constructed, and Maintained Landfill
Liner
Monitoring
Well
• Site access. Access to the landfill must be strictly
controlled to prevent injury or illegal dumping.
This can be done by building a fence around the
site.
Step 4: Operating the landfill. A trained
landfill manager should be hired to properly operate
and manage the site. Before any waste is disposed of,
the manager should develop a plan to serve as the
operational guide for the site. It should specify, in
detail, where on the site waste is to be placed, how
the site will be operated, at what points the garbage
will be covered by soil, and how environmental
problems (e.g., animals, litter, fires, gas, leachate) will
be addressed. The plan also should provide details of
equipment, materials, and staff needed to operate the
site; list the environmental agency's required
monitoring and reporting activities; and clearly
describe when and how each part of the site will be
covered and maintained once it has reached its
capacity.
Burning Waste in a Controlled Facility
Combustion, or the controlled burning of waste at
high temperatures to produce steam and ash, is
another waste disposal option and an alternative to
landfilling. Waste combustion reduces the volume of
solid waste to be disposed of by approximately 90
percent. This is especially attractive in crowded cities
that do not have enough land available for landfills.
In addition, solid waste can provide a continuously
available source for generating energy through
combustion. When steam-driven turbines convert the
thermal energy from combustion into electrical
energy, the process is called "waste-to-energy" (WTE).
Steam or hot water produced during combustion also
may be sold directly for industrial processes or space
heating, or it may be used to generate chilled water
for air conditioning. Selling the recovered energy or
water in one of these forms helps offset the high costs
of construction and operation of waste combustion
facilities, but it does not cover them entirely.
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Waste combustion, however, has significant disadvantages. Constructing a WTE facility requires
large amounts of money. The combustion process also creates air pollution, ash, and waste water, all
of which must be properly managed using technical monitoring, containment, and treatment
systems. If these byproducts are not controlled, harmful pollutants will be released into the
environment. Operators of these facilities must be well-trained and certified to ensure proper
management. You must also find disposal options for waste that cannot be burned.
CASE STUDY
CONVERTING OPEN DUMPS INTO PROPERLY DESIGNED, CONSTRUCTED, AND MANAGED
LANDFILLS IN GAZA
The German Agency for Technical Cooperation (GTZ) recently assisted the Solid Waste
Management Council of the Gaza Strip in closing down a number of open dumps and
building a properly designed, constructed, and managed landfill. The first step in
constructing a landfill was to assess soil and groundwater conditions at several potential locations.
Two important site selection criteria were soil with enough clay content to serve as a natural
barrier to leachate and a site away from major drinking water sources. Once the team found a
site, it hired local contractors to prepare the landfill site and cover the surface with an asphalt
liner. It then built a storage pond and installed drainage
pipes that carry leachate into the pond. Since Gaza has no
municipal wastewater treatment facilities to treat the
leachate, the team installed pumps and a sprinkler system
that recirculates the leachate back to the landfill, allowing
it to evaporate. The team considered recirculation to be a
reasonable option because it did not expect the region's dry
climate to generate much leachate and anticipated most of
the leachate would be managed through evaporation.
However, the storage pond and pumping system were later
enlarged to handle larger-than-expected leachate levels.
Once the landfill was in operation, they closed the open
dumps, controlled access to the new site and began transfer
of waste into the new landfill. The team expects the landfill
to last for approximately 13 years. As the team closes filled
sections of the landfill, it covers the area with compost
generated from digging up and screening organic material
from older sections of the landfill. The compost serves as a
cost-effective final cover that helps break down the
methane as it leaves the landfill surface. The compost also
supports vegetation that grows on the landfill surface,
which helps reduce the flow of leachate. The project is a
successful example of an upgrade of disposal standards. For
more information on the Gaza landfill project, visit the Swiss
Agency for Development and Cooperation Web site at
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DEFINITIONS
Combustion: Refers to controlled
burning of waste to reduce waste
volume and perhaps to generate
energy.
Impermeable: The property of a
material or soil that does not allow
the movement or passage of water.
Leachate: A mix of toxic and
nontoxic liquids and rainwater
created in the landfill environment
that may pose a threat to local
ground-water supplies.
Methane: Also called natural gas,
methane is generated when waste
in a landfill decomposes. It makes
up approximately 50 percent of the
gases emitted from landfills.
United States Environmental
Protection Agency
EPA530-F-02-26c
(5306W)
Solid Waste and Emergency Response
May 2002
www. epa. gov/globalwarming
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