http:www.epa.gov

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http//www.epa.gov/
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Waste Management

• Outline

Composition of Waste
Disposal Landfills,
Incineration, Composting
Recycling reuse (source reduction)
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Composition of Waste
Before recycling
So, all we need to do is recycle, right?
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This is what happens after recycling
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How do we dispose the waste?
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What to dispose?
There are two ways to bury trash
- Dump
- Landfill
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What is a dump?
Dump - an open hole in the ground where trash is
buried and that has various animals (rats, mice,
birds) swarming around. (This is most people's
idea of a landfill!)
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And what is a Landfill?

• Landfill - carefully designed structure built
• into or on top of the ground in which trash
• is isolated from the surrounding environment
• (groundwater, air, rain). This isolation is
• accomplished with a bottom liner and daily
• covering of soil.

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LANDFILL
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The basic parts of a landfill
Bottom liner system - separates trash and
subsequent leachate from groundwater
Cells (old and new) - where the trash is stored
within the landfill
Storm water drainage system - collects rain water
that falls on the landfill
Leachate collection system - collects water that
has percolated through the landfill itself and
contains contaminating substances (leachate)
Methane collection system - collects methane gas
that is formed during the breakdown of trash
Covering or cap - seals off the top of the
landfill
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Landfill Cross-section
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WHAT IS A BOTTOM LINER? 
One or more layers of clay or a synthetic
flexible membrane. If the bottom liner fails,
wastes will migrate directly into the
environment. 
There are three types of liners clay, plastic,
and composite. State-of-the-art plastic (HDPE)
landfill liners are 100 mils or 1/10 of an inch
thick.
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Sanitary and MSW
Sanitary landfill -
landfill that uses a clay liner to isolate the
trash from the environment
Municipal solid waste (MSW) landfill
uses a synthetic (plastic) liner to isolate the
trash from the environment
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LEACHATE
Leachate is water that gets badly contaminated by
contacting wastes. 
It seeps to the bottom of a landfill and is
collected by a system of pipes. 
The pumped leachate is treated at a wastewater
treatment plant (and the solids removed from the
leachate.)
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Seepage of Leachate
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WHAT IS A COVER?
A cover keeps water out (leachate formation). 
It consists of sloped layers
clay or membrane liner
overlain by a very permeable layer of sandy or
gravelly soil (to promote rain runoff),
overlain by topsoil in which vegetation can root
(to stabilize the underlying layers). 
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An experimental covering
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CONSTITUENTS IN LANDFILL GAS
Component          Percent (dry volume basis)

• Methane                            
  40-60
• Carbon Dioxide                  40-60
• Nitrogen                                 2-5
• Oxygen                             
  0.1-1.0
• Ammonia                          
  0.1-1.0
• Sulfides, disulfides,etc.        0-0.2
• Hydrogen                            0-0.2
• Carbon Monoxide                0-0.2
• Trace Constituents            0.01-0.6
• Exact percent varies with the landfills age.

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Disposal of Methane
Communities are increasingly finding ways to use
the gas as a source of energy.
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Combustion and Incineration
Controlled burning
Combustors convert water into steam to generate
heat or electricity.
Burning Municipal solid waste (MSW) can generate
energy while reducing the amount of waste by up
to 90 percent in volume and 75 percent in
weight.
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Incineration Facility
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Drawbacks of Combustion
Does not eliminate waste, but changes the form of
waste into possible hazardous air emissions and
toxic ash.
Spreads hazardous contamination worldwide
contaminating air, soil, and water.
Is a major source of 210 different dioxin
compounds, plus mercury, cadmium, nitrous oxide,
hydrogen chloride, sulfuric acid, fluorides, and
particulate matter small enough to lodge
permanently in the lungs.
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Benefits of Composting
Keeps organic wastes out of landfills.
Provides nutrients to the soil.
Increases beneficial soil organisms (e.g., worms,
centipedes).
Suppresses certain plant diseases.
Reduces the need for fertilizers and pesticides.
Protects soils from erosion.
Assists pollution remediation.
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Benefits of recycling

• Conserves resources.
• Prevents emissions of greenhouse gases and
• water pollutants.
• Saves energy.
• Supplies raw materials to industry.
• Creates jobs.
• Stimulates the development of greener
  technologies.
• Reduces the need for new landfills and
  incinerators.

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Changes in Recycling Rates
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Recycling of Materials
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Reusing materials to minimize waste products

• Use durable coffee mugs.
• Use cloth napkins or towels.
• Refill bottles.
• Donate old magazines or surplus equipment.
• Reuse boxes.
• Turn empty jars into containers for leftover
  food.
• Purchase refillable pens and pencils.
• Participate in a paint collection and reuse
  program.

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Trend
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Recycle
http//www.p2pays.org/recycleguys/teachers.asp
http//www.kidsrecycle.org/green_schools.php