1. Solid Waste Management and Disposal
Chapter 18
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2. Kinds of Solid Waste
• Solid Waste is generally made of objects or particles that
accumulate on the site where they are produced.
– Typically categorized by the sector of the economy
responsible for producing them.
• Mining Wastes
– Waste Material Left on Surface
– Milling Tailings
– Waste or Tailings Drainage
• Agricultural Waste
– Includes waste from raising animals as well as crop and
tree harvesting.
 90% is used as fertilizer or other forms of soil
enhancement.
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3. Kinds of Solid Waste
• Industrial Solid Waste - Solid waste other than mining.
– Estimated 180-540 million tons annually.
 Demolition Waste
 Sludge
 Combustion Ash
• Municipal Solid Waste
– All the materials people in a region no longer want.
 230 million tons annually.
• In modern society, many products are discarded when they are
broken or worn out, while others only have a temporary use.
– Those that have only temporary uses make up the majority of solid
waste.
• Unites States produces about 230 million tons of municipal solid
waste annually.
– Equates to 2 kg of trash person / day.
 Per capita waste has increased 70% since 1960.
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4. Municipal Solid Waste
• In modern society, many products are discarded when they are
broken or worn out, while others only have a temporary use.
– Those that have only temporary uses make up the majority of
solid waste.
• Unites States produces about 230 million tons of municipal solid
waste annually.
– Equates to 2 kg of trash person / day.
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

5. Waste Generation and Lifestyle
Nations with a higher standard of living tend to produce more municipal solid
•
waste per person than less-developed countries.
–Large metropolitan areas have the greatest difficulty dealing with solid
waste.
Traditional Methods (dumping and burning) no longer accepted.
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6. Methods of Waste Disposal
• Landfills
– Municipal solid waste landfill typically a
depression in impermeable clay layer,
lined with impermeable membrane.
 Each day’s deposit of fresh garbage is
covered with a layer of soil to prevent it
from blowing around and to discourage
animal scavengers.
 Traditionally been primary method of
waste disposal.
 Cheap and Convenient
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7. Landfills
• New landfills have complex bottom layers to
trap contaminant-laden leachate.
– Monitoring systems are necessary to
detect methane gas production and
groundwater contamination.
 In some cases, methane collected and
used to generate electricity.
• Currently cost up to $1 million per hectare to
prepare.
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8. Modern Landfill
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9. Landfills
• Number of landfills is declining.
– Many small landfills not meeting
regulations.
– Capacity has been reached.
• New landfills often resisted due to public
concerns over groundwater contamination,
odors, and truck traffic.
– Politicians are often unwilling to take
strong positions that might alienate
constituents.
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10. Reducing the Number of Landfills
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11. Incineration
• Currently, about 15% of U.S. municipal solid
waste is incinerated.
– Production of electricity partially offsets
disposal costs.
 Most incinerators burn unprocessed
municipal solid waste.
 Mass Burn
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12. Incineration
• Incinerators drastically reduce the amount of municipal waste.
– Up to 90% by volume and 75% by weight.
• Primary risks of incineration involve air quality problems and
toxicity and disposal of ash.
• Even with modern pollution controls, small amounts of
pollutants still released into environment
• Cost of land and construction for new incinerators are also
major concerns facing many communities.
 Construction costs in North America in 2000 ranged
from $45 - $350 million.
• U.S. EPA has not looked favorably on construction of new
waste-to-energy facilities.
– Encouraged recycling and source reduction as more
effective solutions to deal with solid waste.
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13. Producing Mulch and Compost
• Mulch is organic material used to protect areas where the
soil is disturbed, or to control growth of unwanted
vegetation.
– Organic material chopped or shredded into smaller
pieces.
• Composting is using natural decomposition to transform
organic material into compost (humus-like product).
– With proper management of air and water, composting
can transform large quantities over a short period of
time.
• About 3,800 composting facilities currently in use in the
United States.
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14. Diverting Waste Through Composting
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15. Source Reduction
• Simplest way to reduce waste is to prevent it from ever becoming
waste in the first place.
– Source reduction is the practice of designing, manufacturing,
purchasing, using and reusing materials so that the amount of
waste or its toxicity is reduced.
• Design Changes
– Since 2-liter soft drink bottle introduced in 1977, weight has been
reduced by 25%.
• Manufacturing Processes
– Reduce waste, increase efficiency.
• Purchasing Decisions
– Choose reduced packaging and plan quantities accordingly.
• Reusing Items
– Delay or prevent entry of items into waste collection stream.
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16. Recycling
• In the United States, recycling (including
composting) diverted about 30% of solid
waste stream from landfills and incinerators in
2001.
– Benefits
 Resource Conservation
 Pollution Reduction
 Energy Savings
 Job Creation
 Less Need for Landfills and Incinerators
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17. Recycling
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18. Recycling Programs
• Container Laws
– Required deposit on all reusable beverage
containers.
 National bottle bill would reduce litter,
save energy and money, create jobs, and
help conserve natural resources.
• Mandatory Recycling Laws
– Provide statutory incentive to recycle.
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19. Recycling Programs
• Curbside Recycling
– 1990 - 1,000 U.S. cities had curbside
recycling programs.
 Grown to 9,000 cities by 2000.
 Cities with curbside recycling tend to
have higher recycling rates than cities
that lack such programs.
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20. Recycling Concerns
• Plastics are recyclable, but technology
differs from plastic to plastic.
– Milk Container
 High-Density Polyethylene (HDPE)
– Egg Container
 Polystyrene (PS)
– Soft-Drink Bottle
 Poly-Ethylene Terephthalate (PET)
 http://lifecycle.plasticsresource.com/
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21. Increasing Amounts of Plastic in Trash
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