1. Solid and Hazardous
Waste
March 23, 2011

2. Solid Waste and
Hazardous Wastes
• Solid waste
• Industrial solid
• Municipal solid waste (MSW)
• Hazardous Wastes
• Synthetic organic compounds
• Toxic heavy metals

3. More on Solid Waste
• Industrial solid wastes
• generated by agricultural, mining, and
manufacturing activities
• Municipal solid waste (MSW)
• trash or garbage thrown out by
residential or commercial buildings
• nearly 5 pounds of MSW per person per

4. Methods on Disposing
Solid Waste
• Open dumping
• garbage is deposited and often burned on
large field or holes in the ground
• commonly used in developing countries ;
forbidden in most developed countries
• uncontrolled release of harmful materials
• attraction of rodents and other vermins

5. Methods on Disposing
Solid Waste
• Sanitary Landfills
• meet specific federal requirement
mandated by the Resource
Conservation, and Recovery Act for
• location
• design
• operation

6. More on Sanitary
Landfills
• Must be constructed with special liners and
impermeable soil layers to prevent release
of materials to the environment
• Procedure must be in place to monitor and
control leaks that could contaminate local
water supplies and groundwater
• Wastes are spread out daily and covered
with a layer of either clay or plastic foam

8. More on Sanitary
Landfills
• Disadvantages
• release greenhouse gases (methane and
CO2) as wastes decompose
• liquid toxic materials (known as leachate)
may leach out of landfill and move
download through layers
• Air pollution generated from both the

9. Sustaining Sanitary
Landfills
• Use clay and plastic liners to prevent leaks
• Use pipes that collect leachate
• Provide leachate storage tanks and
treatment systems
• Collect methane gas on site for use as fuel
for electricity generation
• Use groundwater stations to monitor for

10. New York, NY and
Toronto, Canada
• New York: sending most of its trash to
landfills in New Jersey,Virginia, and
Pennsylvania
• Toronto: sending trash generated to
landfills in nearby Michigan
• Shipping trash to surrounding area is
expensive

11. Incineration of Waste
• Advantages
• Reduces the volume of solid waste up to
90%
• Produces steam to create electrical
energy
• Disadvantages
• Creates GHG emissions of CO2

12. Reducing Solid Waste
Production
• Reduce
• Reduce consumption of consumer
products and energy
• Requires less raw material input
• Avoids the production of waste from
mining processes and air pollutants from
energy production

13. Reducing Solid Waste
Production
• Reuse
• Using reusable materials rather than
relying on the production of “one-time
use” item
• Plastic bottles vs. Refillable water
container
• over 2 million plastic bottles are

14. Reducing Solid Waste
Production
• Recycling
• Most wastes that can be recycled are
generated during the manufacturing
process: pre-consumer or internal waste
• Recycle 25-30% of MSW in the U.S.
• Materials that can be recycled:
• paper

15. Reducing Solid Waste
Production
• Two types of recycling: Primary and
Secondary
• Primary Recycling (a.k.a. closed-loop
recycling)
• materials are converted into new
products of the same type
• Example: aluminum can

17. Reducing Solid Waste
Production
• Composting
• A type of recycling
• Using the natural role of decomposing
bacteria and fungi to convert
biodegradable waste into usable soil
amendments

19. Recycling Advantages and Disadvantages
• Advantages
• Reduces GHG emission
• Reduces need for mining of minerals
• Decreases water pollution
• Reduces solid waste production and
disposal