Hazardous Waste

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Solid & Hazardous Waste
•Landfills
•Incineration
•Hazardous Waste
•Hazardous Waste
Management
What Happens to Mining Waste?
• Slag- by product that is left when the
mineral part is separated from unwanted
material and can be used for concrete
Sanitary Landfills
• Land fills in Saint Louis
• Location
– Far enough away from population centers but
not too far (transportation cost)
– Dependent on geology and climate(drainage,
rainfall, flooding)
Sanitary Landfills: Design
Landfill in Maryland Heights MO
Sanitary Landfills: Design
•Liner- prevents
leachate from
entering
groundwater
•Collection Pipeschannel leachate
for treatment
•Clay cover- Seals
solid waste in
Problems Associated with Landfills
• Methane gas
– Produced by microorganisms that break down
waste
– Flammable and explosive
– can be used for energy
• Contamination of surface and
groundwater
– Seeping through unlined or cracks in the lining
of landfills
Methane Gas
Methane from a
landfill
collected and
burning
Hazardous Waste
• What is hazardous waste?
– Dangerously reactive, corrosive, explosive, or
toxic chemicals
– Can be in all states of matter: solid, liquid, gas
• How much of solid waste is hazardous?
– About 1%
Types of Hazardous Waste
• Dioxins
– By-products of combustion of chlorine
compounds
– Source include: waste incinerators, iron ore
mills, coal combustion,
– Why are they harmful
• Accumulate in tissue
• Cause cancer, reproductive, neurological, immune
system affected
Times Beach, MO (Route 66 State Park)
• Dioxin mixed with oil
and sprayed on dirt
roads to control dust
• Region flooded
• Dangerous levels of
Dioxin found
• Evacuated 1982
• Dioxin cleaned up and
park opens 1999
Types of Hazardous Waste (ctd)
• PCBs
– Group of industrial chemicals used in electrical
transformers, vacuum pumps, adhesives, etc.
– Can damage multiple organs especially interfere
with thyroid function
– Why are they dangerous?
• Resist break-down (chemical or biological)
• Ocean life lives in PCB contaminated sediment and pass
the PCBs up the food chain
http://www.sciencedaily.com/videos/2009/0110-clam_cleanup.htm
Hazardous Management
Hazardous Waste Management
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•
•
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Long term storage in specialized landfills
Reduce the amount produced
Incineration
Biologically
– Microorganisms break down waste into
harmless substance like water
– Plants take the waste into their tissues and
then are disposed of in hazardous waste
landfills
http://www.ecocycle.org/zerowastevideo/
Current Article
• Find an article from a news source
(newspaper, magazine, text from newscast)
can be print or digital about solid waste,
hazardous waste, waste management, or the
environmental impact of waste
• 1 paragraph summary
• 1 paragraph your opinion (must include what
you learned)
• Copy of your article
• Due 1/14 Friday
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