1. Ch. 19: Waste

2. Section 1: Solid Waste

3. What is solid waste? Any discarded solid material
Examples: coffee grounds, junk mail, cars

4. Problems with Solid Waste
Running out of space to dispose of it
Population growth = more trash
Amount produced in U.S. had doubled since the ‘60s.
Avg. person in U.S. produces about 4.4 lbs/day

5. 2 main types of solid waste:
Biodegradable: can be broken down by biological processes
Newspapers, leather, paper bags, cotton fibers (plant & animal matter)
Nonbiodegradable: cannot be broken down by biological processes
Polyester, plastic (synthetic material)

6. Plastic Problems: Biodegradable or nonbiodegradable?
C & H atoms from petroleum and natural gas put together in unnatural ways that microorganisms can’t break down
May last for hundreds of years

7. Municipal Solid Waste Produced by households and businesses
2% of waste in U.S.
Consists mostly of paper (38.1%)

8. Manufacturing, Mining, & Agricultural Waste:
Manfacturing: produced from products that have been manufactured (scrap metal, plastics, ash)
Mining: leftover rocks and minerals that is often dumped in oceans, rivers, or abandoned mines
Agricultural: biodegradable, but harmful when it contains too many fertilizers, pesticides

9. Solid Waste Management

10. Landfills
wastes put in ground and covered with layer of dirt, plastic, or both
Waste must be prevented from contaminating groundwater
Problems:
Leachate- liquid formed from decomposing garbage
Methane- highly flammable gas produced from decomposition of garbage\
Expensive to build
Where to build them???

13. Incinerators Burn solid waste to reduce amount in landfill
materials can be more toxic than before they were incinerated
small amounts of poisonous gases and particles of toxic heavy metals are released into the air

14. Section 2: Reducing Solid Waste

15. How do we reduce the amount of Solid Waste?
Buy less (What you buy encourages production—glass vs. disposable bottles)
Recycle
Compost
Produce and use more biodegradable products
Remember the 3 R’s:
1) Reduce 2) Reuse 3) Recycle

16. Steps of Recycling: Collect and sort by type
Take to recycling facility
Clean, shred, or crush
Use material to make new products

17. Composting
Compost: decomposed plant & animal matter that can be used to enrich soil
Yard waste, fruit and waste trimmings, table scraps
More oxygen and moisture = faster decomposition

18. Degradable Plastics
Photodegradable plastics: weakened and broken down by the sun
Green plastics: made from sugars in plant material which bacteria can feed on
Problem: these are not completely broken down, but only reduced to smaller pieces

19. Section 3: Hazardous Waste

20. Hazardous Waste Any waste that is a health risk to living things
Solids, liquids, or gases
Often corrosive, explosive, and toxic
Ex.: Love Canal in New York—toxic waste dump site where homes and schools were built

21. Laws
Resource Conservation & Recovery Act (RCRA): requires hazardous waste disposal records to be kept by producers and requires disposal facilities be built to prevent pollution
Superfund Act: gave EPA right to sue individuals who illegally dump hazardous waste and require them to pay for cleanup

22. The Superfund Act

23. Ways to manage hazardous waste:
Redesign manufacturing methods to produce less
Reuse it (ex. sell stuff to other companies that may use it)
Convert it to less harmful substances (neutralize acids and bases, or treat biologically with bacteria or plants)
Incinerate it and bury ashes in landfill (expensive and must have pollution control devices
Export it so it can be treated, disposed of, or recycled

24. Most hazardous waste in U.S. is disposed of on land
Deep-well injection: waste pumped deep into ground into rock below water level and covered with cement
Surface impoundment: pond with sealed bottom---wastes settle to bottom and water evaporates to make room for more
Hazardous waste landfill: put in barrels and buried—have extra safety precautions than regular landfills

25. Hazardous waste at home:

26. Cities have begun to provide collection for household hazardous waste
hazardous materials are sorted for recycling or packed into barrels for disposal
Motor oil: take to an automobile service station or put in designated oil-collection receptors