1. Core Case Study: E-Waste – An Exploding Problem
Electronic waste (e-waste) is the fastest growing solid waste problem
Most ends up in landfills and incinerators
Composition includes:
High-quality plastics
Valuable metals
Toxic and hazardous pollutants

3. Core Case Study: E-Waste – An Exploding Problem (cont’d.)
Shipped to other countries
International Basel Convention
Bans transferring hazardous wastes from developed countries to developing countries
European Union
Cradle-to-grave approach

4. Figure 21-1: These workers in Taizhou City in China’s Zhejiang Province are recovering valuable materials from scrap computers shipped from the United States. Question: Have you disposed of an electronic device lately? If so, how did you dispose of it?
Fig. 21-1, p. 576

5. 21-1 What Are Solid Waste and Hazardous Waste, and Why Are They Problems?
Solid waste contributes to pollution and includes valuable resources that could be reused or recycled
Hazardous waste contributes to pollution, as well as to natural capital degradation, health problems, and premature deaths

6. We Throw Away Huge Amounts of Useful Things
Solid waste
Industrial solid waste
Mines, farms, industries
Municipal solid waste (MSW)
Trash
Waste ends up in:
Rivers, lakes, the ocean, and natural landscapes

7. Hazardous Waste Is a Serious and Growing Problem
Hazardous waste (toxic waste)
Threatens human health of the environment
Classes of hazardous waste
Organic compounds
Toxic heavy metals
Radioactive waste

8. Case Study: Solid Waste in the United States
Leader in solid waste problem
In trash production, by weight, per person
98.5% of all solid waste is industrial waste
Most wastes break down very slowly
If at all

9. Figure 21-5: A year’s worth of solid waste produced by family of four in San Diego, California. Recyclable items are on the left and the rest of their MSW is on the right.
Fig. 21-5, p. 579

10. 21-2 How Should We Deal with Solid Waste?
A sustainable approach to solid waste is:
First to reduce it
Then to reuse or recycle it
Finally, to safely dispose of what is left

11. We Can Burn, Bury, or Recycle Solid Waste or Produce Less of It
Waste management
Reduce harm, but not amounts
Waste reduction
Use less and focus on reuse, recycle, compost
Integrated waste management
Uses a variety of strategies

12. To manufacturers for reuse or for recycling Compost Landfill
Raw materials
Processing
and manufacturing
Products
Solid and hazardous wastes generated during the manufacturing process
Waste generated
by households
and businesses
Figure 21-6: We can reduce wastes by refusing or reducing resource use and by reusing, recycling, and composting what we discard, or we can manage them by burying them in landfills or incinerating them. Most countries rely primarily on burial and incineration. Question: What happens to the solid waste you produce?
Food/yard waste
Hazardous waste
Remaining mixed waste
Plastic
Glass
Metal
Paper
To manufacturers for reuse or for recycling
Hazardous waste management
Compost
Landfill
Incinerator
Fertilizer
Fig. 21-6, p. 581

13. We Can Cut Solid Wastes by Refusing, Reducing, Reusing, and Recycling
Waste reduction is based on:
Refuse – don’t use it
Reduce – use less
Reuse – use it over and over
Recycle
Composting
Using bacteria to decompose biodegradable waste

14. Refusing, Reducing, Reusing, and Recycling (cont’d.)
Six strategies:
Change industrial processes to eliminate harmful chemicals
Redesign manufacturing process to use less material and energy
Develop products that are easy to recycle
Eliminate unnecessary packaging
Use fee-per-bag waste collection systems
Establish cradle-to grave responsibility

15. What We Should Do What We Do Reduce Bury (67%) Reuse
Recycle/Compost (23.7%)
Recycle/Compost
Incinerate (9%)
Incinerate
Reuse (0.2%)
Figure 21-7: Priorities recommended by the U.S. National Academy of Sciences for dealing with municipal solid waste (left) compared with actual waste-handling practices in the United States based on data (right). Question: Why do you think most countries do not follow most of the scientific-based priorities listed on the left?
Bury
Reduce (<0.1%)
Fig. 21-7, p. 581

16. 21-3 Why Are Refusing, Reducing, Reusing, and Recycling So Important?
By refusing and reducing resource use and by reusing and recycling what we use, we:
Decrease our consumption of matter and energy resources
Reduce pollution and natural capital degradation
Save money

17. There Are Alternatives to the Throwaway Economy
We increasingly substitute throwaway items for reusable ones
In general, reuse is on the rise
One solution: taxing plastic shopping bags
Ireland, Taiwan, the Netherlands

18. Figure 21-11: Individuals matter
Figure 21-11: Individuals matter. There are many ways to reuse the items we purchase. Question: Which of these suggestions have you tried and how did they work for you?
Fig , p. 583

19. There Is Great Potential for Recycling (cont’d.)
With incentives, the U.S. could recycle and compost 80% of its municipal solid waste
Composting
Mimics nature’s recycling of nutrients
Resulting organic matter can be used to:
Supply plant nutrients
Slow soil erosion
Retain water
Improve crop yield

20. Recycling Plastics Plastics Currently only 7% is recycled in the U.S.
Composed of resins created from oil and natural gas
Currently only 7% is recycled in the U.S.
Many types of plastic resins
Difficult to separate

21. Recycling Has Advantages and Disadvantages
Net economic health
Environmental benefits
Disadvantages
Costly
Single-pickup system
No separation needed

22. Trade-Offs Recycling Advantages Disadvantages
Reduces energy and mineral use and air and water pollution
Can cost more than burying in areas with ample landfill space
Reduces greenhouse
gas emissions
Reduces profits for landfill and incinerator owners
Figure 21-14: Recycling solid waste has advantages and disadvantages (Concept 21-3). Questions: Which single advantage and which single disadvantage do you think are the most important? Why?
Reduces solid waste
Inconvenient for some
Fig , p. 585

23. 21-4 The Advantages and Disadvantages of Burning or Burying Solid Waste
Technologies for burning and burying solid wastes are well developed
air and water pollution
greenhouse gas emissions
buried wastes eventually contribute to the pollution and degradation of land and water resources

24. Burning Solid Waste Has Advantages and Disadvantages
Waste-to-energy incinerators
To heat water or produce electricity
Landfills emit more air pollutants than modern waste-to-energy incinerators
Toxic chemicals that are filtered must be disposed of or stored

25. Electrostatic precipitator
Electricity
Smokestack
Steam
Turbine
Crane
Generator
Furnace
Wet scrubber
Boiler
Electrostatic precipitator
Waste pit
Water added
Figure 21.13: Solutions. A waste-to-energy incinerator with pollution controls burns mixed solid wastes and recovers some of the energy to produce steam to use for heating or producing electricity. Questions: Would you invest in such a project? Why or why not?
Bottom ash
Dirty water
Conveyor
Fly ash
To waste
treatment plant
Ash for treatment, disposal in landfill, or use as landfill cover
Fig , p. 588

26. Waste-to-Energy Incineration
Trade-Offs
Waste-to-Energy Incineration
Advantages
Disadvantages
Reduces trash volume
Expensive to build
Produces a hazardous waste
Produces energy
Concentrates hazardous substances into ash for burial
Figure 21-16: Incinerating solid waste has advantages and disadvantages (Concept 21-4). These trade-offs also apply to the incineration of hazardous waste. Questions: Which single advantage and which single disadvantage do you think are the most important? Why?
Emits some CO2 and other air pollutants
Sale of energy reduces cost
Encourages waste production
Fig , p. 588

27. Burying Solid Waste Has Advantages and Disadvantages
Sanitary landfills
Compacted layers of waste between clay or foam
Bottom liners; containment systems
Open dumps
Widely used in less-developed countries
Rare in developed countries
Large pit
Sometimes garbage is burned

28. Trade-Offs Sanitary Landfills Advantages Disadvantages
Low operating costs
Noise, traffic, and dust
Releases greenhouse gases (methane and CO2) unless they are collected
Can handle large amounts of waste
Filled land can be used for other purposes
Output approach that encourages waste production
Figure 21-18: Using sanitary landfills to dispose of solid waste has advantages and disadvantages (Concept 21-4). Questions: Which single advantage and which single disadvantage do you think are the most important? Why?
No shortage of landfill space in many areas
Eventually leaks and can contaminate groundwater
Fig , p. 589

29. 21-5 How Should We Deal with Hazardous Waste?
A more sustainable approach to hazardous waste:
First, produce less of it
Then, reuse or recycle it
Then, convert it to less-hazardous materials
Finally, safely store what is left

30. We Can Use Integrated Management of Hazardous Waste
Integrated management of hazardous wastes
Produce less
Convert to less hazardous substances
Rest in long-term safe storage
Increased use for postconsumer hazardous waste

31. Radioactive contaminants
Organic contaminants
Inorganic
metal contaminants
Poplar tree
Indian mustard
Brake fern
Sunflower
Willow tree
Landfill
Oil spill
Figure 21-22: Solutions. Phytoremediation involves using various types of plants that function as pollution sponges to clean up contaminants such as radioactive substances (left), organic compounds (center), and toxic metals (right) from soil and water.
Polluted groundwater in
Decontaminated water out
Polluted leachate
Soil
Soil
Groundwater
Groundwater
Rhizofiltration
Roots of plants such
as sunflowers with
dangling roots on ponds
or in greenhouses
can absorb pollutants
such as radioactive
strontium-90 and
cesium-137 and various organic chemicals.
Phytostabilization Plants such as willow trees and poplars can absorb chemicals and keep them from reaching groundwater or nearby surface water.
Phytodegredation
Plants such as poplars can absorb toxic organic chemicals and break them down into less harmful compounds which they store or release slowly into the air.
Phytoextraction
Roots of plants such as Indian mustard and brake ferns can absorb toxic metals such as lead, arsenic, and others and store them in their leaves. Plants can then be recycled or harvested and incinerated.
Fig , p. 593

32. Case Study: Hazardous Waste Regulation in the United States
1976 – Resource Conservation and Recovery Act (RCRA)
EPA sets standards and gives permits
Cradle to grave
Covers only 5% of hazardous wastes

33. Case Study: Hazardous Waste Regulation in the United States (cont’d.)
1980 – Comprehensive Environmental, Compensation, and Liability Act (CERCLA)
National Priorities List
2013 – 1320 Superfund sites; 365 cleaned
Pace of cleanup has slowed
Superfund is broke
Laws encouraging the cleanup of brownfields
Abandoned industrial sites

34. Figure 21-29: Leaking barrels of toxic waste found at a Superfund site that has since been cleaned up.
Fig , p. 596

35. Providing Environmental Justice for Everyone Is an Important Goal
Everyone is entitled to protection from environmental hazards
Which communities in the U.S. have the largest share of hazardous waste dumps?
Environmental discrimination

36. International Treaties Have Reduced Hazardous Waste
Basel Convention
1992 – in effect
1995 amendment – bans all transfers of hazardous wastes from industrialized countries to less-developed countries
2012 – ratified by 179 countries, but not the United States