1. Waste management
trash, recyclables, hazardous waste, nuclear waste, e-waste, biological waste, . . .

2. Once upon a time
Any waste just thrown into a pit, covered once in a while with soil

3. Dump became a ``landfill’’
                                                                                                                            
Sanitary landfill
Lined, to prevent leachate from reaching groundwater
Often, escaping gas collected (methane)
Dust and noise control
Once covered, ``restoration’’ with native plants.

4. Fresh Kills landfill

6. What kinds of ``waste’’ are there?
``trash’’
Paper, cardboard, books
Metals
Glass
Plastics
Organics: food, yard, bodily waste, wood
Rubber, textiles, leather
= MSW
Electronic waste
Large manufactured goods (e.g. refrigerator)
Toxic waste—chemicals
Mining waste 75%
Biological waste
Nuclear waste
MSW = ~3% of all waste

8. MSW U.S. produces most About 4-5 lbs/person How much do you produce?
How can you produce less?

10. Incineration Some: refuse-derived fuel Non-combustibles removed first
Some: Mass burn
Burn the material ``as is’’
Reduces volume
Problems?
Ash
Metals
Wet waste
May use heat from combustion to generate electricity
Some: refuse-derived fuel
Non-combustibles removed first
Stuff remaining, inc. paper, plastic, is shredded and burned
Why?

11. The 3 R’s REDUCE REUSE RECYCLE
Recycle is the third option, not the first

12. How reduce amount of waste produced?
Ideas?
Eliminate packaging
Change formulation of a product
Avoid excess purchases
Repair

13. How reuse? Ideas? Bring own bags when shopping
Wash containers (Chinese food)
Back of printed paper for scrap

14. Recycling Is it worth it? Costs and benefits
Environmental and economic
Material
Energy savings
Air poll decrease
Aluminum
95%
Carboard 24
Glass
5-30 20
Paper 40 73
Plastics 70
steel 60

15. Recovery rates Material % that is recycled or composted Paper 52%
Plastic soft drink bottles 31
Aluminum cans 45
Steel 63
Major appliances 67

16. Hazardous waste What is it? Ignitable, corrosive, toxic, reactive
Includes waste from large producers such as chemical plants, petroleum refineries, electroplating industry, large paint shops.
But also: dry cleaners, hospitals, car-repair shops, university labs

17. How much?
More than 40 million tons a year in the U.S.

18. What to do with it? Produce less recycle
Engineers in many industriesdevelop new processess that use less materials and produce less waste
recycle

19. How regulated? Resource Conservation and Recovery Act
= RCRA, pronounced ``rikrah’’
Objectives:
"to promote the protection of health and the environment and to conserve valuable material and energy resources.“
Only 5% of haz waste. Doesn’t include:
Radioactive waste, mining waste, waste from very small generators (< 100 kg/month)

20. Types of hazardous waste
Toxic chemicals
Metals (e.g., lead)
Infectious waste (hospitals)
Radioactive waste
Organic compounds

21. What can be done about hazardous waste?
Some is recycled
Solvents can be recovered
Lead can be recovered
Small % now about 5% is recycled

22. What can be done about hazardous waste?
Incineration
Destroy the toxic compound
Sometimes, recover part (metals)
Air emissions are regulated by Clean Air Act
One issue: dioxins produced when plastics not burned at high enough temperatures

23. What can be done about hazardous waste?
If liquid (e.g., paint thinner, solvents, etc)
Most hazardous liquids are injected into the ground
Deep
Into porous rock (often)
Sometimes into previously drilled holes
Regulated in part by: Safe Drinking Water Act