1. Types of Waste Hazardous: can be liquid, solid, gaseous
Non-hazardous solid waste
Municipal solid waste
Mine and agricultural waste
Non-hazardous liquid wastes
End up in streams and bays: treated or not

2. Municipal Solid Waste (USA)

3. Solid Waste - in US alone:
Tires encircle planet 3 times (each year):
Disposable diapers: to moon & back 7 times (each year)
Office paper: 11’ wall from NYC to Pacific (each yr)
2.5 million nonreturnable bottles - every hour!
3200 plastic shopping bags every second.
132,000 computers & 425,000 cell phones each day!

4. Solid Waste Disposal 1. Sanitary Landfills Different from open dumps
Trash compacted & covered daily with layer of dirt
Lined, monitored, odorless  but will all leak eventually?
Release methane (gh gas) BUT can harvest & sell!
Communities reject new landfills
landfills have filled up and closed. 4

5. Waste Disposal Methods 2. Incinerators: Trash-to Energy
Burning trash reduces volume by 90%, to ash
Saves landfill space
Energy Recovery: harvest heat to produce electricity 5

6. Incinerator (Trash to Energy): Issues
Air pollution including dioxin and CO2
Can be reduced by modern controls IF required and enforced
Can be reduced if pre-sorting systems remove recyclables & unburnable or toxin-emitting materials
Toxins are concentrated in the ash
Dioxins, furan, lead and cadmium
This smaller volume is easier to manage
Costly to build: $ million
Sales of energy and recycling of metals help with expense
NIMBY & ecojustice: Not in My Backyard

7. Waste Disposal Methods 3. Composting
Collect organic, compostable waste, such as food scraps and yard trimmings, sewage sludge
Broken down naturally by bacteria.
This resulting compost can then be used as a natural fertilizer.
Organic wastes 17% of waste stream; 66% composted (US) 7

8. Managing Solid Waste 4. Recycling
Reduces waste disposal problems
Reduces mining
Reduces timber harvesting
Reduces energy needs for producing materials
Thus less air pollution health
Lower CO2 emissions
Cheaper to produce than new from scratch
Saves money through all of these steps

9. Recycling rates in US (EPA 2013)

10. Recycling: INCREDIBLE
Recycling: INCREDIBLE potential to reduce: logging, mining, air pollution from factories, greenhouse gas emissions, energy use, waste going to landfills, and costs
2 million trees /year for paper in US

11. How to Deal With Solid Waste
6. Shrink the Waste Stream: Source Reduction
Redesign products and processes to use less material (and less energy)
Redesign products: longer-lasting, easier to repair, reuse, and recycle
Eliminate unnecessary packaging
Reuse: shopping bags, reusable bottles (freecycle.org)

12. Disposal of US Municipal Solid Waste
Figure 21_13
Disposal of US Municipal Solid Waste

13. How to Deal With Solid Waste
Sanitary landfills
Incineration (burning): energy recovery
Composting
Recycling
Source reduction
Bad ideas:
Open dumps
Ocean dumping
Illegal “midnight dumping”

14. Waste Disposal: Bad Ideas Open Dumps
Widely used near cities in many developing countries
Banned in US, replaced by sanitary landfills

15. Waste Disposal Methods: Bad Ideas Ocean Dumping
NJ coast: long history of dumping until 1990’s
Banned by London Convention (Treaty) took effect 2006
Difficult to enforce

16. Recycling looks better and better.