Ch 16: Solid and Hazardous Waste

Ocean Garbage Patches: There is No “Away”

• Plastics trapped in ocean gyres
• Cover large surface areas + depths
• What’s the problem?

Waste Generation is on the Rise

Why?
• Growing population
• More packaging
• More single-use items

We Haven’t Always Had A Waste Problem..

Nature has a closed-loop system
• Humans had a closed-loop
system prior to industrialization
• Cradle-to-cradle

Types of Waste

• Municipal solid waste (MSW)
• From homes, workplaces
• Industrial solid waste
• Mining, ag, consumer goods
production
• Disposal:
• Open dumps
• Underground wells
• Incineration
• Landfills

Municipal Solid Waste (MSW)

US leads the world in production!
• 70% = paper, yard waste, food &
plastics
• Packaging, non-durable goods,
compostables

Modern Waste Management

3 aims:
• Minimize waste generated
• Recover & reuse or recycle waste
materials
• Dispose of wastes safely

The 4 Rs: Refuse, Reduce, Reuse, Recycle

• Refuse
• Don’t use things that will quickly
become waste
• Reduce
• Saves money, resources
• Minimizes pollution
• How do we do it?

• Reuse
• Mostly involves changes in habits
• What are some examples?
• Recycle
• Modify and repurpose materials

Recycling

• Recyclable materials:
• Paper, glass, aluminum, steel,
some plastics
• Primary recycling vs. secondary
recycling

3 steps in recycling

• 3 Steps
• Collecting and processing
• Conversion to new products
• Consumer purchase

The pros and cons of recycling

• Recycling Pros
• Reduces energy & resource use
• Reduces air & water pollution
• Recycling Cons
• Price vs. landfilling
• Convenience

MSW Incineration + the pros and cons

• Mixed garbage burned at high temps
• Pros: Weight and volume are reduced
• Cons: Ash – hazardous waste, and air
pollution

Sanitary Landfills

Waste is buried in engineered mounds
• Pit is lined
• Bacteria partially decompose waste
• Waste is layered with soil
• Capped with 3 layers at the end of its life
• EPA standards: RCRA (1976)

Modern Landfills

Note: leachate collection, gas pipes, groundwater monitoring &
clay lining

• Landfills have been closing
• Why?
• What happens to them?
• Drawbacks of landfills
• CH4 production
• Leaking leachate
• Slow decomposition
• NIMBY
• Plastics & tires

Waste-to-Energy

• Heat from incineration used to
generate electricity or heat
buildings
• Methane captured from landfills
to be burned

Hazardous Waste

• Solids, liquids, or gases that are
flammable, corrosive, reactive, or toxic
• Sources: industry, mining,
home products, electronics

Love Canal

• Series of events:
• Love Canal left unfinished
• Dump site for MSW and then for
Hooker Chemical
• Development: housing and two
schools
• Chemicals seeped unmonitored
from 1953-1977
• Birth defects, cancers, miscarriage
• Led to the passage of the
Superfund Bill (1980)

Clean-Up

• CERCLA/Superfund (1980)
• Polluter-pays + slush fund
• Clean-up: $25 million, 12-15 years

Hazardous Waste Disposal

Historically: The solution to pollution is
dilution
• Now...
• Collection dates & locations
• Cradle to grave permits (RCRA ‘76)
• Pressure to reduce wastes
• Disposal methods
• Landfills
• Surface impoundments
• Injection wells

E-waste

• Electronic wastes
• Valuable source of secondary raw
materials
• Also sources of toxins and
carcinogens
• Much is exported to poorer
nations
• Basel Convention
• Human health concerns
• Environmental concerns
• Solutions?

We Live in a Throwaway Economy

• How did it come to be this way?
• Abundant & cheap resources
• Limited long-view
• Planned obsolescence

How can we shift to a
low-waste economy?

• Behavioral changes
• Policy changes
• Cradle-to-cradle design

Conclusions

• The U.S. has made great strides in addressing solid waste
• The focus for the present and future needs to be reduction
• Reuse & recycling are growing
• Continued growth will happen through market forces, policy, and consumer choice
• Disposal is now safer for people and the environment
• Finding ways to reduce, reuse & recycle provide unique technological
and behavioral challenges