Chapter 22: Waste Management
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Waste
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unwanted material or substance resulting from human activity
or process
municipal solid waste (trash)
hazardous waste
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toxic
chemically reactive
flammable
corrosive
industrial solid waste
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goods
mining
agriculture
petroleum extraction and refining
Waste Management
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minimize your waster
find ways to recycle waste materials
disposing waste safely and effective
Minimizing Waste: Source Reduction
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more efficient use of materials
buy fewer goods
less packaging
use goods longer
reusing goods (purchasing used, donating)
Recovery: Recycling and Composting
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best strategy in waste management
recycling: sending used goods to facilities for
extraction and processing of raw materials
composting: organic decomposition used for
the recovering of organic waste
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Recycling and Composting in the U.S.
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Waste Stream
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Municipal Solid Waste
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in the U.S. 71% consists of paper, yard debris, food
scraps, plastics
packaging
nondurable goods
outdated goods
in 2005 we generated 246 million tons, almost one
ton per person!
average person generates 2 kg of waste per day
Waste Generation
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throwaway society
increase in packaging
poor quality goods
developing countries are becoming more
throwaway societies
recycling has stabilized the waste production
in some industrialized countries
Open Dumping
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trash dumped wherever it suites the person
municipalities began taking care of the trash
specific sites for trash
noxious smoke and nasty smell
cities began burying the trash and burning
some in incinerators (Midlothian)
Sanitary Landfills
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regulated by health and environmental guidelines
resource conservation and recovery act 1976
amended in '84
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partial decomposition by bacteria
compressed by its weight
layered with soil
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speeds decomposition
reduces infestation
limited infiltration of rainwater
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allows biodegradation by aerobic and anaerobic bacteria
Protection against Environmental
Contamination
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location
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away from wetlands
away from earthquake-prone faults
6m above water table
bottom and sides must be lined with plastic
2-4 ft of clay to prevent contamination of aquifers
leachate has to be collected, treated and kept for 30
years after the landfill close to prevent contamination
regular monitoring of groundwater
Closing of Landfill
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Drawbacks
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leachate is inevitable
liner can be punctured
maintenance cease eventually
landfills are kept dry, but bacteria prefer wet
so decomposition slows down
finding suitable areas (not-in-my-backyard)
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garbage barge (NY 1987)
located in poor/minority communities
Incineration: benefits
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it reduces pressure on landfills
it can generate 35% of the energy generated
by coal power plant
can produce gas as a byproduct to be used
for energy
it is a controlled process where garbage is
burned at very high temperatures
Incinerator: Drawbacks
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resulting components are toxic
scrubber and baghouse "clean" the byproduct
toxic gases can still be created and released to the
atmosphere
ashes have to be disposed in hazardous waste
landfills
Texas receives the trash to be incinerated from the
surrounding states
Composting
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recovers organic waste
converts organic waste into mulch or humus
home composting
is used to enrich soil
reduces need for chemical fertilizer
reduces landfill waste
Recycling
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diverted 58 million tons of materials away
from incinerators and landfills in 2005
3 steps
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colleting
processing
manufacturing
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Who Recycles and Who Doesn't
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Financial Incentives
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"bottle bill" passed in 1970
originally 5¢ per container of aluminum or
glass
container litter has decreased 69-84%
total litter has decreased 30-64%
"bigger and better bill"
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include plastic bottles
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will use unclaimed money
legislator has not pass it yet
refunds need to be adjusted for inflation
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26¢ per container might be appropriate
might increase return rates
Industrial Solid Waste
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neither municipal nor hazardous
regulated by state and local government
examples are waste from factories, mining,
agriculture and oil extraction
consists of disposal, reduction and recycling
methods similar to those of municipal waste
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but less restricted
may not require landfill liners
may not include leachate collection systems
may not include groundwater monitoring
Industrial Solid Waste
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less waste = higher efficiency
higher efficiency may mean higher costs
rising costs of waste disposal acts like an
incentive to produce less waste
illegal dumping is a problem in Dallas
Industrial Ecology
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holistic approach
integrating principles of engineering,
chemistry, ecology and economics
reduces resource inputs
minimizes physical inefficiency
maximizes economic efficiency
Industrial Ecology
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industrial systems should function like
ecological systems
Life-cycle analysis
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examine the life-cycle of a product
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from its origin as raw material to the end product
to its use
to its disposal
study how waste products from one can be
the raw material in another
Industrial Ecology
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businesses are taking advantage of the
results of industrial ecology as
it reduces waste
lessen impact on Earth
saves money
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American Airlines are buying new planes
Interface (carpet and tile company)
Hazardous Waste
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materials that can harm human health
ecological damage
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die-offs caused by toxins waste in rivers & lakes
atmospheric pollution
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trash fires
Hazardous Waste
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Ignitable
corrosive
reactive
toxic
Gas fire in Dallas, 2008
Sources
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Household
biggest source of hazardous waste
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paints
batteries
oils
solvents
cleaning agents
lubricants
pesticides
Organic Compounds
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particularly hazardous as their toxicity
persists over time
resist bacterial, fungal and insect activity
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plastics
rubber tires
pesticides
solvents
wood preservatives
Heavy Metals
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persist over time
become a problem when disposed improperly
widely used in industry
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lead
mercury
chromium
arsenic
cadmium
tin
copper
Proceeding for Disposal
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Love Canal (Erin Brockovich)
since then people are more aware
1980s sites were designated
facilities were designated for exchange and
reuse of chemicals
EPA set standards for managing hazardous
waste
problem of illegal dumping
Methods of Disposing Hazardous
Waste
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help isolate the hazardous waste from
people, wildlife and ecosystems
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landfill
surface impoundments
deep-well injection
Landfill
more strict guidelines than those of
municipal waste
 several
liners
 leachate removal system
 located far from aquifers
Surface Impoundments
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liquid hazardous waste
stored in ponds
lined with plastic and clay
water is allowed to evaporate leaving a residue of solid
hazardous waste
once dry the material is removed and transported for
permanent disposal
used ONLY for temporary storage
problems:
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underlying can crack and leak
materials may evaporate and blow to other areas
rainstorms may cause overflow
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Surface Impoundment
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Deep-Well Injections
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long term disposal
well is drilled beneath the water table into porous
rock
isolated from water table and human contact
9 billion gallons of hazardous waste per year are
placed in injection wells in the U.S.
problems:
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wells can corrode
wastes can leak into soil eventually entering aquifers
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Deep-Well Injection
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E-Waste
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most of them are disposed
in landfills
should be treated as hazardous
waste
must be kept out of conventional landfills
recycling has become more popular
Cleaning Contaminated Sites
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Difficult, expensive, time-consuming
1980 CERCLA
federal program to clean up sites
"superfund" legislation based on taxes to petroleum
industry and chemical raw materials
EPA evaluates the site
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how toxic it is
how near it is to a developed area
if there is a threat to drinking water
Problems
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congress let the superfund tax expire in 2004
since then the superfund went bankrupt
government hasn't restore funds for such
program yet
fewer cleanups are being completed
As of mid-2007
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65% of the sites listed as priority sites have been
cleaned
average cost of 25 million dollars
takes 12-15 years to clean up a site
we may have no idea of how to dispose some of the
toxins
U.S. and other countries must PREVENT hazardous
waste contamination in the first place
The End