Chapter 22: Waste Management

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Chapter 22 Waste Management
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Waste

• unwanted material or substance resulting from
  human activity or process
• municipal solid waste (trash)
• industrial solid waste
• goods
• mining
• agriculture
• petroleum extraction and refining
• hazardous waste
• toxic
• chemically reactive
• flammable
• corrosive

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Waste Management

• minimize the amount of waste we generate
• find ways to recycle waste materials
• disposing waste safely and effective

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Minimizing Waste Source Reduction

• more efficient use of materials
• buy fewer goods
• less packaging
• use goods longer
• reusing goods (purchasing used, donating)

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Recovery Recycling and Composting

• 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

• 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• outdated goods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

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Waste Generation

• 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

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Open Dumping

• 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)

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Sanitary Landfills

• regulated by health and environmental guidelines
• resource conservation and recovery act 1976
• amended in '84
• partial decomposition by bacteria
• compressed by its weight
• layered with soil
• speeds decomposition
• reduces infestation
• limited infiltration of rainwater
• allows biodegradation by aerobic and anaerobic
  bacteria

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Protection against Environmental Contamination

• location
• 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

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Closing of Landfill
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Drawbacks

• 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)
• garbage barge (NY 1987)
• located in poor/minority communities

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Incineration benefits

• 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

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Incinerator Drawbacks

• 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

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Composting

• 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

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Recycling

• diverted 58 million tons of materials away from
  incinerators and landfills in 2005
• 3 steps
• colleting
• processing
• manufacturing

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• Who Recycles and Who Doesn't

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Financial Incentives

• "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

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"bigger and better bill"

• include plastic bottles
• will use unclaimed money
• legislator has not pass it yet
• refunds need to be adjusted for inflation
• 26 per container might be appropriate
• might increase return rates

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Industrial Solid Waste

• 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
• but less restricted
• may not require landfill liners
• may not include leachate collection systems
• may not include groundwater monitoring

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Industrial Solid Waste

• 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

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Industrial Ecology

• holistic approach integrating principles of
  engineering, chemistry, ecology and economics
• reduces resource inputs
• minimizes physical inefficiency
• maximizes economic efficiency

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Industrial Ecology

• industrial systems should function like
  ecological systems
• Life-cycle analysis
• examine the life-cycle of a product
• 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

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Industrial Ecology

• businesses are taking advantage of the results of
  industrial ecology as
• it reduces waste
• lessen impact on Earth
• saves money
• American Airlines are buying new planes
• Interface (carpet and tile company)

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Hazardous Waste

• materials that can harm human health
• ecological damage
• die-offs caused by toxins waste in rivers lakes
• atmospheric pollution
• trash fires

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Hazardous Waste

• Ignitable
• corrosive
• reactive
• toxic

Gas fire in Dallas, 2008
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Sources

• industry
• mining
• household chemicals
• small businesses
• agriculture
• utilities
• building demolition

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Household

• biggest source of hazardous waste
• paints
• batteries
• oils
• solvents
• cleaning agents
• lubricants
• pesticides

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Organic Compounds

• particularly hazardous as their toxicity persists
  over time
• resist bacterial, fungal and insect activity
• plastics
• rubber tires
• pesticides
• solvents
• wood preservatives

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Heavy Metals

• persist over time
• become a problem when disposed improperly
• widely used in industry
• lead
• mercury
• chromium
• arsenic
• cadmium
• tin
• copper

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Proceeding for Disposal

• 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

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Methods of Disposing Hazardous Waste

• help isolate the hazardous waste from people,
  wildlife and ecosystems
• landfill
• surface impoundments
• deep-well injection

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Landfill

• more strict guidelines than those of municipal
  waste
• several liners
• leachate removal system
• located far from aquifers

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Surface Impoundments

• 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
• 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

• 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
• wells can corrode
• wastes can leak into soil eventually entering
  aquifers

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• Deep-Well Injection

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E-Waste

• 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

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Cleaning Contaminated Sites

• 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
• how toxic it is
• how near it is to a developed area
• if there is a threat to drinking water

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Problems

• 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

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As of mid-2007

• 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