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Title: Solid%20and%20Hazardous%20Waste


1
Solid and Hazardous Waste
2
(No Transcript)
3
Disposable?
  • We live in a disposable society, trash is an
    everyday reality for every American.
  • What does this term mean?
  • Wall-E
  • Think about our habits and perception of trash.
  • What are the factors in identifying a disposable
    society?

4
Central Case Transforming New Yorks Fresh
Kills Landfill
  • The largest landfill in the world, it closed in
    2001
  • Staten Island residents viewed the landfill as an
    eyesore and civic blemish
  • It was briefly reopened to bury rubble from the
    World Trade Center after the September 11, 2001,
    attack
  • New York plans to transform the landfill into a
    world-class public park

5
Core Case Study Love Canal There Is No Away
  • Between 1842-1953, Hooker Chemical sealed
    multiple chemical wastes into steel drums and
    dumped them into an old canal excavation (Love
    Canal).
  • In 1953, the canal was filled and sold to Niagara
    Falls school board for 1.
  • The company inserted a disclaimer denying
    liability for the wastes.

6
Core Case Study Love Canal There Is No Away
  • In 1957, Hooker Chemical warned the school not to
    disturb the site because of the toxic waste.
  • In 1959 an elementary school, playing fields and
    homes were built disrupting the clay cap covering
    the wastes.
  • In 1976, residents complained of chemical smells
    and chemical burns from the site.

7
Core Case Study Love Canal There Is No Away
  • President Jimmy Carter declared Love Canal a
    federal disaster area.
  • The area was abandoned in 1980 (left).

Figure 22-1
8
Core Case Study Love Canal There Is No Away
  • It still is a controversy as to how much the
    chemicals at Love Canal injured or caused disease
    to the residents.
  • Love Canal sparked creation of the Superfund law,
    which forced polluters to pay for cleaning up
    abandoned toxic waste dumps.

9
Waste
  • What is your definition of waste?

10
Waste
  • Any discarded material for which no further sale
    or use is intended
  • examples residue, chemical by-products, unused
    virgin material, spill absorbent material

11
WASTING RESOURCES
  • Solid waste any unwanted or discarded material
    we produce that is not a liquid or gas.
  • Municipal solid waste (MSW) produce directly
    from homes.
  • Industrial solid waste produced indirectly by
    industries that supply people with goods and
    services.

12
Solid Waste
  • Any garbage refuse sludge from a waste
    treatment plant or air pollution control
    facility and other discarded material (including
    solid, liquid, semi-solid or contained gaseous
    material) generated from any industrial,
    commercial or community activities mining or
    agricultural operations

13
Solid Waste Exclusions
  • Solid or dissolved materials in domestic sewage
    or irrigation return flows
  • Industrial discharges subject to CWA regulations,
    including POTW
  • Source, special nuclear or by-product material
    defined by the Atomic Energy Act of 1954

14
Ways to reduce waste that enters waste stream
  • Waste stream flow of waste as it moves from its
    sources toward disposal destinations
  • More efficient use of materials, consume less,
    buy goods with less packaging, reusing goods
  • Recovery (recycling, composting) next best
    strategy in waste management
  • Recycling sends used goods to manufacture new
    goods
  • Composting recovery of organic waste
  • All materials in nature are recycled

15
How Much Trash is Generated?
  • Of the 251 million tons (228 million metric tons)
    of trash, or solid waste, generated in the United
    States in 2006, about 81.8 million tons (74.2
    million metric tons), or 32.5 percent, was either
    recycled or composted source EPA.

16
Materials Discarded in a Municipal Landfill
  • Paper and paperboard 41.0
  • Yard waste 17.9
  • Glass 8.2
  • Metal 8.7
  • Rubber, leather, textiles 8.1
  • Food waste 7.9
  • Plastic 6.5
  • Miscellaneous inorganic 1.6

17
Electronic Waste A Growing Problem
  • E-waste consists of toxic and hazardous waste
    such as PVC, lead, mercury, and cadmium.
  • The U.S. produces almost half of the world's
    e-waste but only recycles about 10 of it.

Figure 22-4
18
Waste generation is rising in the U.S.
  • In the U.S,, since 1960, waste generation has
    increased by 2.8 times

19
Waste disposal
20
WASTING RESOURCES
  • Solid wastes polluting a river in Jakarta,
    Indonesia. The man in the boat is looking for
    items to salvage or sell.

Figure 22-3
21
Trash For Sale
  • The US sells its trash to China for recycling.
  • The turn in the economy has devalued the
    recycling industry

22
INTEGRATED WASTE MANAGEMENT
  • We can manage the solid wastes we produce and
    reduce or prevent their production.

Figure 22-5
23
WASTING RESOURCES
  • The United States produces about a third of the
    worlds solid waste and buries more than half of
    it in landfills.
  • About 98.5 is industrial solid waste.
  • The remaining 1.5 is MSW.
  • About 55 of U.S. MSW is dumped into landfills,
    30 is recycled or composted, and 15 is burned
    in incinerators.

24
Burying Solid Waste
  • Most of the worlds MSW is buried in landfills
    that eventually are expected to leak toxic
    liquids into the soil and underlying aquifers.
  • Open dumps are fields or holes in the ground
    where garbage is deposited and sometimes covered
    with soil. Mostly used in developing countries.
  • Sanitary landfills solid wastes are spread out
    in thin layers, compacted and covered daily with
    a fresh layer of clay or plastic foam.

25
Sanitary landfills are regulated
  • Sanitary landfills waste buried in the ground
    or piled in large, engineered mounds
  • Must meet national standards set by the EPA under
    the Resource Conservation and Recovery Act (RCRA)
    of 1976
  • Waste is partially decomposed by bacteria and
    compresses under its own weight to make more
    space
  • Layered with soil to reduce odor, speed
    decomposition, reduce infestation by pets
  • When a landfill is closed, it must be capped and
    maintained

26
40 CFR Parts 239-259
  • The purpose of this part is to establish minimum
    national criteria under the Resource Conservation
    and Recovery Act (RCRA or the Act), as amended,
    for all municipal solid waste landfill (MSWLF)
    units and under the Clean Water Act, as amended,
    for municipal solid waste landfills that are used
    to dispose of sewage sludge. These minimum
    national criteria ensure the protection of human
    health and the environment.

27
Regulatory Guidelines
  • Subtitle D, of RCRA regulates non-hazardous
    waste
  • Siting
  • Design
  • Operation
  • Monitoring
  • Closure and post-closure
  • Financial assurance

28
Why do we have landfills?
  • Protect groundwater
  • Protect surface water
  • Protect air quality
  • Control pathogenic migration

29
Landfill Design
  • The main waste contaminant features are
  • Underlying soils
  • Depth to groundwater
  • Landfill liner (triple liner)
  • Leachate collection system
  • Leachate prevention through infiltration and
    drainage control
  • Cover soil and final landfill cap

30
The Size of the Landfill
  • Limit of Refuse filing (LRF) determines the
    volume of waste that can be properly stored at
    the site
  • Determined by site characterization, proximity to
    surface and groundwater

31
The Liner
  • A liner acts like a giant garbage bag
  • Clay liner
  • Synthetic liner
  • Additional liner

32
Liner Construction
33
Drainage Control
  • Surface water infiltration is drained from the
    landfill

34
Leachate
  • Leachate is the liquid that migrates from within
    a land disposal site which has come in contact
    with solid waste.

35
Monitoring
  • Groundwater monitoring wells are installed around
    the landfill to monitor pollution migration.
  • Gas collection wells are installed to remove
    methane which is a natural decomposition product
    or organic material.

36
Procedures
  • Waste is broken down and moved into the landfill.
  • A layer of dirt is used to cover the waste.

37
Closure
  • Solid waste is layered with soil or clay and
    capped off.

38
Closure
39
Landfill Construction
40
BURNING AND BURYING SOLID WASTE
  • Globally, MSW is burned in over 1,000 large
    waste-to-energy incinerators, which boil water to
    make steam for heating water, or space, or for
    production of electricity.
  • Japan and a few European countries incinerate
    most of their MSW.

41
Burning Solid Waste
  • Waste-to-energy incinerator with pollution
    controls that burns mixed solid waste.

Figure 22-10
42
Landfills can produce gas for energy
  • Bacteria can decompose waste in an
    oxygen-deficient environment
  • Landfill gas a mix of gases that consists of
    roughly half methane
  • Can be collected, processed, and used like
    natural gas
  • When not used commercially, landfill gas is
    burned off in flares to reduce odors and
    greenhouse emissions

43
THE RS
44
Solutions Reducing Solid Waste
  • Refuse to buy items that we really dont need.
  • Reduce consume less and live a simpler and less
    stressful life by practicing simplicity.
  • Reuse rely more on items that can be used over
    and over.
  • Repurpose use something for another purpose
    instead of throwing it away.
  • Recycle paper, glass, cans, plasticsand buy
    items made from recycled materials.

45
REUSE
  • Reusing products is an important way to reduce
    resource use, waste, and pollution in developed
    countries.
  • Reusing can be hazardous in developing countries
    for poor who scavenge in open dumps.
  • They can be exposed to toxins or infectious
    diseases.

46
Case Study Using Refillable Containers
  • Refilling and reusing containers uses fewer
    resources and less energy, produces less waste,
    saves money, and creates jobs.
  • In Denmark and Canadas Price Edwards Island
    there is a ban on all beverage containers that
    cannot be reused.
  • In Finland 95 of soft drink and alcoholic
    beverages are refillable (Germany 75).

47
REUSE
  • Reducing resource waste energy consumption for
    different types of 350-ml (12-oz) beverage
    containers.

Figure 22-7
48
Solutions Other Ways to Reuse Things
  • We can use reusable shopping bags, food
    containers, and shipping pallets, and borrow
    tools from tool libraries.
  • Many countries in Europe and Asia charge shoppers
    for plastic bags.

49
RECYCLING
  • Primary (closed loop) recycling materials are
    turned into new products of the same type.
  • Secondary recycling materials are converted into
    different products.
  • Used tires shredded and converted into rubberized
    road surface.
  • Newspapers transformed into cellulose insulation.

50
RECYCLING
  • There is a disagreement over whether to mix urban
    wastes and send them to centralized resource
    recovery plants or to sort recyclables for
    collection and sale to manufacturers as raw
    materials.
  • To promote separation of wastes, 4,000
    communities in the U.S. have implemented
    pay-as-you-throw or fee-per-bag waste collection
    systems.

51
RECYCLING
  • Composting biodegradable organic waste mimics
    nature by recycling plant nutrients to the soil.
  • Recycling paper has a number of environmental
    (reduction in pollution and deforestation, less
    energy expenditure) and economic benefits and is
    easy to do.

52
RECYCLING
  • Recycling many plastics is chemically and
    economically difficult.
  • Many plastics are hard to isolate from other
    wastes.
  • Recovering individual plastic resins does not
    yield much material.
  • The cost of virgin plastic resins in low than
    recycled resins due to low fossil fuel costs.
  • There are new technologies that are making
    plastics biodegradable.

53
RECYCLING
  • Reuse and recycling are hindered by prices of
    goods that do not reflect their harmful
    environmental impacts, too few government
    subsidies and tax breaks, and price fluctuations.

54
Alternatives
  • What can you do with waste other than landfilling
    it?
  • Compost piles
  • Biodegradable

55
Compost
  • Compost is a pile of organic debris.
  • Roughly half of household waste is made up of
    food and garden waste. Most of this material
    could be composted to save landfill, improve soil
    condition and provide fertiliser in the garden at
    no cost.
  • Composting is the method of breaking down waste
    organic materials in a large container or heap.
    The decomposition occurs because of the naturally
    occurring micro-organisms, such as bacteria and
    fungi.

56
Compost Piles
Can go in Compost Can't go in Compost
Vegetable and fruit scraps Meat and Dairy products
Fallen Leaves Diseased Plants
Tea Leaves and Tea Bags Metals, plastic glass
Coffee Grounds Droppings of meat eating animals (eg dogs)
Vacuum Cleaner Dust Fats or Oils
Soft Stems Magazines
Dead Flowers Large Branches
Used Vegetable Cooking Oil Weeds that have seeds or underground stems
Egg Shells Bread or cake (attracts mice)
Lawn Clippings Bones
Old Newspapers
Sawdust (not from treated timber)
57
Hazardous Waste
  • The rules are different!

58
Illegal dumping of hazardous waste
  • Since hazardous waste disposal is costly, it
    results in illegal and anonymous dumping by
    companies,
  • Creating health risks
  • Industrial nations illegally dump in developing
    nations
  • Basel Convention, an international treaty, should
    prevent dumping but it still happens
  • High costs of disposal encourages companies to
    invest in reducing their hazardous waste

59
Superfund
  • Later laws charged the EPA with cleaning up
    brownfields lands whose reuse or development
    are complicated by the presence of hazardous
    materials
  • Two events spurred creation of Superfund
    legislation
  • In Love Canal, Niagara Falls, New York, families
    were evacuated after buried toxic chemicals rose
    to the surface, contaminating homes and an
    elementary school
  • In Times Beach, Missouri, the entire town was
    evacuated after being contaminated with dioxin
    from waste oil sprayed on roads

60
The Superfund process
  • Once a Superfund site is identified, EPA
    scientists evaluate
  • How close the site is to human habitation
  • Whether wastes are currently confined or likely
    to spread
  • Whether the site threatens drinking water supplies

61
Superfund harmful sites
  • Harmful sites are
  • Placed on the EPAs National Priority List
  • Ranked according to the level of risk to human
    health that they pose
  • Cleaned up on a site-by-site basis as funds are
    available
  • The EPA is required to hold public hearings and
    inform area residents of tits findings and to
    receive feedback

62
Who pays for cleanup?
  • CERCLA operates under the polluter pays principle
    polluting parties were to be charged for
    cleanup
  • However, the responsible parties often cant be
    found
  • A trust fund was established by a federal tax on
    petroleum and chemical industries
  • The fund is bankrupt, and neither the Bush
    administration nor Congress has moved to restore
    it, so taxpayers now pay all costs of cleanup
  • Fewer cleanups are being completed
  • An average cleanup costs 25 million and takes 12
    - 15 years

63
Hazardous Waste Regulations in the United States
  • Two major federal laws regulate the management
    and disposal of hazardous waste in the U.S.
  • Resource Conservation and Recovery Act (RCRA)
  • Cradle-to-the-grave system to keep track waste.
  • Comprehensive Environmental Response,
    Compensation, and Liability Act (CERCLA)
  • Commonly known as Superfund program.

64
Hazardous Waste Regulations in the United States
  • The Superfund law was designed to have polluters
    pay for cleaning up abandoned hazardous waste
    sites.
  • Only 70 of the cleanup costs have come from the
    polluters, the rest comes from a trust fund
    financed until 1995 by taxes on chemical raw
    materials and oil.

65
The stepwise process of determining a hazardous
waste
  • Define the material as a waste
  • Define the waste as solid waste
  • Determine any solid waste exclusions
  • Define the solid waste as hazardous
  • Determine any hazardous waste exclusions

66
Hazardous Waste
  • Solid waste or combination of solid wastes which
    because of its quantity, concentration, or
    physical, chemical or infectious characteristics
    may cause an increase in mortality,
    incapacitating illness or pose a present or
    potential hazard to the health or environment
    when improperly treated, stored or disposed of.

67
A Hazardous Waste is . . .
  • listed by 40 CFR Part 261 or
  • is characterized by analytical methodology

68
EPA Criteria for Hazardous Waste
  • Toxicity
  • Persistence in the environment
  • Degradability in the environment
  • Bioaccumulation potential
  • Hazardous Characteristics ignitibility,
    corrosivity, reactivity, Toxicity Characteristic
    Leachate Procedure (TCLP)

69
Hazardous Characteristics
  • Ignitibility flashpoint less than 140oF
    (lt140oF)
  • Corrosivity pH less than 2.0 S.U. or greater
    than 12.5 S.U. (2.0 lt S.U. lt 12.5)
  • Reactivity a combination of greater than 250
    mg/kg of HCN and greater than 500 mg/kg of H2S

70
Hazardous Characteristics (cont.)
  • TCLP with one or more compounds above the Maximum
    Concentration Limit

71
Hazardous Waste Exclusions
  • Household waste
  • Agricultural waste returned as fertilizer
  • Mining overburden returned to mine site
  • Certain utility wastes from coal combustion
  • Certain oil natural gas exploration drilling
    waste

72
Hazardous Waste Exclusions (continued)
  • Waste from mining and processing ores
  • Cement chromium bearing wastes
  • Cement kiln dust wastes
  • Arsenic-treated wood wastes from end users

73
Dioxins
  • Regulated by TSCA
  • Group of more than 70 different chlorinated
    dioxins
  • By-product of certain manufacturing processes
  • Carcinogen
  • Teratogen
  • Mutagen

74
Bioaccumulators
  • Chlorinated Insecticides
  • Carbamates
  • Organophosphates
  • Herbicides
  • Metals

75
Hydrogen Sulfide
  • Decomposition product of organic matter
  • Sludge press by-product
  • If the pH falls below 7 S.U., Hydrogen Sulfide is
    released
  • Toxic gas

76
Cyanides (-CN)
  • Commonly found in plating operations and sludges
  • When mixed with an acid, Hydrogen Cyanide gas is
    released
  • Can cause instantaneous death
  • Acutely toxic

77
Eight Heavy Metals (RCRA)
  • Arsenic
  • Barium
  • Cadmium
  • Chromium
  • Lead
  • Mercury
  • Selenium
  • Silver

78
Case Study Lead
  • Lead is especially harmful to children and is
    still used in leaded gasoline and household
    paints in about 100 countries.

Figure 22-24
79
Case Study Mercury
  • Mercury is released into the environment mostly
    by burning coal and incinerating wastes and can
    build to high levels in some types of fish.

Figure 22-26
80

AIR
PRECIPITATION
PRECIPITATION
WINDS
WINDS
Hg2 and acids
Hg2 and acids
Hg and SO2
Photo- chemical
Elemental mercury vapor (Hg)
Inorganic mercury and acids (Hg2)
Human sources
Inorganic mercury and acids (Hg2)
Coal- burning plant
Incinerator
Deposition
Runoff of Hg2 and acids
Deposition
WATER
Large fish
Vaporization
BIOMAGNIFICATION IN FOOD CHAIN
Deposition
Small fish
Deposition
Zooplankton
Phytoplankton
Bacteria and acids
Oxidation
Organic mercury (CH3Hg)
Inorganic mercury (Hg2)
Elemental mercury liquid (Hg)
Bacteria
Settles out
Settles out
Settles out
SEDIMENT
Fig. 22-25, p. 542
81
Polychlorinated Biphenyls (PCBs)
  • Group of chlorinated hydrocarbons
  • Arochlor 1016, 1254, etc.
  • By-product of certain manufacturing processes
  • Transformer oil - dielectric properties

82
Waste Minimization
  • Waste minimization is required by all Large
    Quantity Generators and can be achieved by
  • using an alternative process
  • reducing the amount used or
  • solvent substitution

83
How is hazardous waste treated?
  • The EPA decides the appropriate method of
    disposal for each listed and typed waste.
  • Treatment, Storage and Disposal Facilities (TSDF)
    are permitted to handle hazardous waste.
  • Transporters of hazardous waste are also
    permitted.

84
Treatment Methods
  • There are several categories of treatment
    options.
  • Landfill or Storage
  • Incineration or Destruction
  • Fuel Blending
  • Neutralization
  • Biological Treatment

85
Conversion to Less Hazardous Substances
  • Incineration heating many types of hazardous
    waste to high temperatures up to 2000 C in
    an incinerator can break them down and convert
    them to less harmful or harmless chemicals.

86
Conversion to Less Hazardous Substances
  • Plasma Torch passing electrical current through
    gas to generate an electric arc and very high
    temperatures can create plasma.
  • The plasma process can be carried out in a torch
    which can decompose liquid or solid hazardous
    organic material.

87
Long-Term Storage of Hazardous Waste
  • Hazardous waste can be disposed of on or
    underneath the earths surface, but without
    proper design and care this can pollute the air
    and water.
  • Deep-well disposal liquid hazardous wastes are
    pumped under pressure into dry porous rock far
    beneath aquifers.
  • Surface impoundments excavated depressions such
    as ponds, pits, or lagoons into which liners are
    placed and liquid hazardous wastes are stored.

88

Trade-Offs
Deep Underground Wells
Advantages
Disadvantages
Leaks or spills at surface
Safe method if sites are chosen carefully
Leaks from corrosion of well casing
Wastes can be retrieved if problems develop
Existing fractures or earthquakes can allow
wastes to escape into groundwater
Easy to do
Encourages waste production
Low cost
Fig. 22-20, p. 539
89

Trade-Offs
Surface Impoundments
Advantages
Disadvantages
Groundwater contamination from leaking liners (or
no lining)
Low construction costs
Low operating costs
Air pollution from volatile organic compounds
Can be built quickly
Overflow from flooding
Wastes can be retrieved if necessary
Disruption and leakage from earthquakes
Can store wastes indefinitely with secure double
liners
Promotes waste production
Fig. 22-21, p. 539
90
Long-Term Storage of Hazardous Waste
  • Long-Term Retrievable Storage Some highly toxic
    materials cannot be detoxified or destroyed.
    Metal drums are used to stored them in areas that
    can be inspected and retrieved.
  • Secure Landfills Sometimes hazardous waste are
    put into drums and buried in carefully designed
    and monitored sites.

91
Secure Hazardous Waste Landfill
  • In the U.S. there are only 23 commercial
    hazardous waste landfills.

Figure 22-22
92
Brownfields
  • Brownfields are real property, the expansion,
    redevelopment, or reuse of which may be
    complicated by the presence or potential presence
    of a hazardous substance, pollutant, or
    contaminant.
  • In other words, an abandoned property that is
    potentially contaminated

93
How many?
  • It is estimated that there are more than 450,000
    brownfields in the U.S.
  • Cleaning up and reinvesting in these properties
    increases local tax bases, facilitates job
    growth, utilizes existing infrastructure, takes
    development pressures off of undeveloped, open
    land, and both improves and protects the
    environment.

94
Phytoremediation
  • Phytoremediation is the use of living green
    plants for in situ risk reduction and/or removal
    of contaminants from contaminated soil, water,
    sediments, and air.

95
Phytoremediation
  • Phytoremediation is actually a term for several
    ways in which plants can be used to clean up
    contaminated soils and water.
  • Phytoextraction or inorganics or metals
  • Rhizofiltration for metals
  • Phytostabilization to stabilize soil
  • Phytodegradation of organic compounds
  • Rhizodegradation for organics
  • Phytovolatilization

96
Advantages of phytoremediation
  • It is more economically viable using the same
    tools and supplies as agriculture
  • It is less disruptive to the environment and does
    not involve waiting for new plant communities to
    recolonize the site
  • Disposal sites are not needed
  • It is more likely to be accepted by the public as
    it is more aesthetically pleasing then
    traditional methods
  • It avoids excavation and transport of polluted
    media thus reducing the risk of spreading the
    contamination
  • It has the potential to treat sites polluted with
    more than one type of pollutant

97
Disadvantages of phytoremediation
  • It is dependant on the growing conditions
    required by the plant (ie climate, geology,
    altitude, temperature)
  • Large scale operations require access to
    agricultural equipment and knowledge
  • Success is dependant on the tolerance of the
    plant to the pollutant
  • Contaminants collected in senescing tissues may
    be released back into the environment in autumn
  • Contaminants may be collected in woody tissues
    used as fuel
  • Time taken to remediate sites far exceeds that of
    other technologies
  • Contaminant solubility may be increased leading
    to greater environmental damage and the
    possibility of leaching

98
  • http//arabidopsis.info/students/dom/mainpage.html

99
ACHIEVING A LOW-WASTE SOCIETY
  • In the U.S., citizens have kept large numbers of
    incinerators, landfills, and hazardous waste
    treatment plants from being built in their local
    areas.
  • Environmental justice means that everyone is
    entitled to protection from environmental hazards
    without discrimination.

100
Global Outlook International Action to Reduce
Hazardous Waste
  • An international treaty calls for phasing out the
    use of harmful persistent organic pollutants
    (POPs).
  • POPs are insoluble in water and soluble in fat.
  • Nearly every person on earth has detectable
    levels of POPs in their blood.
  • The U.S has not ratified this treaty.

101
Making the Transition to a Low-Waste Society A
New Vision
  • Everything is connected.
  • There is no away for the wastes we produce.
  • Dilution is not always the solution to pollution.
  • The best and cheapest way to deal with wastes are
    reduction and pollution prevention.
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