Chapter_21_Presentation[1]

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Chapter 21:
Solid, Toxic and Hazardous Waste
Brita Christensen and Carlye Richter
Case Study: South Africa’s
“National Flower”
-Some South Africans began referring
to plastic bags as the country’s
national flower
-Each year shops hand out 8 billion
light-weight, single-use bags
-If they were thicker (80 microns)
they would be reusable and litter
would be reduced
-Trade unions fear that current
machines wouldn’t be able to make
such bags, causing unemployment
-If the bags were thicker, stores
would charge more for them, making
customers more likely to reuse
Solid Waste
 The U.S. produces 11
billion tons per year
 ½ is agricultural waste
 1/3 of all solid wastes are
produced from mining
and primary metal
processing
 Road and building
construction debris
 Improper disposal methods
spread waste
 Industrial waste is 400
million metric tons a year
 60 million of these are
hazardous or toxic waste
 Municipal waste is 200
million + metric tons a year
 2/3 of a ton per person
Question!
How many tons of solid
waste does the U.S.
produce every year!?
The Waste Stream
 Definition: the steady
flow of varied wastes that
we all produce, from
domestic garbage and
yard wastes to industrial,
commercial and
construction refuse.
 Most of this waste could
be valuable if it wasn’t
mixed
 Hazardous materials
spread through garbage
making disposal
processes more difficult,
expensive and risky
 Examples of potentially
hazardous trash: spray
paint cans, pesticides,
batteries, cleaning
solvents, dioxin releasing
plastics
Question!
What is one example of
potentially hazardous
trash!?
Waste Disposal
Methods
Open Dumps Release
Hazardous Materials Into Air
and Water
--The Three “R’s”
Toxic chemicals are
showing up in
groundwater supplies that
½ of America depends on
for drinking
-Theoretically, one liter of
gasoline could make a
million liters of water
undrinkable
 Open, unregulated dumps
are predominant in most
developing countries
 Mexico City produces 10,000
tons of trash a day
 Manila, Philippines –half of
their waste collects in
“Smoky Mountain” -20,000
people live and work there
 Open dumping has been
banned in most places, but
illegal dumping is still a
problem
 200 million L of motor oil are
illegally dumped a year –5
times the amount spilled
from Exxon Valdez, 1989
Ocean Dumping is Nearly
Uncontrollable
-25,000 metric tons (55
million lbs.) of packaging a
year are dumped at sea.
-Federal legislation
prohibits dumping of
municipal refuse, industrial
waste, sewage and sewage
sludge in the ocean
-60-80 million m3 of dredge
spoil are disposed of at
sea.
Landfills Receive Most
of Our Waste
-Sanitary landfills are an alternative to
open dumps
-This method regulates and controls
solid waste disposal
-landfill operators are required to
compact the refuse and cover it with
a layer of dirt, this controls pollution
but also takes up 20% of landfill space
-An impermeable clay and/or plastic
lining underlies and encloses the
storage area in landfills
-Drainage systems surrounding the
liner catch drainage and monitor
chemicals that may be leaking
-location is essential to landfills,
demonstrating concern for long-term
effects associated with this form of
disposal
Question!
What is an alternative to open
dumps!?
More on Landfills …
-The U.S. spends $10 billion a year
to dispose of trash
-1,200 of the 1,500 existing
landfills in the U.S. have closed
since stricter financial and
environmental protection
requirements for landfills took
effect in 1984
-Cities have begun exporting
trash which is expensive
-Methane –an important GHG is
important to recover.
-It seeps to the surface of a
landfill and escapes, but now it is
collected and burned.
-Landfills could provide enough
electricity for a city of a million
people
Question!
How much money does the
U.S spend per year on
disposing of trash!?
Exporting Waste Exposes Villagers to Hazards
 Most industrialized nations have agreed to stop
shipping hazardous and toxic waste to less-developed
countries
 The Taiwan village disaster
 Poor neighborhoods and minority populations are
much more likely than richer ones to be the recipients
of dumps, waste incinerators, and other locally
unwanted land uses (LULUs)
 One method of disposing of toxic wastes is to recycle
them
 Manufacturers are now required to report the
“active” ingredient content of their product, but
much can go unreported as “inert” matter
Incineration Produces Energy but
Causes Pollution





Burning serves as an alternative to landfills
Energy-recovery
Refuse-derived fuel
Mass burn
Incinerators are costly, but can also extend the lifetime of
existing landfills
 EPA found high levels of toxic substances in incinerator ash
–more in the fly ash than others
 EPA says the danger is small, and causes 1 death per million
people every 70 years, though critics claim it to be 250 per
million
 To reduce dangers, remove batteries containing heavy
metals and plastics containing chlorine before incineration
(eliminates majority of dioxins and other by-products)
Question!
What is one advantage of
incinerators?
Shrinking the Waste Stream
• Recycling means reusing, but also reprocessing
• One problem for recyclers is the fluctuation in market prices
for commodities
• Another problem is contamination (ex: soda bottles)
• Plastic recycling is down 50% due to “on the go” packaging
• Recycling is the best alternative because it saves money,
energy, raw materials, and land space
• Encourages individual awareness and responsibility
• Recycling has quadrupled since 1980, right now Japan is the
world’s leader, recycling ½ of it’s municipal waste
• When waste is well sorted, recycling is most successful
• Recycling reduces our need for raw resources
• Although public policy favors the use of raw material now,
government statutes are working to change that
Commercial-scale Recycling and
Composting
 Composting is the most common form of large-scale
recycling
 Cities and towns have begun providing compost
facilities to save landfill space
 Organic debris is 12% of our waste stream, and ½ of
organic waste is composted
 An increasing number of the thousands of tons of
debris sent to landfills is being collected, sorted and
resold
 Thermal conversion Process (TCP)
De-manufacturing
• Definition: the disassembly
and recycling of obsolete
products like TV sets,
computers, refrigerators and
air conditioners. Electronics
and appliances are one of the
fastest-growing components
of the global waste stream
• E-waste –computers, cell
phones, TVs and printers
• A single computer can contain
70 different chemical
compounds
• 40% of lead and 70% of heavy
metals come from e-waste
• Some nations have taken the
initiative in reducing these
environmental hazards
Question!
What is an example of Ewaste?
Reusing vs. Recycling
 Reusing is better than
recycling
 The reusable, refillable
bottle is the most efficient
beverage container we have
 Big companies prefer
recyclable containers over
reusable containers because
they are more cost efficient
 In some cases, reusing is not
energy efficient
 Where manufactured
products are expensive and
labor is cheap, it pays to
reuse
Question!
Which is better: reusing or
recycling?
Reducing Waste is Often the
Cheapest Option
• Excess packaging of food and consumer products is
one of our greatest sources of unnecessary waste
• Paper, plastic, glass and metal packaging material
make up 50% of our domestic trash by volume
• Most packaging is primarily for marketing purposes
• Canada’s National Packaging Protocol (NPP)
• 1) no packaging  2) minimal packaging  3) reusable
packaging  4) recyclable packaging
• -Photodegradable plastics
• Biodegradable plastics
• Both are compostable or degradable
• Sometimes materials don’t decompose completely
• The most effective way to save energy, materials, and
money is to slow the consumption of throwaway
products
Hazardous Waste Must be Recycled,
Contained or Detoxified
• Hazardous waste –any discarded material,
liquid or solid, that contains substances
known to be (1) fatal to humans or
laboratory animals in low doses (2) toxic,
carcinogenic, mutagenic, or teratogenicto
humans or other life-forms (3) ignitable
with a flash point less than 60 degrees
Celsius (4) corrosive or (5) explosive or
highly reactive
Most hazardous waste is recycled,
converted to nonhazardous forms, stored
or otherwise disposed of onsite by the
generators
5 billion metric tons of highly poisonous
chemicals were improperly disposed of in
the U.S. between 1950 and 1975
Hazardous and Toxic
Wastes
• The most dangerous aspect of the
waste stream is that it often
contains highly toxic and
hazardous materials that are
injurious to both human health
and environmental quality
• The EPA states that industries in
the U.S. generate about 265
million metric tons of officially
classified hazardous wastes each
year, slightly more than 1 ton for
each person in the country
• 40 million metric tons (22billion
lbs.) of toxic and hazardous
wastes are released into the air,
water, and land in the U.S. a year
Question!
Why is the waste stream so
dangerous?
Federal Legislation
• The Resource Conservation and
Recovery ACT of 2976
• The Comprehensive
Environmental Response,
Compensation and Liability Act
(CERCLA or Superfund ACT) of
1980 (modified in 1984 by the
Superfund Amendments and
Reauthorization Act (SARA))
• The Toxic Release Inventory
requires more 20,000
manufacturing facilities to report
annually on releases of more than
300 toxic materials
Superfund Sites are Those
Listed for Federal Cleanup
• The EPA estimates that there
are at least 36,000 seriously
contaminated sites in the U.S.
• The GAO says it’s higher
(400,000 +)
• By 1997 1,400 sites were on
the NPL (National Priority List)
for cleanup financed by the
federal Superfund program
• Superfund –a revolving pool
designed to (1) provide an
immediate response to
emergency situations that
pose imminent hazards and
(2) to clean up or remediate
abandoned or inactive sites
Case Study #2: Hardeman
County, Tennessee
• The chemical build up began when
William T. Love left his project of a
man-made canal unfinished
• Hooker Chemicals Corp. used this
as a landfill
• The runoff started emerging
throughout the community
• The seepage caused adverse
effects among community
members
• Some included: birth defects,
miscarriages, still births, cancers,
heart diseases, nervous system
defects and other health related
issues
• The tragedy was resolved only
after many activist efforts
Brownfields
 Large areas of contaminated properties that have been
abandoned or are not being used up to their potential
because of real or suspected pollution
 No one wanted to redevelop brownfields because of liability
Question!
Why does no one want to
redevelop brownfields?
Redeveloping Brownfields
 Reusing contaminated
properties can rebuild old
cities, create jobs, increase the
tax base, and prevent needless
destruction of open space at
urban margins
 Programs have been
established at the federal and
state levels to encourage
brownfield recycling
 Must pass EPA standards
What do we do with toxic and
hazardous wastes?
 Produce less waste!
 Modify manufacturing processes, recycle, and reuse material
 Convert to less hazardous substances! (several processes to
make hazardous materials less toxic)
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Physical treatments- tie up or isolate substances
Incineration- burning wastes
Chemical processing- transform materials into nontoxic
Bioremediation- uses microorganisms to absorb, accumulate, and
detoxify toxic compounds
What else do we do with toxic and
hazardous wastes?
 Store permanently!
 Permanent retrievable storage- placing waste storage
containers in a secure building, salt mine, or bedrock cavern
where they can be inspected periodically and retrieved for
repacking or for transfer
 Secure landfills- must be safe
 Thick bottom cushion of compacted clay
 Layer of gravel over the clay and drain pipes to collect
seepage
 Thick polyethylene liner
 Layer of soil or absorbent sand cushions
 Wastes packed in drums, separated into small units
Question!
What is one method of
disposing of hazardous
wastes?
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