Solid, Hazardous, and Toxic
Waste
RHHS
Environmental Sciences
Mr. Bhatia
pp.529-548
Solid Waste
• What constitutes as Solid Waste?
• Any unwanted or discarded material that is
not liquid or a gas.
Which piece of the pie?
Municipal 1.5%
Industry Sewage 1%
9.5%
Agriculture Mining and oil
13% Agriculture
Industry
Municipal
Mining and oil
And gas production
Sewage
75%
Waste Stream
• Paper, 38%
• Yard Waste, 17%
• Metals, 8%
• Plastics, 8%
• Glass, 7%
• Food, 7%
• Miscellaneous, 14%
Municipal Solid Waste
• This waste is produced from homes and
businesses in or near urban areas.
• Municipal waste is called garbage.
• Over 200 BILLION TONS a year!
• United States leads the other five
countries:
• Australia, Canada, Switzerland, France,
and Norway
Waste Stream
• Waste stream is a term to describe the
entire life cycle of the garbage we all
produce.
• This includes garbage and yard wastes to
industrial, commercial, and construction
waste.
• THE CYCLE:
• Starts from putting the trash and recycling
for pickup to landfilling, energy production
and the reuse of recycled materials.
Lets Follow the Journey!
• Recycle
• Materials you recycle go to the Recycling
Facility
• Disposal
• Materials you place in the trash go to
Waste-To-Energy (energy recovery)
Facility
Recycling Facility
• Collection trucks unload the garbage onto
a “tipping floor”.
• From the tipping floor, recyclables are
placed on conveyor belts where they are
sorted by machines or hand.
• Sorted out into Paper, Plastic, glass, and
metal.
Are we REALLY getting
rid of the trash?
• Collecting and dumping processes mix and
crush everything together.
Making separation an expensive and
sometimes impossible task.
Value of recyclable materials are lost due
to incinerators.
• Hazardous materials in the waste gets
mixed in as well.
Waste Disposal Methods
• Open Dumps
• Ocean Dumping
• Landfills
• Exporting Wastes
• Incineration (energy recovery)
Open Dumps
• Least desirable but most commonly used
• Waste is left in giant piles, exposed to
wind and rain.
• Mostly present in under developed
countries.
• Illegal dumping sites still exists in
developed countries.
Ocean Dumping
• Every year, about 55 million pounds of
packaging, bottles, cans, and plastic
containers are dumped at sea.
• Many cities in the US dump municipal
waste sewage sludge in the ocean.
• New York City was the last to stop
offshore sewage sludge disposal in 1992.
Landfills
• Preferable than compared to open dumps
and ocean dumping.
• This is more of a regulated and controlled
method for waste disposal.
• Landfill operators are required to compact
the refuse and cover it everyday with a
layer of dirt.
• Benefit: Methane recovery
Methane or natural gas is a natural
product of decomposing garbage. It is a
great “Greenhouse Gas”.
Landfills (continued)
• Since 1995, all landfills in the US are
required to control hazardous substances
as oil, chemical compounds toxic metals
and rainwater that seeps through piles of
dirt.
• The US spends $10 Billion per year to
dispose trash. It may cost $100 Billion a
decade from now!
Exporting Wastes
• Taking hazardous wastes from your
country and exporting it to another place.
• Most industrialized nations in the world
have agreed to stop shipping hazardous
and toxic wastes to less developed
countries.
• However… this still continues!
Exporting wastes (continues)
• In 1999, over 3,000 tons of incinerated
waste was shipped from a plastic factory
in Taiwan and was unloaded and dumped
in a field near a small village in
Cambodia.
• US trying to take advantage of Indian
Reservations for dumping sites.
• Recycling the toxic waste into asphalt and
fertilizer.
Incinerators
• This is also known as energy recovery or
waste-to-energy
Incinerators
• Landfills are still the preferred method of
dumping waste.
• However, they are running out of room
and the expenses are rising.
• The newest method is burning waste.
• This is also known as energy recovery or
waste-to-energy
Heat is derived from incinerator and turned
into a useful source.
Incinerators (continued)
• Burning garbage helps produce steam
used directly to heat buildings and
generate electricity.
70
60
50
40
Recycled
30 Incinerated
20 Landfilled
10
0
Japan United
States
• Well over 1,000 waste-to-energy plants in
Brazil, Japan, and western Europe,
generate much needed energy while also
reducing the amount that needs to be
landfilled
Types of Incinerators
• There are two types of Incinerators:
• Refuse-derived fuel:
Waste is sorted to remove unburnable or
recyclable before combustion.
• Mass burn
The waste is not sorted out, instead
everything smaller than sofas and
refrigerators are placed into the furnace.
Pros and Cons
Incinerators
• Refuse-derived fuel is better for the
environment since there is removal of recyclable
materials, however; it is more costly having to
sort things out.
• Mass burn saves the cost in having not to sort
things, however; it causes more air pollution and
corrosion of burner gates and chimneys.
• In either case, there is a residual ash and
unburnable residues that need to be disposed of
properly.
Incinerator
Cost and Safety
• Cost wise, incinerators may be more
beneficial in the long run compared to
landfill rates that are sure to rise.
• Environmental Protection Agency (EPA)
has found high levels of toxic materials in
the ash recovered from incinerators.
For or Against?
• Believers for incinerators say that if the
incinerators are run properly, and
equipped with appropriate pollution-control
devices, these are safe to the public.
• Opponents counter this by stating
incinerators will effect the air pollution and
the better way to deal with waste is to
recycle and source reduce.
Debate between the class
• Each student has an index card that list if
the individual is FOR or AGAINST having
an incinerator built in their town.
• You can use the information from the
textbook, internet, the videos, power point,
and your own personal opinion.
Exit Pass
• What two ways of disposing wastes in an
incinerator?
Shrinking the Waste Stream
• Recycling
• Composting
• Energy from waste
• Demanufacturing
• Reuse
• Producing less waste
Recycling
• Recycling: Reprocessing of discarded
materials into new useful products
• Example: aluminum cans and glass bottles
melted down to be formed into new cans
and bottles.
• Turning old materials into entirely new
products.
• Old tires shredded and turned into
rubberized road surfacing.
Recycling (continue)
• About two thirds of aluminum cans are
recycled. Ex: about half of the cans on
grocery shelves will be made into another
can within two months.
• Recycling helps save money, energy, raw
materials and land space while reducing
pollution.
• It also reduces energy consumption and
air pollution.
Composting
• Composting: Biological degradation or
break down of organic matter under
aerobic (oxygen rich conditions).
• This process makes a nutrient rich soil that
aids water retention, slow soil erosion, and
improves crop yields.
Energy from waste
• Every year we throw away the energy equivalent
of 80 million barrels of oil in organic wastes in
the US.
• In a landfill the biodegradable materials are
decomposed by microorganisms generating
methane gas. This contributes to global warming
if allowed to escape into the atmosphere.
• By drilling in landfills and collecting the methane
gas, we are able to capture this vital form of
energy. Ex: fuel cells, gas and heat from animal
manure.
Demanufacturing
• Disassembly and recycling of obsolete
consumer products such as TV sets,
personal computers, washing machines
and air conditioners.
• EPA estimates that Americans dispose of
54 million household appliances every
year. Many of these products carry
valuable materials and also toxins that
must be kept out of the environment
Reuse
• Better than recycling or composting is cleaning
and reusing materials in their present form.
Thus saving the cost and energy into remaking
them into something else. Example: auto parts
are sold from junk yards, used materials from old
renovating houses.
• Reusing your containers is a GREAT IDEA!
Tell that to the big companies since they don’t
do this because it costs them more money.
Producing less waste
• Unnecessary wastes: this is created by excess
packaging for food and consumer products.
• This packaging is primarily for marketing
purposes and has little to do with protecting the
product from damages.
• Paper, plastic, glass, and metal packaging
material make up 50% of our domestic trash by
volume.
• What are some ways we can fix this issue of
excess packaging?
• Photodegradable plastics: breakdown when
exposed to ultraviolet radiation.
• Biodegradable plastics: incorporate such
materials such as corn starch that can be
decomposed by microorganisms.
• These two types of plastics don’t decompose
completely. They may leave small particles that
release toxic chemicals into the environment.
The three R’s
• Reduce, Reuse and Recycle.
• Recycle is the last “R” !
• We should pay close attention to reducing
and reusing first before recycling.
• What do you, family, and friends do on
daily basis that shows reducing or
reusing?
Hazardous Waste
• Hazardous waste is defined as : any
discarded soil or liquid material that
1. Contains one or more of the toxic
compounds, including solvents,
pesticides, and paint strippers
2. Catches fire easily
3. Reactive or unstable enough to explode
or release toxic fumes
4. Capable of corroding metal
Hazardous waste disposal
• Most hazardous waste is: Recycled,
converted into non-hazardous forms,
stored or otherwise disposed of.
• There are otherwise disposed of by the
generators: chemical companies,
petroleum refiners, and other large
industrial facilities.
• This way it doesn’t become a public
problem.
Federal Legislation
• Up until 1975, an estimated 5 million tons
of chemicals was improperly disposed of.
• There are two important federal laws that
regulate hazardous waste management
and disposal in the US.
Resource Conservation
and Recovery Act
• RCRA:
Created in 1976. This group performs an
intense program that requires extreme
testing and management of toxic and
hazardous substance.
A complex set of rules requires handlers of
these materials to record everything from
creation to the disposal.
Superfund Act
• The Comprehensive Environmental
Response Compensation and Liability Act
was passed in 1980.
• It was modified in 1984 and now called
Superfund Amendment and Reauthorization
Act (SARA).
• They aimed at rapid containment cleanup or
remediation of abandoned toxic waste sites.
SARA (continued)
• SARA allows the Environmental Protection
Agency (EPA) to take action incase there is a
threat of a toxic leak.
• SARA established the right for citizens to gain
access to information about their present
community.
• Toxic Release Inventory: requires 20,000
manufacturing facilities to report annually on
releases of more than 300 toxic materials.
Superfund sites
• EPA estimates that there are at least 36,000
seriously contaminated sites in the US.
• The General Accountability Office (GAO) says
that the number of contaminated sites is more
than 400,000 when all are identified.
• Superfund is an organization designed to:
1. Provide an immediate response to emergency
situations that leads to extreme hazards.
2. Clean up or take care of abandoned or inactive
sites
National Priority List
• For the NPL to have the site considered it
has to be especially hazardous for human
health and the environment.
• Top 10 substances of greatest concern:
• Lead, trichloroethylene, toluene, benzene,
PCBs, chloroform, phenol, arsenic,
cadmium, and chromium.
Characteristics of toxic sites
• Old industrial facilities and regions of the
country with high concentrations of aging
factories is where there are high
hazardous waste sites.
• Studies show that minorities are often
over-represented in the neighborhoods
with the most toxic release inventory sites.
CLEAN UP!
• 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 a brownfield for fear of the
cost it would take to cleanup. Even if it
was cleaned, no one wanted it.
• Owners of contaminated land complain
that the EPA is unreasonable.
Example: case of Columbia, Mississippi.
Options for Hazardous
Waste Management
• What can we do with toxic wastes?
• How can we reduce the waste generated
from these toxic materials we find at
home?
Producing Less Waste
• Support companies who use less energy and
fewer raw materials to produce their products.
• Recycling and reusing materials helps eliminate
hazardous waste and pollution.
• Double Savings Effect!
The generator doesn’t have to pay for disposing
of wastes, instead it gives or exchanges the
waste to another company so it can use it as raw
materials.
Converting less hazardous
substances
1. Physical treatments – Helps isolate the
substances.
• Example: Charcoal or resin filters absorb
toxins
• Example: Distillation separates toxic
components from many solutions
Converting less hazardous
substances (continue)
2. Incineration waste must be heated over
1000 degrees Celsius for a period of time
to complete destruction.
3. Chemical processing: helps transform
material so they become non-toxic
4. Bioremediation- Treatment that uses
microorganisms to absorb and detoxify a
variety of toxic compounds
Store Permanently
• Retrievable Storage- Placing waste
storage containers in a secure building,
salt mine, or bedrock cavern.
• Secure landfills- created for disposing of
many hazardous wastes.