Solid and Hazardous Wastes
In nature, there is essentially no wastes because the wastes
of one organism become the nutrients for another. This
recycling of nutrients is the basis for one of the scientific
principles of sustainability.
Humans produce large amounts of wastes that go
unused and pollute the environment.
Categories of wastes
Solid waste: any unwanted or discarded material we produce that is not a liquid or gas.
Municipal solid waste (MSW): produce directly from homes and workplaces,
containing a mix of paper, food, cans bottles etc. Referred to as trash or garbage.
The top four contributors to MSW in order by weight are: Paper, yard waste,
food waste, and plastics.
Industrial solid waste: produced by mines, agriculture and industries that supply
people with goods and services. Ex: empty chemical containers, ash, tires and
many of the things above.
Hazardous (toxic) waste:
threatens human health or
the environment because it is
toxic, chemically active,
corrosive or flammable. Ex:
Industrial solvents, medical
waste, car batteries, and
pesticides. There are three
categories:
Organic compounds: Solvents,
pesticides, and dioxins.
Toxic heavy metals: Lead,
mercury, cadmium, Chromine
and arsenic.
Highly radioactive waste
produced by nuclear power
plants and weapons facilities
must be stored safely for
10,00 to 240,000 years
depending on the half-life of
the material.
Hazardous or Toxic Waste
Why Reduce Solid and Hazards Wastes?
According to the U.N. environmental Programme (UNEP) developed counties produce 80-90% of
all hazardous waste. Currently the U.S. is the biggest contributor with China catching.
Three fourths of the materials we dispose of represents an unnecessary waste of the Earth’s
resources. We can recycle or reuse 90% of the produced MSW.
Countries collect, mix and bury MSW in
landfills. Once mixed they can mix with
hazards wastes or become too expensive
to recover and these resources are lost.
Countries burn MSW which pollutes the air
and leaves a toxic ash that must be buried.
So called pollution prevention causes rich
countries to move polluting industries to
poor countries.
Also making the products we use and then
discard creates large amounts of air, water
and land pollution.
Solid wastes polluting a river in Jakarta,
Indonesia. The man in the boat is looking for
items to salvage or sell.
Waste in the United States
The United States leads the world in producing solid waste. We produce about a third of the
world’s solid waste with only 4.6% of the worlds population. and buries more than half of it
in landfills.
About 98.5% is industrial solid waste.
Mining (76%), Agriculture (13%) and
industry (9.5%).
The remaining 1.5% is MSW.
About 54% of U.S. MSW is dumped
into landfills, 25% is recycled, 7% is
composted, and 14% is burned in
incinerators.
What do we throw away?
3,200 plastic shopping bags per second
Tires (enough to circle the planet 3 times per year) Carpet (enough to cover Delaware per year)
Diapers (reach the moon and back seven times) 2.5 billion plastic bottles per hour
The U.S. also leads the way in trash per person at 4.5 pounds of MSW per day. Recycling is
helping since 1990 the MSW per person has leveled off.
Electronics: Environmental Killers
E-waste consists of toxic and hazardous waste such
as PVC, lead, mercury, and cadmium.
Your computer uses 700 or more
materials obtained from mines, oil
wells and chemical factories.
For each pound of electronics 8000
pounds of solid and liquid waste is
produced. Producing the chips
produce 630 times its weight in solid
and hazards waste.
Extracting the resources and using
them require large amounts of
energy and burning fossil fuels
emitting CO2 and other pollutants
into the atmosphere.
The U.S. produces almost half of the world's ewaste but only recycles about 10% of it.
Integrated Waste Management
How should we deal with Solid waste?
1. Waste Management: The
attempt to reduce the
environmental impact of
MSW without trying to
reduce the amount of waste
produced.
The most common approach
is to mix MSW and burying
them, burning them or
shipping to another location.
2. Waste reduction: Produce
less waste and pollution. This
includes the three R’s: reduce,
reuse, and recycle.
Scientists call for using a variety of strategies to deal with MSW and hazardous waste described
as Integrated Waste Management with an emphasis on waste reduction.
Raw materials
Integrate Waste Management
Processing and
manufacturing
Products
Solid and hazardous wastes
generated during the
manufacturing process
Plastic Glass
Waste generated by
households and businesses
Metal Paper
To manufacturers for reuse or
for recycling
Food/yard waste
Compost
Hazardous
waste
Remaining mixed
waste
Hazardous waste
management
Landfill
Incinerator
Fertilizer
Fig. 21-5, p. 565
IWM’s Priorities
We Can Cut Solid Wastes by Following the R’s
Refuse: to buy items that we really don’t 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. 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 for items they can reuse or sell. They can be exposed to toxins or
infectious diseases.
Reusing items decreases the use of matter and energy resources and reduces pollution and
natural capital degradation; recycling does so to a lesser degree.
Repurpose: use something for another purpose instead of throwing it away.
Recycle: paper, glass, cans, plastics…and buy items made from recycled materials.
Recycling
Recycling: Conservation of resources by converting them into new
products. Recycling reduces unsightly and environmentally harmful
litter.
Households and workplaces produce 5 major types
of materials that can be recycled:
1. Paper
2. Glass
3. Aluminum
4. Steel
5. Some plastics
Materials can be recycled in two ways:
Primary (closed loop) recycling: materials are turned into new products of the
same type. Aluminum cans are turned into new aluminum cans.
Secondary recycling: materials are converted into different products.
Used tires shredded and converted into rubberized road surface.
Newspapers transformed into cellulose insulation.
Types of wastes that can be recycled
Preconsumer: internal waste from the manufacturing process (3/4)
Postconsumer: external waste from consumer use of products (1/4)
Recycling Paper
Recycling paper has a number of environmental (reduction in
pollution and deforestation, less energy expenditure) and
economic benefits and is easy to do. About 55% of trees are
harvested to make paper.
The internet was supposed to reduce paper use, however most
people still print out their searches and there is no drop in per
capita consumption in the United States.
Recycling paper uses 64% less energy, 35% less water
pollution and 74% less air pollution and no trees are cut
down. Recycling in done by removing ink, glue, coating and
converting it back to pulp.
U.S. currently recycles 56% of its paper and paperboard.
Despite this number the U.S. throws away more paper than is
used in all of China. Denmark, recycles about 97% of its
paper.
Problems: Many U.S. mills are not able to process waste paper. Many countries like Mexico,
import a large amount of wastepaper from the U.S. (19%). Bleaching paper with chlorine
compounds (Cl02) is bad for the environment. Solution: Replacement of chlorine-based
bleaching chemicals with H2O2 or O2
For example, the Sunday edition of the New York Times consumes 62,000 trees.
Recycling Glass and Aluminum
Glass: U.S. recycles about 36% of its glass
containers. It costs less to recycle glass than
to make new glass.
Mixed color glass is used for Glassphalt: a
variety of asphalt that uses crushed glass. It
has been used as an alternative to
conventional bituminous asphalt pavement
since the early 1970s. Glassphalt must be
properly mixed and placed if it is to meet
roadway pavement standards
Aluminum is the most recycled material in
the U.S. because of money gained by the
recycler. Making a new can from an old
one requires a fraction of the energy than
to make a new can from raw materials
(Aluminum ore).
Approximately 2/3 of cans are recycled each year, saving 19 million barrels of oil annually.
Recycling Plastic
Plastics: Large polymers or resins (organic
compounds) made from oil and natural gas.
Plastic containers are thrown into the
environment and end up by roads, beaches
and in water. They threaten seabirds,
marine mammals, and sea turtles that can
mistake a sandwich bag for a jellyfish or get
caught in plastic nets.
Currently only about 4% of plastic is recycled
in the United States.
Reasons plastic recycling is low
1. Many plastic resins are hard to isolate because containers are made of many different resins.
For example ketchup bottles are composed of six layers of resin.
2. Recovering resins does not yield much material
3. Cheaper to make new plastics than to recycle. The exception is PET.
Recycling PET and PVC
PET (Polyethylene terephthalate) is used to
make soft drink bottles, peanut butter jars,
etc. PET can be recycled into fiberfill for
sleeping bags, carpet fibers, rope, and
pillows at a cost efficient rate. Most
common recycled plastic.
PVC (Polyvinyl chloride) is used in shampoo
and cooking oil bottles & fast-food service
items. Advantage: Replaced lead pipes for a
lot of water services reducing lead
compounds in water.
Problems: If one PVC bottle is mixed in with
the PET, recycling is useless. This is why
there are markings on certain plastic bottles.
Recycling HDPE and LDPE
HDPE (High-density polyethylene) is found
in milk jugs, butter tubs, detergent bottles,
and motor oil bottles. HDPE can be recycled
into flowerpots, trashcans, traffic barrier
cones, and detergent bottles.
LDPE (Low-density polyethylene) is
found in grocery bags, bread bags,
shrink-wrap, and margarine tub tops.
LDPE can be recycled into new grocery
bags. Outlawing plastic grocery bags in
some counties is aimed to reduce this
waste.
Recycling PP and PS
PP (Polypropylene) is used in yogurt containers,
straws, pancake syrup bottles, and bottle caps. PP
can be recycled into plastic lumber, car battery
cases, and manhole steps.
PS (Polystyrene) is found in disposable hot cups,
packaging materials (peanuts), and meat trays. In
1941, Dow Chemical invented a Styrofoam
process. PS can be recycled into plastic lumber,
cassette tape boxes, and flowerpots.
Seven Strategies that Industries and
Communities can use to Reduce Resource use,
Waste and Pollution.
(1) Redesign manufacturing processes and products to use less material and energy.
Plastic bottles and aluminum cans use less materials than before.
(2) Redesign manufacturing processes to produce less waste and pollution. Developing
strategies in which waste from some businesses are raw materials for others.
(3) Develop products that are easy to repair, reuse, remanufacture, compost, or recycle
(4) Eliminate or reduce unnecessary packaging
(5) Use fee-per-bag waste collection systems. Charge consumers for the amount of waste they
throw away but provide free pick up for recyclable or reusable items.
(6) Establish cradle-to grave responsibility laws. Require companies to take back
consumer products such as electronic equipment, appliances and motor vehicles.
(7) Restructure urban transportation systems. Rely more on mass transit and bikes than
cars.
Burning Solid Waste
One of 600 global Waste-to-energy
incinerator with pollution controls that
burns mixed solid waste and turns it into
98 in the United States which burned 16% of the
steam that runs an electric producing
nation’s solid waste and produces less CO2 emissions
generator.
than power plants that run on fossil fuels.
Burying Solid Wastes: Landfills
Solid waste is placed in a hole, compacted, and covered with soil.
Covering it reduces the number of rats associated with solid waste, lessens the danger of
fire, and decreases the odor.
Open dumps are essentially holes in the ground where trash is dumped. They are rare in
developed countries.
Sanitary landfills: solid wastes are spread out in thin layers, compacted and covered daily
with a fresh layer of clay or plastic foam.
Topsoil
Sand
Clay
Garbage
Probes to
detect
methane
leaks
When landfill is full,
layers of soil and clay
seal in trash
Electricity
generator
Methane storage
building
Methane gas
recovery well
Pipes collect explosive methane
as used as fuel
to generate electricity
Leachate
storage
tank
Compacted
solid waste
Garbage
Sand
Synthetic
liner
Sand
Clay
Subsoil
Leachate
treatment system
and compressor
building
Leachate
pipes
Leachate pumped
up to storage tank
for safe disposal
Clay and plastic lining
to prevent leaks; pipes
collect leachate from
bottom of landfill
Groundwater
Groundwater
monitoring
well
Leachate
monitoring
well
Fig. 22-12, p. 532
Landfills: Current Criteria
Compacted clay and plastic sheets are at the bottom (prevents liquid waste from seeping into
groundwater) Currently landfills are the primary method of waste disposal in the United
States, with 54% ending up there.
A double liner system must be present (plastic, clay,
plastic, clay), and a system to collect leachate (liquid
that seeps through the solid waste)
Oil, Air Conditioner Coolants, Lead Acid (Car
Batteries) and Antifreeze: Not allowed. Must go to
an automotive or environmental company for
recycling.
Tires: Are usually allowed if they are
quartered or shredded.
According to the EPA, all landfills eventually leak, passing the effects of contamination and
cleanup costs on to future generations. Leachate is the most serious problem associated with
sanitary landfills.
How to Deal with Hazardous Wastes
Detoxifying Hazardous Wastes
Detoxifying hazardous wastes involves
converting them into less hazardous wastes.
Physical Methods: using charcoal or resins to separate out harmful chemicals. Deadly
wastes can be encapsulated in glass or cement and put in secure storage sites.
Chemical Methods: using chemical reactions that can convert hazardous chemicals to less
harmful or harmless chemicals.
Bioremediation: bacteria or enzymes help destroy toxic and
hazardous waste or convert them to more benign substances.
Phytoremediation: involves using natural or genetically engineered
plants to absorb, filter and remove contaminants from polluted soil
and water.
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.
Plasma Arc Torch: passing electrical current through gas to generate an electric arc and very
high temperatures can create plasma.
Radioactive
contaminants
Organic
contaminants
Inorganic
metal contaminants
Poplar tree
Sunflower
Willow tree
Brake fern
Indian mustard
Landfill
Polluted
groundwater in
Soil
Groundwater
Rhizofiltration
Roots of plants such as
sunflowers with dangling
roots on ponds or in greenhouses can absorb pollutants
such as radioactive strontium-90
and cesium-137 and various
organic chemicals.
Decontaminated
water out
Phytostabilization
Plants such as willow
trees and poplars can
absorb chemicals and
keep them from reaching
groundwater or nearby
surface water.
Oil
spill
Polluted
leachate
Phytodegradation
Plants such as poplars
can absorb toxic organic
chemicals and break
them down into less
harmful compounds
which they store or
release slowly into the air.
Soil
Groundwater
Phytoextraction
Roots of plants such as Indian
mustard and brake ferns can
absorb toxic metals such as
lead, arsenic, and others and
store them in their leaves.
Plants can then be recycled
or harvested and incinerated.
Long-Term Storage of Hazardous Waste
Ideally, burial on land or long-term
storage of hazardous and toxic
wastes should be used only as a
third resort after phytoremediation
and plasma torch arc. Currently
burial on land is the most widely
used method in the U.S.
Hazardous waste can be disposed
of on or underneath the earth’s
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. 64% of
all liquid hazardous wastes in the
U.S. are disposed of this way.
Surface impoundments: excavated depressions such as ponds, pits, or lagoons into which liners
are placed and liquid hazardous wastes are stored.
The EPA found that 70% of these storage basins in the U.S. have no liners, and up to 90% of
them may threaten groundwater. Eventually all liners will leak.
Surface Impoundment in Niagara Falls,
New York, U.S.
Long-Term Retrievable Storage:
Metal drums are used to stored
them in areas that can be
inspected and retrieved. This is
designed for materials like
mercury which cannot be
destroyed, detoxified or safely
buried.
Secure hazardous waste
landfills: Sometimes hazardous
waste are put into drums and
buried in carefully designed and
monitored sites.
In the U.S. there are only 23
commercial hazardous waste
landfills.
Mercury
Mercury is among a group of pollutants called
persistent bioaccumulative toxins or PBTs. These
pollutants "persist" in the environment, meaning
that they do not break down or go away. Mercury
cannot be destroyed, it cannot be combusted, and
it does not degrade. Mercury also
"bioacccumulates" in the environment, meaning it
builds up in the food chain over time.
Mercury can be released in the environment
from natural sources, such as volcanic and
geothermal activity, marine environments or
forest fires, or it can be released from
anthropogenic (man-made) sources like coal-fired
power plants and other industrial activities.
Recent studies suggest that human activity
contributes 50-70% of the mercury in the
environment globally. Once mercury enters the
environment, it circulates in and out of the
atmosphere until it ends up in the bottoms of
lakes and oceans.
Hazardous Waste Regulations in the
United States
Two major federal laws regulate the management and disposal of hazardous waste in the U.S.
The Resource Conservation and Recovery Act (RCRA) pronounced RICK-ra , enacted in 1976, is
the principal federal law in the United States governing the disposal of solid waste and
hazardous waste
Goals of RCRA:
1. Protecting human health and the natural environment from the potential hazards of waste
disposal.
2. Energy conservation and natural resources.
3. Reducing the amount of waste generated, through source reduction and recycling
4. Ensuring the management of waste in an environmentally sound manner.[2]
It is now most widely known for the regulations promulgated under RCRA that set standards for
the treatment, storage and disposal of hazardous waste in the United States.
Cradle-to-the-grave system to keep track waste.
Superfund is the common name for the Comprehensive Environmental Response,
Compensation, and Liability Act of 1980 (CERCLA), a United States federal law designed to clean
up sites contaminated with hazardous substances
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.
Pace of cleanup has slowed
Superfund is broke
Leaking Barrels of Toxic Waste at a Superfund Site in the
United States
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.
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. High number of birth defects were recorded fro the area.
President Jimmy Carter declared
Love Canal a federal disaster area.
The area was abandoned in 1980.
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.
Read section 21-6: know NIMBY, NIABY, NOPE, Environmental justice, Basel Convention, POPs,
The Dirty Dozen, Swedish Parliament, and Transitioning to a Low-Waste Society.