Chapter 21 and 22 Flashcards
In the 1970s and 1980s, what did closing old landfills create?
A “solid waste crisis” that turned out to be temporary
What have many old landfills been converted into?
parks, golf courses, nature preserves
Municipal solid waste (MSW)
total of all materials thrown away from homes and small businesses
Examples of msw
trash, refuse, garbage
Who collects MSW?
local governments
What is municipal solid waste different from?
hazardous waste and nonhazardous industrial waste
Nonhazardous industrial waste
generated by industries
Why is the amount of MSW generated in the U.S. increasing?
more people, changing lifestyles, excessive packaging
What was the average MSW in 1960?
2.7 lbs/person/day
What is the average MSW now?
4.4 lbs/person/day
Why is it hard to disose of MSW in an environmentally sound and healthy way?
we generage huge amounts of MSW
What percent of MSW composition is paper and cardbord?
32.7%
What percent of MSW composition is yard waste?
12.7%
Who pays for the cost of waste pickup?
collectors bill households (some towns completely leave it u to the private sector)
What do state and federal regulations begin to apply at?
disposal
What happened to MSW until the 1960s
it was burned and buried in dumps
smoldering dumps
smelled and attracted flies and rats
Incineration (combustion facilities)
burn waste completely
What does incineration cause?
air pollution
Why have landfills and combustion declinded in the last 10 years?
recycling has increased
What were open dumps replaced by?
landfills
Why were open dumps and incinerators phased out in the 1960s and 1970s?
public pressure and air pollution laws
Landfill
waste is put on or in the ground and covered with earth
What do landfills minimize?
air pollution andn vermin
Why did landfill managers not understand ecology, the water cycle, or products of decomposition?
they didn’t have regulations to guide them
Where were landfills put on?
any cheap land outside of town
Leaching
chemicals dissolve in and are transported by water
Leachate
water with various pollutants
What makes up leachate?
organic matter, heavy metals, chemicals
Why is leachate dangerous?
it can enter groundwater aquifers
Superfund list
sites where groundwater contamination threatens human health
What state has 145 sites on the Superfund list?
Florida
What supported the Superfund list?
Federal money
What made up 54% of MSW disposal?
Landfills
What made up 33.4% of MSW disposal?
Recycling
What made up 12.6% of MSW disposal?
Combustion
What does buried waste undergo?
anaerobic decomposition
What does buried waste that undergos anaerobic decomposition produce
biogas
Biogas
methane, CO2, hydrogen
An effect of biogas being highly flammable
they seep horizontally through soil, entering homes and causing explosions
Another problem with biogas
it kills vegetation
What can happen to biogas after they’re captured
they can be purified and used as fuel
What happened in 2008?
commercial landfill gas produced electricity and gas for 1.4 million homes
What do captured biogas reduce
greenhouse gas emissions and fossil fuel use
The landfill gas-to-energy project
will reduce annual greenhouse emissions by 40 million pounds of carbon dioxide by avoiding the use of fossil fuels
Methane from closed MA landfill being mined is used to do what?
generate electricity to power over 3,000 homes
Plastics in MSW
resist decomposition
Petroleum-based polymers
resist microbial digestion
What kind of polymers have been developed?
biodegradable plastic polymers
What happens to waste as it compacts and decomposes?
settles
What has never been put on landfills?
Buildings
What do landfills that have been converted to playgrounds and golf courses create?
Shallow depressions or deep holes
Where are new landfills sited on?
high, stable ground above the water table, away from airports
What does water drain into?
A leachate-collection system (and is treated)
What do tile plastic liners, and compacted soil collect?
Leachate, after which it will be treated
What do abandoned landfills become?
recreational facilities
Desirable consequences of siting problems
it encourages recycling and stimulates combustion of MSW
Fly ash
contains most of the toxic substances
What is fly ash a product of
incineration
Why can fly ash be disposed of?
if it is combined with water, then with bottom ash
Two-thirds of combustion facilites
are waste-to-energy (WTE)
What does WTE produce?
electricity for 2.3 million homes
Air pollution
has decreased through strict regulations
Odor pollution
plants are isolated from residential areas
Siting
facilities are located in industrial areas
Toxic ash
must be disposed of in secure landfills
Source reduction
reducing waste at its source
Examples of source reduction
designing, manufacturing, purchasing, or using materials to reduce the amount/toxicity of trash
What percent of MSW is recyclable
75%
Primary recycling
the waste is recycled into the same material
Secondary recycling
waste is made into different products that may or may not be recyclable
What makes up 64% of what gets recycled?
yard wastes
What makes up 47% of what gets recycled?
paper, cardboard, insulation
What makes up 28% of what gets recycled?
Glass
What makes up 12% of what gets recycled?
Plastic
What makes up 39% of what gets recycled?
metals
The Global Recycling Network
an information exchange promoting recycling and ecofriendly products
What does recycling do?
saves energy and resources and decreases pollution
What will two-thirds of households participate in?
curbside recycling
What do successful recycling programs have?
- mandatory regulations, with warnings or sanctions for violators
- drop-off sites for large items
Newspapers
the most important item that is recycled
What percentage of newspapers are recycled?
78%
Recycled paper
routinely recovered andr erouted back into processing
Most MSW glass
containers for beverages
Bottle laws
require a deposit on all beverage containers
How many states have adopted bottle laws?
11
Numbers and letters on the bottom of plastic bottles
tell the type of plastic polymer in the bottle
Plastic bags
kill thousands of marine animals and turtles yearly and are hard to recycle and almost indestructible
Persistent organic pollutants (POPs)
DDT, toxaphene, chlordane, PCPs, dioxins
Toxicology
the study of the harmful effects of chemicals on human and environmental health
Where are POPs carried to in the air?
the Arctic
What happens after POPs condense on the snowpack?
they enter water during the spring thaw
Three-fourths of Inuit women
have PCB levels 5 times above safe levels
Effects of human exposure to chemicals
immune-system disorders, hormone disruptions, cancer, imbalances in births
Dose
level of exposure multiplied by the length of time of exposure
What is dose linked with?
response (effects)
What does exposure to hazardous chemicals come from?
the workplace, food, water, and environment
Threshold level
the level below which there are no ill effects
What do effects of the threshold depend on?
concentration and duration of exposure
Hazardous material (HAZMAT)
a chemical that presents a certain hazard or risk
Properties of hazardous materials
ignitability, corrosivity, reactivity, toxicity
Ignitability
substances that catch fire readily (gasoline)
Corrosivity
substances that corrode tanks and equipment (acids)
Reactivity
chemically unstable substances
chemically unstable substances
may explode or create toxic fumes if mixed with water (explosives, sulfuric acid)
Toxicity
substances that are injurious when eaten, inhaled, or touched (chlorine, pesticides, etc)
Two classes of toxic chemicals that do not readily break down
Heavy metals and synthetic organics
Heavy metals
are soluble in water and can interfere with enxyme functioning
Exposure of heavy metals
mental retardation, insanity, birth defects
Mining and industrial wastes; vehicle emissions; lead-acid batteries; fertilizers; paints; treated woods; plastics floating on the world’s oceans; and aging water supply
Common sources of heavy metals
Lead
the most prevalent heavy metal contaminant
Other examples of common sources
- mercury
- cadmium
- arsenic
Petroleum-derived and synthetic organics are the basis for…
plastics, fibers, synthetic rubber, paintlike coatings, solvents, pesticides, preservatives
Acute effects of being exposed to organic comounds
poisoning, death
extended exposure to organic compounds
mutagenic, carcinogenic, and teratogenic (causing birth defects) effects
Halogenated hydrocarbons
synthetic organics that contain halogens
Halogens
choline, brimine, flourine, iodine
Perchloroethylene (PERC)
a halogenated hydrocarbon
What here PERCs used in?
dry cleaning as a solvent, in home products
Phythalates
soften plastic and possible hormone disrupters
Bisphenol A (BPA)
used in plastics
Why are heavy metals and nonbiodegradable synthetic organics hazardous?
they bioaccumulate
Why did the minamata disease occur in Japan?
Mercury bioaccumulated and biomagnified
What ended disposal of hazardous wastes into the air and water?
the Clean Air and Clean Water Acts
Deep-well injection
boreholes are drilled thousands of feet below groundwater into porous formations
Wastes in wells
react with natural material, leaving them less hazardous
EPA’s Underground Injection Control Program
wells must be limited to geologically stable areas
Wells
can keep toxic wastes from contaminating water
Ponds
excavated depressions into which liquid wastes are drained and held
Impoundments can receive wastes indefinitely if:
the bottom is well sealed, and evaporation equals input of wastes
Secure landfill
a reasonably safe landfill that is lined, has a leachate-removal system, and is monitored and properly capped
What are concentrated liquids or solids put into?
drums
When ealry land disposal was not regulated…
deep wells injected wastes into groundwater
Midnight dumping
disreputable businesses pocketed fees, then illegally dumped wastes in abandoned warehouses, vacant lots, or landfills
Orphan sites
some companies or individuals stored wastes on their own property, then went out of business, abandoning the property and wastes
Love Canal, New York
brought the problem of unregulated dumping to the public’s attention
Problems of toxic chemical wastes occur in three areas:
- cleaning up messes already created
- regulating disposal of wastes being produced
- reducing the quantity of hazardous waste product
