APES Unit 9 (ch 20, 21, 22)
government urged to do 2 major things by proponents of higher gasoline taxes
- fund programs to educate people about the hidden costs they are paying for gasoline - use gasoline tax to revenues to help finance mass-transit systems, bike lanes, and sidewalks as alternative to cars, and reduce taxes on income, wages, and wealth to offset the increased taxes on gas
Basel Convention
1992; international treaty that bans countries from shipping hazardous waste (ex. e waste) to or through other countries without their permission; 1955- outlawed all all transfers of hazardous waste from industrial countries to less-developed counties, ratified by 179 countries
north pacific garbage patch
2 gigantic masses of small pieces of plastic/ other solid wastes (harmful to marine animals) in the middle of the North Pacific Ocean near Hawaiian Islands, trapped by vortex where rotating ocean currents (gyres) meet; about 80% comes from land, rest dumped by ships
mining's effect on water pollution
3rd biggest source of water pollution; creates erosion of sediments and runoff of toxic chemicals into surface waters
surface impoundment advantages/disadvantages
A: low cost, wastes can often be retrieved, can store wastes indefinitely with secure double liners D: water pollution from leaking liners/ overflows, air pollution from volatile organic compounds, output approach encourages waste production
rapid rail advantages & disadvantages
A: much more energy efficient per rider & produces less air pollution than cars/planes, can reduce need for air travel, cars, roads, parking areas D: costly to run/maintain, causes noise/vibration to those nearby, asks some risk of collision at car crossings
plasma arc advantages/disadvantages
A: produces mixture of CO&H2 that can be used as fuel, easy to move to different sites, produce no toxic ash D: high cost, produces CO2&CO, can release particulates and chlorine gas, can vaporize & release toxic metals/ radioactive elements
bicycles- advantages & disadvantages
A: quiet/nonpolluting, take few resources to manufacture, burn no fossil fuels, require little parking space D: no protection in accidents, no coverage from weather, impractical for long trips, bike lanes/ secure bike storage not widespread
buses advantages & disadvantages
A: reduce car use and air pollution, can be rerouted if needed, cheaper than heavy-rail system D: can lose $ b/c they require affordable fares, can get caught in traffic and add to noise/ pollution, commit riders to transportation schedules
deep-well disposal advantages/disadvantages
A: safe if sites are chosen carefully, wastes can often be retrieved, low cost D: leaks can occur from corrosion of well casing, emits CO2/ air pollutants, output approach that encourages waste production
mass transit rail advantages & disadvantages
A: uses less energy/ produces less air pollution than cars do, uses less land than roads/parking lots, causes fewer injuries and deaths than cards D: expensive to build/ maintain, cost-effective only in densely populated areas, commits riders to transportation schedules
CERCLA/ Superfund program
Comprehensive Environmental Response, Compensation, and Liability Act, 1980 goals are to identify sites (Superfund sites) where hazardous wastes have contaminated the environment and to clean them up on a priority basis-- good idea but because it is not funded by many, it can't really do much
secondary sewage treatment
biological process in which aerobic bacteria removes as much as 90% of dissolved and biodegradable, oxygen0demanding wastes
hazardous wastes: organic compounds, toxic heavy metals, radioactive
OC- solvents, pesticides, PCBs, dioxins THM- nondegradable; lead, mercury, arsenic Radio- produced by nuclear power plants/ nuclear weapons facilities *US is the largest producer
User-pays approach
Reducing harmful effects of automobiles by making drivers pay directly for most of the environmental & health costs caused by their automobile use- kind of like full-cost pricing
Fundamental land
Requires approval from local and provincial governments and from state council to build on this land
RCRA
Resource Conservation and Recovery Act, 1976 set standards for for the management of several types of hazardous waste and issue permits to companies that allow them to produce and dispose of a certain amount of those wastes by approved methods
sanitary landfill advantage/ disadvantage
advantage: low cost, can handle large amounts of waste, filled land can be used for other purposes, no shortage of landfill space in many areas disadvantage: noise, traffic, dust, releases greenhouse gases unless collected, encourages waste production, eventually leaks and contaminates groundwater
reduce surface pollution from non point source
agriculture: reduce erosion, reduce amount of fertilizers, plant buffer zones of vegetation, use organic farming techniques, use pesticides prudently, tougher pollution regulations for livestock operations
main causes of water pollution
accidental/ deliberate dumping of chemicals, malfunctioning sewage treatment plans, non point runoff of pesticides & excess plant nutrients from cropland & animal feedlots
motor vehicles
accidents kill about 1.3mill people/year and injure 50million people, kill 50million wild animals/family pets every year. largest source of outdoor air pollution, causes 30,000-60,000 premature deaths/year; fastest-growing source of climate-changing CO2 emissions
prevent/ reduce cultural eutrophication
advanced waste treatment processes to remove nitrates & phosphates from waste water before it enters body of water, banning/limiting use of phosphates in household cleaning agents, soil conservation/ controls to reduce soil erosion *more effective and cheaper than cleanup
case study: bottled water
americans are world's largest consumers of bottled water; less regulated than tap water, EPA contamination standards that apply to public water supplies don't apply to bottled water; 67 million bottles discarded every day, most end up in landfills or scattered on land
hazardous/ toxic waste
any discarded material or substance that threatens human health or the environment because it's poisonous, dangerously chemically reactive, corrosive, or flammable (car batteries, household pesticides, industrial solvents, etc)-- can lead to pollution of air/water, natural capital degradation, health threats
solid waste
any unwanted or discarded material we produce that is not liquid or gas
noise pollution
any unwanted, disturbing, or harmful sound that damages, impairs, or interferes with hearing, causes stress, hampers concentration and work efficiency, or causes accidents.
light pollution in cities
artificial light created by the buildings can disrupt plants and animal species, makes it difficult for astronomers to observe night sky
reduce hazardous waste
avoid using pesticides/ hazardous chemicals; use less harmful substances instead of commercial household cleaners; do not dump hazardous chemicals down toilet, storm drain, etc; don't throw old fluorescent light bulbs into regular trash since they contain mercury
case study: urbanization in the US
between 1800-2012, % of US population living in urban areas rose from 5% to 82%- 3 phases of the population shift: people migrated from rural areas to large central cities; many people migrated from large central cities to smaller cities and suburbs; many people migrated form the North and East to the South and West. since 1920, many of worst urban environmental problems in the US have been reduced significantly (better working/housing conditions, better sanitation, etc). concentration of most of population in urban areas has helped protect country's biodiversity. central cities (especially older ones) have deteriorating services & aging infrastructures (streets, bridges, etc)
bioplastics
biodegradable and more environmentally sustainable plastics; can be made from corn, soy, sugarcane, switchgrass, chicken feathers, and some components of garbage
detoxify hazardous wastes- biological methods
bioremediation- bacteria & enzymes help to destroy toxic or hazardous substances, or convert them to harmless compounds. takes longer to work but costs much less phytoremediation- natural/ genetically engineered plants to absorb, filter, and remove contaminants from polluted soil and water, can help clean up toxic hotspots
secure hazardous waste landfills
both liquid and solid hazardous wastes put into containers and buried, carefully designed and monitored
Persisten Organic Pollutants (POPs)
can accumulate in fatty tissues of humans/ animals that have high tropic levels in food webs (bio-accumulation); persist in the environment and can be transported long distances by wind and water
recycling disadvantages
can cost more than burying in area w/ landfill space, reduces profits for landfill/ incinerator owners, inconvenient for some, costly and can add to taxpayer burden
natural recovery of rivers
can recover from levels of degradable, oxygen-demanding wastes through processes of dilution and bacterial biodegradation; does not work when flooded, overloaded, drought, or damming does not eliminate slowly degradable and not degradable pollutants
plastic bags
can take 400-1,000 years to break down, less than 1% out of 102 billion used each year are recycled, block drains/ sewage systems, can kill wildlife that try to eat them/ get stuck in them; taxes beginning to be put on shopping bags to encourage using reusable bags
water pollution
change in water quality that can harm living organisms or make the water unfit for human use (irrigation, consumption, etc)
strategies to reduce resource use, waste, pollution
change industrial processes to eliminate/ reduce harmful chemicals (helps company save money too); redesign manufacturing processes/ products to use less material/ energy; develop products that are easier to repair, reuse, remanufacture, compost, or recycle; eliminate or reduce unnecessary packaging; use fee-per-bag waste collection systems (charge consumers for amount of waste they throw away); establish cradle-to-grave responsibility laws (require companies to take back consumer products)
detoxify hazardous wastes- physical methods
charcoal/ resins to filter out harmful solids, distilling liquid wastes to separate harmful chemicals, precipitating (allowing natural processes to separate) chemicals from solution
3 steps to recycling
collecting materials, converting them to new materials, and the selling/buying of products containing recycled material *recycling does't work unless these steps are taken consistently
strengthen Drinking Water Act
combine smaller drinking water treatment systems w/ larger ones to make it easier for the small ones to meet federal standards, strengthen/enforce requirements concerning public notification of violations of drinking water standards, ban use of any toxic lead in new plumbing pipes/faucets/fixtures
urbanization advantages
concentrating ppl in cities preserves biodiversity by reducing stress on habitats; multistory buildings require less energy person to heat/cool than single-family homes; dwellers tend to drive less/ rely more on mass transport
oil in the ocean
contains volatile organic hydrocarbons that kill many aquatic organisms immediately upon contact; coat feathers of seabirds and destroys their natural buoyancy and heat insulation; smother bottom-dwelling organisms, can kill coral reefs
leachate
contaminated water from landfills
case study: arsenic in drinking water
contaminates drinking water when well is drilled into aquifer where the soil and rock are naturally rich in arsenic or when mining/ ore processing release arsenic WHO estimates 140million+ ppl drinking water w/ arsenic contents-- long-term exposure likely to cause premature deaths from cancer of skin, bladder, & lungs
detoxify hazardous wastes- chemicals methods
convert to harmless or less harmful chemicals; cyclodextin (sponge-like sugar made from cornstarch) to remove toxic chemicals from contaminated soil/groundwater. nanomagnets- magnetic nanoparticles coated w/ certain compounds that can remove pollutants from water and can then be separated out and disposed/ recycled
RRRR
could eliminate up to 80% of solid waste we produce by applying these strategies: Refuse*, Reduce*, Reuse*, Recycle-- save matter and energy resources, pollution, help protect biodiversity, save money *input, or waste prevention, approaches the problem before it occurs
urbanization
creation and growth of urban and suburban areas; about 52% of world's people live in urban areas
crude petroleum vs refined petroleum
crude- oil as it comes out of the ground refined- fuel oil, diesel, gasoline, processed petroleum products *both highly disruptive pollutants
importance of RRRR
decrease our consumption of matter and energy resources, reduce pollution and natural capital degradation, save money
zoning
designating specific ares of land for particular types of use
disinfection
disinfect treated water before it enters tertiary treatment or sent out to environment- usually by UV, chlorination or bleaching
cities lack vegetation
don't have many plants/trees to absorb air pollution, give off oxygen, dampen urban noise
key principles to prevent pollution, reduce waste, transition to low-waste society
everything is connected; there is no "away" for the wastes we produce then "throw away"; producers/ polluters should pay for the wastes they produce; can mimic nature by reusing, recycling, composting, or exchanging most of the municipal solid wastes we produce
dispersed cities
expand and spread outward, depend on motor vehicles for most travel (US, Canada, Australia) *US has 4.4% of world's people but has about 25% of world's 1billion+ motor vehicles- use 43% of world's gasoline
waste-to-energy incinerator disadvantages
expensive to build, produces a hazardous waste, emits some CO2/ air pollutants, encourages waste production
contaminated drinking water
exposure to infectious disease (typhoid fever, cholera, etc) by bacteria, viruses, and parasites *1.6 million people die each year from preventable waterborne diseases that they get by drinking contaminated water
postconsumer waste
external waste generated by product use
case study: e waste
fastest-growing solid waste problem in world- only about 14% is recycled, rest ends up in landfills/ incinerators, even though they contain valuable materials that could be reused/recycled; most of it is shipped to developing countries where workers try to recover the valuable metals/ reusable parts but exposed to toxic metals/ harmful chemicals
open dump
field or large pit where garbage is deposited and sometimes burned; widely used in cities of less-developed countries
waste management
finding ways to reduce impact that the waste has on the environment but not reducing the amount it is produced; usually involving mixing wastes together and then transferring them from one part of the environment to another, by burying them, burning them, or shipping to another location
ecoindustrial revolution
focused development of a global network of industrial ecosystems over the next few decades
municipal solid waste (MSW)
garbage/ trash, consists of combined solid waste produced by homeland workplaces other than factories (ex. cardboard, food waste, cans)- mostly buried in landfills or burned in incinerators in developed countries (US is largest producer of this)
encourage reuse/recycling
gov can increase subsidies and tax breaks for reusing/recycling materials, and decrease subsidies and tax breaks for making items from virgin resources
environmental justice movement
growing grassroots (bottom-up) approach to environmental discrimination throughout the world
compact cities
grows upward and downward, occupies a small land area with a high population density (hong kong, china, tokyo, japan). get around by walking, biking, or mass transit
urban sprawl
growth of low-density development on edges of cities and towns, result of affordable land, automobiles, funding of highways, inadequate urban planning; eliminating surrounding agricultural and wild lands & emit greenhouse gases/ air pollution
source separation
households/ businesses separating their trash into recyclable categories (glass, paper, metal, etc)-- produces less air/ water pollution, costs less to implement that do MRFs
cultural eutrophication
human activities that greatly accelerate the input of plant nutrients to a lake, can produce dense growths or "blooms" -- primary cause of dead zones *85% of large lakes near major US population contain some degree of this
environmental justice
ideal where everyone is entitled to protection for environmental hazards regardless of race, gender, age, national origin, income, social class, or any political factor *polluting factories, waste dumps, etc are located in communities mostly populated by african american, asian americans, latinos & native americans and toxic waste sites have been cleaned up faster in white communities
incinerators
if poorly designed and burned all at once, can cause pollution and compete w/ many low-cost landfills; doesn't really encourage the increase of reuse and recycling in denmark, they use filters to remove pollutants and run so cleanly that they release just a fraction of the toxins released by typical fireplaces and bbqs
plastic's effect on water pollution
improperly discarded can cause it to end up in waterways which in turn harm wildlife
coastal water pollution cleanup
improve oil-spill cleanup capabilities, use nano particles on sewage and oil spills to dissolve them
Toxic Substances Control Act 1976
intended to regulate/ ensure safety of chemicals- companies must notify EPA of their chemical before introducing it to the marketplace, but don't have to give any data of its safety. any chemical is viewed as safe unless the EPA (w/ a very low budget) can show that it is harmful
preconsumer waste
internal waste generated in manufacturing process
6 factors that promote urban sprawl
jobs, housing, food, health care, educational opportunities, entertainment
agricultural activities' effect on water pollution
leading cause of H2O pollution: eroded sediment is most common pollutant; fertilizers & pesticides, bacteria from livestock/ food-processing wastes, excess salts from from soils of irrigated land
surface impoundments
lined ponds, pits, or lagoons in which liquid hazardous wastes are stored; when the water evaporates and the waste becomes more concentrated, it can filter into the groundwater if no liner is used to contain the waste and threaten water supplies. if not covered, harmful chemicals can evaporate into the air
deep-well disposal
liquid hazardous wastes are pumped under pressure through a pipe into dry, porous rock formations underneath aquifers; sometimes wastes leak into groundwater, output approach encourages production of hazardous wastes-- in US, almost 2/3 (will increase sharply) of liquid hazardous wastes are injected into deep disposal wells that are viewed as inadequate
dirty dozen
list of 12 hazardous chemicals, includes DDT and 8 other chlorine-containing persistent pesticides, PCBs, dioxins, and furans-- likely that nearly every person on earth has detectable levels of POPs in their bodies
urban sprawl natural capital degradation
loss of cropland; loss/fragmentation of forests, grasslands, wetlands, wildlife habitat; increased pollution of surface/groundwater; increased runoff and flooding; increased energy use and waste; increased emissions of air pollutants; more unemployment in central cities
materials-recovery facilities (MRF)
machines or workers separate mixed household/ business waste to recover valuable materials for sale to manufacturers as raw materials; remaining paper, plastics, etc are recycled or burned to produce steam or electricity which is used to run the plant/ sold to nearby industries-- encourages people to produce more trash
recycling paper
making recycled paper uses 64% less energy & produces 3% less water pollution and 74% less air pollution than making paper from wold pulp *production of paper is world's 5th largest consumer of energy
factors that inhibit reuse/recycling
market prices of most products are not full-priced; uneven economic field: resource-extracting industries receive more gov tax breaks/ subsidies than reuse/ recycling industries get; demand & price for recycled material fluctuates because buying goods with recycled materials is not a priority
how to test water pollutants
measure amount in a cup, level of dissolved oxygen (excessive amount of oxygen-demanding wastes can deplete DO levels in water), chemical analysis (determine presence/ concentration of specific organic chemicals in water)
clean up cultural eutrophication
mechanically removing excess weeds, controlling undesirable plant growth w/ herbicides & algaecides, pumping air into lakes/ reservoirs to prevent oxygen depletion-- all expensive/ energy-intensive
case study: recycling e-waste
more than 70% of world's e-waste is shipped to china where people work to extract valuable metals from discarded electronics at very low wages in dangerous conditions; atmospheric levels are 86 times higher than world health organization safety standards, 82% of children younger than 6 suffer from lead poisoning. US produces 50% of world's e-waste but only recycles 14% of it; only real long-term solution is a prevention approach through which electronic products are designed w/o use of toxic materials and can be easily repaired, remanufactured, recycled
cadmium
natural element in earth's crust- long-term exposure to even small amounts causes threats to health, carcinogen, kidney failure/problems, bone softening
how urban areas grow
natural increase- more births than deaths immigration (mostly from rural areas)
eutrophication
natural nutrient enrichment of a body of water, caused mostly by runoff of plant nutrients and phosphates from the land bordering them
lakes/ reservoirs' ability to dilute pollutants
not as effective as streams because they contain stratified layers that don't mix very much and have low or no flow rates-- flushing and changing of water can take 1-100 years instead of several weeks for streams *makes them more vulnerable to contamination by runoff/ discharge
oligotrophic vs eutrophic
o- low in nutrients and clear e- more nutrients, foggier
urban areas' ecological footprints
occupy only about 3% of earth's land area but consume about 75% of its resources and produce 75% of world's pollutions and wastes-- huge ecological footprints
case study: solid waste in US
only 4.6% of world's people but produces 25% of solid waste, about 98.5% of all solid waste produced is industrial solid waste, 1.5% is MSW
recycling plastic
only about 7% of plastic wastes in US is being recycled b/c there are many different types of plastics which are difficult to separate from products that contain them
eco-village movement
people come together to to design and live in more sustainable villages in rural/suburban areas and in neighborhoods or "eco-hoods" within cities
primary sewage treatment
physical process that uses screen/ grit tank to remove large floating objects and to allow solids (sand, rock) to settle out; then waste stream flows into primary settling tank where suspended solids settle as sludge *remove about 60% of suspended solids & 30-40% of oxygen-demanding wastes from sewage
land-use planning
planning to determine the best present and future uses of land
hydraulic fracturing/ fracking
potential threat to groundwater by causing leaky well pipes and from contaminated wastewater brought to the surface during tracking operations- removal of contaminant is very difficult & costly
5 undesirable effects of urban sprawl
poverty, lack of land for growing food, famine, war, religious/racial/political conflicts
water pollution solutions
prevent groundwater contamination, reduce non point runoff, work with nature to treat sewage & reuse treated wastewater, find substitutes for toxic pollutants, RRRR, reduce air pollution, reduce poverty, slow population growth
final settling tank (secondary clarifer)
primary sewage treatment, remove microorganisms that settled to bottom of the tank and send back to aeration
settling tank (primary clarifer)
primary sewage treatment, remove solids that are more organic in nature but take longer to settle
bar screening
primary sewage treatment, removes physical objects such as wood
grit chamber
primary sewage treatment, uses screens to remove non biological physical objects such as gravel
dealing with hazardous waste
produce less, convert as much as possible to less-hazardous substances, and put rest in long-term safe storage-- most countries do not follow these priorities
pollution in cities
produce most of world's air/water pollution and solid/hazardous waste; pollutant levels generally higher bc pollution produced in a smaller area can't be dispersed/ diluted as easily. motor vehicle pollution and nitrogen nutrients in runoff disrupt carbon and nitrogen cycle.
waster reduction
produce much less waste and pollution, and the wastes we do produce are considered to be potential resources that we can reuse, recycle, or compost`
industrial solid waste
produced by mines, farms, and industries that supply people with goods and services
cleanup groundwater pollution
pump to surface, clean, return to aquifer (expensive); inject microorganism to clean up contamination (still costly); pump nano particles of inorganic compounds to remove pollutants
urban growth
rate of increase of urban populations
primary/ closed loop recycling
recycled into new products of the same type
upcycling
recycling materials into products of higher value
biomimicry
redesigning industrial manufacturing to mimic how nature deals with wastes to be cleaner and more sustainable-- provide many economic benefits for businesses and encourages them to come up with new, environmentally beneficial processes/ products
recycling advantages
reduces energy/ mineral use and air/ water pollution; reduces greenhouse gas emissions; reduces solid waste *estimated that in 2010, recycling/composting in US reduced emissions of CO2 by an amount about equal to that emitted by 36 million passenger vehicles
waste-to-energy incinerator advantages
reduces trash volume, produces energy, concentrates hazardous substances into ash for burial, sale of energy reduces cost
stockholm convention on POPs (2000)
regulates use of 12 widely used Persistent Organic Pollutants
US Safe Drinking Water Act of 1974
requires EPA to establish national drinking water standards- maximum contaminant levels- for any pollutants that could have negative effects on human health
purify drinking water
reservoirs and purification plants, convert sewer water into drinking water, intense sunlight (UV rays) to kill infectious microbes,
industrial facilities' effect on water pollution
second major source of water pollution; emit variety of harmful inorganic & organic chemicals
aeration tank
secondary sewage treatment, removes dissolved pollutants from wastewater using microorganisms
coastal water pollution prevention
separate sewage/ storm water lines, require secondary treatment of coastal sewage, use wetlands/ natural methods to treat sewage, ban dumping wastes & sewage by ships, regulate coastal development/oil drilling/ oil shipping, require double hulls for oil tankers
clean water act of 1972
sets standards for allowed levels of 100 key water pollutants and requires polluters to get permits that limit the amounts they can be discharged at improvements in US water quality: 95% of all americans are served by public drinking water that meet federal health standards, 60% of all tested US streams, lakes, estuaries can be used for recreation (compared to 30% in '72), 75% of US is served by sewage treatment plants, annual losses of US wetlands have been reduced by 80% since '92
burial of hazardous waste
should use only as last resort after first priorities have been exhausted but right now it is the most widely used method in US and most countries, mostly because it is the least expensive of all methods
case study: portland, oregon
since 1970s has used smart growth strategies & strong land policies to control sprawl, reduce dependence on automobiles, & provide green space- one o frost sustainable US cities. encourages clustered, mixed-use neighborhood to allow people to meet most of their daily needs w/o a car- has saved its residents more than $1billion/year in transportation costs & positively contribute to public health. implemented recycling system in '87, one of highest recycling rates in country and reduced greenhouse gas emissions to 26% below 1990 levels. *important b/c big cities have huge environmental impacts and it is better for them to have sustainable life styles
Ohio's Cuyahoga River
so polluted that it caught fire several times- prompted officials to enact laws to limit discharge of industrial wastes into river/ local sewage systems; now it is much cleaner
sanitary landfill
solid wastes spread out in thin layers, compacted, and covered daily with a fresh layer of clay or plastic foam-- helps keeps it dry and reduce leakage of contaminated water, lessens risk of fire, decreases odor, reduces accessibility to vermin
prevent groundwater pollution
substitutes for toxic chemicals, keep toxic chemicals out of the environment, require leak detectors on underground tanks, ban hazardous waste disposal in landfills/ injection wells, store harmful liquids in aboveground tanks w/ leak detection & collection systems
resulting organic matter from composting
supply plant nutrients, slow erosion, improve crop yields, retain water
detoxify hazardous wastes- plasma gasification method
technology that uses arcs of electrical energy to produce high temperatures in order to vaporize trash in the absence of oxygen- reduces volume by 99%, produces synthetic gaseous fuel, & encloses toxic metals in glassy lumps of rick-- high cost
cities' affect on local climates
tend to be warmer, foggier, rainier, and cloudier--enormous amounts of heat generated by cars, factories, furnaces, lights, air conditioners, and heat-absorbing dark roods and street creates urban heat island (increases dependence on air conditioning- high energy consumption) that is surrounded by cooler suburban and rural areas--can accelerate formation of photochemical smog. cities growing and merging heat islands makes it harder for the natural dilution and cleansing of polluted air to take place
3 major trends in urban population dynamics
the % of the global population living in urban areas has increased sharply, and this trend is projected to continue; the numbers and sizes of urban areas are mushrooming; poverty is becoming increasingly urbanized, mostly in less-developed countries
septic tank
underground tank for treating wastewater from home in rural/ suburban areas- sewage/wastewater is pumped into settling tank, grease and oil rise to the top and solids fall to the bottom and are decomposed by bacteria; resulting partially treated wastewater is discharged in a large drainage field through small holes in perforated pipes embedded in gravel/ crushed stone below soil's surface- soil filters out some potential pollutants and soil bacteria decompose biodegradable material
waste-to-energy incinerator
use heat they generate to boil water or make steam for heating water or interior spaces, or for producing electricity ; intended to burn trash that can't be recycled/ reused
reduce water pollution
use manure/ compost to fertilize yards, minimize use of pesticides, prevent yard wastes from entering storm drains, don't use water fresheners in toilets, don't flush medicines down toilet, don't pour harmful chemicals down drain
ways to reuse
use reusable lunch bag, only buy things in glass containers, store food in reusable containers, buy used furniture/clothes/etc, use cloth bags while shopping
tertiary sewage treatment
uses chemical and physical processes to remove specific pollutants left in water after primary/ secondary treatment
discharge trading policy
uses market forces to reduce water pollution; permit holder can pollute at higher levels than allowed in its permit by buying credits from permit holders who are polluting below their levels (like cap and trade)-- pollutants could build up to dangerous levels where credits are bought
integrated waste management
variety of ways for both waste disposal and waste reduction
case study: pollution in great lakes
vulnerable to pollution b/c water entering can take as long as 100 years to be flushed out; 1972 Great Lakes Water Quality Agreement to maintain/restore lakes' ecosystems; non point source pollution is greatest threat
pay-as-you-throw/ fee-per-bag
waste collection system that charges households on the amount of garbage that is picked up, but don't charge for picking up materials separated for recycling/ reuse
secondary recycling
waste materials converted into different products
resource exchange webs
wastes of one manufacturer become the raw materials for another- similar to food webs in natural ecosystems
cities have water problems
water demands increase= expensive reservoirs/canals must be built, which can deprive rural/ wild areas of surface water and deplete groundwater supplies. more prone to flooding and slick concrete ground causes water to rush into storm drains and flood that too, degrade wetlands which act as a natural sponge to absorb excess storm water. climate change: water shortage for those that depend on glaciers and flooding for coastal cities
case study: Gulf of Mexico's annual dead zone
water draining into Mississippi River from factories, cities, etc that eventually lead into Gulf of Mexico contain sediments, pollutants and fertilizers. the fertilizers cause explosions in phytoplankton population which eventually die. as they die, oxygen-consuming bacteria work to decompose the new large amount of algae. as a result, the level of oxygen is low (called hypoxia) and causes a dead zone, bc the area contains very little marine life ; drives away faster-swimming organisms and suffocates the bottom-dwelling ones-- lasts until fall when storms churn water and distribute dissolved oxygen *represents disruption in nitrogen cycle caused by humans
groundwater pollution
when pollutants (fertilizers, pesticides, gasoline) seep into groundwater from sources such as people spilling solvents (paint thinners, gasoline, oil) onto the ground