-steady flow of varied wastes that we all produce.
- collecting and dumping processes make separation nearly impossible
-mixing of hazardous waste
what are open dumps?
open, unregulated dumps are still the predominant method of waste disposal in developing countries.
-most developed countries forbid open dumping.
: estimated 200 million liters of motor oil are poured into sewers or soak into the ground each year in the US.
industrialized nations have agreed to stop shipping hazardous and toxic waste to less developed countries, but it still continues.
-each days trash is covered with a layer of soil to isolate it from the rest of the environment**(20% space Used)
-spread trash in thin layers, compacting it, and covering days accumulation with 6inches of soil. Then cover top with 20 inches graded so water will drain off finished surface( prevents lactate)
what is lactate?
refers to the water that filters down through a landfill, acquiring( leaching out) dissolved chemical compounds and/or fine grained solid and microbial contaminants as it goes.
this is sorted to remove recyclable and uncurable materials.
-higher energy content than raw trash
-reduces disposal volume by 80-90%
-residual ash usually contains toxic material.
incinerator cost and safety
initial construction costs are usually between $100 and $300 million for a typical municipal facility.
-tipping fees( cost to dump 1ton) are often much higher than tipping fees at landfills.
-EPA has found alarmingly high levels of dioxins, furans, lead and cadmium in ash.
-one way to control this is to remove heavy metals( batteries) and plastics before burning.
shrinking the waste stream
1. disposal methods for municipal solid waste in several developed.
2. Remaining landfill capacity.
what are the benefits to recycling?
-saving money, raw materials, and landfill space.
-encourages individual responsibility
-reduces pressure on disposal systems
-reduces energy consumption and air pollution.
-is any discarded liquid or solid that contains substances known to be:
-fatal to humans or laboratory animals in low doses
-toxic, carcinogenic, mutagenic, or teratogenic to humans or other life-forms
-ignitable with a flash point less than 60 degrees C.
-explosive or highly reactive.
-Comprehensive Environmental Response, Compensation and Liability Act (CERCLA) 1980
-modified by Superfund Amendments and Reauthorization Act (SARA) 1984
- Toxic released inventory- requires 20,000 manufacturing facilities to report annually on releases of more than 300 toxic materials.
what is brownfields?
contaminated properties that have been abandoned or are not being used up to potential because of pollution concerns.
hazardous waste management options
: STORE PERMANENTLY
-Retrievable storage: in containers in salt mines or caverns.
-Secure landfills: modern, complex landfills with multiple liners and other impervious layers, covered by a cap. Lactate is processed and monitoring sees that no toxins escape.
what is a city?
: US census bureau considers any incorporated community a city, and any city with more than 2,500 residents as urban.
-Rural areas, most residents depend on natural resources for their livelihood.
-Urban areas, most people are not directly dependent on natural resources-based occupations.
CON. What is a City?
A village- a collection of rural households linked by culture, customs, family ties, and association with the land.
A city- has a large enough resource base to allow residents to specialize in arts, crafts, services, or professions other than resources-based occupations.
A megacity- is a urban area with more than 10 million inhabitants. The largest megacity has 30 million people.
vast majority of humanity has always lived in rural areas where they subsisted in natural resources.
-huge URBAN AGGLOMERATIONS (merges of multiple municipalities) appearing around world.
causes of urban growth:
-natural increase : fueled by improved food supplies, better sanitation and medical care.
-immigration: caused by push factors forcing people out of the country, and pull factors drawing them into cities.
Push Factors: overpopulation in Countryside, Economics, Racial or Religious Conflicts, Land Ownership by a wealthy elite, Changes in Agriculture
Pull Factors: Excitement and Vitality of Cities, Jobs,Housing, Entertainment, Social Mobility and Power, Specialization of Professions
urban challenges in developing world
-Uncontrollable Growth: Traffic and Congestion- the number of vehicles growing faster than the pace of road construction.
: average resident spends 44 days a year in traffic jams.
: 20% of all fuel consumed by vehicles standing still.
CONT. Urban Challenges in the Developing World
-Uncontrollable Growth: Air pollution- poorly maintained vehicles, smokestacks from factories, and wood or coal fires for cooking or heating work together to create poor air quality in supercities
-Sewer Systems and Water Pollution
: only 35% of urban residents in developing world have satisfactory sanitation.
:1/3 do not have safe drinking water
what are urban challenges in the developing world?
traffic and congestion, air pollution, and sewer systems and water pollution
current world problems
-Housing : at least 1billion people live in SLUMS( legal but inadequate multifamily tenements) of central cities and in SHANTYTOWNS( settlements created when people build their own shacks on the outskirts of cities).
-sometimes people simply occupy land that they neither own nor rent, creating SQUATTER TOWNS which can have thousands.
-Urban Sprawl : in most American metropolitan areas, the bulk of new housing is in large, tract developments that leapfrog beyond city edges in search of inexpensive land.
urban sprawl consumes land
- developers claim that growth benefits the suburbs, but the opposite is often true because the new sites must build roads, water, sewers, and schools.
- the US department of housing and urban development estimates that urban sprawl consumes 500,000 acres(200,000 ha) of farmland per year.
expanding suburbs cause long commutes
-because many Americans live far work, they consider a private automobile essential.
: Average US driver spends the equivalent of one 8hr day/ week behind the wheel.
: 1/3 of all land is devoted to automobile infrastructure.
social consequences of urban sprawl
with a reduced tax base and fewer civic leaders living or working in downtown areas, the city is unable to maintain its infrastructure.
-sprawl promotes a sedentary lifestyle.
what is Smart growth
- makes efficient and effective use of land resources and existing infrastructure.
-minimizes wasted space and money.
-makes land-use planning democratic.
-Mixes land uses.
-Preserves natural spaces.
CONT. SMART GROWTH
Portland, Oregon: enforced a boundary on outward expansion, forcing in- filling unused space.
- population grew 50%
- land grew 2%
- air pollution decreased by 86%
-Similar population growth, but extensive urban sprawl
-land area increased by 300%
-property taxes increased by 22%
-air pollution increased by 5%
open space design preserves landscapes
typically divides land into a checkerboard layout of 1-5 ha parcels with no designated open space.
: CONSERVATION DEVELOPMENT- (also called cluster development) preserves at least half of a subdivision as natural areas, farmland, or other forms of open space.
sustainable development- meeting the needs of the present without compromising the ability of future generations to meet their own needs.
-any form of wealth available for use on the production of more wealth.
-natural- from nature
-human Iraq cultural- knowledge, experience
-manufactured it built- tools, infrasture
-social- shared values, trust, cooperation
demand- is the amount of a product or service consumers are willing and able to buy at various prices assuming they are free to express their preferences.
supply- is the quantity of that product being offered for sale at various prices.
(REVIEW THE GRAPH THAT IS ON THE SLIDE)
classical economics CONT.
-supply and demand should come into MARKET EQUILIBRIUM at the point of intersection of the two curves.
-Marginal Cost: for the seller, the cost of producing one more unit of a product Iraq service.
-Marginal Benefit: for the buyer- how much would I benefit by buying one or more unit?