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Explore the impacts of waste generation, disposal methods, and the importance of the 3 R's in waste management - Reduce, Reuse, Recycle. Learn about the environmental benefits and challenges of recycling, composting, landfill usage, and incineration. Discover how recycling conserves resources and reduces pollution to build a sustainable future.
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Paper or Plastic? Polystyrene(styrofoam): does not break down in landfills, made from oil. Input/Output Analysis: Cradle to grave or life cycle analysis. Paper Cup: 2 grams of petroleum, 33 grams of wood, 2x as much energy and water(as styrofoam). Styrofoam: 3 grams of petroleum, no wood or bark.
General Material Flow in an Economy: Waste: outputs! Hard to determine what is useful or not.
The Throw-Away Society • After WWII and rapid population growth US pattern consumption changed. • Items were purchased and thrown away and repurchased. • Fewer things were recycled. • Varies for geographic area, season, year, income. • Municipal Solid Waste(MSW): refuse collected. • 60%: residences • 40%: commercial and institutional facilities.
Content of the Solid Waste Stream Waste Stream: the flow of solid waste that is recycled, incinerated, placed in a solid waste landfill or disposed of in another way.
E-Waste is Particularly Problematic! • 2% of waste stream, environmental effect is great.
Costs more to recycle than to dispose of E-Waste. • Most is exported to China and dismantled. • Contain toxic metals such as mercury, cadmium and lead
Solving the MSW Problem • The only TRUE solution to our MSW problem is the 3 R’s (in order of preference): • Reduce • Reuse • Recycle
(1) Reduce • Source reduction – MOST EFFECTIVE!!! • Design & manufacture products in ways that decrease the volume of solid waste created. • Technological development can constantly decrease the size and weight of a product. • Uses less energy. • Subaru: produced 200,000 cars in 2009 and sent no waste to landfills.
(2) Reuse • Allows a material to cycle within a system longer before becoming an output. • NO energy or resources are needed to be reused. • Extendsresource supplies and requires less energy than re-mining, re-manufacturing, etc • Ex: Refillable beverage containers • Ex: Reusable shipping containers and grocery bags
(3)Recycle • Materials destined to become MSW are collected and converted into raw materials then produce new objects.
(3) Recycle • Recycle these: • Glass bottles, newspapers, steel cans, plastic bottles, cardboard, office paper • Every ton of recycled paper saves: • 17 trees • 7000 gallons of water • 4100 kwatt-hrs of energy • 3 cubic yards of landfill space
Characteristics of Recyclable Materials • *Easily isolated from other waste • *Available in large quantities • *Valuable • *Pay-as-you-throw garbage collection
Reduces global warming Reduces acid deposition Reduces urban air pollution Make fuel supplies last longer Reduces air pollution Saves energy Reduces energy demand Reduces solid waste disposal Recycling Reduces mineral demand Reduces water pollution Reduces habitat destruction Protects species Benefits of Recycling
(3) Recycle – “Closed Loop” System = remade into same product • *40% of aluminum recycled in US • *Recycled aluminum uses 90% fewer resources than new aluminum
Recycling in the US • *Centralized recycling of mixed wastes • *Economic benefits! • *Recycling in the US is increasing!
USA still needs to improve: • Recycling Metals other than Aluminum • Lead, gold, iron, steel, silver and zinc • Recycling Plastic • Less than 20% is recycled • Less expensive to make plastic from raw materials than to recycle! • ☹
Composting • Organic matter that has decomposed under controlled conditions to produce an organic-rich material that enhances soil structure, cation exchange capacity and fertility. • Includes: • Food scraps • Sewage sludge • Agricultural manure • Yard waste • Reduces yard waste in landfills. • Can be sold or distributed to community.
Air and water must be supplied to facilitate natural aerobic decomposition. • N & C must be in the correct ratio as dictated by green and brown material. • Piles get hot which kills microbes.
Trash: Landfill or Incinerated • Created in the 1930s. • Leachate: water that leaches through the solid waste and removes various chemical compounds it comes into contact with.
Sanitary Landfills • Holds MSW. • Constructed with a clay or plastic lining at the bottom. • Clay impedes the flow of water and can retain positively charged ions such as metals. • Capped when capacity is reached. • Leachate is tested for toxicity. • Tipping Fee: charge per load dropped.
Choosing a Site For a Sanitary Landfill • Known as a siting. • Near an area rich in clay. • Away from bodies of water (rivers, lakes, streams). • Consider distance. • NIMBY: not in my backyard.
Problems Associated With Landfills • Leaking lechate. • Anaerobic decomposition: generates methane and carbon dioxide. • Methane gas can lead to explosions. • Need a specific mixture of air, moisture, and organic material to decompose to occur.
Incineration • Burning! • Produces ash. • Metals or other toxins may be released into the atmosphere or remain in the ash. • Waste-to-energy: heat generated by incineration is used rather than released into the atmosphere.
Problems with Incineration • Issues of where to “sit” them. • Releases air pollutants. • Produce ash that may be more concentrated with toxins. • Large and expensive to build. • Difficult to have a uniform burn.
Haz-Mats • Liquid, solid , gas or sludge waste material. • Harmful to humans/ecosystems. • 20,000 generators in US = 40 million ton/year • Only 5% recycled • Households generate 1.5 million ton/year
Haz-Mats • Any discarded chemical that threatens human health or the environment • Flammable, Reactive, corrosive, explosive or toxic chemicals • TOXIC: cancers, mutations, birth defects
Haz-Mat Sources • Cleaning machinery • Manufacturing computer parts • Dry cleaners • Auto service stations • Households: over cleaners • Fuels, solvents, lubricants, pesticides
Haz-Mat Legislation • Resource Conservation and Recovery Act (RCRA) • “Cradle to grave” documentation of Haz-Mat, protect human health, and to track the haz-mat materials. • Federal Hazardous and Solid Waste Amendment (HSWA) – encouraged waste minimization, phased out the disposal of hazardous wastes on land. Also increased law enforcement authority.
Haz-Mat Legislation • Comprehensive Environmental response, Compensation, and Liability Act (CERCLA) (Superfund Act) • Tax producers • Clean-up abandoned sites where unknown ownership • National Priorities List (NPL) • NJ: 114 sites alone, NY/PA 94 each
Superfund National Priorities List • 2006: 1558 sites on the list
Produce Less Waste Manipulate processes to eliminate or reduce production Recycle and reuse Convert to Less Hazardous or Nonhazardous Substances Chemical physical, and biological treatment Ocean and atmospheric assimilation Thermal treatment Land treatment Incineration Put in Perpetual Storage Aridregion unsaturated zone Underground injection Waste piles Surface impoundments Salt formations Landfill Dealing with Hazardous Wastes
Superfund example: Love Canal, NY • Hazardous Waste Landfill. Was covered with topsoil and used for a school and a housing development. • People had abnormally high incidents of cancer • 1970’s Lois Gibbs • 1983 Superfund Designation • 1994 taken off the NPL list
Brownfields • Contaminated Industrial commercial areas that are not Superfunds • Cleanup/remediation before they can be redeveloped • Old factories, industrial areas, gas stations, dry cleaners, landfills, rail yards
Brownfields • State/local cleanup • Do not hold the polluter responsible • Best solution: Bioremediation
Detoxifying Wastes • *Bioremediation • -Uses organisms to break down wastes • -Ex: Phytoremediation uses plants to remove wastes from soil • -Ex: Mycoremediation uses fungi
Hanford, Washington -2/3 of all US highly radioactive waste
Cleaning up existing hazardous waste: superfund program • Leaking chemical storage tanks and drums • Pesticides dumps • Piles of mining wastes • Must be cleaned up
Plastic cover Gas vent Earth Impervious clay cap Sand Topsoil Clay cap Leak detection system Bulk waste Reaction wastes in dreams Impervious clay Earth Groundwater monitoring well Water table Groundwater Double leachate collection system Plastic double liner Hazardous Waste Landfill Fig. 21.16, p. 539
Waste transporter Elevator shaft Hazardous waste Support column Inspector Above Ground Hazardous Waste Disposal Fig. 21.17, p. 540
Advantages Disadvantages Safe method if sites are chosen carefully Wastes can be retrieved if problems develop Low cost Leaks or spills at surface Leaks from corrosion of well casing Existing fractures or earth quakes can allow wastes to escape into groundwater Encourages waste production Deep-well Disposal