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Chapter 22 Solid and Hazardous Waste. Chapter Overview Questions What is solid waste and how much do we produce? What is solid waste and how much do we.

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Presentation on theme: "Chapter 22 Solid and Hazardous Waste. Chapter Overview Questions What is solid waste and how much do we produce? What is solid waste and how much do we."— Presentation transcript:

1 Chapter 22 Solid and Hazardous Waste

2 Chapter Overview Questions What is solid waste and how much do we produce? What is solid waste and how much do we produce? How can we produce less solid waste? How can we produce less solid waste? What are the advantages and disadvantages of reusing recycled materials? What are the advantages and disadvantages of reusing recycled materials? What are the advantages and disadvantages of burning or burying solid waste? What are the advantages and disadvantages of burning or burying solid waste? What is hazardous waste and how can we deal with it? What is hazardous waste and how can we deal with it?

3 Chapter Overview Questions (contd) What can we do to reduce exposure to lead and mercury? What can we do to reduce exposure to lead and mercury? How can we make the transition to a more sustainable low-waste society? How can we make the transition to a more sustainable low-waste society?

4 Core Case Study: Love Canal There Is No Away Between , Hooker Chemical sealed multiple chemical wastes into steel drums and dumped them into an old canal excavation (Love Canal). Between , 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. 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. The company inserted a disclaimer denying liability for the wastes.

5 Core Case Study: Love Canal There Is No Away In 1957, Hooker Chemical warned the school not to disturb the site because of the toxic waste. 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 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. In 1976, residents complained of chemical smells and chemical burns from the site.

6 Core Case Study: Love Canal There Is No Away President Jimmy Carter declared Love Canal a federal disaster area. President Jimmy Carter declared Love Canal a federal disaster area. The area was abandoned in 1980 (left). The area was abandoned in 1980 (left). Figure 22-1

7 Core Case Study: Love Canal There Is No Away It still is a controversy as to how much the chemicals at Love Canal injured or caused disease to the residents. 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. Love Canal sparked creation of the Superfund law, which forced polluters to pay for cleaning up abandoned toxic waste dumps.

8 WASTING RESOURCES Solid waste: any unwanted or discarded material we produce that is not a liquid or gas. Solid waste: any unwanted or discarded material we produce that is not a liquid or gas. Municipal solid waste (MSW): produce directly from homes. Municipal solid waste (MSW): produce directly from homes. Industrial solid waste: produced indirectly by industries that supply people with goods and services. Industrial solid waste: produced indirectly by industries that supply people with goods and services. Hazardous (toxic) waste: threatens human health or the environment because it is toxic, chemically active, corrosive or flammable. Hazardous (toxic) waste: threatens human health or the environment because it is toxic, chemically active, corrosive or flammable.

9 WASTING RESOURCES Solid wastes polluting a river in Jakarta, Indonesia. The man in the boat is looking for items to salvage or sell. Solid wastes polluting a river in Jakarta, Indonesia. The man in the boat is looking for items to salvage or sell. Figure 22-3

10 WASTING RESOURCES The United States produces about a third of the worlds solid waste and buries more than half of it in landfills. The United States produces about a third of the worlds solid waste and buries more than half of it in landfills. About 98.5% is industrial solid waste. About 98.5% is industrial solid waste. The remaining 1.5% is MSW. The remaining 1.5% is MSW. About 55% of U.S. MSW is dumped into landfills, 30% is recycled or composted, and 15% is burned in incinerators.About 55% of U.S. MSW is dumped into landfills, 30% is recycled or composted, and 15% is burned in incinerators.

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12 Electronic Waste: A Growing Problem E-waste consists of toxic and hazardous waste such as PVC, lead, mercury, and cadmium. E-waste consists of toxic and hazardous waste such as PVC, lead, mercury, and cadmium. The U.S. produces almost half of the world's e-waste but only recycles about 10% of it. The U.S. produces almost half of the world's e-waste but only recycles about 10% of it. Figure 22-4

13 INTEGRATED WASTE MANAGEMENT We can manage the solid wastes we produce and reduce or prevent their production. We can manage the solid wastes we produce and reduce or prevent their production. Figure 22-5

14 Fig. 22-5, p. 523 Primary Pollution and Waste Prevention First Priority Second PriorityLast Priority Release waste into environment for dispersal or dilution Bury waste in landfills Waste Management Incinerate waste Buy reusable recyclable products Recycle Repair products Make products that last longer and are recyclable, reusable, or easy to repair Reduce packaging and materials in products Use less of a harmful product Secondary Pollution and Waste Prevention Treat waste to reduce toxicity Purchase different products Reuse products Change industrial process to eliminate use of harmful chemicals Compost

15 Solutions: Reducing Solid Waste Refuse: to buy items that we really dont need. Refuse: to buy items that we really dont need. Reduce: consume less and live a simpler and less stressful life by practicing simplicity. 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. Reuse: rely more on items that can be used over and over. Repurpose: use something for another purpose instead of throwing it away. Repurpose: use something for another purpose instead of throwing it away. Recycle: paper, glass, cans, plastics…and buy items made from recycled materials. Recycle: paper, glass, cans, plastics…and buy items made from recycled materials.

16 Fig. 22-6, p. 524 Follow the five Rs of resource use: Refuse, Reduce, Reuse, Repurpose, and Recycle. Buy products in concentrated form whenever possible. Read newspapers and magazines online. Use in place of conventional paper mail. Refill and reuse a bottled water container with tap water. Do not use throwaway paper and plastic plates, cups and eating utensils, and other disposable items when reusable or refillable versions are available. Buy things that are reusable, recyclable, or compostable, and be sure to reuse, recycle, and compost them. Rent, borrow, or barter goods and services when you can. Ask yourself whether you really need a particular item. What Can You Do? Solid Waste

17 REUSE Reusing products is an important way to reduce resource use, waste, and pollution in developed countries. 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. Reusing can be hazardous in developing countries for poor who scavenge in open dumps. They can be exposed to toxins or infectious diseases. They can be exposed to toxins or infectious diseases.

18 How People Reuse Materials Children looking for materials to sell in an open dump near Manila in the Philippines. Children looking for materials to sell in an open dump near Manila in the Philippines. Figure 22-2

19 Case Study: Using Refillable Containers Refilling and reusing containers uses fewer resources and less energy, produces less waste, saves money, and creates jobs. Refilling and reusing containers uses fewer resources and less energy, produces less waste, saves money, and creates jobs. In Denmark and Canadas Price Edwards Island there is a ban on all beverage containers that cannot be reused. In Denmark and Canadas Price Edwards Island there is a ban on all beverage containers that cannot be reused. In Finland 95% of soft drink and alcoholic beverages are refillable (Germany 75%). In Finland 95% of soft drink and alcoholic beverages are refillable (Germany 75%).

20 REUSE Reducing resource waste: energy consumption for different types of 350-ml (12-oz) beverage containers. Reducing resource waste: energy consumption for different types of 350-ml (12-oz) beverage containers. Figure 22-7

21 Fig. 22-7, p. 525 Energy (thousands of kilocalories) Refillable drink bottle, used 10 times Recycled glass drink bottle Recycled aluminum can Glass drink bottle, used once Aluminum can, used once Recycled steel can Steel can, used once

22 How Would You Vote? Do you support banning all beverage containers that cannot be reused as Denmark has done? Do you support banning all beverage containers that cannot be reused as Denmark has done? a. No. Reused containers may be unsanitary. a. No. Reused containers may be unsanitary. b. Yes. A ban will save energy, money, and resources and result in a cleaner environment. b. Yes. A ban will save energy, money, and resources and result in a cleaner environment.

23 Solutions: Other Ways to Reuse Things We can use reusable shopping bags, food containers, and shipping pallets, and borrow tools from tool libraries. We can use reusable shopping bags, food containers, and shipping pallets, and borrow tools from tool libraries. Many countries in Europe and Asia charge shoppers for plastic bags. Many countries in Europe and Asia charge shoppers for plastic bags.

24 How Would You Vote? Should consumers have to pay for plastic or paper bags at grocery and other stores? Should consumers have to pay for plastic or paper bags at grocery and other stores? a. No. Instead, give discounts to people who bring their own bags. a. No. Instead, give discounts to people who bring their own bags. b. Yes. Making consumers buy their bags will reduce waste. b. Yes. Making consumers buy their bags will reduce waste.

25 Fig. 22-8, p. 526 Buy beverages in refillable glass containers instead of cans or throwaway bottles. Give or sell items you no longer use to others. Buy used furniture, computers, cars, and other items. Use reusable sponges and washable cloth napkins, dishtowels, and handkerchiefs instead of throwaway paper ones. Carry groceries and other items in a reusable basket, a canvas or string bag, or a small cart. Use rechargeable batteries and recycle them when their useful life is over. Carry sandwiches and store food in the refrigerator in reusable containers instead of wrapping them in aluminum foil or plastic wrap Use reusable plastic or metal lunchboxes. What Can You Do? Reuse

26 RECYCLING Primary (closed loop) recycling: materials are turned into new products of the same type. Primary (closed loop) recycling: materials are turned into new products of the same type. Secondary recycling: materials are converted into different products. Secondary recycling: materials are converted into different products. Used tires shredded and converted into rubberized road surface. Used tires shredded and converted into rubberized road surface. Newspapers transformed into cellulose insulation. Newspapers transformed into cellulose insulation.

27 RECYCLING There is a disagreement over whether to mix urban wastes and send them to centralized resource recovery plants or to sort recyclables for collection and sale to manufacturers as raw materials. There is a disagreement over whether to mix urban wastes and send them to centralized resource recovery plants or to sort recyclables for collection and sale to manufacturers as raw materials. To promote separation of wastes, 4,000 communities in the U.S. have implemented pay- as-you-throw or fee-per-bag waste collection systems. To promote separation of wastes, 4,000 communities in the U.S. have implemented pay- as-you-throw or fee-per-bag waste collection systems.

28 How Would You Vote? Should households and businesses be charged for the amount of mixed waste picked up but not charged for pickup of materials separated for recycling? Should households and businesses be charged for the amount of mixed waste picked up but not charged for pickup of materials separated for recycling? a. No. It would encourage illegal dumping and burning of wastes. a. No. It would encourage illegal dumping and burning of wastes. b. Yes. Consumer source separation saves money and makes consumers more conscientious. b. Yes. Consumer source separation saves money and makes consumers more conscientious.

29 RECYCLING Composting biodegradable organic waste mimics nature by recycling plant nutrients to the soil. Composting biodegradable organic waste mimics nature by recycling plant nutrients to the soil. Recycling paper has a number of environmental (reduction in pollution and deforestation, less energy expenditure) and economic benefits and is easy to do. Recycling paper has a number of environmental (reduction in pollution and deforestation, less energy expenditure) and economic benefits and is easy to do.

30 RECYCLING Recycling many plastics is chemically and economically difficult. Recycling many plastics is chemically and economically difficult. Many plastics are hard to isolate from other wastes. Many plastics are hard to isolate from other wastes. Recovering individual plastic resins does not yield much material. Recovering individual plastic resins does not yield much material. The cost of virgin plastic resins in low than recycled resins due to low fossil fuel costs. The cost of virgin plastic resins in low than recycled resins due to low fossil fuel costs. There are new technologies that are making plastics biodegradable. There are new technologies that are making plastics biodegradable.

31 How Would You Vote? Should we place much greater emphasis on recycling with the goal of recycling at least 60% of the municipal solid waste that we produce? Should we place much greater emphasis on recycling with the goal of recycling at least 60% of the municipal solid waste that we produce? a. No. Recycling programs should be market driven rather than setting unrealistically high goals that will either fail or require support from already overtaxed citizens. a. No. Recycling programs should be market driven rather than setting unrealistically high goals that will either fail or require support from already overtaxed citizens. b. Yes. High recycling rates will reduce pollution and save energy. b. Yes. High recycling rates will reduce pollution and save energy.

32 RECYCLING Reuse and recycling are hindered by prices of goods that do not reflect their harmful environmental impacts, too few government subsidies and tax breaks, and price fluctuations. Reuse and recycling are hindered by prices of goods that do not reflect their harmful environmental impacts, too few government subsidies and tax breaks, and price fluctuations.

33 How Would You Vote? Should governments pass laws requiring manufacturers to take back and reuse or recycle all packaging waste, appliances, electronic equipment, and motor vehicles at the end of their useful lives? Should governments pass laws requiring manufacturers to take back and reuse or recycle all packaging waste, appliances, electronic equipment, and motor vehicles at the end of their useful lives? a. No. These regulations would increase prices for consumers. a. No. These regulations would increase prices for consumers. b. Yes. The regulations would promote the manufacturing of more environmentally friendly products and further protect the environment. b. Yes. The regulations would promote the manufacturing of more environmentally friendly products and further protect the environment.

34 Fig. 22-9, p. 529 Important part of economy Source separation is inconvenient for some people Reduces profits from landfills and incinerators Reduces air and water pollution Saves energy Reduces mineral demand Reduces greenhouse gas emissions Reduces solid waste production and disposal Helps protect biodiversity Can save money for items such as paper, metals, and some plastics Does not save landfill space in areas with ample land May lose money for items such as glass and most plastic DisadvantagesAdvantages Trade-Offs Recycling

35 BURNING AND BURYING SOLID WASTE Globally, MSW is burned in over 1,000 large waste-to-energy incinerators, which boil water to make steam for heating water, or space, or for production of electricity. Globally, MSW is burned in over 1,000 large waste-to-energy incinerators, which boil water to make steam for heating water, or space, or for production of electricity. Japan and a few European countries incinerate most of their MSW. Japan and a few European countries incinerate most of their MSW.

36 Burning Solid Waste Waste-to-energy incinerator with pollution controls that burns mixed solid waste. Waste-to-energy incinerator with pollution controls that burns mixed solid waste. Figure 22-10

37 Fig , p. 530 Crane Hazardous waste landfill Waste treatment Conventional landfill Waste pit Bottom ash Fly ash Conveyor Water added Dirty water Furnace Wet scrubber Electrostatic precipitator Boiler Smokestack Electricity Steam Turbine Generator

38 Fig , p. 531 Reduces trash volume Can compete with recycling for burnable materials such as newspaper Output approach that encourages waste production Older or poorly managed facilities can release large amounts of air pollution Some air pollution Difficult to site because of citizen opposition Costs more than short-distance hauling to landfills Expensive to build Some facilities recover and sell metals Modern controls reduce air pollution Sale of energy reduces cost Concentrates hazardous substances into ash for burial or use as landfill cover Low water pollution Less need for landfills Trade-Offs Incineration AdvantagesDisadvantages

39 How Would You Vote? Do the advantages of incinerating solid waste outweigh the disadvantages? Do the advantages of incinerating solid waste outweigh the disadvantages? a. Yes. Incineration is a sanitary and effective method for eliminating infectious and organic wastes. a. Yes. Incineration is a sanitary and effective method for eliminating infectious and organic wastes. b. No. Incineration can generate toxic air pollution and ashes. b. No. Incineration can generate toxic air pollution and ashes.

40 Burying Solid Waste Most of the worlds MSW is buried in landfills that eventually are expected to leak toxic liquids into the soil and underlying aquifers. Most of the worlds MSW is buried in landfills that eventually are expected to leak toxic liquids into the soil and underlying aquifers. Open dumps: are fields or holes in the ground where garbage is deposited and sometimes covered with soil. Mostly used in developing countries. Open dumps: are fields or holes in the ground where garbage is deposited and sometimes covered with soil. Mostly used in developing countries. Sanitary landfills: solid wastes are spread out in thin layers, compacted and covered daily with a fresh layer of clay or plastic foam. Sanitary landfills: solid wastes are spread out in thin layers, compacted and covered daily with a fresh layer of clay or plastic foam.

41 Fig , p. 532 Sand When landfill is full, layers of soil and clay seal in trash Methane storage and compressor building Leachate storage tank Leachate monitoring well Groundwater monitoring well Electricity generator building Leachate treatment system Methane gas recovery well Compacted solid waste Leachate pipes Leachate pumped up to storage tank for safe disposal Groundwater Clay and plastic lining to prevent leaks; pipes collect leachate from bottom of landfill Topsoil Sand Clay Subsoil Probes to detect methane leaks Garbage Synthetic liner Sand Clay Pipes collect explosive methane as used as fuel to generate electricity

42 Fig , p. 533 No open burning Trade-Offs Sanitary Landfills AdvantagesDisadvantages Eventually leaks and can contaminate groundwater Discourages recycling, reuse, and waste reduction Slow decomposition of wastes Groundwater contamination Releases greenhouse gases (methane and CO2) unless they are collected Air pollution from toxic gases and volatile organic compounds Dust Noise and traffic No shortage of landfill space in many areas Filled land can be used for other purposes Can handle large amounts of waste Can be built quickly Low operating costs Low groundwater pollution if sited properly Little odor

43 How Would You Vote? Do the advantages of burying solid waste in sanitary landfills outweigh the disadvantages? Do the advantages of burying solid waste in sanitary landfills outweigh the disadvantages? a. No. Ultimately, landfills leak and pollute the environment. a. No. Ultimately, landfills leak and pollute the environment. b. Yes. They have relatively low operating costs, can store large amounts of waste, and are designed to prevent pollution. b. Yes. They have relatively low operating costs, can store large amounts of waste, and are designed to prevent pollution.

44 Case Study: What Should We Do with Used Tires? We face a dilemma in deciding what to so with hundreds of millions of discarded tires. We face a dilemma in deciding what to so with hundreds of millions of discarded tires. Figure 22-14

45 HAZARDOUS WASTE Hazardous waste: is any discarded solid or liquid material that is toxic, ignitable, corrosive, or reactive enough to explode or release toxic fumes. Hazardous waste: is any discarded solid or liquid material that is toxic, ignitable, corrosive, or reactive enough to explode or release toxic fumes. The two largest classes of hazardous wastes are organic compounds (e.g. pesticides, PCBs, dioxins) and toxic heavy metals (e.g. lead, mercury, arsenic). The two largest classes of hazardous wastes are organic compounds (e.g. pesticides, PCBs, dioxins) and toxic heavy metals (e.g. lead, mercury, arsenic).

46 Fig , p. 534 What Harmful Chemicals Are in Your Home? Glues and cements Dry-cell batteries (mercury and cadmium) Rust inhibitor and rust remover Brake and transmission fluid General Cleaning Battery acid Wood preservatives Stains, varnishes, and lacquers Automotive Gasoline Used motor oil Paint Latex and oil-based paints Paint thinners, solvents, and strippers Gardening Pesticides Weed killers Ant and rodent killers Antifreeze Flea powders Disinfectants Septic tank cleaners Spot removers Drain, toilet, and window cleaners Artist paints and inks Solvents

47 Hazardous Waste Regulations in the United States Two major federal laws regulate the management and disposal of hazardous waste in the U.S.: Two major federal laws regulate the management and disposal of hazardous waste in the U.S.: Resource Conservation and Recovery Act (RCRA) Resource Conservation and Recovery Act (RCRA) Cradle-to-the-grave system to keep track waste.Cradle-to-the-grave system to keep track waste. Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) Commonly known as Superfund program.Commonly known as Superfund program.

48 Hazardous Waste Regulations in the United States The Superfund law was designed to have polluters pay for cleaning up abandoned hazardous waste sites. 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. 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.

49 How Would You Vote? Should the U.S. Congress reinstate the polluter-pays principle by using taxes from chemical, oil, mining, and smelting companies to reestablish a fund for cleaning up existing and new Superfund sites? Should the U.S. Congress reinstate the polluter-pays principle by using taxes from chemical, oil, mining, and smelting companies to reestablish a fund for cleaning up existing and new Superfund sites? a. No. All taxpayers, not certain industries, should pay for cleaning up sites polluted in the past. a. No. All taxpayers, not certain industries, should pay for cleaning up sites polluted in the past. b. Yes. Funding for Superfund is needed and waste-generating industries rather than ordinary citizens should fund it. b. Yes. Funding for Superfund is needed and waste-generating industries rather than ordinary citizens should fund it.

50 DEALING WITH HAZARDOUS WASTE We can produce less hazardous waste and recycle, reuse, detoxify, burn, and bury what we continue to produce. We can produce less hazardous waste and recycle, reuse, detoxify, burn, and bury what we continue to produce. Figure 22-16

51 Fig , p. 536 Ocean and atmospheric assimilation Produce Less Waste Recycle and reuse Convert to Less Hazardous or Nonhazardous Substances Manipulate processes to eliminate or reduce production Land treatment Landfill Incineration Thermal treatment Put in Perpetual Storage Underground injection Waste piles Surface impoundments Salt formations Arid region unsaturated zone Chemical, physical, and biological treatment

52 Conversion to Less Hazardous Substances Physical Methods: using charcoal or resins to separate out harmful chemicals. Physical Methods: using charcoal or resins to separate out harmful chemicals. Chemical Methods: using chemical reactions that can convert hazardous chemicals to less harmful or harmless chemicals. Chemical Methods: using chemical reactions that can convert hazardous chemicals to less harmful or harmless chemicals.

53 Conversion to Less Hazardous Substances Biological Methods: Biological Methods: Bioremediation: bacteria or enzymes help destroy toxic and hazardous waste or convert them to more benign substances. 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. Phytoremediation: involves using natural or genetically engineered plants to absorb, filter and remove contaminants from polluted soil and water.

54 Phytostabilization Plants such as willow trees and poplars can absorb chemicals and keep them from reaching groundwater or nearby surface water. Rhizofiltration Roots of plants such as sunflowers with dangling roots on ponds or in green- houses can absorb pollutants such as radioactive strontium- 90 and cesium-137 and various organic chemicals. 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. 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. Inorganic metal contaminants Organic contaminants Radioactive contaminants Brake fern Poplar tree Indian mustard Willow tree Sunflower Oil spill Landfill Groundwater Soil Polluted leachate Decontaminated water out Polluted groundwater in Groundwater Soil

55 Fig , p. 538 Inexpensive Low energy use Easy to establish Trade-Offs Phytoremediation AdvantagesDisadvantages Some plants can become toxic to animals Some toxic organic chemicals may evaporate from plant leaves Produces little air pollution compared to incineration Can reduce material dumped into landfills Slow (can take several growing seasons) Effective only at depth plant roots can reach

56 How Would You Vote? Do the advantages of using phytoremediation to detoxify hazardous waste outweigh the disadvantages? Do the advantages of using phytoremediation to detoxify hazardous waste outweigh the disadvantages? a. No. The process is often too slow and cannot remove contaminants below the root zones of the remediating plants. a. No. The process is often too slow and cannot remove contaminants below the root zones of the remediating plants. b. Yes. Plants can be effective in removing organics, radionuclides, and inorganic contaminants from soil and water. b. Yes. Plants can be effective in removing organics, radionuclides, and inorganic contaminants from soil and water.

57 Conversion to Less Hazardous Substances 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. 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.

58 Conversion to Less Hazardous Substances Plasma Torch: passing electrical current through gas to generate an electric arc and very high temperatures can create plasma. Plasma Torch: passing electrical current through gas to generate an electric arc and very high temperatures can create plasma. The plasma process can be carried out in a torch which can decompose liquid or solid hazardous organic material. The plasma process can be carried out in a torch which can decompose liquid or solid hazardous organic material.

59 Fig , p. 538 Advantages Trade-Offs Plasma Arc Small High cost Produces no toxic ash Can vaporize and release toxic metals and radioactive elements Can release particulates and chlorine gas Mobile. Easy to move to different sites Produces CO2 and CO Disadvantages

60 How Would You Vote? Do the advantages of using a plasma torch to detoxify hazardous waste outweigh the disadvantages? Do the advantages of using a plasma torch to detoxify hazardous waste outweigh the disadvantages? a. No. Plasma torches are expensive and the combustion byproducts may be harmful to the environment and humans. a. No. Plasma torches are expensive and the combustion byproducts may be harmful to the environment and humans. b. Yes. Plasma torches are convenient for disposing of hazardous wastes. b. Yes. Plasma torches are convenient for disposing of hazardous wastes.

61 Long-Term Storage of Hazardous Waste Hazardous waste can be disposed of on or underneath the earths surface, but without proper design and care this can pollute the air and water. Hazardous waste can be disposed of on or underneath the earths 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. Deep-well disposal: liquid hazardous wastes are pumped under pressure into dry porous rock far beneath aquifers. Surface impoundments: excavated depressions such as ponds, pits, or lagoons into which liners are placed and liquid hazardous wastes are stored. Surface impoundments: excavated depressions such as ponds, pits, or lagoons into which liners are placed and liquid hazardous wastes are stored.

62 Fig , p. 539 Safe method if sites are chosen carefully Trade-Offs Deep Underground Wells AdvantagesDisadvantages Encourages waste production Existing fractures or earthquakes can allow wastes to escape into groundwater Leaks from corrosion of well casing Leaks or spills at surface Low cost Easy to do Wastes can be retrieved if problems develop

63 How Would You Vote? Do the advantages of deep-well disposal of hazardous waste outweigh the disadvantages? Do the advantages of deep-well disposal of hazardous waste outweigh the disadvantages? a. No. The systems may leak and contaminate valuable soils, sediments, and groundwaters. a. No. The systems may leak and contaminate valuable soils, sediments, and groundwaters. b. Yes. Deep injection wells can be designed to permanently remove hazardous wastes from surface and near-surface environments. b. Yes. Deep injection wells can be designed to permanently remove hazardous wastes from surface and near-surface environments.

64 Fig , p. 539 Low construction costs Can store wastes indefinitely with secure double liners Groundwater contamination from leaking liners (or no lining) Trade-Offs Surface Impoundments Advantages Promotes waste production Disruption and leakage from earthquakes Overflow from flooding Air pollution from volatile organic compounds Wastes can be retrieved if necessary Can be built quickly Low operating costs Disadvantages

65 How Would You Vote? Do the advantages of storing hazardous wastes in surface impoundments outweigh the disadvantages? Do the advantages of storing hazardous wastes in surface impoundments outweigh the disadvantages? a. No. The environment should not be openly exposed to liquid hazardous wastes. a. No. The environment should not be openly exposed to liquid hazardous wastes. b. Yes. Surface impoundments are inexpensive solutions for at least the temporary storage of liquid wastes. b. Yes. Surface impoundments are inexpensive solutions for at least the temporary storage of liquid wastes.

66 Long-Term Storage of Hazardous Waste Long-Term Retrievable Storage: Some highly toxic materials cannot be detoxified or destroyed. Metal drums are used to stored them in areas that can be inspected and retrieved. Long-Term Retrievable Storage: Some highly toxic materials cannot be detoxified or destroyed. Metal drums are used to stored them in areas that can be inspected and retrieved. Secure Landfills: Sometimes hazardous waste are put into drums and buried in carefully designed and monitored sites. Secure Landfills: Sometimes hazardous waste are put into drums and buried in carefully designed and monitored sites.

67 Secure Hazardous Waste Landfill In the U.S. there are only 23 commercial hazardous waste landfills. In the U.S. there are only 23 commercial hazardous waste landfills. Figure 22-22

68 Fig , p. 540 Bulk waste Gas vent Topsoil Earth Plastic cover Clay cap Double leachate collection system Plastic double liner Impervious clay cap Leak detection system Reactive wastes in drums Groundwater monitoring well Groundwater Water table Earth Impervious clay Sand

69 Fig , p. 540 What Can You Do? Use pesticides in the smallest amount possible. Use less harmful substances instead of commercial chemicals for most household cleaners. For example use liquid ammonia to clean appliances and windows; vinegar to polish metals, clean surfaces, and remove stains and mildew; baking soda to clean household utensils, deodorize, and remove stains; borax to remove stains and mildew. Do not dispose of pesticides, paints, solvents, oil, antifreeze, or other products containing hazardous chemicals by flushing them down the toilet, pouring them down the drain, burying them, throwing them into the garbage, or dumping them down storm drains. Hazardous Waste

70 Case Study: Lead Lead is especially harmful to children and is still used in leaded gasoline and household paints in about 100 countries. Lead is especially harmful to children and is still used in leaded gasoline and household paints in about 100 countries. Figure 22-24

71 Fig , p. 541 Phase out leaded gasoline worldwide Solutions Prevention Lead Poisoning Control Wash fresh fruits and vegetables Test existing candles for lead Test for lead in existing ceramicware used to serve food Remove lead from TV sets and computer monitors before incineration or land disposal Remove leaded paint and lead dust from older houses and apartments Replace lead pipes and plumbing fixtures containing lead solder Ban candles with lead cores Ban lead glazing for ceramicware used to serve food Ban use of lead in computer and TV monitors Ban use of lead solder Test blood for lead by age 1 Phase out waste incineration Sharply reduce lead emissions from old and new incinerators

72 Case Study: Mercury Mercury is released into the environment mostly by burning coal and incinerating wastes and can build to high levels in some types of fish. Mercury is released into the environment mostly by burning coal and incinerating wastes and can build to high levels in some types of fish. Figure 22-26

73 Fig , p. 543 Solutions Mercury Pollution Phase out use of mercury in all products unless they are recycled Require labels on all products containing mercury Switch from coal to natural gas and renewable energy resources such as wind, solar cells, and hydrogen Convert coal to liquid or gaseous fuel Collect and recycle mercury- containing electric switches, relays, and dry-cell batteries Tax each unit of mercury emitted by coal-burning plants and incinerators Sharply reduce mercury emissions from coal-burning plants and incinerators PreventionControl Remove mercury from coal before it is burned Phase out waste incineration

74 Fig , p. 542 BIOMAGNIFICATION IN FOOD CHAIN SEDIMENT PRECIPITATION WINDS AIR WATER Inorganic mercury and acids (Hg 2+ ) Inorganic mercury and acids (Hg 2+ ) Organic mercury (CH 3 Hg + ) Inorganic mercury (Hg 2+ ) Hg 2+ and acids Runoff of Hg 2+ and acids Large fish Small fish ZooplanktonPhytoplankton Hg and SO 2 Hg 2 + and acids Human sources Incinerator Coal- burning plant Elemental mercury vapor (Hg) Photo- chemical Oxidation Elemental mercury liquid (Hg) Deposition Bacteria and acids Settles out Settles out Settles out Vaporization Deposition

75 ACHIEVING A LOW-WASTE SOCIETY In the U.S., citizens have kept large numbers of incinerators, landfills, and hazardous waste treatment plants from being built in their local areas. In the U.S., citizens have kept large numbers of incinerators, landfills, and hazardous waste treatment plants from being built in their local areas. Environmental justice means that everyone is entitled to protection from environmental hazards without discrimination. Environmental justice means that everyone is entitled to protection from environmental hazards without discrimination.

76 Global Outlook: International Action to Reduce Hazardous Waste An international treaty calls for phasing out the use of harmful persistent organic pollutants (POPs). An international treaty calls for phasing out the use of harmful persistent organic pollutants (POPs). POPs are insoluble in water and soluble in fat. POPs are insoluble in water and soluble in fat. Nearly every person on earth has detectable levels of POPs in their blood. Nearly every person on earth has detectable levels of POPs in their blood. The U.S has not ratified this treaty. The U.S has not ratified this treaty.

77 Making the Transition to a Low-Waste Society: A New Vision Everything is connected. Everything is connected. There is no away for the wastes we produce. There is no away for the wastes we produce. Dilution is not always the solution to pollution. Dilution is not always the solution to pollution. The best and cheapest way to deal with wastes are reduction and pollution prevention. The best and cheapest way to deal with wastes are reduction and pollution prevention.


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