ENVIRONMENTAL SCIENCE CHAPTER 16: Solid and Hazardous Waste
Core Case Study: Electronic Waste What is electronic waste or e-waste? Fastest growing category of waste ____% recyclable Contains toxic materials
Fig. 16-1, p. 403
Wasting Resources (1) Solid Waste Industrial solid waste __________________ Municipal solid waste Concept 16-1 Solid waste represents pollution and unnecessary waste of resources, and hazardous waste contributes to pollution, natural capital degradation, health problems, and premature deaths.
Wasting Resources (2) Hazardous or toxic waste Threatens human health or environment Poisonous Reactive Corrosive Flammable Developed countries produce ________%
Wasting Resources (3) Solid waste and hazardous waste About ____ unnecessary resource waste Create air & water pollution, land degradation
What Harmful Chemicals Are in Your Home? Cleaning Disinfectants Drain, toilet, and window cleaners Spot removers Septic tank cleaners Gardening Pesticides Weed killers Ant and rodent killers Flea powders Paint Products Paints, stains, varnishes, and lacquers Paint thinners, solvents, and strippers Wood preservatives Artist paints and inks Automotive Gasoline Used motor oil Antifreeze Battery acid Brake and transmission fluid General Dry-cell batteries (mercury and cadmium) Glues and cements Stepped Art Fig. 16-2, p. 405
Fig. 16-3, p. 405
Case Study: Solid Waste in the United States Produces ____ of world’s solid waste Mining, agricultural, industrial: _____% Municipal solid waste: _____% High-waste economy Examples?
sustainable approach to solid waste Waste management Waste reduction reduce it! Integrated waste management then reuse or recycle it & safely dispose of what is left
To manufacturers for reuse or for recycling Compost Landfill Raw materials Processing and manufacturing Products Solid and hazardous wastes generated during the manufacturing process Waste generated by households and businesses Food/yard waste Hazardous waste Remaining mixed waste Plastic Glass Metal Paper To manufacturers for reuse or for recycling Hazardous waste management Compost Landfill Incinerator Fertilizer Fig. 16-4, p. 407
First Priority Second Priority Last Priority Primary Pollution and Waste Prevention Change industrial process to eliminate use of harmful chemicals Use less of a harmful product Reduce packaging and materials in products Make products that last longer and are recyclable, reusable, or easy to repair Second Priority Second Pollution and Waste Prevention Reuse Repair Recycle Compost Buy reusable and recyclable products Last Priority Waste Management Treat waste to reduce toxicity Incinerate waste Bury waste in landfills Release waste into environment for dispersal or dilution Stepped Art Fig. 16-5, p. 407
Fig. 16-6, p. 408
Science Focus: Garbology Garbologists Like archaeologists Trash persists for decades
Why Is Reusing and Recycling Materials So Important? Reusing items: decreases use of matter & energy resources reduces pollution & natural capital degradation recycling does so to a lesser degree
Reuse Reuse as a form of waste reduction Salvaging Yard sales, flea markets, secondhand stores, auctions, newspaper ads, Craigslist, ebay Technology: rechargeable batteries Refillable containers and cloth bags
Fig. 16-7, p. 409
5 major types of materials can be recycled ________________________
Recycling Primary (closed-loop) recycling Secondary recycling Pre-consumer (internal) waste Post-consumer (external) waste Feasibility and marketing
Mixed vs Separate Household Recycling Material recovery facilities (MRF) ___________________________ Source separation By households and businesses ______________________________________________________________________
Composting Decomposing bacteria Household composting Organic waste collection facilities Successful large-scale composting
Individuals Matter: Recycling Plastics _____% plastics recycled MBA Polymers, Inc – commercial recycling process Mike Biddle and Trip Allen, co-founders Pellets cheaper than virgin plastics More environmentally friendly
Trade-Offs Recycling Advantages Disadvantages 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 landfill space Important part of economy Can cost more than burying in areas with ample landfill space May lose money for items such as glass and some plastics Reduces profits for landfill and incinerator owners Source separation is inconvenient for some people Fig. 16-8, p. 411
Science Focus: Bioplastics Most plastics are organic polymers produced from petrochemicals Bioplastics made from plant materials Biodegradable Composting
Encouraging Reuse & Recycling Market prices must reflect true costs Even economic playing field: _____________________________ Stabilize prices for recycled materials _______________________________ ______________________________
disposal in landfill, or use as landfill cover Electricity Smokestack Turbine Steam Crane Generator Electrostatic precipitator Furnace Wet scrubber Boiler Water added Waste pit Dirty water Conveyor Bottom ash Fly ash Ash for treatment, disposal in landfill, or use as landfill cover Fig. 16-9, p. 413
Trade-Offs Incineration Disadvantages Advantages Reduces trash volume Less need for landfills Low water pollution Concentrates hazardous substances into ash for burial Sale of energy reduces cost Modern controls reduce air Some facilities recover and sell metals Expensive to build Costs more than short-distance hauling to landfills Difficult to site because of citizen opposition Some air pollution and CO2 emissions Older or poorly managed facilities can release large amounts of air pollution Output approach that encourages waste production Can compete with recycling for burnable materials such as newspaper Fig. 16-10, p. 414
Burying Solid Wastes Open dumps Sanitary landfills Leachates
Pipes collect explosive methane for use as fuel When landfill is full, layers of soil and clay seal in trash Topsoil Sand Methane storage and compressor building Clay Electricity generator building Leachate treatment system Garbage Probes to detect methane leaks Methane gas recovery well Pipes collect explosive methane for use as fuel to generate electricity Leachate storage tank Compacted solid waste Groundwater monitoring well Leachate pipes Garbage Leachate pumped up to storage tank for safe disposal Sand Synthetic liner Leachate monitoring well Sand Groundwater Clay and plastic lining to prevent leaks; pipes collect leachate from bottom of landfill Clay Subsoil Fig. 16-11, p. 414
Trade-Offs Sanitary Landfills Advantages Disadvantages No open burning Noise and traffic Little odor Dust Low groundwater pollution if sited properly Air pollution from toxic gases and trucks Can be built quickly Releases greenhouse gases (methane and CO2) unless they are collected Low operating costs Can handle large amounts of waste Slow decomposition of wastes Filled land can be used for other purposes Output approach that encourages waste production No shortage of landfill space in many areas Eventually leaks and can contaminate groundwater Fig. 16-12, p. 415
Integrated hazardous waste management Produce Less Hazardous Waste Change industrial processes to reduce or eliminate hazardous waste production Recycle and reuse hazardous waste Convert to Less Hazardous or Nonhazardous Substances Natural decomposition Incineration Thermal treatment Chemical, physical, and biological treatment Dilution in air or water Put in Perpetual Storage Landfill Underground injection wells Surface impoundments Underground salt formations Stepped Art Fig. 16-13, p. 415
Detoxifying Hazardous Waste Bioremediation Phytoremediation Incineration Plasma arc torch
Storing Hazardous Waste Deep-well disposal __________________________________________ Surface impoundments ______ % in U.S. have _______________________ ______ % may threaten ______________________ Secure landfills
Fig. 16-14, p. 417
Trade-Offs Surface Impoundments Advantages Disadvantages Low construction costs Groundwater contamination from leaking liners (or no lining) Low operating costs Air pollution from volatile organic compounds Overflow from flooding Can be built quickly Wastes can often be retrieved if necessary Disruption and leakage from earthquakes Can store wastes indefinitely with secure double liners Output approach that encourages waste production Fig. 16-15, p. 417
Bulk waste Gas vent Topsoil Plastic cover Earth Sand Impervious clay cap Clay cap impervious clay Water table Figure 16.16: Solutions: secure hazardous waste landfill. Earth Leak detection system Groundwater Double leachate collection system Plastic double liner Reactive wastes in drums Groundwater monitoring well Fig. 16-16, p. 418
Fig. 16-17, p. 418
Hazardous Waste Regulation in USA Resource Conservation & Recovery Act EPA administers Cradle to grave Laws regulate only ____% of hazardous wastes
Superfund 1980 - created Cleans hazardous waste sites Nov. 2008: 1,255 sites on list; 322 sites cleaned Now broke Who pays for clean up?
Brownfields Turning toxic areas into parks and nature reserves
Dealing with Lead (Pb) Poisoning Neurotoxin Especially harmful to children 1976-2004: # children with unsafe blood Pb levels dropped from _____% to _____% Gov’t banned ________________________ ____________________________________ _____ countries still use leaded gasoline
Solutions Lead Poisoning Prevention Control Phase out leaded gasoline worldwide Phase out waste incineration Ban use of lead solder in computer and TV monitors Ban lead glazing for ceramicware used to serve food Test blood for lead by age 1 Replace lead pipes and plumbing fixtures containing lead solder Remove leaded paint and lead dust from older houses and apartments Sharply reduce lead emissions from incinerators Remove lead from TV sets and computer monitors before incineration or land disposal Test for lead in existing ceramic-ware used to serve food Ban candles withlead cores Test existing candles for lead Wash fresh fruits and vegetables Fig. 16-18, p. 419
Achieving a Low-Waste Society Grassroots action Environmental justice International treaties Basel Convention Persistent organic pollutants (POPs)
Five Principles for Achieving a Low-Waste Society Everything is connected There is no “away” for wastes Polluters & producers must pay for wastes Different categories of hazardous waste and recyclable waste should not be mixed Reuse, recycle, & compost solid wastes
Three Big Ideas from This Chapter: #1 order of priorities for dealing with solid waste should be:
Three Big Ideas from This Chapter: #2 Order of priorities for dealing with hazardous waste should be:
Three Big Ideas from This Chapter: #3 We need to view solid wastes as wasted resources and hazardous wastes as materials that we should not be producing in the first place.