Chapter 21: Solid, Toxic and Hazardous Waste Brita Christensen and Carlye Richter Case Study: South Africa’s “National Flower” -Some South Africans began referring to plastic bags as the country’s national flower -Each year shops hand out 8 billion light-weight, single-use bags -If they were thicker (80 microns) they would be reusable and litter would be reduced -Trade unions fear that current machines wouldn’t be able to make such bags, causing unemployment -If the bags were thicker, stores would charge more for them, making customers more likely to reuse Solid Waste The U.S. produces 11 billion tons per year ½ is agricultural waste 1/3 of all solid wastes are produced from mining and primary metal processing Road and building construction debris Improper disposal methods spread waste Industrial waste is 400 million metric tons a year 60 million of these are hazardous or toxic waste Municipal waste is 200 million + metric tons a year 2/3 of a ton per person Question! How many tons of solid waste does the U.S. produce every year!? The Waste Stream Definition: the steady flow of varied wastes that we all produce, from domestic garbage and yard wastes to industrial, commercial and construction refuse. Most of this waste could be valuable if it wasn’t mixed Hazardous materials spread through garbage making disposal processes more difficult, expensive and risky Examples of potentially hazardous trash: spray paint cans, pesticides, batteries, cleaning solvents, dioxin releasing plastics Question! What is one example of potentially hazardous trash!? Waste Disposal Methods Open Dumps Release Hazardous Materials Into Air and Water --The Three “R’s” Toxic chemicals are showing up in groundwater supplies that ½ of America depends on for drinking -Theoretically, one liter of gasoline could make a million liters of water undrinkable Open, unregulated dumps are predominant in most developing countries Mexico City produces 10,000 tons of trash a day Manila, Philippines –half of their waste collects in “Smoky Mountain” -20,000 people live and work there Open dumping has been banned in most places, but illegal dumping is still a problem 200 million L of motor oil are illegally dumped a year –5 times the amount spilled from Exxon Valdez, 1989 Ocean Dumping is Nearly Uncontrollable -25,000 metric tons (55 million lbs.) of packaging a year are dumped at sea. -Federal legislation prohibits dumping of municipal refuse, industrial waste, sewage and sewage sludge in the ocean -60-80 million m3 of dredge spoil are disposed of at sea. Landfills Receive Most of Our Waste -Sanitary landfills are an alternative to open dumps -This method regulates and controls solid waste disposal -landfill operators are required to compact the refuse and cover it with a layer of dirt, this controls pollution but also takes up 20% of landfill space -An impermeable clay and/or plastic lining underlies and encloses the storage area in landfills -Drainage systems surrounding the liner catch drainage and monitor chemicals that may be leaking -location is essential to landfills, demonstrating concern for long-term effects associated with this form of disposal Question! What is an alternative to open dumps!? More on Landfills … -The U.S. spends $10 billion a year to dispose of trash -1,200 of the 1,500 existing landfills in the U.S. have closed since stricter financial and environmental protection requirements for landfills took effect in 1984 -Cities have begun exporting trash which is expensive -Methane –an important GHG is important to recover. -It seeps to the surface of a landfill and escapes, but now it is collected and burned. -Landfills could provide enough electricity for a city of a million people Question! How much money does the U.S spend per year on disposing of trash!? Exporting Waste Exposes Villagers to Hazards Most industrialized nations have agreed to stop shipping hazardous and toxic waste to less-developed countries The Taiwan village disaster Poor neighborhoods and minority populations are much more likely than richer ones to be the recipients of dumps, waste incinerators, and other locally unwanted land uses (LULUs) One method of disposing of toxic wastes is to recycle them Manufacturers are now required to report the “active” ingredient content of their product, but much can go unreported as “inert” matter Incineration Produces Energy but Causes Pollution Burning serves as an alternative to landfills Energy-recovery Refuse-derived fuel Mass burn Incinerators are costly, but can also extend the lifetime of existing landfills EPA found high levels of toxic substances in incinerator ash –more in the fly ash than others EPA says the danger is small, and causes 1 death per million people every 70 years, though critics claim it to be 250 per million To reduce dangers, remove batteries containing heavy metals and plastics containing chlorine before incineration (eliminates majority of dioxins and other by-products) Question! What is one advantage of incinerators? Shrinking the Waste Stream • Recycling means reusing, but also reprocessing • One problem for recyclers is the fluctuation in market prices for commodities • Another problem is contamination (ex: soda bottles) • Plastic recycling is down 50% due to “on the go” packaging • Recycling is the best alternative because it saves money, energy, raw materials, and land space • Encourages individual awareness and responsibility • Recycling has quadrupled since 1980, right now Japan is the world’s leader, recycling ½ of it’s municipal waste • When waste is well sorted, recycling is most successful • Recycling reduces our need for raw resources • Although public policy favors the use of raw material now, government statutes are working to change that Commercial-scale Recycling and Composting Composting is the most common form of large-scale recycling Cities and towns have begun providing compost facilities to save landfill space Organic debris is 12% of our waste stream, and ½ of organic waste is composted An increasing number of the thousands of tons of debris sent to landfills is being collected, sorted and resold Thermal conversion Process (TCP) De-manufacturing • Definition: the disassembly and recycling of obsolete products like TV sets, computers, refrigerators and air conditioners. Electronics and appliances are one of the fastest-growing components of the global waste stream • E-waste –computers, cell phones, TVs and printers • A single computer can contain 70 different chemical compounds • 40% of lead and 70% of heavy metals come from e-waste • Some nations have taken the initiative in reducing these environmental hazards Question! What is an example of Ewaste? Reusing vs. Recycling Reusing is better than recycling The reusable, refillable bottle is the most efficient beverage container we have Big companies prefer recyclable containers over reusable containers because they are more cost efficient In some cases, reusing is not energy efficient Where manufactured products are expensive and labor is cheap, it pays to reuse Question! Which is better: reusing or recycling? Reducing Waste is Often the Cheapest Option • Excess packaging of food and consumer products is one of our greatest sources of unnecessary waste • Paper, plastic, glass and metal packaging material make up 50% of our domestic trash by volume • Most packaging is primarily for marketing purposes • Canada’s National Packaging Protocol (NPP) • 1) no packaging 2) minimal packaging 3) reusable packaging 4) recyclable packaging • -Photodegradable plastics • Biodegradable plastics • Both are compostable or degradable • Sometimes materials don’t decompose completely • The most effective way to save energy, materials, and money is to slow the consumption of throwaway products Hazardous Waste Must be Recycled, Contained or Detoxified • Hazardous waste –any discarded material, liquid or solid, that contains substances known to be (1) fatal to humans or laboratory animals in low doses (2) toxic, carcinogenic, mutagenic, or teratogenicto humans or other life-forms (3) ignitable with a flash point less than 60 degrees Celsius (4) corrosive or (5) explosive or highly reactive Most hazardous waste is recycled, converted to nonhazardous forms, stored or otherwise disposed of onsite by the generators 5 billion metric tons of highly poisonous chemicals were improperly disposed of in the U.S. between 1950 and 1975 Hazardous and Toxic Wastes • The most dangerous aspect of the waste stream is that it often contains highly toxic and hazardous materials that are injurious to both human health and environmental quality • The EPA states that industries in the U.S. generate about 265 million metric tons of officially classified hazardous wastes each year, slightly more than 1 ton for each person in the country • 40 million metric tons (22billion lbs.) of toxic and hazardous wastes are released into the air, water, and land in the U.S. a year Question! Why is the waste stream so dangerous? Federal Legislation • The Resource Conservation and Recovery ACT of 2976 • The Comprehensive Environmental Response, Compensation and Liability Act (CERCLA or Superfund ACT) of 1980 (modified in 1984 by the Superfund Amendments and Reauthorization Act (SARA)) • The Toxic Release Inventory requires more 20,000 manufacturing facilities to report annually on releases of more than 300 toxic materials Superfund Sites are Those Listed for Federal Cleanup • The EPA estimates that there are at least 36,000 seriously contaminated sites in the U.S. • The GAO says it’s higher (400,000 +) • By 1997 1,400 sites were on the NPL (National Priority List) for cleanup financed by the federal Superfund program • Superfund –a revolving pool designed to (1) provide an immediate response to emergency situations that pose imminent hazards and (2) to clean up or remediate abandoned or inactive sites Case Study #2: Hardeman County, Tennessee • The chemical build up began when William T. Love left his project of a man-made canal unfinished • Hooker Chemicals Corp. used this as a landfill • The runoff started emerging throughout the community • The seepage caused adverse effects among community members • Some included: birth defects, miscarriages, still births, cancers, heart diseases, nervous system defects and other health related issues • The tragedy was resolved only after many activist efforts Brownfields Large areas of contaminated properties that have been abandoned or are not being used up to their potential because of real or suspected pollution No one wanted to redevelop brownfields because of liability Question! Why does no one want to redevelop brownfields? Redeveloping Brownfields Reusing contaminated properties can rebuild old cities, create jobs, increase the tax base, and prevent needless destruction of open space at urban margins Programs have been established at the federal and state levels to encourage brownfield recycling Must pass EPA standards What do we do with toxic and hazardous wastes? Produce less waste! Modify manufacturing processes, recycle, and reuse material Convert to less hazardous substances! (several processes to make hazardous materials less toxic) Physical treatments- tie up or isolate substances Incineration- burning wastes Chemical processing- transform materials into nontoxic Bioremediation- uses microorganisms to absorb, accumulate, and detoxify toxic compounds What else do we do with toxic and hazardous wastes? Store permanently! Permanent retrievable storage- placing waste storage containers in a secure building, salt mine, or bedrock cavern where they can be inspected periodically and retrieved for repacking or for transfer Secure landfills- must be safe Thick bottom cushion of compacted clay Layer of gravel over the clay and drain pipes to collect seepage Thick polyethylene liner Layer of soil or absorbent sand cushions Wastes packed in drums, separated into small units Question! What is one method of disposing of hazardous wastes?