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SOLID WASTE. Statistics. Solid waste produced by one person Each day…about 4.5-5 pounds Each year… 1,825 pounds In a 70 year lifespan…127,750 pounds 180 million metric tons of solid waste is disposed of per year in the U.S. Solid Waste. 98.5% is from 1. Mining 2. Oil and gas production
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Statistics • Solid waste produced by one person • Each day…about 4.5-5 pounds • Each year… 1,825 pounds • In a 70 year lifespan…127,750 pounds • 180 million metric tons of solid waste is disposed of per year in the U.S.
Solid Waste • 98.5% is from • 1. Mining • 2. Oil and gas production • 3. Agriculture • 4. Sewage treatment • 5. Industry • 1.5% is municipal solid waste (MSW)
Waste Stream • The steady flow of varied waste from domestic garbage and yard wastes to industrial, commercial and construction refuse. • Municipal Solid Waste (MSW) is domestic waste & is composed of…
Most refuse is mixed… • Makes separation an expensive process • Mixes hazardous waste with normal waste, making disposal or burning dangerous
History of Garbage Disposal • Hunters & gathers • ultimate composters • No packaging • All biodegradable
Open Dumps • 1st created in 500 B.C. in Athens, Greece • Outlawed in U.S. & many other MDC. Some illegal dumping still occurs • Still in use by most developing countries. • Mexico city produces 10,000 tons of trash each day. • Many poor families work these dumps to get food or recyclables for $ • Garbage is simply dumped anywhere. • Cons: • Attracts vermin & insects • Smells • Methane causes spontaneous fires (Smokey Mtn in Phillipines) • Aesthetic degredation
Ocean Dumping • 55 million lbs of bottles, cans, plastic are dumped at sea • 330 million lbs of fishing gear- lines, nets, etc. lost each year • New York did not stop dumping sewage until 1992!
Sanitary Landfills • #1 disposal method for majority of MSW in U.S. • Located on geologically stable areas- solid bedrock with impermeable soil • Now try to avoid areas near rivers, lakes, floodplains & aquifer recharge zones • Dig a large pit • Layers of clay and/or plastic form base of landfill • Prevents hazardous chemicals (oil, chemicals, metals, etc.) from leaching into soil • Drainage pipes may be added to remove leachate • Trash is added, compacted, then covered with soil • This deters vermin & reduces odor • Methane pipes & vents may be added to prevent methane build up that might result in explosions • When landfill is full, final layers of dirt are added, trees & plants are planted on mound. • Groundwater is monitored over time to check for leaking landfills
Sanitary Landfills • Cons: • NIMBY: Not In My Back Yard • Aesthetic degradation • Rising land prices & shipping costs • Running out of landfill space • Many places having to pay large sums to ship garbage to other communities • Demanding maintenance requirements/laws • Becoming more expensive
Garbage Imperialism • Sending waste to LDC or poor neighborhoods for disposal • Many communities try to sell waste to Indian reservations b/c they are not under same fed. regulations • Most MDC have agreed to stop shipping hazardous & toxic waste to LDC, but still occurs. • EX: 1999, Bel Trang, Cambodia received 3000 tons of incinerated plastic waste. Happy residents used packaging from waste for rice storage, bedding, roofing. Ended up with mercury poisoning. Plastic company paid a $3 million bribe to Cambodian officials to dispose of their waste. Went back to pick it up, but damage already done. • “Recycle” toxic material into something else. • Ex: toxic waste recycled into asphalt or concrete filler for building highways; phosphogypsum from phosphate mining is sold as soil amendment (fertilizer) which does help plants grow but is radioacitve
Incineration • Garbage is burned • Also used as energy recovery (waste to energy) when garbage burned to boil water, produce steam & create energy • Pros: • Reduce landfill space • Only bury ash • Extends life of a landfill • Cons: • Expensive • Air pollution • May be toxic ash residue- dioxin, furans, lead, cadmium • If used to create energy must have consistent stream of garbage so doesn’t work well in communities that recycle heavily.
Types of Incinerators • Refuse-derived fuel • Unburnable or recyclables are removed before burning • More time consuming & expensive • Creates less harmful emissions • Mass burn • Dump everything smaller than a sofa into burn pit • Less expensive, easier • Causes more air pollution & maintenance on chimneys
How can we shrink the waste stream so we don’t have to rely on disposal methods? • REDUCE! • REUSE! • RECYCLE! • In that order…
REDUCE • Reduce the amt of waste you generate- preferred method of waste reduction • Buy foods with less packaging • Bring your own bags for carrying groceries- no paper OR plastic • Bring your own bottles/cups • Look for products that use fewer toxins • If choosing between glass, metal or plastic- choose glass or metal • Preferred Hierarchy: • No packaging • Minimal packaging • Reusable packaging • Recyclable packaging • Compost your yard waste & kitchen scraps • If using plastic use photodegradable or biodegradable plastic • Cons: • Don’t go away completely • May add toxins to soil • Never decompose in sanitary landfill • People may think littering is OK
REDUCE • Since 1977, the weight of 2-liter plastic soft drink bottles has been reduced from 68 grams each to 51 grams • That means that 250 million pounds of plastic per year has been kept out of the waste stream
REUSE • Reuse/resell things that are still good • Auto parts sold thru junkyards- demanufacturing • Salvage parts (doors, stained glass) from old buildings • Some areas provide money to return bottles for refilling • Donate clothing/toys to charities that will sell them for money • Preferred over recycling because material doesn’t have to be reprocessed
RECYCLE • Reprocessing of discarded materials into new, useful products. • Recycle glass into other glass products • Recycle tires into rubberized road surfacing • Problems: • Plastic recyclables can be contaminated by one PVC bottle in a truckload • Plastic recycling is down 50% b/c so many people consume these bottles on the go. • Benefits: • Saves water, energy, raw materials, land space • Lowers demand for raw resources- less deforestation, mining • Producing aluminum from scrap instead of bauxite ore cuts energy need by 95% • Reduces pollution • Makes one think about waste they produce • Cut waste volumes & reduce pressure on landfills • Reduces litter problems
COMPOSTING • Breakdown of organic cmpds with aerobic bacteria • Can be used as organic fertilizer • Can include anything except meat or dairy • Benefits: • Keeps organic wastes out of landfills • Provides nutrients to the soil • Increases beneficial soil organisms (e.g., worms and centipedes) • Suppresses certain plant diseases • Reduces the need for fertilizers and pesticides • Protects soils from erosion
Energy from Waste • “Every year we throw away the energy equivalent of 80 million barrels of oil in organic waste in the U.S.” • Trap methane from landfill to use like natural gas • Burn garbage to create steam to create energy • Organic material can be digested in digester with bacteria that produce methane which can be used like natural gas (farms may use this with animal manure)
Hazardous waste • Any discarded material, liquid or solid that contains substances known to be… • Fatal to humans or lab animals in low doses • Toxic, carcinogenic, mutagenic, or teratogenic to humans or other life-forms • Ignitable with a flash point less than 60°C • Corrosive • Explosive or highly reactive • Biggest source of toxins are chemical & petroleum industries
Household Hazardous Waste • Common household items such as paints, cleaners, oils, batteries, and pesticides contain hazardous components • Labels – danger, warning, caution, toxic, corrosive, flammable, or poison identify products that might contain hazardous materials • Leftover portions of these products are called household hazardous waste (HHW) • These products, if mishandled, can be dangerous to your health and the environment
Proper Handling of HHW • The best way to handle HHW is to reduce the amount initially generated by giving leftover products to someone else to use • Many communities have set up collection programs to prevent HHW from being disposed of in MSW landfills and combustors • These programs ensure the safe disposal of HHW in facilities designed to treat or dispose of hazardous waste • More than 3,000 HHW collection programs exist in the United States
Resource Conservation and Recovery Act (RCRA)(all about prevention) • The Resource Conservation and Recovery Act (RCRA) was enacted by Congress in 1976 and amended in 1984. • Primary goal- to protect human health and the environment from the potential hazards of waste disposal. • In addition, RCRA calls for • conservation of energy and natural resources • reduction in waste generated • environmentally sound waste management practices. • Cradle to grave law- must keep record of hazardous waste from time created to time disposed of.
About Superfund • Years ago, people were less aware of how dumping chemical wastes might affect public health and the environment • On thousands of properties where such practices were intensive or continuous, the result was uncontrolled or abandoned hazardous waste sites, such as abandoned warehouses and landfills
About Superfund • Citizen concern over the extent of this problem led Congress to establish the Superfund Program in 1980 to locate, investigate, and clean up the worst sites nationwide • The EPA administers the Superfund program in cooperation with individual states and tribal governments • The office that oversees management of the program is the Office of Emergency and Remedial Response (OERR)
Superfund Legislation (all about the clean up) • Comprehensive Environmental Response, Compensation, and Liabilities Act (CERCLA); 1980 • “Superfund” to clean up abandoned sites • Hazard Ranking System (HRS) • National Priority List (NPL) • Qualifications… • Leaking or have potential for leaking toxins • Site contains: lead, trichloroethylene, toluene, benzene, PCB’s, chloroform, phenol, arsenic, cadmium, chromium • Reauthorized in 1986 (SARA) • Toxic Release Inventory- requires 20,000 manufacturing facilities to report annually on releases of more than 300 toxic materials.
Intended as a solution to those previously contaminated sites with no one to pay for clean up • Two levels • Emergency response • immediate threat to human health or environment • Long term remediation • if Hazard Ranking System (HRS) shows a score over 27.5, it is added to the National Priorities List (NPL) for Superfund cleanup • 1300 sites on NPL in 1990, more to come
Superfund sites in Georgia • http://www.epa.gov/superfund/sites/npl/ga.htm#Diamond_Shamrock_Corp._Landfill
Examples of Hazardous Waste Sites • Old industrial plants- smelters, mills, oil refineries (esp. around Great Lakes & Gulf Coast) • Mining districts, railyards, abandoned filling stations • Old dumps- indiscriminate dumping of many items • Love Canal in Niagara Falls, NY- community built on old dump holding 20,000 tons of toxins • Hardeman, TN- 250,000 barrels of chemical waste buried in shallow pits, leaked into water
Cleaning up Hazardous Waste Sites • Brownfields- areas of land that are not being used to potential b/c do have or may have pollutants in soil or water. • Columbia, Mississippi • 81 acres contaminated w/turpentine & pine tar • Concentrations of phenols above federal standards • Added to Superfund NPL site • Some experts recommended covering w/soil & enclosing w/fence • Instead, EPA made Reichhold Chemical (last owner of property) to pay $4 million to remove 12,500 tons of soil and replace with clean soil so may be used for homes • Took contaminated soil to a hazardous waste dump in Louisiana
Hazardous Waste Management & Disposal • Source reduction- don’t buy it or buy items that include toxic chemicals • Recycling reduces need for harmful chemicals • Waste exchange- one company gets rid of waste which is a raw material for another; both win- generator doesn’t pay disposal cost, recipient pays little for raw material • Convert to Less Hazardous Substance • Physical Treatment- charcoal or resin filters absorb toxins, metals & radioactive substances can be fused with silica to make stable, impermeable glass • Incineration- heating over 1000C for a period of time leads to complete destruction; ash is safer to store or uses less space • Chemical Processing- makes toxic material non-toxic; neutralization, oxidation, removal of metals • Bioremediation- microorganisms absorb, accumulate & detoxify; activated sludge basins, oil spills; better to keep in reaction vessels instead of releasing to env. • Stored Permanently • Retrievable Storage- secure building, salt mine, bedrock cavern (Yucca Mtn) so can accessed, checked on, removed If necessary; more expensive, must be guarded & monitored • Secure Landfills- similar to regular landfill but may be located on industry property