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Solid and Hazardous Waste. Chapter 22. Chapter Overview Questions. What is solid waste and how much do we produce? How can we produce less solid waste? What are the advantages and disadvantages of reusing recycled materials?
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Solid and Hazardous Waste Chapter 22
Chapter Overview Questions • What is solid waste and how much do we produce? • How can we produce less solid waste? • What are the advantages and disadvantages of reusing recycled materials? • What are the advantages and disadvantages of burning or burying solid waste? • What is hazardous waste and how can we deal with it?
Chapter Overview Questions (cont’d) • What can we do to reduce exposure to lead and mercury? • How can we make the transition to a more sustainable low-waste society?
Disposable? • We live in a disposable society, trash is an everyday reality for every American. • What does this term mean? • Wall-E • Think about our habits and perception of trash. • What are the factors in identifying a disposable society?
Central Case: Transforming New York’s Fresh Kills Landfill • The largest landfill in the world, it closed in 2001 • Staten Island residents viewed the landfill as an eyesore and civic blemish • It was briefly reopened to bury rubble from the World Trade Center after the September 11, 2001, attack • New York plans to transform the landfill into a world-class public park
Core Case Study: Love Canal — There Is No “Away” • Between 1842-1953, 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. • The company inserted a disclaimer denying liability for the wastes.
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 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.
Core Case Study: Love Canal — There Is No “Away” • President Jimmy Carter declared Love Canal a federal disaster area. • The area was abandoned in 1980 (left). Figure 22-1
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. • Love Canal sparked creation of the Superfund law, which forced polluters to pay for cleaning up abandoned toxic waste dumps.
Waste • Any discarded material for which no further sale or use is intended • examples: residue, chemical by-products, unused virgin material, spill absorbent material
WASTING RESOURCES • Solid waste: any unwanted or discarded material we produce that is not a liquid or gas. • Municipal solid waste (MSW): produce directly from homes. • Industrial solid waste: produced indirectly by industries that supply people with goods and services.
Solid Waste • Any garbage; refuse; sludge from a waste treatment plant or air pollution control facility; and other discarded material (including solid, liquid, semi-solid or contained gaseous material) generated from any industrial, commercial or community activities; mining or agricultural operations
Solid Waste Exclusions • Solid or dissolved materials in domestic sewage or irrigation return flows • Industrial discharges subject to CWA regulations, including POTW • Source, special nuclear or by-product material defined by the Atomic Energy Act of 1954
Ways to reduce waste that enters waste stream • Waste stream = flow of waste as it moves from its sources toward disposal destinations • More efficient use of materials, consume less, buy goods with less packaging, reusing goods • Recovery (recycling, composting) = next best strategy in waste management • Recycling = sends used goods to manufacture new goods • Composting = recovery of organic waste • All materials in nature are recycled
Patterns in the municipal solid waste stream vary • Municipal solid waste is also referred to as trash or garbage • In the U.S., paper, yard debris, food scraps, and plastics are the principal components of municipal solid waste • Even after recycling, paper is the largest component of solid waste • Most waste comes from packaging • In developing countries, food scraps are the primary contributor • Wealthy nations invest more in waste collection and disposal
What do we throw away? • Take your trash bag and sort it out. • What percentage of your sample can be recycled? • What percentage of your sample is organic waste?
How Much Trash is Generated? • Of the 251 million tons (228 million metric tons) of trash, or solid waste, generated in the United States in 2006, about 81.8 million tons (74.2 million metric tons), or 32.5 percent, was either recycled or composted [source: EPA].
Materials Discarded in a Municipal Landfill • Paper and paperboard 41.0% • Yard waste 17.9% • Glass 8.2% • Metal 8.7% • Rubber, leather, textiles 8.1% • Food waste 7.9% • Plastic 6.5% • Miscellaneous inorganic 1.6%
Electronic Waste: A Growing Problem • 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. Figure 22-4
“E-waste” is a new and growing problem • Electronic waste (“e-waste”) = waste involving electronic devices • Computers, printers, VCRs, fax machines, cell phones • Disposed of in landfills, but should be treated as hazardous waste • Some people and businesses are trying to use and reuse electronics to reduce waste
Waste generation is rising in the U.S. In the U.S,, since 1960, waste generation has increased by 2.8 times
WASTING RESOURCES • Solid wastes polluting a river in Jakarta, Indonesia. The man in the boat is looking for items to salvage or sell. Figure 22-3
“The Story of Garbage” • The Garbage Story: Dealing with Solid Waste • How much garbage and trash (municipal solid waste) do Americans produce a year? 2. Name three of the ways in which municipalities dispose of their garbage and trash. 3. Of what kind of material is most of our garbage and trash composed? 4. How is recycling helping our landfills?
Trash For Sale • The US sells it’s trash to China for recycling. • The turn in the economy has devalued the recycling industry
INTEGRATED WASTE MANAGEMENT • We can manage the solid wastes we produce and reduce or prevent their production. Figure 22-5
WASTING RESOURCES • The United States produces about a third of the world’s solid waste and buries more than half of it in landfills. • About 98.5% is industrial solid waste. • 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.
Improved disposal methods • Historically people dumped their garbage wherever it suited them • Open dumping and burning still occur throughout the world • Most industrialized nations now bury waste in lined and covered landfills or burn it in incineration facilities • In the U.S., recycling is decreasing pressure on landfills
Burying Solid Waste • Most of the world’s 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. • 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 are regulated • Sanitary landfills = waste buried in the ground or piled in large, engineered mounds • Must meet national standards set by the EPA under the Resource Conservation and Recovery Act (RCRA) of 1976 • Waste is partially decomposed by bacteria and compresses under its own weight to make more space • Layered with soil to reduce odor, speed decomposition, reduce infestation by pets • When a landfill is closed, it must be capped and maintained
40 CFR Parts 239-259 • The purpose of this part is to establish minimum national criteria under the Resource Conservation and Recovery Act (RCRA or the Act), as amended, for all municipal solid waste landfill (MSWLF) units and under the Clean Water Act, as amended, for municipal solid waste landfills that are used to dispose of sewage sludge. These minimum national criteria ensure the protection of human health and the environment.
Regulatory Guidelines • Subtitle D, of RCRA regulates non-hazardous waste • Siting • Design • Operation • Monitoring • Closure and post-closure • Financial assurance
Why do we have landfills? • Protect groundwater • Protect surface water • Protect air quality • Control pathogenic migration
Landfill Design • The main waste contaminant features are • Underlying soils • Depth to groundwater • Landfill liner (triple liner) • Leachate collection system • Leachate prevention through infiltration and drainage control • Cover soil and final landfill cap
The Size of the Landfill • Limit of Refuse filing (LRF) determines the volume of waste that can be properly stored at the site • Determined by site characterization, proximity to surface and groundwater
The Liner • A liner acts like a giant garbage bag • Clay liner • Synthetic liner • Additional liner
Drainage Control • Surface water infiltration is drained from the landfill
Leachate • Leachate is the liquid that migrates from within a land disposal site which has come in contact with solid waste.
Monitoring • Groundwater monitoring wells are installed around the landfill to monitor pollution migration. • Gas collection wells are installed to remove methane which is a natural decomposition product or organic material.
Procedures • Waste is broken down and moved into the landfill. • A layer of dirt is used to cover the waste.
Closure • Solid waste is layered with soil or clay and capped off.
When landfill is full, layers of soil and clay seal in trash Topsoil Electricity generator building Sand Clay Methane storage and compressor building Leachate treatment system Garbage Probes to detect methane leaks Pipes collect explosive methane as used as fuel to generate electricity Methane gas recovery well Leachate storage tank Compacted solid waste Groundwater monitoring well Garbage Leachate pipes 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. 22-12, p. 532