Chapter 24 Solid and Hazardous Wastes

Overview of Chapter 24 Solid Waste Waste Prevention Hazardous Waste Reducing the Amount of Waste Reusing Products Recycling Materials Hazardous Waste Types of Hazardous Waste Management of Hazardous Waste

Solid Waste US generates more solid waste per capita than any other country 2.1 kg per person per day

Types of Solid Waste Municipal solid waste Non-municipal solid waste Solid material discarded by homes, office buildings, retail stores, schools, etc. Relatively small portion of solid waste produced Non-municipal solid waste Solid waste generated by industry, agriculture, and mining

Composition of Municipal Solid Waste

Disposal of Solid Waste Three methods Sanitary Landfills Incineration Recycling

Sanitary Landfill

Sanitary Landfill Compacting and burying waste under a shallow layer of soil Most common method of disposal Problems Methane gas production by microorganisms Contamination of surface water & ground water by leachate Not a long-term remedy Few new facilities being opened Closing a full landfill is very expensive

Sanitary Landfill Special Problem: Plastic Special Problem: Tires Much of plastic is from packaging Chemically stable and do not readily break down and decompose Special Problem: Tires Made from materials that cannot be recycled Can be incinerated or shredded

Incineration Volume of solid waste reduced by 90% Produces heat that can make steam to generate electricity Produce less carbon emissions than fossil fuel power plants Byproduct Bottom ash Fly ash

Incineration Types of Incinerators Mass burn (below) Modular Refuse-derived

Composting Municipal Solid Waste Composting Includes: Food scraps, Sewage sludge, Agricultural manure, Yard waste Reduces yard waste in landfills Can be sold or distributed to community

Waste Prevention Three Goals (1) Reduce the amount of waste (2) Reuse products (3) Recycle materials

Reducing Waste Purchase products with less packaging

Reducing Waste Source reduction Pollution Prevention Act (1990) Products designed and manufactured to decrease the volume of solid waste Pollution Prevention Act (1990) Dematerialization Progressive decrease in the size and weight of a product as a result of technological improvements

Reusing Products Refilling glass beverage bottles Heavier glass that costs more Japan recycles almost all bottles Reused 20 times

Recycling Materials Every ton of recycled paper saves: Recycle 17 trees 7000 gallons of water 4100 kwatt-hrs of energy 3 cubic yards of landfill space Recycle Glass bottles, newspapers, steel cans, plastic bottles, cardboard, office paper

Recycling Recycling Paper Recycling Glass US recycles 50% Many developed countries are higher Recycling Glass US recycles 25% Costs less than new glass (right)

Recycling Recycling Aluminum Recycling Metals other than Aluminum Making new can from recycled one costs far less than making a brand new one 49% of aluminum was recycled in 2007 Recycling Metals other than Aluminum Lead, gold, iron, steel, silver and zinc Metallic composition is often unknown Makes recycling difficult

Recycling Recycling Plastic 12% of all plastic was recycled in 2007 Less expensive to make from raw materials 37% of PET was recycled in 2007 Mostly water and soda bottles

Recycling Recycling Tires Few products are made from old tires Playground equipment Trashcans Garden hose Carpet Roofing materials 36% of tires are currently recycled to make other products

Integrated Waste Management

Love Canal Toxic Waste Site Hazardous Waste Any discarded chemical that threatens human health or the environment Reactive, corrosive, explosive or toxic chemicals Types of Hazardous Waste Dioxins PCBs Radioactive waste Love Canal Toxic Waste Site

Hazardous Waste

Case-In-Point Hanford Nuclear Reservation

Management of Hazardous Waste Chemical accidents National Response Center notified Typically involves oil, gasoline or other petroleum spill Current Management Policies Resource Conservation and Recovery Act (1976, 1984) Comprehensive Environmental Response, Compensation, and Liability Act (1980) Commonly known as Superfund

Superfund Program Cleaning up existing hazardous waste: 400,000 waste sites Leaking chemical storage tanks and drums (right) Pesticides dumps Piles of mining wastes Must be cleaned up

Management of Hazardous Waste Superfund National Priorities List 2009: 1,264 sites on the list States with the greatest number of sites New Jersey (114) California (94) Pennsylvania (94) New York (85) Michigan (65)

Management of Hazardous Waste Biological Treatment of Hazardous Chemicals Bioremediation - use of bacteria and other microorganisms to break down hazardous waste into relatively harmless products Time consuming Phytoremediation - use of plants to absorb and accumulate hazardous materials in the soil Ex: Indian mustard removed heavy metals

Examples of Phytoremediation

Management of Hazardous Waste (1) Source reduction (2) Conversion to less hazardous materials (3) Long-term storage

Hazardous Waste Landfill