+ Waste Management Obj- Discuss sources and types of waste.

+ Waste Disposal Solid waste disposal is a problem in this country It is considered by some to be the most pressing environmental problem

+ Solid Waste Sources Solid waste: non-liquid, non-soluble materials 1. Industrial solid waste Primarily spoilage from mining (largest producer), logging, and other industrial processes 2. Municipal solid waste (MSW) Less quantity than industrial waste, but larger problem Amount generated doubled between Paper is the largest amount USA generates more than any country

+ Types of Solid Waste Hazardous: waste, that if there is enough, poses a threat to human life, human health, or the environment Radioactive: waste that is contaminated with any radioactive material Non-hazardous: all other wastes not meeting the definitions of hazardous or radioactive

+ Waste & Society As the population increases, the role of waste management becomes more critical Industries and municipalities must continue to develop safe and effective ways of waste disposal

+ Objective- Evaluate methods of waste management & disposal Waste Management & Disposal

+ Disposal of Solid Waste Traditionally, waste was buried in a pit or just left in the open Studies have shown that this was not an acceptable solution When water percolates through the waste, it picks up contamination As water passes through, it becomes what is called leachate, which can flow out of the waste and into streams or into the groundwater A landfill is an open area into which garbage is placed and is covered with some other material usually soil

+ Landfill Design Designed to hold waste material in a covered area, allow natural percolation or precipitation to pass through the waste and flow through the underlying soil & rocks Concept=leachate will be attenuated (neutralized by soil microorganisms and soil particles) Safe for paper products and yard waste Attenuation works by 6 natural mechanisms: adsorption, biological removal, ion exchange, dilution, filtration, chemical precipitation Natural Attenuation

+ Landfill Design Designed to minimize seepage of leachate into the surrounding soil and groundwater Most containment landfills minimize leachate, but there is still some leachate A total containment landfill is used for hazardous waste and allows no seepage Generally, containment landfills have a liner to restrict water from percolating in a natural way Often, collection pipes are used to capture and drain the seepage before it reaches the liner. This leachate is then collected and treated in a wastewater treatment plant. Best way to handle the majority of MSW More expensive to build Containment Landfill

+ Recycling of Waste Argument: Recycling reduces the need for expensive landfills Natural resources are not really benefited in any substantial way by recycling. There is no real shortage of energy sources or trees for paper The cost of solid waste disposal is the primary reason for recycling