Global waste production is a critical issue in environmental quality. Global waste production is rapidly growing, as nonbiodegradable materials grow in a waste stream.
Solid waste includes domestic, commercial, industrial, agricultural, and mining wastes that are primarily nontoxic. About 60 percent of North American domestic and industrial wastes are deposited in landfills; most of the rest is incinerated or recycled. Old landfills were often leaky and messy, and they have been an important source of groundwater contamination. Modern landfills must have impermeable liners that prevent seepage to groundwater, and they must be covered with soil and monitored for gas emissions and water contamination.
Incineration is our second most important method of waste disposal. Incineration can destroy organic compounds, and it can be used to produce energy. Airborne contaminants can result from burning, however, especially if incinerators are not operated at optimal temperatures or if toxic substances are burned.
Recycling and composting (of yard waste and other organic materials) are growing in North America and globally. The growing cost of waste disposal makes collection increasingly cost-effective, and the rapid depletion of landfill space makes recycling attractive. A principal obstacle to recycling is weak or unstable markets for recycled plastic, paper, and other materials. The growing use of disposable plastic beverage containers poses another important problem to widespread recycling. Japan is a world leader in recycling, with about 60 percent of domestic waste being recycled.
Reusing, demanufacturing, and reducing material consumption are important additional strategies for reducing the waste stream.
Hazardous and toxic wastes are waste materials that cause health problems, including birth defects, neurological disorders, reduced resistance to infection, and cancer. Environmental costs of hazardous and toxic waste include contamination of water supplies, poisoning of soil, and destruction of habitat.
The major categories of hazardous wastes are ignitable, corrosive, reactive, explosive, and toxic materials. Some materials of greatest concern are heavy metals, solvents, and synthetic organic chemicals such as halogenated hydrocarbons, organophosphates, and phenoxy herbicides.
Disposal practices for solid and hazardous wastes have often been unsatisfactory. Thousands of abandoned, often unknown waste disposal sites still leak toxic materials into the environment. Techniques for controlling hazardous wastes include not making the material in the first place; incineration; secure landfills; and physical, chemical, or biological treatment to detoxify or immobilize wastes.
The Superfund is a revolving fund to finance cleanup of some of our worst hazardous waste sites. The Superfund was established by the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) of 1980. Many sites on the Superfund’s National Priority List are abandoned factories or dumps.
Dangerous wastes are often removed from wealthy countries or neighborhoods to poorer ones, and cleanup efforts may be faster and more complete in wealthier areas. Proponents of environmental justice try to identify these patterns and rectify them.
People often resist having transfer facilities, storage sites, disposal operations, or transportation of hazardous materials (often referred to as Locally Unwanted Land Uses, or LULUs) near where they live. Safe handling and liability remain unanswered in solid and hazardous waste disposal.
