Hazardous waste
Hazardous waste refers to materials that possess ignitable, corrosive, reactive, or toxic properties, posing significant risks to human health and the environment. In the United States, a small percentage of waste generators are responsible for the majority of hazardous waste production. Improper disposal of these wastes can lead to severe environmental degradation, including air and water pollution, which can adversely affect ecosystems, agriculture, and public health. Notably, substances like dioxins, PCBs, and cyanides are classified as high-risk due to their persistent and toxic nature.
To manage hazardous waste effectively, various strategies are employed, such as waste reduction, recycling, and treatment to diminish harmful effects. Regulatory frameworks, primarily established by the Environmental Protection Agency (EPA), mandate that waste generators track their hazardous waste from its creation to disposal. Significant legislation, including the Resource Conservation and Recovery Act (RCRA), has been enacted to address hazardous waste management and remediation, particularly in the context of historical dumping practices. Despite advancements in waste management technologies, challenges remain, particularly in less industrialized nations, where hazardous waste issues are often neglected, potentially leading to future environmental crises.
Subject Terms
Hazardous waste
Definition: Waste products of industrial society that pose dangers to human health and the environment
Although many national governments have taken steps to regulate the disposal of hazardous wastes, some have not, and many such wastes continue to be produced all over the world. Improper disposal of hazardous wastes creates serious problems for the environment.
In the United States, hazardous wastes are legally defined as materials that have ignitable, corrosive, reactive, or toxic properties. In the early 1990s approximately 97 percent of all hazardous waste in the United States was produced by 2 percent of the waste generators. Remediation and cleanup of these wastes involve substantial economic cost. Since the 1970s the United States and other Western democracies have tried to regulate hazardous waste disposal. Hazardous wastes are also a serious problem in the former Soviet Union and other Eastern European nations.
Environmental Problems
Improper disposal of hazardous waste can lead to the release of chemicals into the air, surface water, groundwater, and soil. High-risk wastes are those known to contain significant concentrations of constituents that are highly toxic, persistent, highly mobile, or bioaccumulative. Examples include dioxin-based wastes, polychlorinated biphenyls (PCBs), and cyanide wastes. Intermediate-risk wastes may include metal hydroxide sludges, while low-risk wastes are generally high-volume, low-hazard materials. Radioactive waste is a special category of hazardous waste, often presenting extremely high risks, as do biomedical and mining wastes.
Hazardous waste presents varying degrees of health and environmental hazards. When combined, two relatively low-risk materials may pose a high risk. Factors that affect the health risk of hazardous waste include dosage received; age, gender, and body weight of those exposed; and weather conditions. The health effects posed by hazardous waste include cancer, genetic defects, reproductive abnormalities, and central nervous system disorders.
Environmental degradation resulting from hazardous waste can render various natural resources, such as croplands and forests, useless and can harm animal life. For example, chemicals can leach out of improperly stored waste and into groundwater. Hazardous wastes may also generate long-lasting air pollution, water pollution, or soil contamination. In the past, before standards were in place for managing hazardous wastes, such materials were often buried or stored in unattended drums or other containers. This situation created threats to the environment and human health when the original containers began to leak and the materials leached into the soil and the water supply.
Methods for Handling Wastes
The technologies and methods used in dealing with hazardous solid and liquid wastes continue to evolve. Several approaches have had positive impacts on the environment and the consumption of natural resources. One is the reduction of the volume of waste material through efforts to generate less of it. Another approach is to recycle hazardous materials as much as possible. A third means of dealing with hazardous waste is to treat it to render it less harmful; often, such treatment also reduces its volume. Least desirable among methods of addressing the problem is the storage of hazardous wastes in landfills. The Environmental Protection Agency (EPA) has established standards for the responsibility and tracking of hazardous wastes, based on the principle that waste generators are responsible for their waste “from cradle to grave.” This principle requires that waste generators and disposal sites keep extensive records.
The costs for the cleanup and remediation of hazardous waste are substantial and are likely to continue to grow. This situation is particularly true in Eastern Europe and the nations of the former Soviet Union, where the magnitude of past dumping of hazardous materials is slowly becoming apparent. Meanwhile, less industrialized nations generally are ignoring the issue of hazardous waste, thereby setting themselves up for future difficulties.
US Legislation
The 1984 amendments to the federal Resource Conservation and Recovery Act (RCRA) included a thorough overhaul of hazardous waste legislation. Previously exempt sources that generated between 100 and 1,000 kilograms (220 and 2,200 pounds) of hazardous waste per month were brought under RCRA provisions. Congress further tried to force the EPA to adopt a bias against the landfilling of hazardous waste with a “no land disposal unless proven safe” provision. The amendments also added underground storage tanks for gasoline, petroleum, pesticides, and solvents to the list of sources to be regulated and remediated. In addition to RCRA, the Comprehensive Environmental Response, Compensation, and Liability Act of 1980 (known as Superfund) provides for the cleanup of all categories of abandoned hazardous waste sites except for radioactive waste sites. Several other statutes (and ensuing EPA regulations) have dealt with these aspects of the hazardous waste problem. The cleanup of existing sites will continue to be a troubling problem, while the cleanup and disposal of radioactive waste will be a major issue for the future.
The waste-minimization philosophy expressed in RCRA is a sound long-range strategy for dealing with hazardous waste. However, some materials will continue to be deposited in landfills. Incineration offers one solution to the problem of volume of material but poses issues of air quality and disposal of the highly toxic ash remaining. As some firms have found, minimizing their waste stream affords them economic benefits while conserving natural resources.
Household waste, which is not regulated by RCRA, often includes small quantities of hazardous materials such as pesticides. Many of these materials are still being landfilled in the early twenty-first century, as individual consumers remain ignorant of the proper ways to dispose of such wastes.
Bibliography
Fletcher, Thomas H. From Love Canal to Environmental Justice: The Politics of Hazardous Waste on the Canada-U.S. Border. Orchard Park, N.Y.: Broadview Press, 2003.
Grisham, Joe. Health Aspects of the Disposal of Waste Chemicals. New York: Pergamon, 1986.
Hill, Marquita K. “Hazardous Waste.” In Understanding Environmental Pollution. 3d ed. New York: Cambridge University Press, 2010.
LaGrega, Michael D., Philip L. Buckingham, and Jeffrey C. Evans. Hazardous Waste Management. 2d ed. New York: McGraw-Hill, 2001.
McKinney, Michael L., Robert M. Schoch, and Logan Yonavjak. “Municipal Solid Waste and Hazardous Waste.” In Environmental Science: Systems and Solutions. 4th ed. Sudbury, Mass.: Jones and Bartlett, 2007.