Manhan, Stanley E. "NATURE, SOURCES, AND ENVIRONMENTAL CHEMISTRY OF HAZARDOUS WASTES" Fundamentals of Environmental Chemistry Boca raton: LLC, CRC press, 2001 21 NATURE, SOURCES, AND ENVIRONMENTAL CHEMISTRY OF HAZARDOUS WASTES __________________________ 21.1 INTRODUCTION A hazardous substance is a material that may pose a danger to living organisms, materials, structures, or the environment by explosion or fire hazards, corrosion, toxicity to organisms, or other detrimental effects. What, then, is a hazardous waste? Although it has has been stated that,1 “The discussion on this question is as long as it is fruitless,” a simple definition of a hazardous waste is that it is a hazardous substance that has been discarded, abandoned, neglected, released or designated as a waste material, or one that might interact with other substances to be hazardous. The definition of hazardous waste is addressed in greater detail in Section 21.2, but, in a simple sense, it is a material that has been left where it should not be and that could cause harm to living creatures or its surroundings. History of Hazardous Substances Humans have always been exposed to hazardous substances, going back to prehistoric times when people inhaled noxious volcanic gases or succumbed to carbon monoxide from inadequately vented fires in cave dwellings sealed too well against Ice-Age cold. Slaves in Ancient Greece developed lung disease from weaving mineral asbestos fibers into cloth to make it more degradation-resistant. Some archaeological and historical studies have concluded that lead wine containers were a leading cause of lead poisoning in the more affluent ruling class of the Roman Empire, leading to erratic behavior such as fixation on spectacular sporting events, chronic unmanageable budget deficits, speculative purchases of overvalued stock, illicit trysts in governmental offices, and ill-conceived, overly ambitious military ventures in remote foreign lands. Alchemists who worked during the Middle Ages often suffered debilitating injuries and illnesses resulting from the hazards of their explosive and toxic chemicals. During the 1700s, runoff from mine-spoils piles © 2001 CRC Press LLC began to create serious contamination problems in Europe. As the production of dyes and other organic chemicals developed from the coal tar industry in Germany during the 1800s, pollution and poisoning from coal tar byproducts was observed. By around 1900 the quantity and variety of chemical wastes produced each year was increasing sharply with the addition of wastes such as spent steel and iron pickling liquor, lead battery wastes, chromic wastes, petroleum refinery wastes, radium wastes, and fluoride wastes from aluminum ore refining. As the century progressed into the World War II era, the wastes and hazardous byproducts of manufacturing increased markedly from sources such as chlorinated solvent manufacture, pesticide synthesis, polymer manufacture, plastics, paints, and wood preservatives. The Love Canal affair of the 1970s and 1980s brought hazardous wastes to public attention as a major political issue in the U.S. Starting around 1940, this site in Niagara Falls, New York, had received about 20,000 metric tons of chemical wastes containing at least 80 different chemicals. By 1994, state and federal governments had spent well over $100 million to clean up the site and relocate residents. Other areas containing hazardous wastes that received attention included an industrial site in Woburn, Massachusetts, that had been contaminated by wastes from tanneries, glue-making factories, and chemical companies dating back to about 1850; the Stringfellow Acid Pits near Riverside, California; the Valley of the Drums in Kentucky; and Times Beach, Missouri, an entire town that was abandoned because of contamination by TCDD (dioxin). The problem of hazardous wastes is truly international in scope.2 As the result of the problem of dumping such wastes in developing countries, the 1989 Basel Convention on the Control of Transboundary Movement of Hazardous Wastes and their Disposal was held in Basel, Switzerland in 1989, and by 1998 had been signed by more than 100 countries. This treaty defines a long List A of hazardous wastes, a List B of nonhazardous wastes, and a List C of as yet unclassified materials. An example of a material on List C is polyvinyl chloride (PVC) coated wire, which is harmless itself, but may release dioxins or heavy metals when thermally treated. Legislation Governments in a number of nations have passed legislation to deal with hazardous substances and wastes. In the U.S., such legislation has included the following: • Toxic Substances Control Act of 1976 • Resource Conservation and Recovery Act (RCRA) of 1976 (amended and reauthorized by the Hazardous and Solid Wastes Amendments Act (HSWA) of 1984) • Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) of 1980 RCRA legislation charged the U.S. Environmental Protection Agency (EPA) with protecting human health and the environment from improper management and © 2001 CRC Press LLC disposal of hazardous wastes by issuing and enforcing regulations pertaining to such wastes. RCRA requires that hazardous wastes and their characteristics be listed and controlled from the time of their origin until their proper disposal or destruction. Regulations pertaining to firms generating and transporting hazardous wastes require that they keep detailed records, including reports on their activities and manifests to ensure proper tracking of hazardous wastes through transportation systems. Approved containers and labels must be used, and wastes can only be delivered to facilities approved for treatment, storage, and disposal. There are about 290 million tons of wastes regulated by RCRA. In the U.S., about 3,000 facilities are involved in the treatment, storage, or disposal of RCRA wastes. CERCLA (Superfund) legislation deals with actual or potential releases of hazardous materials that have the potential to endanger people or the surrounding environment at uncontrolled or abandoned hazardous-waste sites in the U.S. The act requires responsible parties or the government to clean up waste sites. Among CERCLA’s major purposes are the following: • Site identification • Evaluation of danger from waste sites • Evaluation of damages to natural resources • Monitoring of release of hazardous substances from sites • Removal or cleanup of wastes by responsible parties or government CERCLA was extended for 5 years by the passage of the Superfund Amendments and Reauthorization Act (SARA) of 1986, legislation with greatly increased scope and additonal in funding. Actually longer than CERCLA, SARA encouraged the development of alternatives to land disposal that favor permanent solutions reducing volume, mobility, and toxicity of wastes; increased emphasis upon public health, research, training, and state and citizen involvement; and estab- lishment of a new program for leaking underground (petroleum) storage tanks. After 1986 few new legislative initiatives dealing with hazardous wastes were forthcoming in the U.S. As of 1999, the U.S. Congress had gone for six years without reauthorizing Superfund. During 1999, both the House and Senate were considering passage of legislation to reauthorize the Superfund act in an amended form.3 As of 1998, there were 1,359 designated Superfund sites, of which 509 sites, 37 percent of the total, had been cleaned up at a total cost to companies of $15 billion.4 Assuming the same cost for each of the remaining sites, an additional $25 billion in private-sector funds would be required to clean them up. The DuPont company, for example, listed an accrued liability of $561 million for waste-site cleanup on its 1997 annual report, down from $602 million in 1995. 21.2 CLASSIFICATION OF HAZARDOUS SUBSTANCES AND WASTES Many specific chemicals in widespread use are hazardous because of their chemical reactivities, fire hazards, toxicities, and other properties. There are © 2001 CRC Press LLC numerous kinds of hazardous substances, usually consisting of mixtures of specific chemicals. These include such things as explosives; flammable liquids; flammable solids, such as magnesium metal and sodium hydride; oxidizing materials such as peroxides; corrosive materials, such as strong acids; etiologic agents that cause disease; and radioactive materials. Characteristics and Listed Wastes For regulatory and legal purposes in the U.S., hazardous substances are listed specifically and are defined according to general characteristics. Under the authority of the Resource Conservation and Recovery Act (RCRA), the United States Environmental Protection Agency (EPA) defines hazardous substances in terms of the following characteristics: • Ignitability, characteristic of substances that are liquids, the vapors of which are likely to ignite in the presence of ignition sources; nonliquids that may catch fire from friction or contact with water and that burn vigorously or persistently; ignitable compressed gases; and oxidizers • Corrosivity, characteristic of substances that exhibit extremes of acidity or basicity or a tendency to corrode steel • Reactivity, characteristic of substances that have a tendency to undergo violent chemical change (examples are explosives, pyrophoric materials, water-reactive substances, or cyanide- or sulfide-bearing wastes) • Toxicity, defined in terms of a standard extraction procedure followed by chemical analysis for specific substances In addition to classification by characteristics,