Toxic And Radioactive Waste

Toxic and radioactive waste are even more problematic than conventional waste for obvious reasons (Cohen, 1984; Davis & Lester, 1988; Lave & Upton, 1987). Toxic waste is generated by a variety of industrial processes; some also comes from solvents and chemicals used in the home. Chlorinated solvents widely used to remove oil from clothes or machinery are among the most common contaminants of ground water at toxic waste sites (National Research Council, 1994). According to one EPA estimate, there are about 30,000 toxic chemical waste disposal sites in the United States, and the number is increasing (Upton, Kneip, & Toniolo, 1989).

The U.S. government has recognized the problem and enacted legislation—most notably, the Comprehensive Environmental Response, Compensation, and Liability Act of 1980 (as reauthorized and amended in 1986)—to address it. Generally known as Superfund, the legislation mandates the cleanup of problem sites. Cleanup is expensive, however, and progress has been slow; only a small fraction of the sites included on a National Priority List compiled by the EPA have been completely cleaned up. Moreover, the full extent of the problem of toxic waste is not known. Gute ( 1991) gave 67,000 as the approximate number of chemicals in use in the U.S. commercial market, on only about 30% of which any human health effects data exist, and for only about 2% of which the data that exist suffice to quantify human health effects.

The problem of toxic waste disposal is especially severe in parts of Eastern Europe. Since the unification of Germany, for example, it has been estimated that there are at least tens of thousands of potentially toxic dump sites in largely unidentified locations in the old eastern zone (Cezeaux, 1991).

A major contributor to the problem of toxic waste that has attracted some attention in recent years is medicine. According to Hershkowitz ( 1990), there are about 6,000 substandard medical-waste incinerators at hospitals in the United States emitting toxins—including dioxin, heavy metals, and acid gases—into the air often in populous areas.

Mercury, which is found in thermometers, thermostats, barometers, flourescent lights, and gauges of various sorts, as well as in dental amalgam used for tooth fillings, represents a health hazard as waste because it is transformed by bacteria into methylmercury, a neurotoxin, that can accumulate in the food chain and contaminate fish consumed by humans. Mercury can enter the atmosphere by the burning of fossil fuels or the incineration of municipal or medical waste, and it finds its way to water when it falls during precipitation.

High-level nuclear waste (waste with a high concentration of radioactive elements with a relatively long half-life) exists in the United States both as spent nuclear reactor fuel rods and as the acid in which fuel rods have been dissolved in the production of plutonium. As of 1998, the amount of spent fuel stored at U.S. nuclear power plants exceeded 30,000 metric tons and was growing by more than 2,000 metric tons per year. Projections had the total amount of such waste reaching 75 metric tons by 2020 (Hollister & Nadis, 1998).

Most of the spent fuel (still highly radioactive) is stored in cooling ponds near the reactors that produced it, but such storage is intended to be temporary. Finding long-term repositories for this material remains a problem about which controversy continues. Radioactive liquid waste is stored in steel tanks at the Hanford Military Reservation in the state of Washington and at the Savannah River plant in South Carolina. Significant amounts of radioactive material are believed to have been released to the ground, water, and air (Shulman, 1989). The cost of cleanup of radioactive leakage from U.S. military weapons facilities has been projected to be about $130 billion over the next few decades (National Academy of Sciences, 1989). The question of how and where to store high-level radioactive waste for the long term promises to be a matter of intense debate for some time to come (Hollister & Nadis, 1998; Whipple, 1996).

Low-level radioactive waste disposal also constitutes a major unsolved problem. Much of this waste comes from the use of radioactive materials in medicine and in biotechnological research and development. Experts disagree on what represents safe storage of such waste and about the nature and magnitude of risks associated with specific proposals (Cohen, 1994). A Science editorial by Philip Abelson (1995a) regarding a specific proposed repository for low-level radioactive waste, a sample of the letters it evoked (Althuis, 1995; Budin, 1995; Grossman, 1995; Warf, 1995; Wilshire, 1995), and Abelson's (1995b) rejoinder illustrate the point.

Radioactive waste disposal is bound to become increasingly problematic in the near future because about 50 nuclear power plants in the Western world are, or soon will be, ready for decommissioning and dismantling—about 12 U.S.

reactors were ready for retirement as of 1989 (Shulman, 1989). The problems of selecting long-term storage sites and transporting radioactive waste to them have proved controversial among the general public. In view of the lack of agreement among experts on how best to manage radioactive waste, it is perhaps not surprising that the public has shown considerable distrust of the efforts of government and industry in this regard (Binney, Mason, Martsolf, & Detweiler, 1996; Greenberg, Lowrie, Krueckeberg, Mayer, & Simon, 1997; Slovic, 1993) and has persisted with nearly uniformly negative attitudes toward nuclear waste that are influenced very little by opinions of those technical experts who argue that safe disposal is feasible with current storage techniques (Slovic, Flynn, & Layman, 1991). Safety is a major concern, but not the only one; the prospect of siting a hazardous waste facility in one's community can also evoke strong resistance because of the actual or anticipated effect on property values or the quality or status of the community (Greenberg & Schneider, 1994, 1996; Greenberg, Schneider, & Choi, 1994).

Efforts to deal with the problem of hazardous waste have been of three types: (a) cleanup or remediation of existing hazardous waste repository sites, (b) reduction of the amount of hazardous waste produced, and (c) identification of new and safer ways of disposing of or managing hazardous waste (Portney, 1991b). The cost, complexity, and uncertain effectiveness of cleanup operations make the case for the importance of both reducing the amount of hazardous waste produced and finding more effective ways of disposing of or managing what is produced.

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