7.1 Systems of waste management  (Page 4/43)

Radioactive waste regulations

Although non-hazardous waste (MSW and industrial non-hazardous waste) and hazardous waste are regulated by RCRA, nuclear or radioactive waste is regulated in accordance with the Atomic Energy Act of 1954 by the Nuclear Regulatory Commission (NRC) in the United States.

Radioactive wastes are characterized according to four categories: (1) High-level waste (HLW), (2) Transuranic waste (TRU), (3) Low-level waste (LLW), and (4) Mill tailings . Various radioactive wastes decay at different rates, but health and environmental dangers due to radiation may persist for hundreds or thousands of years.

HLW is typically liquid or solid waste that results from government defense related activities or from nuclear power plants and spent fuel assemblies. These wastes are extremely dangerous due to their heavy concentrations of radionuclides, and humans must not come into contact with them.

TRU mainly results from the reprocessing of spent nuclear fuels and from the fabrication of nuclear weapons for defense projects. They are characterized by moderately penetrating radiation and a decay time of approximately twenty years until safe radionuclide levels are achieved. Following the passage of a reprocessing ban in 1977, most of this waste generation ended. Even though the ban was lifted in 1981, TRU continues to be rare because reprocessing of nuclear fuel is expensive. Further, because the extracted plutonium may be used to manufacture nuclear weapons, political and social pressures minimize these activities.

LLW wastes include much of the remainder of radioactive waste materials. They constitute over 80 percent of the volume of all nuclear wastes, but only about two percent of total radioactivity. Sources of LLW include all of the previously cited sources of HLW and TRU, plus wastes generated by hospitals, industrial plants, universities, and commercial laboratories. LLW is much less dangerous than HLW, and NRC regulations allow some very low-level wastes to be released to the environment. LLW may also be stored or buried until the isotopes decay to levels low enough such that it may be disposed of as non-hazardous waste. LLW disposal is managed at the state level, but requirements for operation and disposal are established by the USEPA and NRC. The Occupational Health and Safety Administration (OSHA) is the agency in charge of setting the standards for workers that are exposed to radioactive materials.

Mill tailings generally consist of residues from the mining and extraction of uranium from its ore. There are more than 200 million tons of radioactive mill-tailings in the United States, and all of it is stored in sparsely populated areas within the western states, such as Arizona, New Mexico, Utah, and Wyoming. These wastes emit low-level radiation, and much of it is buried to reduce dangerous emissions.

Medical waste regulations

Another type of waste that is of environmental concern is medical waste    . Medical waste is regulated by several federal agencies, including the USEPA, OSHA, the Center for Disease Control and Prevention (CDC) of the U.S. Department of Health and Human Services, and the Agency for Toxic Substances and Disease Registry (ATSDR) of the Public Health Service, U.S. Department of Health and Human Services . During 1987-88, medical wastes and raw garbage washed up on beaches along the New Jersey Shore of the United States on several occasions (called, " Syringe Tide ") which required closure of beaches. The U.S. Congress subsequently enacted the Medical Waste Tracking Act (MWTA) to evaluate management issues and potential risks related to medical waste disposal. The seven types of wastes listed under MWTA include: (1) microbiological wastes (cultures and stocks of infectious wastes and associated biological media that can cause disease in humans); (2) human blood and blood products, including serum, plasma, and other blood components; (3) pathological wastes of human origin, including tissues, organs, and other body masses removed during surgeries or autopsies); (4) contaminated animal wastes (i.e. animal carcasses, body masses, and bedding exposed to infectious agents during medical research, pharmaceutical testing, or production of biological media); (5) isolation wastes (wastes associated with animals or humans known to be infected with highly communicable diseases); (6) contaminated sharps (including hypodermic needles, scalpels, and broken glass); and (7) uncontaminated sharps. In addition, the USEPA considered including any other wastes that had been in contact with infectious agents or blood (e.g. sponges, soiled dressings, drapes, surgical gloves, laboratory coats, slides).