Hazardous wastes are those that can cause irreversible damage or severe damage and may include acids, strong bases, radioactive materials, harmful chemicals, carcinogens, etc. The method of disposal depends on the type of hazardous waste. Some of the hazardous wastes such as strong acids and bases can be neutralized using bases and acids, respectively. Some of the hazardous wastes can be recycled and reused. Many of the hazardous wastes are disposed off in landfill sites and provided permanent cover, leachate and gas collection system. This is done to prevent physical contact with these wastes and collection and treatment of their harmful by-products. Severe hazardous waste like uranium (from nuclear plants) is stored at site until a permanent repository is constructed (Yucca Mountain site, originally planned underground repository, has been shelved).
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