Hazardous waste threatens human health or the environment if it is carelessly thrown away, dumped into the ground or handled improperly. According to the EPA, solid waste or municipal solid waste (MSW) is commonly known as trash or garbage. It refers to the overall garbage created by a community, including household waste, as well as the waste generated by businesses, schools and institutions.
Types of Waste
A hazardous waste may be in solid, semi-solid, liquid or gaseous form. According to the EPA, the hazardous waste can be classified into listed wastes (source-specific wastes, non-specific source wastes and unused chemical products), characteristic wastes (toxic wastes, ignitable wastes, reactive wastes and corrosive wastes) universal wastes (batteries, pesticides, mercury-containing equipment and bulbs) and mixed wastes.
Municipal solid waste consists of paper, yard waste, metals, food, glass, wood, plastic and miscellaneous materials.
Solid waste generation is escalating with the increasing population. Disposal of solid waste in landfills is detrimental to the environment, as it can pollute the surrounding air and water. Toxic gases such as methane and carbon dioxide are formed when the waste in landfills decomposes. People living near landfills are susceptible to lung cancer, bladder cancer and leukemia. Incineration of solid waste releases toxic air pollutants, such as dioxins, which are carcinogenic and may cause birth defects.
Nuclear waste is hazardous and can remain radioactive for long periods of time, thereby affecting the environment and human health. Improper hazardous waste disposal from industries causes health problems in nearby communities. The presence of cancer-causing metal arsenic and toxic metal toluene may cause memory loss, hearing loss and various other conditions.
Disposal options for hazardous waste are landfills, incineration, land treatment units and injection wells. Other alternatives include recycling and reducing the use of hazardous waste.
Landfill is the most prevalent disposal option for solid waste. In addition, solid waste is also burned at extremely high temperatures to reduce the waste volume. Alternative techniques of disposing solid waste include recycling and composting.
Hazardous waste containing metal particles and ash are sent to metal recovery facilities where metal can be recovered from them. According to Science Daily, a new technology involves the recovery of uranium from the ashes of radioactive garbage to be recycled back into nuclear fuel.
Recycling solid waste materials such as paper, plastic, glass, metal and rubber, transforms the old products into new ones by mechanical or chemical methods. Heat is generated during incineration of solid waste, which could be used to heat water. The steam thus produced could be used to drive turbines to generate electricity.
The EPA has clear regulations on how to dispose hazardous and solid wastes.
Special precautions need to be taken to dispose hazardous waste both in solid and liquid forms. EPA mandates the combustion or incineration of hazardous waste when possible. For waste in liquid form, underground injection wells should be used.
For solid waste disposal, EPA has guidelines on how to design landfills, where to locate them and how to maintain them.