Wastes are materials, which no longer serve their original purpose, are no longer useful, and are intended to be discarded. However, some materials are classified as wastes even though they may have a purpose, such as being reclaimed, recycled, or used for something other than their originally intended purpose. An example of such is hazardous/special wastes, which are used as fuels in cement kilns. These materials may be shipped as wastes, but are utilized in the cement making process.
The United States Environmental Protection Agency (EPA) regulates wastes under the Resource Conservation and Recovery Act (RCRA). By definition, a solid waste is any discarded material not excluded as stated in 40 CFR 261.2. Solid wastes, therefore, include wastes not only solid in physical state, but also liquids, semi-solids, solids with liquids, and even gaseous wastes. The term solid waste has many subdivisions, but in terms generally used when discussing waste disposal; the majority of all solid wastes can be subdivided into five (5) major classifications and several sub-classifications as listed in the chart above (note – radioactive wastes are not included in this discussion and other waste materials may be exempted from regulation under RCRA).
Municipal Solid Wastes (MSW)
MSW are also commonly referred to as trash or garbage. MSW is not required to receive pre-approval for disposal at landfills. However, sometimes a plant or business may wish to manifest or profile their MSW wastes for tracking purposes.
Construction and Demolition (C&D)
C&D wastes are debris generated during the construction, renovation, and demolition of buildings, roads and bridges. It is usually not required to receive pre-approval for disposal of C&D wastes at landfills; however oftentimes C&D waste are profiled or manifested for tracking purposes.
Special Wastes are non-hazardous waste regulated under Subtitle D of the RCRA regulations. These waste are generated from industrial processes or are wastes, which could cause unknown risks to health and the environment. Special wastes must be approved by the disposal facility before acceptance for disposal and must only be disposed of at Subtitle D permitted facilities. All special wastes must be accompanied by a manifest, a Bill of Laden, or other proper shipping papers identifying the type of wastes and profile number when they are shipped to the disposal facility.
Hazardous wastes have properties making them dangerous or potentially harmful to human health and the environment and are regulated under the Resource Conservation and Recovery Act (RCRA) Subtitle C regulations. Disposal facilities, by permit, are not allowed to accept hazardous wastes for disposal unless the waste has a current profile and is properly manifested on a Uniform Hazardous Waste Manifest (in the US). Only facilities permitted under the Subtitle C regulations are allowed to accept hazardous wastes for disposal.
Medical Wastes are waste materials generated at health care facilities such as hospitals, clinics, physician’s offices, dental practices, blood banks, and veterinary hospitals/clinics, as well as medical research facilities and laboratories. Medical waste is defined as any solid waste generated in the diagnosis, treatment, or immunization of human beings or animals, in research pertaining thereto, or in the production or testing of biological. Special regulations and facilities must be followed and utilized for the collection, transportation, and disposal of medical wastes.