492. UNIT FOUR ENVIRONMENTAL HEALTH AND SAFETY the soil, or can be fed to animals or otherwise used as energy Farms have long been known for recycling their own nonhuman solid waste Unlike agricultural waste, mining waste does not decompose in any reasonable period of time nor can it be reused in any other manner. As the extraction of the earth's natural resources intensifies, mining wastes will constitute even greater problems. Mining waste makes 12% up about 39% of the total amount of solid waste gener 3.1% ated by humans The solid waste resulting from industrial production 64% is quite varied and constitutes 6.4% of the total Examples include paper, wood chips, and highly com lex chemicals. Certain industrial waste products are especially hazardous because of their toxicity, corrosive ness, or flammability. Agriculture Municipal Household or municipal waste makes up just over Industrial 3% of all solid waste generated each year. It includes wastes generated by individual households, busi nesses FIGURE 15. 4 and institutions located within municipalities. This Sources of solid waste waste is known as municipal waste. While it makes up Source: McKinney, M. L, and R. M. Schoch(1998) nly 3. 1% of unicipal solid waste Environmental Science: Systems and Solutions. Web receives considerable attention because it is visible mal- enhanced edition. Sudbury, MA: Jones and Bartlett dorous, and considered a threat to human health if not sposed of properly The heterogeneous makeup of municipal solid waste precludes efficient dis- osal. There are seven major categories: paper, yard waste, rubber, textiles and wood,metal, glass, plastic, and food wastes(see Figure 15.5). Forty years ago food businesss. und wastes were the primary component in municipal solid waste, but garbage dis- unicipolitis posals in homes and the preprocessing of foods have reduced that greatly. Today, institutions located PGpm①3% the total. mud由书pk吗me the burning of coal. Solid Waste Management lid waste Strictly defined, solid waste management is the collection, transportation, and disposal of solid waste. a broader definition of solid waste management also includes source-reduction efforts that limit the production of solid waste in the disposal of solid waste first place. Though the preponderance of solid waste is created by agriculture and mining, the following discussion of solid waste management is aimed primarily at municipal and industrial wastes, which create greater problems in the environ mental system Collection The handling of municipal solid waste can be divided into two steps: collection and disposal. Approximately 80% of the money spent on waste management is spent on the collection process. Faced with ever-increasing amounts of waste