Solid waste policy in the United States produce large amounts of waste in small areas. For example, EPA reports that a single dairy cow produces approximately 120 pounds of wet manure per day equaling to that of 20-40 people. The main problems of animal waste mismanagement are environmental, especially water pollution. Industrial waste consists of a significant amount of solid waste. EPA reported that each year United States industrial facilities generate and dispose of approximately 7.6 billion tons of industrial solid waste based on 1980s figures. This figure includes waste generated from 17 industrial manufacturers of organic chemicals, inorganic chemicals, iron and steel, plastics and resins, stone,
Parts-per notation µg/m is roughly equivalent to parts-per-trillion whereas in air, it is roughly equivalent to parts-per-billion. Note also, that in the case of air, this convention is much less accurate. Whereas one liter of water is almost exactly 1 kg, one cubic meter of air is often taken as 1.143 kg—much less accurate, but still close enough for many practical uses. Parts-per notation In science and engineering, the parts-per notation is a set of pseudo-units to describe small values of miscellaneous dimensionless quantities, e.g. mole fraction or mass fraction. Since these fractions are quantity-per-quantity measures, they are pure numbers with no