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 Since it is usually not stated which quantity is used, it is better to write the unit as kg/kg, mol/mol or m/m (even though they are all dimensionless). The difference is quite significant when dealing with gases and it is very important to specify which quantity is being used. For example, the conversion factor between a mass fraction of 1 ppb and a mole fraction of 1 ppb is about 4.7 for the greenhouse gas CFC-11 in air. For volume fraction, the suffix "V" or "v" is sometimes appended to the parts-per notation (e.g., ppmV, ppbv, pptv). Unfortunately, ppbv and