Since its establishment in 1970, the Illinois EPA has overseen the development and operation of a productive system of modern sanitary landfills. The Agency sees to it that these facilities meet the strictest disposal standards in history, and that they are engineered to be fully protective of human health and the environment, especially where it concerns any possibility of groundwater contamination. This is the Agency's 13th annual report on landfill disposal and available landfill capacity in Illinois. The number of active landfills in Illinois accepting waste in 1999 decreased from 58 to 53, but their total capacity soared to an all-time high during that year. Sufficient capacity exists to handle the state's requirements for landfill disposal of nonhazardous solid waste for the next 16 years, ensuring there should be no landfill capacity crisis in Illinois for the foreseeable future.