Chlorofluorocarbons or CFCs are a chemical compound containing carbon, chlorine, and fluorine. Throughout the 20th century, CFCs were mass produced for their popularity in refrigeration and spray cans. In the 1970s, evidence began to show the harmful effects of CFCs on Earth.
Originally created as Great Sand Dunes National Monument on March 17, 1932, Great Sand Dunes National Park and Preserve was established by an act of the United States Congress on September 13, 2004.
Great Sand Dunes National Park and Preserve is a national park that conserves an area of large sand dunes up to 750 feet (229 m) tall on the eastern edge of the San Luis Valley, and an adjacent national preserve located in the Sangre de Cristo Range, in south-central Colorado, United States.