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.
The Dunes: The sand dunes in great sand dunes national park are made of sand. The sand consists of these rocks and minerals: The sand in the San Juan Mountains has very small, smooth, and fine grains, while sand in the Sangre de Cristo Mountains is more coarse-grained.