Complex sentence: The Pueblo Chemical Agent-Destruction Pilot Plant, or PCAPP, is being built to safely destroy the chemical weapons stockpile at the Pueblo Chemical Depot, located in southeastern Colorado.
Split into simpler sentences: The Pueblo Chemical Agent-Destruction Pilot Plant (PCAPP) is a chemical weapons destruction facility under construction. The plant is being built to destroy the chemical weapons stockpile at the Pueblo Chemical Depot, in southeastern Colorado.