Abstract: At approximately 5:00 a.m. on February 8, 2014, Employee #1, of Corey Delta Constructors Company, a K2 Pure Solutions operator, was depressurizing a line that contained chlorine gas. Two attempts were made to depressurize the line. The first attempt resulted in a small chlorine release and employees having to evacuate to shelter and the second attempt resulted in the employee opening a valve upstream of the 2 in. bleed valve releasing chlorine gas through an open flange connection downstream exposing coworkers, and requiring a plant evacuation. Employee #1 was transported to an area hospital, where he was treated for inhalation exposure to chlorine gas.