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U.S. Army Dugway Proving Ground (DPG) is a major defense test range located in the remote west desert of Utah, USA. DPG is made up of various testing facilities, extensive test grids, and impact areas. DPG's mission is testing for chemical and biological defense. Recently, a series of large-scale chlorine releases were held at DPG, known as the Jack Rabbit II test program. The purpose of the testing was to better define public safety parameters in the event of a large-scale chlorine release. DPG deployed 100s of point sensors to quantify the test events. Three single-wavelength UV lidar systems were also developed and deployed with the goal of providing a more overall picture of these events. This was an experimental effort using principles similar to Differential Absorption Lidar (DIAL) to estimate chlorine concentration and track clouds downrange. Lidar systems are typically configured with two wavelengths for DIAL measurements. As our effort was experimental and had very limited funds, we used on hand ND:YAG lasers at the 355 nm wavelength only. The second wavelength was later simulated from portions of the data in which no chlorine was present. The main assumption made in using only a single wavelength was that very limited aerosols and other types of chemicals would be mixed with the chlorine cloud. This single-wavelength approach was found to be an effective method for tracking absorbing chemical vapors. We obtained an overall picture of the test event and were able to estimate concentrations in post processing.