David Sheesley, President, Aristatek received his B.A. Physics, B.A. Chemistry in 1961 from Adams State College in Colorado.

Mr. Sheesley was the program manager at Western Research Institute  (WRI) for chemical dispersion, and emergency response technology R&D being conducted under public law in SARA, Title III and the Clean Air Act.  He also managed technical support for the Liquefied Gaseous Fuels Spills Facility/HAZMAT Spill Center (LGFSTF/HSC) under contract with the Offices of Emergency Management (NN-60: NNSA). Mr. Sheesley was the manager of PEAC project for the Emergency Response Program at WRI.   The program scope included contracts with DOE FE, DOE NN-60, EPA, other academic institutions and the private sector.  As a Senior Staff Research Engineer, he has over 30 years of analytical and technical support experience; 12 years of research for the National Center for Atmospheric Research (NCAR) conducting particle and gas modeling research for the National Science Foundation; 4 years experience in monitoring/modeling research nationwide for the Environmental Protection Agency (EPA); 4 years as DOE-FE environmental manager at the DOE Laramie Energy Technology Center; and over 10 years of program management with WRI.

He was one of the American National Standards Institute (ANSI) experts representing the United States in the European Community (EC) for the International Standards Organization (ISO) on stationary source emissions (TC146) and was the U. S. Delegate presenting the U.S. position in Berlin (1975), Budapest (1977), and the Hague (1979).

He is the father of 3 children and has 5 grandchildren.