TES was engaged to obtain concurrence from State and Federal regulatory agencies that materials produced by a company engaged in the production of potassium hydroxide from oil refinery scrubber liquids were not solid wastes. TES prepared correspondence and supportive materials regarding the regulatory status of products produced from spent materials and by-products generated during the petroleum refining process. The negotiations concerning the status of the products produced by the TES client took place over a 14-month period. After meetings in EPA’s Region VI office and teleconferences with the Office of Solid Waste in Washington, D.C., TES was able to obtain the Agency’s concurrence that the spent materials and by-products emanating from the refineries were not “solid wastes” as defined in 40 CFR Part 261 and would not, therefore, be subject to regulation as hazardous waste, even if the materials expressed a hazardous waste characteristic. TES was able to obtain written concurrence of the Agency’s position from the Pennsylvania Department of Environmental Protection, the California Environmental Protection Agency, the TCEQ, and the Louisiana Department of Environmental Quality (LDEQ). Subsequent to obtaining concurrence from the regulatory agencies, the client constructed facilities to accept refinery by-products in Illinois, Louisiana, Georgia, and Pennsylvania. TES was engaged to obtain the regulatory authorizations necessary to construct and operate all five of the constructed facilities.