Preliminary estimates by the U.S. Environmental Protection Agency (EPA) have indicated the potential for significant radiation doses to individuals near elemental phosphorus plants. During plant operations radionuclides associated with particulates and volatile metallic element radionuclides are released to the atmosphere. Of special interest are polonium-210 and lead-210. The purpose of this work assignment is to apprise EPA of the status of emission of radionuclides to the atmosphere. This work assignment involves collection of information on emission control technology related to the development of standards under the Clean Air Act. Each work task is designed as a chapter to be incorporated into a Background Information Document for the elemental phosphorus industry. Topics covered include general description of the industry and identification of plant-specific processes and emissions; plant-specific emission control techniques and costs; anticipated industry changes due to modernization, expansion, or process alterations; and definition of a model elemental phosphorus plant representative of those currently in operation. Three levels of control, ranging from minimum to maximum application of emission control techniques, are defined for the model plant along with estimated emissions and equipment costs.