;Contents: Introduction--(Proposed amendments to NOx standard, overview of nitrogen oxides problem, and emission factors for electric power units); Description of project at Southern Illinois Power Cooperative, Marion, Illinois--(New cyclone furnace, emission information, ambient concentrations and model results, and economic factors for gob refuse usage); Information on control alternatives--(Characteristics of cyclone furnaces, control methods for NOx abatement, flue gas treatment of NOx); Cost of NOx control--(Combustion modification costs, flue gas treatment, and macro-scale economics); Environmental benefit considerations--(Introduction, evaluation of NOx effects on health and welfare, and conclusions).