The report characterizes multimedia emissions from external combustion sources for electricity generation. Study results indicate that external combustion sources for electricity generation contribute significantly to the nationwide emissions burden. Flue gas emissions of NOx, SO2, and particulate matter from these sources account for approximately 50, 57, and 25%, respectively, of these pollutant emissions from all stationary sources. Additionally, flue gas emissions of sulfates and several trace elements from coal- and oil-fired utility boilers also require further attention. POM compounds in flue gas emissions are mostly naphthalene, phenanthrene, and pyrene. However, dobenz(a,h)anthracene and possibly benzo(a)pyrene, both active carcinogens, were detected at a limited number of coal-fired sites. A second major source of air emissions is vapors and drifts from cooling towers. Air emmissions of Cl, Mg, P, and sulfates from mechanical draft cooling towers were found to be comparable to flue gas emissions of these pollutants from oil-fired utility boilers. The multiple use of water in steam-electric plants results in wastewater streams from several operations. Overall, concentrations of Fe, Mg, Mn, Ni, and P are at levels that may be harmful. Average organic levels ranged from 0.01 mg/l for ash pound effluents to 6.0 mg/l for boiler blowdown. No POMs were detected.