Exposure of miners to respirable coal mine dust and quartz (14808607) silica at surface coal mines in the United States from 1982 through 1986 was evaluated by job category. Data were collected by coal mine operators and Mine Safety and Health Administration (MSHA) inspectors. Average coal mine dust concentrations were usually well below the MSHA permissible exposure limit (PEL) for all job categories. At least 10% of the samples obtained from some coal preparation factory job areas and most drilling job areas, however, had concentrations that exceeded the 2.0mg/m3 limit. A very high proportion of samples from surface mine driller areas exceeded the quartz PEL. Of all samples collected for highwall drill operators and helpers, 78% and 77%, respectively, were greater than the 0.1mg/m3 quartz exposure limit. The authors conclude that although MSHA compliance data may not be entirely adequate for assessing chronic exposure to quartz, these data and the results of others nonetheless indicate excessive exposure to silica in some surface coal miners. Immediate actions available to improve this situation include increased environmental sampling and medical surveillance, implementation of effective dust control options, and improved training and education programs.