Particulate matter (PM) is one of the primary pollutants produced from surface mining operations. Exposure of mine workers to PM in opencast mines is of major concern because of associated adverse health impacts. Dispersion studies of PM generated during opencast mining until now have mostly been confined to estimation of emissions from individual mining operations as well as total emission from an opencast mine. PM dispersion inside the mine since its generation until it escapes the mine is important particularly for deep opencast mines where mine workings are confined to bottom benches and emission from it passes across all benches before it reaches surface, thus affecting the exposure level of workers at higher benches. The book presents a review of health impacts due to inhalation of particulate matter with special reference to emissions from mining, PM emission estimate methods and highlights the need of in-pit PM dispersion estimate. With the case studies in three non-coal mines in India, a few approaches for in-pit PM dispersion has been suggested. The exposure level of workers who are working away from the source can thus be estimated by this approach.