Contaminants that enter the air without going through a smokestack and, thus, are often not subject to control by conventional emission control equipment or techniques. Most fugitive emissions are caused by activities involving the production of dust, such as soil erosion and strip mining ,or building demolition, or the use of volatile compounds. In a steel-making complex, for example, there are several identifiable smokestacks from which emissions come, but there are also numerous sources of fugitive emissions, which escape into the air as a result of processes such as producing coke, for which there is no identifiable smokestack. The control of fugitive emissions is generally much more complicated and costly than the control of smokestack emissions for which known add-on technologies to the smokestack have been developed. Baghouses and other costly mechanisms typically are needed to control fugitive emissions.