Fugitive Dust Handbook

11.0   Mineral Products Industry

This chapter addresses metallic ores, non-metallic ores and rock, and coal. In the mineral products industry, there are two major categories of emissions: ducted sources (those vented to the atmosphere through some type of stack, vent, or pipe), and fugitive sources (those not confined to ducts and vents but emitted directly from the source to the ambient air). Ducted emissions are usually collected and transported by an industrial ventilation system having one or more fans or air movers, eventually to be emitted to the atmosphere through some type of stack. Many operations and processes are common to all mineral products industries, including extraction of aggregate materials from the earth, loading, unloading, conveying, crushing, screening, loadout, and storage. The operations at a typical western surface coal mine include drilling and blasting, removal of the overburden with a dragline or shovel, loading trucks, bulldozing and grading, crushing, vehicle traffic, and storage of coal in active storage piles that are subject to wind erosion. Fugitive dust emission factors for mining and quarrying activities are based on EPA’s methodology used for the annual National Emission Inventory that includes emissions from extraction of the ore or rock from the earth but not processing activities. Fugitive dust emission factors for processing activities are taken from AP-42 and represent average values based on a number of tests made under a variety of conditions such as material silt content, moisture content, and wind speed. The sample control measure cost-effectiveness calculation spreadsheet presented for this source category involves the use of a wet scrubber for tertiary crushing at a crushed stone processing plant.