2009-07-06_REVISION - M1977036 (40)

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? ASPHALT PAVING Hot mix asphalt is transported to the project from a production plant located off-site. It is then placed, compacted and rolled according to project specifications. ¦ ASPHALT MANUFACTURING A hot-mix asphalt plant blends together aggregate and asphalt cement to produce a hot, homogeneous asphalt paving mixture, which is then hauled to off--site construction projects.. The aggregate used can be a single material, such as a crusher run aggregate or a pit run material, or it can be a combination of coarse and fine aggregates, with or without mineral filler. The binder material used is normally asphalt cement but can also be an asphalt emulsion or one of a variety of modified materials. Various additives, including liquid and powdered materials, can also be incorporated into the mixture. Activities at these sites may include the following: raw material unloading into stockpiles or storage tanks, raw material feed to plant, material batching, raw material storage area, recyclable asphalt disposal area, truck wash out, and water supply and settling lakes. ? READY MIXED CONCRETE, CENTRAL BATCHING These operations mix sand, gravel, cement, and water together to form ready mix concrete, which is then hauled to off-site construction projects. The raw materials are made up of sand, gravel, cement, water and additives. The sand and gravel is either stored in stockpiles located outside and fed into the plant via loaders and conveyors, or it is stored directly in a series of hoppers located directly above the central plant. The remainder of the raw materials is stored in tanks to protect them from exposure to moisture and temperature until they are pumped into the mixer. Once the raw materials are fed into the central mixer and combined to form Ready Mix concrete, the final product is placed within trucks and removed from the site.. ¦ READY MIXED CONCRETE, DRY BATCHING These operations apportion out a mix of sand, gravel, cement, and water together, which is then mixed within the truck to form Ready Mixed concrete that is hauled to off-site construction projects. The raw materials are made up of sand, gravel, cement, water and additives. The sand and gravel is either stored in stockpiles located outside and fed into the plant via loaders and conveyors, or it is stored directly in a series of hoppers located directly above the central plant. The remainder of the raw materials is stored in tanks to protect them from exposure to moisture and temperature until they are pumped into the mixer. Dry batching then apportions out and dumps the raw materials into the concrete truck-mounted mixer where it is continually agitated and mixed to keep it from hardening before it arrives on the assigned job site.