Dear Mr. Robertson:

Reasons for using overland systems in lieu of trucks include:

Cost effectiveness (i.e. conveyors are less expensive)

Environmental friendliness (conveyors are quieter, cleaner, safer, and less disruptive.)

Productivity (conveyors supply constant material flow)

Generally, the primary reason is the cost effectiveness. However, the other factors also are important. The relative importance will vary from urban area to urban area -- depending on the restrictions imposed by local governments.

You should be able to obtain quantitative information from belt manufacturers, conveyor erectors, and overland conveyor users (in the area concerned). Overland systems that are available to you include the Enerka system already posted, regular troughed belt systems, pipe belt systems, Multi-Fold belt conveyor system (Imperial Technologies), and the square belt system. All of the systems mentioned except for the regular troughed belt system provide complete coverage of the product by the belt -- this controls dust and material loss during the overland transport stage, but the systems are more expensive to install and require more attention to preventive maintenance.

Hope this helps. ■