| egulations, such as the MINER Act of 2006, require the installation of redundant and secondary communication systems to assure that contact can be established with coal miners who may become trapped underground as a result of an event such as a fire, explosion, or inundation. For half a century, the orientation towards underground communications has been that more complex systems better serve the coal miner. However, if the goal is to provide for a reliable means of establishing communication between the surface and trapped miners underground, then the technology employed should be simple, reliable, and cost-effective. Coal mines spend hundreds of thousands of dollars on exploratory drillholes to characterize reserves, sometimes decades ahead of mine development. During the pre-planning phases, certain exploratory drillholes could be located and then outfitted with a simple communication link which would remain compatible even with the continuing evolution of communication systems. These links, whose locations would be accurately recorded, would be exposed by continuous miners during mine development thereby allowing an underground phone to be connected to a surface station in the event of an emergency. A latent network of these communication links could be installed for less than... |
