Los Alamos Reports Success in Tests of Mine Communications System
RIGOROUS testing at the Lake Lynn Experimental Mine last month proved the viability of Vital Alert Technologies' system for emergency warning, evacuation, and rescue communications, Los Alamos National Laboratory (LANL) officials announced on Aug. 6.
Developed by LANL, the Through-The-Earth Communication system proved capable of sending two-way, very-low-frequency (VLF) voice signals from the surface of the mine to depths exceeding 300 feet at the experimental mine operated by NIOSH.
The technology is capable of allowing first responders, rescue teams and underground miners to communicate with each other in extreme environments such as subways, tunnels, skyscrapers, and mines, during emergency situations. Through-The-Earth Communication™ will offer high-level security to managers of critical government, industrial, military, commercial and public infrastructure. It also can be used by first responders in the advent of terrorism and natural disasters, such as hurricanes, earthquakes and floods.
In deep underground mines, the reliable and portable system will provide two-way voice reception that can be used to locate trapped miners and alert people of underground conditions caused by blasts, fires or structural collapse.
The Through-The-Earth Communication system was developed for the U.S. Department of Energy at LANL's Superconductivity Technology Center with a development team led by David Reagor. The technology also has earned a prestigious R&D 100 Award from R&D magazine.
The system uses VLF electromagnetic radiation in the range of 3 to 30 kilohertz (kHz) and digital audio compression to transmit wireless voice and data signals through the earth. Materials that block higher radio frequency (RF) signals, such as rock, concrete, metal, and high-density ore bodies, do not restrict its signal. Unlike RF devices, the new technology does not rely on line-of-sight signal transmission or hard-wiring. The system can be coupled with conventional RF equipment to provide enhanced communication coverage both above and below ground.
Incorporating Sprint/Nextel i325 mobile phones, supported by Raytheon's JPS Communications ACU 1000 cross-band repeaters, the Through-The-Earth Communication system demonstrated its capabilities in the Lake Lynn Mine, which is composed of several long tunnels used for mine safety experiments. The mine consists of nonflammable limestone with a tunnel height of about 10 feet and an overburden of up to 370 feet.
In response to the Sago and Alma mine accidents, MSHA in 2006 solicited proposals to evaluate communication and tracking system technologies in underground mines that could improve communications and benefit search and rescue efforts. More than 100 proposals were submitted and six systems were selected for further consideration. Vital Alert responded with a proposal in anticipation of the prototype system that has since been developed in partnership with LANL.
In May 2007, Vital Alert notified representatives of MSHA and NIOSH that its system was available for testing. Vital Alert requested the opportunity to demonstrate its new wireless capabilities and was subsequently invited to conduct testing at the Lake Lynn Experimental Mine.