Mine Roof News Today

Thats a large distance for people on the surface to be able to detect someone pounding not on a mine roof in this case, on the roof of the refuge chamber. but its something that we think is important to at least try to do. >> have you ever found anybody alive after that where you havent heard pounding? >> we have not. >> weve done seismic tests throughout the country but have not rescued anybody with the use of the seismic equipment. >> have you done that in this situation? >> this will be the -...