Application of Cross-measure Borehole Technology to Retreat Longwall Mining in the United States.
Cervik-J; McCall-FE; Campoli-AA
Proc 20th Internat'l Conf Safety in Mine Research Sheffield U k 1983 Oct; :13 pages
Prior to 1970, ventilation was the primary method of controlling methane in gobs. Mining regulations require that the methane concentration in the entries adjacent to the gob be 2 vol pct or less. As mining depth increased, gassier coalbeds and surrounding strata were encountered, and acceptable methane levels in the entries adjacent to the gob could not be maintained by ventilation alone. Consequently, surface gob boreholes were introduced as an auxiliary gob gas control method. Surface gob boreholes cannot always be drilled because mining may be under populated areas, topography may be too severe, or access to private property may be denied. The cross-measure borehole technique, which is used in the United Kingdom and Europe, appears to be an alternative method of controlling gob gas. This paper describes joint efforts by the Bureau of Mines and the mining industry to adapt cross-measure borehole technology to multiple-entry retreat longwall mining in the United States.
Proc. 20th Internat'l Conf. Safety in Mine Research, Sheffield, U.k., Oct. 3-7, 1983, 13 Pp