Improved drilling of coal measure rocks for underground mine void detection and exploration programs

Author:	Watson, Pamela J.
Additional Authors:	Pahlman, J. E., Tuzinski, Patrick A.
Year:	1991
Document Type:	BMRA
Issuing Agency:	U.S. Dept. of the Interior, Bureau of Mines,
SUDOC:	I 28.22:9370
Series:	Report of investigations / Bureau of Mines ;
Report Number:	9370
Subjects:	Abandoned coal mines
	Mine surveying
	Coal-cutting bits
	Polyethylene oxide
Link:	https://hdl.handle.net/2027/mdp.39015077558198