60 foot long timbers at close spacing necessitated by loose slate roof - Elkhorn Mine.
Photo Details
Source: USGS
Photographer: N/A
Description: 1,250 foot level of the south stope - Elkhoen mine.
60 foot long timbers at close spacing necessitated by loose slate roof - Elkhorn Mine.
Source: USGS
Photographer: N/A
Description: 1,250 foot level of the south stope - Elkhoen mine.
