Team Trainer Test No. 5 Taken from the 2016 Northern Regional Team Trainer Contest held in Clymer, NY Progress Indicator: Question 1 of 30 1.  For single-level, room-and-pillar shaft mines, the initial fresh air base can be set up on the surface and then moved to a drift, entry, or crosscut underground close to the affected area.  The fresh air base should never be left on the surface during the entire operation. Choices: True False