๐โ๏ธโRat Hole Rescueโ
How they did it (India)
In the Uttarakhand tunnel, the auger machine was cutting through the earth and pushing in pipes of 900mm (3ft) diameter through a 60m wall of debris to create an escape passage for the trapped workers.
bbc.com/...
How 'rat-hole' miners freed Indian tunnel workers - BBC News
Men who manually excavated the tunnel to rescue 41 trapped workers are among the poorest Indians.