Miners were able to construct a passage through the debris from the collapse to reach the trapped workers. Food and water had been passed through a narrow steel tube to the trapped workers from soon after the collapse, but attempts to reach the men had been hampered by the poor ground conditions. The rescuers were first able to contact the tunnel workers shortly after the collapse, which happened on November 12th and air was also pumped into the tunnel from that time on.
Drilling equipment was used at first to attempt a rescue but was unable to get to the men due to the loose material. But the area is known for its difficult geological conditions and is prone to earthquakes, landslides and flooding, which delayed the rescue further.
The tunnel was being constructed through a fault zone at the time of the collapse. Located in Uttarakhand, the new tunnel is intended to form part of the Brahmakhal-Yamunotri National Highway. The topography of the area is very mountainous, which is why the tunnel is needed to form part of the highway route. The reasons for the collapse are now being investigated.