The unlined portion of the tunnel had caved in under the debris of a mudslide on Monday night, burying many workers alive and injuring others.
There were always small rockslides or mudslides happening there.
There have been more mudslides and landslides leading to deaths.
The mudslides were set off on Christmas Day after a downpour fell on hillsides that had been stripped of vegetation by wildfires in October and November.
Dozens of villagers were killed by mudslides on the slopes of the mountain, which rumbled back to life in July, government officials said.
In the northern Cascade Mountains the supposedly dormant volcano Mount Baker periodically oozes clouds of steam over its summit and stains its icy slopes with mudslides .
Effective techniques of fighting the enemy in the mountains are induced rockfalls, avalanches, glacier movements and mudslides .
Torrential is rain still falling, triggering mudslides in Austria.
She explained how her parents' house almost floated out to sea in the recent rainstorms and mudslides .
Aftershocks and heavy rains continue to trigger mudslides on mountain slopes where the quake has uprooted forests, loosened topsoil or created barrier lakes.