this news is a bit misunderstanding, in fact, not one 1000 km tunnel, many tunnels should be dug in this project.First of all, I assume its really 100km not 1000 as it's stated in OP.
Second, clearly you have no idea, what you is 100km tunnel.
Some vertical vents!? Have you ever seen one in any tunnel?
If some how ventilation issue is resolved in 100km tunnel by some magical engineering, evacuation would be impossible!
There would be requirement of hospitals and restaurants, what's your Indian engineering solution to that?
many proposals were submitted to Congress, the most well known proposal is Guo Kai 's Big West Line proposal, in his proposal, the longest tunnel is 60 km, the shortest is 6 km, 8 tunnels should be dug, total length is 240 km.
tunnel is not the most difficult issue should be solved in this project.