T u n n e l i n g
w o r k
o f
a
n o r t h -
s o u t h
l i n e
back
1. Inside of North-south Line Tunnel
2. Compost Toilet Appearance
3. Compost Toilet
This is the compost toilet used at the time of the tunneling work of a north-south line.
It is playing a role in the improvement of work environment.