[She notices the wince, and if she was the type to pry into personal business or just reactions more, she might have asked what caused that reaction. As it was, she merely tilted her helm.]

If I'm reading the heat-fluctuations in the area right, those tunnels are probably for those incapable of traversing over-ground when the heat-wave hits its peak... Because it's still rising, and if it continues, a human, say, wouldn't be able to handle it.

So it's probably as safe as it can be, to provide an alternate route.