Exhaust pipe termination

I am a new inspector and this inspection was a practice done on a house in the neighbor. The house had an electrical fireplace insert. The original fireplace was factory-built. When I went up in the attic, this is what I saw. I know that the chimney is not being used. What is the smaller exhaust pipe for and how should it be terminated? Thank you.

Fresh air intake that is no longer being used?

You would have to trace it to be 100% sure