Is this a sump pit? Can I fill it?

[Bcp]

Hi, wondering if this is a sump pit or not? I don't think it is since the main stack goes through it. But furnace condensate pump drains into the gravel ( clear tube, attached to water line) as well as the dehumidifier (green hose).

Can I fill this with concrete if I reroute the condensate and dehumidifier drains? Or is there advantage to keeping this open as is? Or do you suggest covering it with a custom lid using PVC?

 

[breplum]

Be aware of the fact if you choose to pour concrete to protect the pipe itself from contact with the concrete with rug pad or several wraps of handi foam wrap.
Be aware, that furnace condensate is acidic (so can't go into a metal drain pipe without using an acid neutralizer cartridge, and I imagine in your area, it can't just run it outside because of freezing.