I agree.
This is probably the old foundations for an aerial crane to transport the (coal?) that was strip mined nearby.
You can see on the topo that the road to transport the coal only goes so far, and then it's still a couple hundred feet above the Coxton Yards where the coal was undoubtedly transported by train. The Susquehanna River is not navigable by coal barge at this location because the water is too shallow, and the bridges are not tall enough.
As for the "round thing" - there are two round things nearby.
One is an old locomotive turntable centered at coordinates: 41.35261, -75.80060.
I think this is technically called a "Roundhouse". (?)
The other round "thing" just looks to be a retention pond, possibly related to the prior mining activity (?).
This pond is located at coordinates: 41.35399, -75.79810
Using the tilt feature in Google Earth, you can pretty clear see it's designed for retention (see Yellow arrow).
It looks like it has a pipe running through the middle, so this could also have been a storage tank retention pond.
Abandoned train tressel at red arrow (likely went to locomotive turntable).
Either that, or a meteor hit it. Does sort of looks like a perfect crater
