Sleuthing for Roundhouses

Very small roundhouse right off 1A in Revere on Railroad St. Revere Assesor's Dept says 1900 built.

https://www.google.com/maps/place/Railr ... 71.0061022" onclick="window.open(this.href);return false;

That's amazing. Is that an active spur? And what is amazing is what looks like ground-level solar panels. Land must be contaminated or in a flood plain - it should be too valuable, put solar panels on the roof. Or nasty fumes from the petroleum storage tanks.