What is this thing?
I'm drawing a site plan for an existing wastewater plant and don't know how to annotate the circular "vent" (for lack of a better word) in the pictures linked below.
The "vent" is 3ft in diameter and warm air (above ambient) is exiting from the annular open space.
TLDR; What is the circular object at the top of the access platform?
Submitted May 21, 2017 at 08:45PM by ConformalConic
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