Balance of plant(BOP)

I am just guessing but it may be a matter of context. B.O.P. (Balance of Plant) is a valid term. However, that B.O.P. would only be fitting when used in a statement such as.

"The primary process units and the secondary process units will be the responsibility of the ABC Engineering company. The Utility plant and the B.O.P. will be the responsibility of the XYZ Engineering company."

The B.O.P. in this case might include facilities such as: the Raw Water Treatment; the Waste Water Treatment; the Feed Tankage; the Product Tankage; the Truck and Rail Shipping Facilities; Admin-Warehouse & Safety Buildings; and the Flare.