I fought and worked in these type of areas most of my career and a lot of planners at the time went with regular sprinklers at the time. Product changes at unknown times and what may have been good at the time of the initial construction may not be good now. Foam systems are also limited to the amount of product stored in the tank, how old and last time it was tested. When the foam runs out (which is surprisingly quick) it just flows water and washes the other product away.
A lot of these places also have runoff containment somewhere on the property if the room is available.
One of the Gasoline storage and distribution plant has sub-surface injection built back in the 70's, deluge system in the truck filling area and automatic fixed monitors with foam attached around the property. The main deluge system had a 500 gal tank if I remember correctly, auto monitors had wither totes or 55gal drums attached and the sub surface had nothing in them. We had to have the foam that was stored on site delivered to the injection stations so we could feed from there. Our nearest large quantity of foam (not from an airport) was 35 miles away where they had 15,000gal available to move in 15min, but still took time to get here, so we were on our own until then.
Another town that was built later with the same operation like ours was not constructed with subsurface, auto monitors but had a deluge system on the filling racks.
About 6 years ago we had a chemical plant go up like this and we did the same thing by drowning the living daylights with water to contain the fire until we could get enough foam and an ARFF vehicle to the place. We had to reposition rigs several times due to changes in the wind and the flow of water. I do remember wading through waist deep chemical impregnated water trying to keep the storm drains open to facilitate the drainage to the creek behind the plant.
While we were doing the suppression and haz-mat there, we had the surrounding division team and the county wastewater commission take care of the runoff by stringing booms and such as the incident progressed.