> Geofoam producers and boosters claim that geofoam actually reduces the environmental impact of a project by allowing for shorter construction times, reducing the need for energy-intensive earth moving machinery, and reducing the carbon footprint of the overall project.

I guess they forgot about all the machinery and oil consumed by the manufacturing process. Granted, the oil is not being burned but polystyrene is not really environmentally friendly itself either: https://en.wikipedia.org/wiki/Polystyrene

I see the economic and engineering qualities, especially when building whimsical parks and so on (which is a frivolous use case). But I can't help but feel this is a perverse way to build natural landscapes such as parks. Imagine what happens when a burrowing animal finds its way onto one of these things? What happens when you have to dig under the foam in the event you need to do so? What about tree roots? What about micro-plastics? et cetera.

This line sums it up nicely:

> It can come as a shock to realize that giant bricks of polystyrene are stuffed below the turf, like silicone implants under the skin of a city.

Perfect for the Instagram generation: a fake city with fake tits.