7 billion kg at the density of water would fit in a cube 200 m on each side.

All the plastic ever produced could be stuffed back into one medium size coal mine. There are thousands of such mines and they are already ecologically disruptive.

It's a large amount when you think about the logistics to move it around the world, but a small amount compared to the total amount of stuff we take out of the earth.

We've produced 6-8 billion tons of plastic/plastic waste and its bulk density is much lower than water

https://ourworldindata.org/grapher/global-plastics-productio...