Yes, this is totally possible

From what I understood when talking to the Lead environment artist here at Guerrilla Games, we also render around this (somewhere between 1 and 3 million Tri's) per frame.

The trick though is, pc's nowadays can handle this amount, but adding textures and all these kind of shaders and shadowmaps, that's what makes it slow down to a halt. basically you'll have to make a very good manager for this, and it's possible

regards,