Floor and terrain not loading/buging

So when I load into a game the floor will not load. I can see rocks that are different from the actual terrain. It also says that i can open my parachute. There is also times when playing on exposure that when I get to the tunnel it has terrain over it. So basically I have to run into it and it stops me then puts me through it. The entrances to the tunnels i cant go through because the terrain is bugging. I've tried to update my drivers and that didn't work. I tried to repair the game and it didn't work. I've uninstalled and reinstalled and still didn't work and i cant find anyone else with this problem. (sorry for crappy picture my screenshots weren't working)