Game Crash upon Render Distance switching

The game seems to crash whenever the render distance has been switched (too fast, maybe?). Moving the render distance "bar" with the mouse will freeze the game for a few seconds and ultimately crash it. Also, it only seems to happen when in a game. Being on the main menu does not crash the game, so it could be assumed it's a problem related to chunk loading upon render distance switching.

Error Log below

http://pastebin.com/XQpr8Asm