Story related, cannot be missed.
You will get this quest from the sheriff entitled "Destroy the Bomb Caches". Essentially you just have to make it through the Shrouded Clan's base while using RC cars to blowup 3 separate bomb caches. Don't worry about bringing a supply of RC cars as the base has both assembled and scrap ones with which you can make use of.
After you finally blow up the 3rd cache, ride the elevator up to safety while taking cover as guys will be shooting at you on both sides. As soon as the elevator reaches the top, achievement unlocked.