Mission: 22 - Operation Water Warfare
Missable (secondary objective). Once the mission starts, make your way toward the secondary objective. Once you're there you will see a large building with fire coming out of a number of windows and doors. For this mission you will only have the fire hose on the fire truck as a weapon, so simply shoot the hose at each one of the fires until they go out (will only take a couple of seconds). The achievement will pop once every single fire has been extinguished.