You're called to a hobby farm because a farmer tripped over a pipe, fell into a sewage tank, and started drowning before a neighbour pulled him out. When you arrive on the scene, the patient is reluctant to open his eyes because he doesn't want more sewage in his eyes, but he eventually does, but promptly closes them once you've seen they can open. You ask him what happened, and he clearly explains to you what happened. What is his GCS?