Survival cache 1
From camp Greek Fire storage climb up the stairs, along the row of shrines. The cache is on the ground, at the end.
Survival cache 2
Under the collapsed planks, near the second Greek Fire container, which you need to find during the main storyline.
Survival cache 3
Near the first Greek Fire container, which you need to push into the water to blow up the sculpture. Examine the recesses in the corridor on the left.