On the same level (both map file and physical hieght “level”) as the first bullsquid there is a double stacked black crate (with tension straps to join them as one large unit) which I can pick up. It’s huge and awkward and Gordon would never be able to pick it up.
After you dive in to the water, swim under a wall, climb up a ladder, it’s in the next room against the right wall. Near the med station and dead scientist.