That's right, the white sheets are to avoid spilling the sea, in the same way they fall waste to the sea, but in smaller quantity.

I do like the white sheets between ship and shore, presumably to catch spillage from the grabs. How environmentally considerate!
Holedriller

The bus is also for the transfer of the personnel that works in the port, to move inside the terminal and out of the port..

Bus for regular turning crew go ashore?

Very busy day