Load up the map "Island" on Casual with at least one C-255 truck. If you're just goin for the achievement, equip the Log Carriage. If you're wanting to finish the map, attach a short log trailer as well. Drive past the Lumber Mill and turn left at the intersection. Continue taking this road Northeast across two rivers (the C-255 is tall enough so you won't take damage from being in the river) until you reach the Log Station. Load small logs, and then head back the way you came.