Player is stuck in a block that not loaded

Steps to reproduce:
1) Start minecraft server with extended memory sizes (java -Xmx1G -Xms1G -jar minecraft_server.jar)
2) Player go to railroad and just was driving an minecart
3) Sometime chunk with the railroad not loaded
4) The player got into this chunk
5) Player stuck. From minecart can't get out

This is the second stuck in this chunk. At first time the problem was solved by teleportation in a random position (tp x y z) from server and death of a player. But I want to not to repeat that feat. Besides, player can not pass this place. Screenshot shows that chunks around is not loaded too.

Mods isn't installed.
Screenshots and logs attached.