Apply job aborting with <1 granule size unable to allocate, ASMM on
This answer is based on the discussion had in the comments of the original question.

The primary cause of any ORA-4031 is that the shared pool is exhausted and is unable to allocate new connections to the database. This will cause the database to crash. I am not going to comment if the package that is running the import is just the last straw or if it is the entire problem, architecturally, I am just offering a workaround.

Due to the small nature of the server memory, space is extremely restricted. I would recommend assigning specific amounts of memory to the shared_pool_size parameter in the spfile and bumping up memory usage incrementally each time the issue occurs. This, of course, implies an increase to SGA_max_size and SGA_target_size. Initial sizing and increment size will be left for the author to discuss, but I'd imagine 50m jumps would be small enough to keep the server happy and also have reasonable chances of success to workaround the ORA-4031. 

If memory of the server becomes exhausted before issues begin to resolve, then I would begin digging around the import package load to see if there are inefficiencies with how that procedure is using the shared_pool.