It's best to manage personal information digitally. Having to browse printed documents makes it difficult to control access rights as well as appropriately log the process. Where digital personal information should be stored depends on each case, but one thing that is certain is that it should be centralized.
This means someone other than the list manager should periodically check to make sure the information really is managed in one place (task 4. in the below workflow).
One more thing... to avoid burdening the supervisor too much, the below workflow gives this task to a separate employee.