The STATUTORY requirement is that you go to court and file for ejectment of the tenant. Yes, he still occupies the property by virtue of his belongings still being there.
See:
http://www.scstatehouse.gov/code/t12c037.php
I suggest you follow that procedure unless you are willing to take your chances on getting sued for the value of the property, and losing.
If you want to gamble, then I suggest a common sense approach and put the tenant on written notice to retrieve his property by such and such a date or you will dispose of the property by giving it to charity or tossing it in the trash. Deliver the notice personally accompanied by a witness who can later testify as to delivery if necessary.
Keeping or selling any of the items puts you at risk for a lawsuit.
When the deadline passes do what you said you would do.

