"Based on what we know so far and where his residence is located, we've just kind of gridded off the properties around there", Sheriff Chad McBride said.
Police began searching for Henderson, since Monday evening.
Deputies said Henderson, 60, was reported missing from his SC home Monday at 3:45 p.m.
Lt. Sheila Cole of the sheriff's office told WSPA someone received an email from Henderson late Sunday night.
"Please keep his family in your thoughts and prayers". Per Fox Carolina, morning crews took over the search effort from the overnight crew at 7 a.m., followed an hour later by mounted search crews.
K-9 tracking teams and Anderson County Technical Rescue was helping with the search Monday night. Clemson Athletics said he didn't go to work on Monday. His work in the office of planned giving involved setting up meetings with donors and ensuring the financial stability of Clemson's athletic programs. Clemson confirmed the news on Tuesday via Twitter.