Mark Hughes, in his book Confederate Cemeteries, Vol 1, says that those who died at Mechanicsville were moved to Hollywood Cemetery, Richmond, Virginia.

http://www.hollywoodcemetery.org/index.html

http://www.sendcoffee.com/richmond/tours/hollywd.html

http://appomattoxudc.tripod.com/id12.html

http://berryweb.com/hollywood1.htm

Since is name does not appear to be in the records, it probably means he is buried in a mass grave.