Unemployment rate: Bachelor's Degree or Higher 4.1%
Overall Unemployment Rate___
White rate: 7%
Black rate: 13.4%
Between those two BLS data points it is reasonable to assume that the white college graduate rate is somewhat lower than the 4.1% overall rate for college graduates. (Though not half, like the overall rate.)
The white college graduate unemployment rate is somewhere in the high 3% range, which meets any economic definition of full employment. (Full employment is not 100% employment, it is the maximum employment sustainable without large increase in inflation. Current national full employment is thought to be somewhere in the 3.5%-4.5% range.)
http://www.deptofnumbers.com/unemployment/demographics/