Oh now I know why - (joke, but this shows the beginning of a pattern of behaviors)

Drug screens bar 80 workers from Vogtle site

Eighty contract workers were denied access to — or evicted from — Plant Vogtle after failing drug tests during 2011, according to reports filed with the Nuclear Regulatory Commission.

According to the individual reports, which did not name the workers involved, the failed tests during 2011 included positive results for alcohol, marijuana, cocaine and amphetamines. Workers who refused to submit to a test were counted among those who failed — and were permanently denied access to the site.

Source - [link to chronicle.augusta.com]