The DOT said the company failed to test the driver for drugs and alcohol after the December 30 crash . U.S. Department of Transportation bans Canadian bus company in fatal accidents . Driver in bus that killed nine worked 92 hours in seven years , report says . Bus firm Hong Joo Tour & Travel Company has history of violations , records show .
U.S. Department of Transportation bans Canadian bus company in fatal accidents . Driver in bus that killed nine worked 92 hours in seven years , report says . Bus firm Hong Joo Tour & Travel Company has history of violations , records show .