60hrs mon thru fri ,off duty sat and sun and then works 12hrs the following mon is the driver in violation?

Nope,you had a 34 hour break,once youve done that you have a fresh new 70/8 hours.The only way you could have violated the hours of service is if you exceeded 11 hours driving time in any one day.Since you can only legally drive for 11 hours,with 3 on duty not driving.As long as you dont exceed with over 14 hours daily.(unless your day only has on duty,not driving time.Than could go on forever under the clock,but the minute your behind the wheel,the 14 hour rule starts.( also under a unforeseen circumstance,you can legally drive over 11 hours in an emergency)