We are required to work 40 hours a week, though with a recent addition to our work requirements we are now adding 20 hours Mandatory OT to that each month.  So in 4 weeks we would work 160 regular hours and then 20 hours OT.  They are being "nice" and letting us come in on Saturdays (up to 8 hours) or we can work an additional 1-2 hours each day, but on assigned work for that time, meaning whatever you were doing at the 'end' of your day gets put away and you switch to the assigned OT work.  Oh... and this mandatory OT will go from now till October, so there goes the summer!  Yup, you can tell I'm thrilled.