A 28-year-old man from northeast Iowa will spend 50 years in a federal prison on child pornography charges.

Casey Bastian of Dubuque pled guilty in December to one count of production of child pornography and one count of receiving child porn. Late last year F.B.I. agents seized Bastian’s computer and found dozens of videos and other images of child pornography. Authorities say Bastian sexually-abused four different girls in the past 12 years.

Bastian, who is 28, was sentenced this week to 50 years in prison. There’s no parole in the federal system so if he lives ’til he’s 78 years old, he’ll have to be on parole for the next 15 years after he’s served his time behind bars.