10 CFR §13.30

1. (a)The ALJ shall conduct a hearing on the record in order to determine whether the defendant is liable for a civil penalty or assessment under § 13.3 and, if so, the appropriate amount of any such civil penalty or assessment considering any aggravating or mitigating factors.
2. (b)The authority shall prove defendant's liability and any aggravating factors by a preponderance of the evidence.
3. (c)The defendant shall prove any affirmative defenses and any mitigating factors by a preponderance of the evidence.
4. (d)The hearing shall be open to the public unless otherwise ordered by the ALJ for good cause shown.