2 CFR §780.137

The Assistant Administrator, Bureau for Management, or designee as delegated in Agency policy found in ADS 103—Delegations of Authority, may grant an exception permitting an excluded person to participate in a particular covered transaction. If the Assistant Administrator, Bureau for Management or designee, grants an exception, the exception must be in writing and state the reason(s) for deviating from the government-wide policy in Executive Order 12549.