Treasury OIG should follow-up with DC's management to determine if the remaining grant balance was similarly unsupported and should be recouped or replaced by other eligible expenditures, not previously charged to CRF, that were incurred during the period of performance. Based on DC's responsiveness to Treasury OIG's requests and its ability to provide sufficient documentation, and/or replace unsupported transactions charged to CRF with valid expenditures, Treasury OIG should determine the feasibility of conducting an audit for Grants greater than or equal to $50,000 payment type.