Treasury OIG should request DC to provide support for replacement expenses, not previously charged, that were eligible during the CRF period of performance for the $148,721 of ineligible costs charged to the Contracts greater than or equal to $50,000 payment type. If support is not provided, Treasury OIG should recoup the funds. Based on DCs management's responsiveness to Treasury OIG's requests and its ability to provide sufficient documentation and/or replace ineligible transactions charged to CRF with valid expenditures, Treasury OIG should determine the feasibility of conducting an audit for the Contracts greater than or equal to $50,000 payment types.