Appropriations made to the Department of the Interior shall on and after December 8, 2004, be available for operation of warehouses, garages, shops, and similar facilities, wherever consolidation of activities will contribute to efficiency or economy, and said appropriations shall be reimbursed for services rendered to any other activity in the same manner as authorized by sections 1535 and 1536 of title 31: Provided, That reimbursements for costs and supplies, materials, equipment, and for services rendered may be credited to the appropriation current at the time such reimbursements are received.