The Secretary of the Department of Natural Resources and Environmental Control is hereby empowered to expend state funds appropriated to the Department for land acquisition; to make relocation payments and to provide assistance in accordance with the Uniform Relocation Assistance and Real Property Acquisition Policies Act of 1970; provided, that the Secretary must expend funds for this purpose that are federally reimbursable under the Uniform Relocation Assistance and Real Property Acquisition Policies Act of 1970, Public Law 91-646.