Notwithstanding the provisions of § 46.2-2078, upon a showing of public convenience and necessity, the Department may, if it finds from the evidence that the public interest will be promoted thereby, issue to any carrier of passengers by motor vehicle a certificate or certificates authorizing operations in the Commonwealth upon highways that are part of the Interstate Highway System. The foregoing shall be applicable only to issuance of certificates for operations over such System. Except as otherwise indicated, all other applicable provisions of this chapter shall apply to such carriers and to such certificates.