Prior to a plant being approved, or the inauguration of in-plant inspection services, and at such intervals as may be deemed necessary or appropriate, the Administrator will make, or cause to be made, a survey and inspection of the plant where such inspection services are to be performed to determine whether the plant and methods of operation are suitable and adequate for the performance of such service in accordance with:
(a) The regulations in this part, including, but not limited to, the requirements contained in §§ 52.81 through 52.83; and
(b) The terms and provisions of any contract pursuant to which the service is to be performed: Provided, That, such survey(s) shall be repeated at least yearly.