Within thirty (30) days after the receipt of an application, the Zoning Administrator shall either approve or disapprove the application in conformance with the provisions of this Ordinance. All zoning permits shall, however, be conditional upon the commencement of work within one year. One copy of the plans shall be returned to the applicant by the Zoning Administrator, after the Zoning Administrator shall have marked such copy either as approved or disapproved and attested to same by his signature on such copy. One copy of the plans, similarly marked, shall be retained by the Zoning Administrator. The Zoning Administrator shall issue a placard, to be posted in a conspicuous place on the property in question, attesting to the fact that the activity is in conformance with the provisions of this Ordinance.