Upon approval of an application, the applicant shall deposit with the city, cash in the form of a certified check or a construction bond in the amount of $5,000 as security for the proper restoration of the street to the condition which it existed prior to the excavation. If cash is deposited as security, it shall be held for a period of one year to guarantee the restoration work for a period of one year. The applicant may then proceed to open up and excavate the street.