Such cash deposit, certified check, irrevocable bank letter of credit or bond shall run to the City and shall be forfeitable by its terms and conditions, automatically, 15 days after notice to the applicant that the requirements of the site plan or this chapter have not been met according to the terms of the temporary certificate or a time specified in the building permit. Such cash deposit, certified check, irrevocable bank letter of credit, or bond shall be considered posted with the condition that upon passage of said 15 days after such notice, in writing, by first-class mail at the last known address of the applicant, such amount shall automatically be transferred to the City of Roseville, or otherwise enforceable by the City by any means available. Thereafter, the City shall be authorized to go onto the property and complete the construction in accordance with the site plan requirements with the funds available. The City may retain 20% of the cost of such completion as the City construction administrative expense and refund any balance to the applicant. No part of an irrevocable bank letter of credit or surety bond shall be released until all of the work is complete. In the case of a deposit of cash or a certified check, portions of said amount may be rebated as work progresses, at reasonable intervals, provided that at all times the amount on deposit shall equal the cost of the work to be completed.