If unpaid as of the date specified in the Administrative Order, the administrative penalties, administrative costs and interest assessed by the officer shall be collected by the city by use of all available legal means, and may be enforced as:

(a) A personal obligation of the violator; and/or

(b) If the violation is in connection with real property, a lien or special assessment upon the real property. The lien or special assessment shall remain in effect until all of the administrative penalties, interest and administrative costs are paid in full. (Ord. No. 2423 (NCS), § 1.)