If the person so served fails to abate the nuisance within seven (7) days, the superintendent of public works may proceed to abate such nuisance keeping an account of expenses of such abatement including labor and equipment charges based upon the prevailing wage rate paid to any city employee assigned to work in abating the aforesaid nuisance and the prevailing rental rate of any equipment used by the city in conjunction with such abatement. (Ord., 6-16-1980)