(a) If any taxpayer neglects or refuses to make a return in payment of taxes as required by this article, the finance director shall make an estimate, based upon such information as may be available, of the amount of the taxes due for the period for which the taxpayer is delinquent, and shall add thereto a penalty equal to ten percent thereof and interest on such delinquent taxes at the rate of one percent per month, or fraction thereof, from the date when due.

(b) Promptly thereafter, the finance director shall issue a notice of assessment to the delinquent taxpayer of such estimated taxes, penalty and interest.

(c) Such assessment shall be final and due and payable from the taxpayer to the finance director within 20 days from the date of issuance of the notice; provided, however, that within such 20-day period, the delinquent taxpayer may petition the finance director for a hearing on such assessment as provided in this article. (Code 1979, § 36-166)