§ 98.35  FILLING.
   All excavations and holes shall be refilled with fine gravel compacted to approximately 85% or with fill dirt as prescribed herein.  In the event fill dirt is used, a layer of 18 inches of gravel shall be used in the bottom of such excavation, and the fill dirt shall be compacted with power compacting equipment in succeeding layers each not to exceed six inches in depth.  Permission shall be obtained from the Building Commissioner at the time of issuance of a permit, and shall be indicated on the permit, for the use of fill dirt in refilling excavations.  After the compaction fill with gravel has been completed, the fill must be sealed and finished with standard mix bituminous paving material, also compacted.
('80 Code, § 22-23)