Upon the failure, neglect or refusal of any owner or agent thereof so notified to cut and remove such weeds, grass or deleterious unhealthful growths or other noxious matters growing, lying or located upon such owner's property, or upon the sidewalk abutting same, within seven days after receipt of the written notice herein provided for, the Chief of Police as Health Officer is authorized and empowered to pay for the cutting and removal of such weeds, deleterious and unhealthful growths or other noxious matters, or shall order the removal by the City. In the event that such notice provided for in Section 547.02 cannot be personally served upon the owner or agent thereof, and that such notice provided for in Section 547.02 by registered mail addressed to such owner or agent thereof is returned to the City Post Office because of its inability to make delivery thereof, within thirty days after the date of such notice returned unserved, the Chief of Police as Health Officer is authorized and empowered to pay for the cutting, destroying or removal of such weeds, grass or deleterious unhealthful growths or other noxious matter or to order the removal by the City. (1-9-78.)