Every permit required by Section 57.105.7.1 shall become void if the work authorized by such permit has not commenced within six months of the date of issuance, or, if the work authorized by such permit has not been completed within one year of the date of issuance. Thereafter, a new permit may be issued only upon filing a new application and payment of the required fees. The Chief may grant extensions of time upon presentation by the permittee of satisfactory reasons for failure to start or complete the work within the required time period.