Provided, however, when the Board of Aldermen determines that strict application of the paving requirement will constitute unnecessary hardship on the property owner and will prevent the reasonable development of the property which is in the best interests of the City of Duquesne, and also determines that failure to strictly apply the paving requirement will not adversely affect the rights of adjacent property owners and will not adversely affect the public health, safety, quality of life, order, convenience, prosperity or general welfare, then, with the advice of the Planning and Zoning Commission, the Board of Aldermen may issue an exemption from the paving requirement for a period not to exceed five (5) years in duration.