Perimeter setback: No building shall be less than 100 feet from the perimeter property line, and no accessory structure shall be less than 50 feet from such line (except for signs and those structures associated with ingress and egress, lighting standards, stormwater management facilities, retaining walls, benches and the like) unless the proposed development abuts a perpetually preserved conservation area, park land or open space, in which case the Township Council may, upon request of the applicant, decrease the perimeter setback applicable to building and accessory structures to a minimum setback of 25 feet. Required rear yards may encroach into a perimeter setback no more than 25 feet.