The contribution cost is established at $2,500 on each newly created lot (not including the original lot) and dwelling unit, as the case may be. The requirements for such fee shall be imposed by the Planning/Zoning Board at the time of minor or major subdivision approval or site plan, and shall be made a condition to be satisfied prior to the subdivision plat being filed with the County Clerk, it being the responsibility of the Planning/Zoning Board Chairman to confirm such payment prior to the signing of a final plat.