Excavation of fill for highway construction outside highway rights of way shall be permitted only in "S-1" and "AF" Districts and only after approval of Council is granted. The construction contractor shall provide proof that the source of community water supply shall not be adversely affected due to lowering the water table or contaminating the supply before permission for excavation is given in "S-1" or "AF" Districts. The contractor shall also submit a plan and description as to the manner in which public utilities, roads, and surface drainage are to be restored in those instances where such facilities are to be disturbed by the excavation.