If the Planning Commission finds that land proposed to be subdivided is unsuitable for subdivision development due to poor drainage, flood hazard, topography, inadequate water supply, landslip potential, unstable subsurface conditions due to underground mining or other reasons and other such conditions which may endanger health, life, safety, or property; and, if by any public agencies concerned it is determined that in the best interest of the public the land should not be developed for the purpose proposed, the Planning Commission shall not approve the subdivision unless adequate methods for solving the problems are advanced by the subdivider. For major subdivisions, a written statement may be required by the Planning Commission describing characteristics of the development site, such as bedrock geology and soils, topography, flood prone areas, existing vegetation, structures and road networks, visual features, and past and present use of the site.