Consistent with the general purposes of the City of Newburgh Zoning Law, the Supplementary Regulations set forth environmental constraints to control potentially objectionable external aspects of all uses. The regulations require specific conditions for steep slopes (greater than 15%): adequate erosion control and drainage measures must be in place to prevent erosion and sedimentation; the cutting of natural vegetation must be minimized; safety hazards such as subsidence, road washouts, landslides, flooding, or avalanches must be prevented; and proper engineering review must be conducted by the City to ensure compliance.