Final answer:
A written route plan is mandated by the United States Department of Transportation and EPA regulations for the safe transportation of hazardous materials on public roads, highways, rails, and waterways.
Step-by-step explanation:
A written route plan is required for transporting hazardous materials to ensure safety and compliance with government regulations.
This requirement comes under the jurisdiction of the United States Department of Transportation (DOT) hazardous materials regulations and the Environmental Protection Agency's (EPA) hazardous waste regulations. The need for a route plan is critical because transporters are moving regulated wastes on public infrastructure such as roads, highways, rails, and waterways.
A clear and detailed route plan helps in managing risks associated with the transport of hazardous materials and ensures that all safety measures are adhered to during the journey.