The correct answer is letter A
National Pollutant Discharge Elimination System (NPDES) was developed by the federal government and is being implemented by the local and state government to address environmental problems created by stormwater runoff from developing properties.
The city of Marshall is required by the US Environmental Protection Agency (EPA) and the Minnesota Pollution Control Agency (MPCA) to reduce rainwater pollution for surface and groundwater. The city is required to operate with a Minnesota NPDES MS4 license and therefore the city of Marshall is a designated MS4. The MS4s designated by rules are cities and towns with a population of less than 10,000 and cities and towns with a population of 5,000 and discharging into valuable or polluted waters.
The main objective of the NPDES MS4 license is to restore and maintain the chemical, physical and biological integrity of the state's waters through the management and treatment or disposal of urban rainwater. As part of the NPDES MS4 license, the City of Marshall was required to develop and implement a Storm Water Pollution Prevention Program (SWPPP).