Step 3: Facilities requiring permit coverage must assess for pollutants

How do I assess for pollutants at my facility?

All facilities requiring permit coverage must assess for industrial activities and materials, and consider the potential pollutants that can come from these activities and materials

Review outdoor significant materials

Here’s a general list of significant materials that can cause contaminated stormwater runoff:


  • Fuels, solvents, coolants, lubricants and cleaners
  • Raw, intermediate, and final products
  • Metallic materials
  • Chemicals
  • Wastes and scrap materials
  • Hazardous materials/wastes
  • Processing or production operations
  • Machining fluids
  • Dust or residuals
  • Fueling stations
  • Above-ground tanks for liquid storage

Review industrial activities

Here’s a general list of industrial activities that can cause contaminated stormwater runoff:


  • Outdoor storage activities
  • Outside manufacturing areas
  • Vehicle & equipment washing, maintenance and storage areas
  • Loading and unloading operations
  • Fueling of vehicles and equipment
  • Other substance transfer areas
  • Outdoor manufacturing or processing activities
  • Significant dust or particulate generating activities
  • Onsite waste disposal practices
  • Outside storage areas for raw materials, by-products, and finished products
  • Grinding, cutting, degreasing, buffing, and brazing
  • Industrial waste management areas (landfills, waste piles, treatment plants, disposal areas)

Implement a Mercury Minimization Plan, if required

Any time mercury sources or devices are found to be exposed to stormwater, a Mercury Minimization Plan shall be developed that describes how mercury sources will be managed at the site to eliminate exposure to precipitation and stormwater runoff. The mercury sources and devices shall be removed from stormwater exposure and managed in accordance with Minn. R. 7045, Hazardous Waste, and any additional applicable state and federal rules.

Go to Step 4