From EPA’s website
Operators of industrial facilities or sites with activities included in one of these 10 categories must obtain coverage under an NPDES industrial stormwater permit, unless conditionally excluded. The list provided below describes the types of industrial activities within each category.
* Category One (i): Facilities with effluent limitations
* Category Two (ii): Manufacturing
* Category Three (iii): Mineral, Metal, Oil and Gas
* Category Four (iv): Hazardous Waste, Treatment, or Disposal Facilities
* Category Five (v): Landfills
* Category Six (vi): Recycling Facilities
* Category Seven (vii): Steam Electric Plants
* Category Eight (viii): Transportation Facilities
* Category Nine (ix): Treatment Works
* Category Eleven (xi): Light Industrial Activity
BEAT NOTE:
* Category Ten (x): Construction Activity *
*Category Ten (x): Construction Activity that disturbs 5 or more acres of land is included in the definition of “stormwater discharges associated with industrial activity.” However, EPA opts to permit these types of activities separately from other industrial activities because of the significant difference in the nature of these activities. In addition, EPA also requires permit coverage for small construction that disturbs from 1 to 5 acres of land. More information about stormwater discharges from construction activities is available.