Any facility that is engaged in a narrative activity or a primary SIC code, as listed in the Multi-Sector General Permit (appendix A — see page 72) needs to apply for industrial stormwater permit coverage or certify for No Exposure.

Primary SIC code and narrative activities

Businesses are designated by their SIC code(s) or by narrative activities, often for Dept. of Commerce or Dept. of Revenue purposes. The codes are typically found on your federal tax forms, located on the upper left of the Schedule C or C-EZ for Sole Proprietors, Form 1065 for Partners, Form 1120 for C Corporations, or Form 1120-S for S Corporations.

SIC and NAICS codes

Narrative activities

If your facility has narrative activity, you must apply for permit coverage. Identify all applicable narrative activities conducted at the facility.

  • A4: Discharges from Wet Decking Storage Areas (Timber Products)
  • C1: Runoff from phosphate fertilizer manufacturing facilities that comes into contact with raw materials/finished products/by-products/waste products
  • D2: Discharges from Production of Asphalt Emulsions Areas
  • E3: Cement Manufacturing Facility, Material Storage Runoff
  • K1: Hazardous Waste Treatment/Storage/Disposal Facility for Discharges Not Subject To Effluent Limitations In 40 CFR Part 445 Subpart A (NOT a hazardous waste generator)
  • K2: Hazardous Waste Treatment/Storage/Disposal Facility for Discharges Subject To Effluent Limitations In 40 CFR Part 445 Subpart A (NOT a hazardous waste generator)
  • L1: Municipal Solid Waste Landfill Areas Closed in Accordance with 40 CFR 258.60
  • L2: Open Or Closed Non-Hazardous Waste Landfill And Land Application Site Not Discharging to Surface Water
  • L3: Landfill That Discharges To Surface Waters Stormwater That Has Directly Contacted Solid Waste
  • O1: Coal Fired and Oil Fired Steam Electric Generating Facility
  • O2: Nuclear, Natural Gas Fired, and Any Other Fuel Source Used For Steam Electric Generation
  • O3: Runoff from coal storage piles at steam electric generating facility
  • S3: Existing and new primary airports with 1,000 or more annual jet departures that discharge wastewater associated with airfield pavement deicing that contains urea commingled with stormwater.
  • T1: Treatment Works with design flow of 1 million gallons per day or more or are required to have an approved pretreatment program under 40 CFR pt 403

Regulated industrial activities

Not authorized

Co-mingled wastewater and stormwater discharges are considered wastewater and a wastewater permit may be required.

Not required

  • NPDES/SDS permit with stormwater requirements: If your individual wastewater discharge permit has stormwater requirements, you do not need to apply for the multi-sector general permit.
  • No narrative activities or primary SIC code: If you do not conduct a regulated narrative activity or regulated Primary SIC code, no permit is required.

>Construction sand and gravel, aggregate, hot mix asphalt, and/or concrete activities

Facilities with industrial activities covered under the nonmetallic mining and associated activities general permit (MNG49) do not need to apply for the multi-sector general permit, including construction, sand, and gravel mines; stone mines and quarries; or hot mix asphalt facilities. The MNG49 permit can cover multiple locations. See the nonmetallic mining page for more information. If a facility has activities beyond not covered by the nonmetallic mining permit, obtain the multi-sector general permit for the location  or portions of facilities that have additional activities (such as local trucking or landfills).

Grain elevators

Establishments primarily engaged in buying and/or marketing grain, or country grain elevators primarily engaged in buying or receiving grain from farmers (as well as terminal elevators and other merchants marketing grain) fall within SIC code 5153, and therefore do not need permit coverage. 

The 29 sectors of industrial activity

Sector Sector description SIC codes
A Timber products SIC codes: 2411, 2421, 2426, 2429, 2431-2439 (except 2434), 2441, 2448, 2449, 2451, 2452, 2491, 2493, 2499
Narrative activity: A4, Logging-discharges from wet decking storage areas
B Paper and Allied Products Manufacturing SIC codes: 2611, 2621, 2631, 2652-2657, 2671-2679
C Chemical and Allied Products Manufacturing SIC codes: 2812-2819, 2821-2824, 2833-2836, 2851, 2861- 2869, 2873-2879, 2891-2899, 3952
Narrative activity: C1, Runoff from phosphate fertilizer manufacturing facilities that comes into contact with any raw materials, finished product, by-products or waste products
D Asphalt Paving and Roofing Materials Manufactures and Lubricant Manufacturers SIC codes: 2951, 2952, 2992, 2999
Narrative activity: D2, Stormwater runoff from asphalt emulsion facility
E Glass, Clay, Cement, Concrete, and Gypsum Product Manufacturing SIC codes: 3211, 3221, 3229, 3231, 3241, 3251-3259, 3261-3269, 3271-3275, 3281, 3291-3299
Narrative activity: E3, Cement Manufacturing facility, material storage runoff
F Primary Metals SIC codes: 3312-3317, 3321-3325, 3341, 3351-3357, 3363-3369, 3398, 3399
G Metal Mining (Ore Mining and Dressing) SIC codes: 1011, 1021, 1031, 1041, 1044, 1061, 1081,1094, 1099
H Coal Mines and Coal Mining-Related Facilities SIC codes: 1221-1241
I Oil and Gas Extraction and Refining SIC codes: 1311, 1321, 1381-1389, 2911
J Mineral Mining and Dressing SIC codes: 1411, 1422-1429, 1442, 1446, 1455, 1459, 1474-1479, 1481, 1499 
K Hazardous Waste Treatment Storage or Disposal Facilities Narrative activities:
K1, Hazardous waste treatment/storage/disposal facility for discharges not subject to effluent limitations in 40 CFR pt. 445 subp. A
K2, Hazardous waste treatment/storage/disposal facility for discharges subject to effluent limitations in 40 CFR pt. 445 subp. A
L Landfills and Land Application Sites Narrative activities:
L1, Municipal solid waste landfill areas closed in accordance with 40 CFR 258.60
L2, Open or closed non-hazardous waste landfill and land application site not discharging to surface water
L3, Landfill that discharges to surface waters stormwater that has directly contacted solid waste
M Automobile Salvage Yards SIC Code: 5015
N Scrap Recycling and Waste Recycling Facilities SIC Code: 5093
O Steam Electric Generating Facilities Narrative activities:
O1, Coal fired and oil fired steam electric generating facility
O2, Nuclear, natural gas fired, and any other fuel source used for steam electric generation
O3, Runoff from coal storage piles at steam electric generating facility
P Land Transportation and Warehousing SIC codes: 4011, 4013, 4111-4173, 4212-4231, 4311, 5171
Q Water Transportation SIC codes: 4412-4499
R Ship and Boat Building and Repair Yards SIC codes: 3731, 3732
S Air Transportation SIC codes: 4512-4581 Narrative activity:  S3: Existing and new primary airports with 1,000 or more annual jet departures that discharge wastewater associated with airfield pavement deicing that contains urea co-mingled with stormwater.
T Treatment Works Narrative activity: T1, Treatment works with design flow of 1 million gallons per day or more or are required to have an approved pretreatment program under 40 CFR pt. 403
U Food and Kindred Products SIC codes: 2041-2048, 2074-2079, 2011-2015, 2021-2026, 2032-2038, 2051-2053, 2061-2068,2082-2087, 2091-2099, 2111-2141
V Textile Mills, Apparel, and Other Fabric Products Manufacturing SIC codes: 2211-2299, 2311- 2399, 3131-3199
W Furniture and Fixtures SIC codes: 2434, 2511-2599
X Printing and Publishing SIC codes: 2711-2796
Y Rubber, Miscellaneous Plastic Products, and Miscellaneous Manufacturing Industries SIC codes: 3011-3069, 3081-3089, 3931, 3942-3949, 3951-3955 (except 3952), 3961, 3965, 3991-3999
Z Leather Tanning and Finishing SIC code: 3111
AA Fabricated Metal Products SIC codes: 3411-3499, 3911-3915, 3479
AB Transportation Equipment, Industrial and Commercial Machinery SIC codes: 3511-3599, (except 3571-3579), 3711-3799, (except 3731 and 3732)
AC Electronic and Electrical Equipment and Components, Photographic and Optical Goods SIC codes: 3571-3579, 3612-3699, 3812-3873