This fact sheet addresses how to determine a facility’s primary Standard Industrial Classification code (SIC code) or narrative activity and related common questions.
The questions and answers in this fact sheet are based on Minnesota’s Questions and Answers, developed with the U.S. Environmental Protection Agency (EPA) to clarify EPA document “National Pollutant Discharge Elimination System (NPDES) Storm Water Program Questions and Answers, Vol. 1 and Vol. 2.”
The MPCA’s industrial stormwater permit lists the industries that need a permit. They are listed by SIC code or are explained in a narrative in Appendix D (page 148) of the permit. Listed industries must get a permit or certify that nothing is exposed to stormwater.
For convenience, the regulated primary SIC codes and descriptions of narrative activities are reprinted at the end of this fact sheet starting on page 10.
SIC codes are a way of classifying industries by 4-digit codes. It is a descriptor of the kind of work being done at a facility, not a number specifically assigned to the facility like a tax ID. Facilities can have several SIC codes but only one Primary SIC code.
The IRS uses SIC codes, so your tax paperwork or accountant may already have the facility’s SIC code. Look on these federal tax forms:
A searchable database of the SIC Codes is available here
Example: A company manufactures metal washers and hinges. Searching for the word “washers” on the linked OSHA website returns a few options. One of them – SIC 3452: Bolts, Nuts, Screws, Rivets and Washers – covers the washers, but not the hinges. Searching for “hinges” returns SIC 3429: Hardware Not Elsewhere Classified. Although hinges aren’t mentioned in the title for SIC 3429, they are specifically listed in the description. Be sure to read the descriptions because they frequently offer the SIC codes for related activities.
If a facility has more than one SIC code, the activity that generates the greatest revenue is the Primary SIC code. If revenue information is unavailable, use the SIC code for the activity with the most employees. If employee information is also unavailable, use the SIC code for the activity with the greatest production.
No, only one permit or No Exposure certification is required; it will address all the operations at the facility.
If the facility fits one of the listed narrative activities, a permit or No Exposure certification is required regardless of whether or not the facility’s Primary SIC code is listed. But if the facility isn’t described by a listed narrative activity and its Primary SIC code isn’t listed, a permit isn’t required even if a Secondary SIC code is listed. See Table 1.
Yes, when the facility applies for the permit, list the Secondary SIC codes in the application. Comply with the sector requirements for the all the SIC codes at the facility and any narrative activities.
Certain industries are easier to define by explaining what they do in a narrative paragraph. They are listed as narrative activities. If a facility fits any of the listed narrative activities, whether for Primary or Secondary operations, it must get an industrial stormwater permit or the No Exposure exclusion.
Summary of when a permit it required based on SIC codes and narrative activity
Link to this table
|Is the facility’s industry type listed?||What to do|
|Primary SIC code||Secondary SIC code||Narrative activity|
|Scenario 1||Listed||Listed or not||Listed or not||Apply for permit or certify No Exposure|
|Scenario 2||Not listed||Listed||Not listed||No stormwater permit required|
|Scenario 3||Listed or not||Listed or not||Listed||Apply for permit or certify No Exposure|
There are a few things a facility can have outside and still qualify for the No Exposure exclusion:
More information is in the MPCA stormwater factsheet #wq-strm3-13, “No Exposure: Qualifying for and maintaining the exclusion.”
A storm-resistant shelter can be:
Wastewater discharge permit
If a facility has a wastewater discharge permit that already includes stormwater requirements, a separate industrial stormwater permit is not required.
See Question 19 for wastewater treatment facility information.
Certain sand and gravel, stone, concrete and hot mix asphalt facilities qualify for the nonmetallic mining water permit. The MNG49 permit includes industrial stormwater requirements and has the advantage of covering multiple locations and portable plants under one permit. If a facility has MNG49 and all industrial activities at the facility are addressed in the permit, the facility does not need the industrial stormwater permit.
However, if a facility has MNG49 and there are industrial activities with a listed SIC code or narrative activity that are not addressed in MNG49 (such as local trucking or a landfill), the facility must add an industrial stormwater permit for the location or part of the location that has these additional activities.
For more information or to find out if a facility qualifies for MNG49, see the MPCA’s Nonmetallic Mining and Associated Activities water permit web page at http://www.pca.state.mn.us/iryp90f. Be careful not to confuse it with the air quality permit that has a similar name.
On-site: On-site auxiliary operations, such as warehouses or vehicle maintenance shops, are considered Secondary SIC code activities. As discussed above in the section about SIC codes, a facility only needs a permit if the Primary SIC code or narrative activity is listed. If it is listed, get the permit and comply with the sector requirements for primary activities, auxiliary/secondary activities and any narrative activities, or certify for No Exposure.
Off-site: For off-site auxiliary operations, first determine whether industrial activities at the off-site facility have a listed Primary SIC code or narrative activity: · If so, an industrial stormwater permit or No Exposure exclusion is required for the off-site facility. · If the off-site facility does not have a listed Primary SIC code or narrative activity, the off-site facility takes on the SIC code or narrative activity of the facility it supports. If industrial activities at the main facility have a listed Primary SIC code or narrative activity, separate industrial stormwater permits or No Exposure exclusions are required for the off-site facility and the main facility. · If neither facility has a listed Primary SIC code or narrative activity, neither facility needs a permit or No exposure certification.
Pilot plants and research and development (R&D) facilities follow a similar decision process as other auxiliary operations:
Facilities primarily engaged in commercial physical and biological R&D on a contract or fee business are described by the Primary SIC code 8731. These facilities are not required to have an industrial stormwater permit or No Exposure certification.
Warehousing businesses that fit into one of the listed warehousing SIC codes (SIC 422x) must have a permit or certify for No Exposure. Warehouses located on-site at a facility that has a listed primary SIC code or narrative activity are included in that facility’s permit. Follow the sector requirements in the permit for Sector P – Land Transportation and Warehousing for the warehouses. Off-site warehouses of preassembly parts or finished products are not required to have a permit unless they are specifically a warehouse business described by a warehouse SIC code (SIC 422x).
Vehicle maintenance facilities follow a similar decision process as auxiliary operations unless they are associated with transportation facilities, which is discussed in more detail in the next section.
Independently-operated vehicle maintenance shops are usually described by Primary SIC codes 75xx or 7699. Neither of those SIC codes are listed, so facilities that fit those descriptions do not need an industrial stormwater permit or No Exposure certification.
For vehicle maintenance shops that provide support to a non-transportation facility:
Minnesota considers water from truck washing operations to be wastewater, not stormwater. Washwater cannot be discharged with stormwater.
More information is in MPCA stormwater fact sheet #wq-strm3-32, “Guidance on the Industrial Stormwater Permit for Transportation Sectors.”
The No Exposure certification will be difficult to qualify for and maintain at a transportation facility, even if all vehicle maintenance and equipment cleaning is done indoors. Vehicle fueling is a common source of pollutants. Vehicles waiting for maintenance at transportation facilities are unlikely to be in good condition, resulting in potential exposure of pollutants to stormwater. Outdoor storage of materials used in vehicle maintenance or equipment cleaning are common and can contribute pollutants to stormwater. Particulate matter or residuals from roof stacks or vents that are not otherwise regulated (such as by an air quality permit) and are evident in stormwater are also considered a violation of No Exposure.
Vehicle maintenance shops, equipment cleaning facilities and airport de-icing operations located at a facility in one of the transportation categories (Sectors P, Q, R and S) are regulated by the industrial stormwater permit. However, the permit requirements apply only to the areas where vehicle maintenance, equipment cleaning or airport de-icing are being done. If a transportation facility is not doing vehicle maintenance, equipment cleaning or airport deicing, the facility does not need an industrial stormwater permit or No Exposure certification.
Follow Sector P requirements of the permit for local or long distance trucking maintenance or fueling located at a facility with a listed Primary SIC code.
Exception: Facilities with Primary SIC codes 4221-4225 (warehousing) must have an industrial stormwater permit or certify for No Exposure regardless of whether vehicle maintenance shops, equipment cleaning facilities and airport de-icing operations are present.
EPA has determined that most off-site vehicle maintenance facilities are supporting establishments that take on the SIC code of the facility they support. This means facilities that provide local trucking maintenance, fueling or washing take on the SIC code of the facility they support. If the main facility is required to have a permit, so does the off-site facility. The off-site facility takes on the sector requirements of the main facility.
Exception: Industrial stormwater permits or No Exposure exclusions are always required for vehicle maintenance associated long distance trucking, stevedoring (4491) and water transportation (44xx). As noted above, qualifying for the No Exposure certification will be difficult.
The SIC code description for school bus transportation (SIC code 4151) excludes operations that are owned or run by a school district; these are instead covered under SIC code 8211, which is not a listed SIC code. This means school bus maintenance facilities that are owned or operated by a municipality or school district are not required to have an industrial stormwater permit or No Exposure certification.
However, private-contract school bus services (SIC code 4151) must have an industrial stormwater permit or certify for No Exposure. As noted above, qualifying for the No Exposure certification will be difficult.
Tank farms need an industrial stormwater permit if stormwater from the tank farm mixes with stormwater from a vehicle maintenance shop or equipment cleaning operation. Tank farms at petroleum bulk storage stations (SIC code 5171) that don’t have vehicle maintenance or equipment cleaning operations are exempted and do not need an industrial stormwater permit.
If the tank farm is located at a facility that has a listed Primary SIC code, the tank farm is considered a secondary activity and is included in the main facility’s permit.
More information is in MPCA stormwater fact sheet #wq-strm3-32, “Guidance on the Industrial Stormwater Permit for Transportation Sectors.”
Facilities that only warehouse or store farm products are described by Primary SIC code 4221 and must have an industrial stormwater permit or certify No Exposure.
Grain elevators described by Primary SIC code 5153 do not need an industrial stormwater permit or No Exposure certification. They include elevators buying or marketing grain or beans, country grain elevators buying or receiving grain or beans from farmers and terminal elevators and other merchants marketing grain or beans.
Wood mulch or animal bedding manufacturing are described by one of three listed SIC codes:
Facilities with any of these Primary SIC codes are regulated by the industrial stormwater permit.
The overarching SIC code 9711 (national security) does not apply to industrial activities at a military facility. Each industrial activity on a military base or state reserve facility such as National Guard is considered to be a stand-alone industrial activity. EPA requires a separate permit or No Exposure exclusion for each listed industrial activity. This is unique to federal military facilities.
Section 313A of the Clean Water Act states that federal facilities "shall be subject to, and comply with, all federal, state, interstate, and local requirements... respecting the control and abatement of water pollution in the same manner, and to the same extent as any nongovernmental entity including the payment of reasonable service charges."
State and local municipal facilities follow the same decision-making process as any industrial facility. Start by determining the Primary SIC code and then evaluate on-site secondary and off-site auxiliary activities.
Publicly-owned government facilities usually are described by Primary SIC code 9199 – General Government, because the greatest revenue source and number of employees are from government administration. SIC code 9199 is not a listed SIC code so an industrial stormwater permit or No Exposure certification is not required. Common industrial activities such as police cars, fire trucks and snow plows are covered by SIC codes 9221, 9224 and 9229; dump trucks and heavy equipment used for construction are covered by SIC codes 1611-1629. None of these activities have listed SIC codes or narrative activities so an industrial stormwater permit or No Exposure certification is not required. This also means that secondary activities at these facilities, such as a Sector N recycling center or a warehouse, do not trigger the need for a permit or No Exposure certification. Off-site vehicle maintenance facilities supporting these SIC codes do not need the permit or No Exposure certification.
A vehicle maintenance facility located on-site at a municipal waste water treatment plant or landfill, which are listed narrative activities and require an industrial stormwater permit, is covered by the main facility’s permit.
A separately located recycling center needs an industrial stormwater permit or No Exposure certification; it is not considered to be auxiliary.
Question 20 lists municipal solid waste activities that do not need an industrial stormwater permit or No Exposure certification.
Schools follow the same decision-making process as any industrial facility. Start by determining the primary SIC code and then evaluate on-site secondary and off-site auxiliary activities.
Public or private universities described by primary SIC code 8221 (Colleges, Universities and Professional Schools) that do not have on-site narrative activities are not required to have an industrial stormwater permit or No Exposure certification. On-site secondary activities with listed SIC codes do not trigger the need for a permit or No Exposure certification. Off-site auxiliary activities such as warehouses or vehicle maintenance shops are not required to have a permit or No Exposure certification.
Public or private university campuses with a narrative activity are required to have an industrial stormwater permit and follow the requirements for the narrative activity’s sector. All industrial activities at the main campus are covered by the permit, including warehouses, vehicle and equipment maintenance facilities, printing presses and recycling centers. Off-site industrial activities supporting the main campus take on the narrative activity and are required to have the permit or No Exposure certification. The main campus and the supporting facility each need their own permit or No Exposure certification. Both follow the requirements of the narrative activity’s sector. A separately located warehouse does not need the permit or No Exposure certification (see section on warehouses for more information).
An off-site, university-run facility described by a listed Primary SIC code must have an industrial stormwater permit or No Exposure certification. Common examples are off-site, university-run printing presses or recycling centers. They are described by listed Primary SIC codes 27xx and 5093, respectively, and therefore must get a permit or No Exposure certification. The main campus does not need an industrial stormwater permit or No Exposure certification.
An off-site, university-run facility described by a narrative activity must have an industrial stormwater permit or No Exposure certification. If auxiliary activities are conducted at the off-site facility, all of these activities are covered by the permit. The main campus is not required to apply for an industrial stormwater permit or No Exposure certification.
Most wastewater treatment plants are described by the Sector T narrative activity and therefore must have an industrial stormwater permit.
Vehicle or equipment maintenance associated with a wastewater treatment facility (for example, to haul sewage sludge or to move equipment from the maintenance facility to the treatment plant), whether on-site or off-site, takes on the classification of the main facility and is required to have an industrial stormwater permit if the facility does. If the maintenance facility serves multiple wastewater treatment authorities, it is required to have an industrial stormwater permit.
Wastewater treatment facilities that collect their stormwater runoff and treat the stormwater as part of the normal inflow processed through the treatment plant are not required to have an industrial stormwater permit or No Exposure certification. Stormwater mixed with wastewater becomes wastewater and is addressed by the NPDES wastewater permit for the facility.
Off-site areas where sludge (biosolid) is beneficially reused do not need an industrial stormwater permit or No Exposure certification. For the purposes of the industrial stormwater permit, beneficial reuse of sludge is the application of sludge as a nutrient builder or soil conditioner. It can include agricultural or domestic application.
Off-site pumping stations do not need an industrial stormwater permit or No Exposure certification.
An industrial stormwater permit or No Exposure certification is not required for solid waste facilities that are exempted from solid waste permitting, or, are granted a solid waste permit without applying for it by Minn. R. 7001.3050, subp.2 and subp.3. This includes the following:
The following facilities are required to have an industrial stormwater permit or certify for No Exposure: